Weekly Patent Review

Kodak filed an application US20080315272 on control of 4T pixel floating diffusion capacitance in such a way that it's low for small signals and large for large signals. The pixel schematics is shown below:


Transistor 201 opens only for large signals, increasing floating diffusion capacitance to accomodate the larger charge.

Omnivision's application US20080318358 talks about using indium doping for the photodiode pinning layer. Indium allows for a shallower implant layer with higher concentration than commonly used boron. An indium-boron combination is also applied for the patent.

Image Sensors on Electronic Imaging 2009 Symposium

2009 IS&T/SPIE Electronic Imaging Science and Technology Symposium will be held on January 18-22 in San Jose. The conference has a full track on image sensors and related areas. Below are just few of the most interesting papers to be presented on the Symposium:

Nanoplasmonic filters for image sensors
Author(s): Stephane Getin, Yohan Désières, Catherine Pellé, Olivier Lartigue, Ludovic Poupinet, Laurent Frey, Commissariat à l'Energie Atomique (France)

Potentially these filters can substitute today's organic ones. I wonder how far they have to go till the mass production.

An ultra fast 100 ps, 100µm 3D pixel imager
Author(s): Alex Kluge, Pierre Jarron, Jan Kaplon, Petra Riedler, Teemu S. Tiuraniemi, Fadmar Osmic, CERN (Switzerland); Giulio Dellacasa, Gianni Mazza, Angelo Rivetti, Sorin Martoiu, Angelo C. Ramusino, Massimiliano Fiorini, Istituto Nazionale di Fisica Nucleare (Italy); Elena Albarran Martin, CERN (Switzerland)

A global electronic shutter pixel using pinned diodes fabricated in standard CMOS image sensor technology
Author(s): Keita Yasutomi, Shizuoka Univ. (Japan); Toshihiro Tamura, Photron Ltd. (Japan); Masanori Furuta, Toshiba Corp. (Japan); Shinya Itoh, Shoji Kawahito, Shizuoka Univ. (Japan)

It's interesting to see Toshiba eying toward global shutter solution.

Low Gr-Gb sensitivity imbalance 3.2M CMOS-image sensor with 2.2-μm pixel
Author(s): Nagataka Tanaka, Junji Naruse, Hirofumi Yamashita, Ikuko Inoue, Makoto Monoi, Toshiba Corp. (Japan)

It's nice to see that Toshiba still improves 2.2um generation.

Experimental color video capturing equipment with three 33-megapixel CMOS image sensors
Author(s): Takayuki Yamashita, NHK Science & Technical Research Labs. (Japan); Steven Huang, Forza Silicon Corporation (United States); Ryohei Funatsu, NHK Science & Technical Research Labs. (Japan); Barmak Mansoorian, Forza Silicon Corporation (United States); Kohji Mitani, Yuji Nojiri, NHK Science & Technical Research Labs. (Japan)

This paper sheds some light on Forza's customers and projects.

Computational modeling of CMOS image sensor pixels: from module lens to photoelectron
Author(s): Jeff Mackey, Victor A. Lenchenkov, William Gazeley, Xiaofeng Fan, Ulrich C. Boettiger, Gennadiy A. Agranov, Aptina Imaging (United States)

A day and night MOS imager spectrally adjusted for a wide range of color temperatures
Author(s): Shinzo Koyama, Masahiro Kasano, Keisuke Tanaka, Kazuo Fujiwara, Toshinobu Matsuno, Yutaka Hirose, Yasuhiro Shimada, Panasonic Corporation (Japan)

High-speed sequential image acquisition using a CMOS image sensor with a multi-lens optical system and its application for three-dimensional measurement
Author(s): Daisuke Miyazaki, Hiroki Shimizu, Osaka City Univ. (Japan); Yoshizumi Nakao, Takashi Toyoda, Yasuo Masaki, Funai Electric Co., Ltd. (Japan)

3D imagers becoming a field of quite intensive work.

Very-large-area CCD image sensors: concept and cost-effective research
Author(s): Erik W. Bogaart, Inge M. Peters, Agnes C. Kleimann, Erik-Jan P. Manoury, Wilco Klaassens, Walter de Laat, DALSA Corp. (Netherlands); Cees Draijer, Raymond Frost, DALSA Corp. (Canada); Jan T. Bosiers, DALSA Corp. (Netherlands)

Decoupling light collection efficiency and color crosstalk from the Quantum Efficiency Spectrum for the CMOS image sensor pixel development
Author(s): Yang Wu, Philip J. Cizdziel, Howard E. Rhodes, OmniVision Technologies, Inc. (United States)

This very rare appearence of Omnivision pixel team should not be missed.

Microlens performance limits in sub-2um pixel CMOS image sensors
Author(s): Yijie Huo, Christian C. Fesenmaier, Peter B. Catrysse, Stanford Univ. (United States)

Sensor information capacity and spectral sensitivities
Author(s): Frédéric Cao, Frédéric Guichard, Hervé Hornung, DxO Labs. (France)

2PFC CMOS image sensors: better image quality at low cost
Author(s): Douglas J. Tweet, Jong-Jan Lee, Jon M. Speigle, Sharp Labs. of America, Inc. (United States); Daniel Tamburrino, Sharp Labs. of America, Inc. (United States) and Ecole Polytechnique Federale de Lausanne (Switzerland)

I don't know what is 2PFC, but if it really delivers better image at lower cost, we'll see Sharp among the image sensor leaders again.

Effects of imaging lens f-number on sub-2 µm CMOS image sensor pixel performance
Author(s): Christian C. Fesenmaier, Peter B. Catrysse, Stanford Univ. (United States)

Effects of imaging lens f-number on sub-2 µm CMOS image sensor pixel performance
Author(s): Christian C. Fesenmaier, Peter B. Catrysse, Stanford Univ. (United States)

Measuring texture sharpness of a digital camera
Author(s): Frédéric Cao, Frédéric Guichard, Hervé Hornung, DxO Labs. (France)
Add to My Schedule

Interaction of image noise, spatial resolution, and texture preservation in digital image processing
Author(s): Uwe Artmann, Dietmar Wueller, Image Engineering Dietmar Wüller (Germany)

Mobile imaging: the big challenge of the small pixel
Author(s): Feng Xiao, Fairchild Imaging (United States); Joyce E. Farrell, Peter B. Catrysse, Brian Wandell, Stanford Univ. (United States)

Reduction of motion blur for handheld captured images by joint stabilization and spatio-temporal denoising
Author(s): Alfio Castorina, Giuseppe Spampinato, Arcangelo Bruna, Alessandro Capra, STMicroelectronics (Italy)

Extended depth-of-field using sharpness transport across color channels
Author(s): Frédéric Guichard, Imène Tarchouna, Marine Pyanet, Régis Tessières, Frédéric Cao, DxO Labs. (France)

People first: separating people from background in digital photographs
Author(s): Mihai Ciuc, Tessera Romania SRL (Romania) and Univ. Politehnica Bucuresti (Romania); Adrian Capata, Tessera Romania SRL (Romania); Alexandru F. Drimbarean, Tessera Ireland Ltd. (Ireland); Eran Steinberg, Tessera (FotoNation) Inc. (United States); Adrian Zamfir, Tessera Romania SRL (Romania)

Patent: Aptina Gets Rid Of RST Wiring

Micron filed a patent application US20080291310 on 4T pixel with no global RST transistor wiring. The principle is quite self-explanatory from the picture below:

Caeleste on 3D Integration Ideas

Bart Dierickx from Caeleste presented his 3D sensor ideas on IEEE Nuclear Scinece Symposium in Dresden, Germany, Sep. 2008. The presentation talks about the new design approaches in 3D world. One might give up pinned photodiode and 4T CDS scheme and needs to look for other ways to suppress kTC noise.

Bart presents an idea how this can be accomplished without resorting to active reset schemes. I'm unable to understand how come that the proposed reset reduces kTC noise, but the eldo transient noise simulation in the inset seems to confirm this:

Gamma Scientific Digital Light Sources

While we are at testing, Gamma Scientific offers calibrated digital light sources for image sensor testing in its Eigenlite RS-5 series. The sources can be used for photometric and radiometric calibrations and sensor's linearity tests.

HyVISION System - Image Sensor Testing Solutions

It came to my attention that Korea's HVS - HyVision System offers a full range of solutions for testing image sensors and camera modules, starting from simple PC add-on boards all the way to the automatic module production testers.

Omnivision's Orders Down

Digitimes: TSMC has received few orders from OmniVision in December, which is a sign of the client's pessimistic outlook for the handset market in the first quarter of 2009, according to Digitimes sources.

Micron Reports Quarterly and Yearly Results

Yahoo: Micron reports relatively stable image sensor quarterly sales compared to the preceding quarter. The company’s gross margin on sales of Imaging products also remained stable compared to the previous quarter, reflecting a slight decrease in costs per part.

Seeking Alpha Micron's Earnings Call transcript has just one mention about imaging business:

Hans Mosesmann – Raymond James analyst:

On the sensor business it was flat and that’s unusually strong too in this environment, are you gaining share or is it that you’re not exposed to some of the markets where perhaps they’re seeing a lot more weakness then you saw.

Steven Appleton, CEO:

I think we did gain some share in the quarter but if you looked at some of the other forecasts and the competition, I think that’s indicative of what we’ll probably experience too. In other words I don’t think we’re going to escape the general economic decline and we would expect, and by the way its also the season of course is weaker, so we would expect for the what we call our Q2 or the calendar Q1 to be inline with what others are forecasting and it’ll be down for the quarter.

Intertech-Pira Image Sensors Europe 2009

Intertech-Pira Image Sensors Europe 2009 conference published a provisional program. The conference is to be held on March 24-26, 2009 in London, UK. The program has quite a few interesting presentations:

Market analysis for image sensors in portable communication devices
Stuart Robinson, Director - Handset Component Technologies, STRATEGY ANALYTICS, UK

The latest technical developments from Advasense Technologies Ltd.
Arie Gravriely, Director Marketing and Business Development, ADVASENSE TECHNOLOGIES, Israel

New design for CMOS sensor: A wide dynamic range imager with user definable response
Steve Collins, Professor, OXFORD UNIVERSITY, UK

Technical developments in image sensors for portable electronic devices
Guy Michrowsky, VP Marketing and Sales, DBLUR TECHNOLOGIES, Israel

Market developments in medical imaging technology
Eric Dahlinger, MICRO-IMAGING SOLUTIONS LLC, US

Custom APS devices and systems for scientific and medical imaging - and routes to getting custom sensors
Nigel Allinson, Leader, UK BASIC TECHNOLOGY CONSORTIUM ON ACTIVE PIXEL SENSORS, UK

Recent developments in high dynamic range image sensors
Jung Hunjoon, ClAIRPIXEL, Japan

Imaging in non-consumer markets – trends and opportunities
Gareth Powell, CMOS Marketing Manager, E2V

Advanced packaging technologies, and developments in backside illumination
Jerome Baron, Technology Marketing Analyst, YOLE DEVELOPPEMENT, France

Opening a new image sensors plant –streamlining manufacturing and the supply chain
Nobukazu Teranishi, PANASONIC, Japan (invited)

Impact of TV frame rates and future display technology on image sensor requirements
Richard Salmon, Senior Research Engineer, BBC RESEARCH AND INNOVATION, UK

Developments in image sensors for the automotive sector
Tom Hausken, Director, STRATEGIES UNLIMITED, US (invited)

Update: And I just forgot to mention, there are two workshops:

Workshop 1: Colour processing for digital cameras
Prof Dr Albert Theuwissen, Digital Imaging Expert and Founder, HARVEST IMAGING, Netherlands

Workshop 2: Optimisation of image sensor testing processes
Nicolas Touchard, VP Marketing, Image Quality Assessment, DXO LABS

Mediatek To Enter DSC Processor Market

Digitimes: Mediatek is expected to enter DSC processors market with an entry-level 7MP DSC chip solution in Q2 2009. Digitimes sources indicated that Mediatek initially will target DSC market in China by tapping white-box and local brands.

Panasonic Reorgs, Buys Sanyo

EETimes: After many months of negotiations Panasonic acquired Sanyo for $9B. At some point Sanyo was the biggest CCD manufacturer for camera phones, but it was unable to switch over to CMOS sensors and lost its market share. Still, Sanyo produces a number of CCDs till now and has CCD-dedicated fab. The acquisition should strengthen Panasonic image sensor group.

In a separate move Panasonic will absorb its wholly owned subsidiary Panasonic Semiconductor Device Solutions Co. Ltd. (PSCDS). PSCDS used to be responsible for the camera module business. The move is expected to take effect on April 1, 2009.

Toshiba Discusses Camera Phone Trade-Offs

Embedded Design India published Toshiba's article on choices and criteria in design of camera-phones (pdf is here).

More About Rohm, AIST Presenting CIGS Sensor on IEDM

Tech-On published yet another report on IEDM presentation of Cu-In-Ga-Se image sensor by Rohm and AIST. The sensor has a layer structure composed of n-type ZnO, i-type ZnO, CdS, CIGS and Mo, which are arranged in this order from the top surface. The sensor is placed on a Si LSI via the molybdenum (Mo) layer serving as an electrode. The ZnO layer was formed using RF sputtering. The sensor works in avalanche multiplication mode.

Pixim Raises $13M

Venture Beat: Despite the investment freeze talk, Pixim raises $13M from Mayfield Fund, Ridgewood Capital and Tallwood Venture Capital. The company will use the money to accelerate its expansion in overseas markets, fuel new product development, and expand its marketing and sales programs. China is about 15% of its business, but Korea and Taiwan are also big markets, as are the U.S. and Europe.

Customers include the biggest makers of security cameras: GE Security, Honeywell, JVC, Pelco, Dallmeier, and Siemens. Pixim has now raised $106.7M, including the latest round.

Kodak HD CCD is on EDN 100 Hot Products List

There is only one image sensor in EDN's list of "The Hot 100 Electronic Products of 2008" and it's Kodak KAI-02150 CCD. What makes this 2/3" CCD different is its ability to provide 1080p HD video at 60fps speed. Congratulations, Kodak!

DALSA Presents 48MP CCD

Yahoo: Dalsa presents its new 48MP 6um-pixel CCD for professional photography in a presentation at IEDM. Eric-Jan Manoury, a scientist at DALSA's Eindhoven R&D lab, gave the presentation titled "A 36x48mm2 48M-pixel CCD imager for professional DSC applications," highlighting the advances it delivers in increased QE, lower noise, and higher DR compared to previous generation or competitor devices.

This is claimed to be the first large image format imager with high pixel rate of 100 MHz, 74 dB of DR and 55000e of full well capacity. The IEDM article is published on Dalsa site.

IEDM Image Sensors Content

Solid State Technology published Chipworks analyst Dick James' report from IEDM'08. Here is what Dick says about image sensors:

"Chipworks has been focusing on image sensors for a while now, so Rohm's announcement of a CIGS on CMOS sensor (paper 11.2) caught my attention. CIGS (copper indium gallium selenide) is one of the hot materials in the PV field, so the idea of using it for an image sensor is not that far off the wall -- the big problem has been high dark current.

Rohm gets around this by using a double layer of zinc oxide as the top blanket electrode. One layer is semi-insulating ZnO, and the top sub-layer is Al-doped to give conductivity; this has the dual advantage of isolating the pixels and reducing dark current. The CIGS is co-evaporated on to a molybdenum base layer/back contact (which contacts the top metal layer of the CMOS scanning chip below), with a CdS buffer layer under the ZnO bi-layer.

The pixels are 10μm × 10μm in a 352 × 288 array, so this is clearly a proof of concept. The sensitivity can be extended to sub-lux illumination levels by biasing the photodiode to induce avalanche multiplication. Since the photodiodes are on top of the die, they have an aperture ratio close to 100%, and this coupled with the CIGS spectral response extending into the near-infra-red makes the sensor suitable for automotive and security applications.

In the same session Samsung compared 1.4μm frontside- and backside-illuminated (BSI) sensors (paper 11.4).
....
Samsung claims that the technology will extend pixel size down to ~1μm."

Toshiba Gives Rest to its Wafer Lines

Earth Times: Due to the current economic slowdown, Toshiba plans to stop production for short periods at some of its fabs. One of the facilities affected is Oita operations, responsible for image sensors and SoC LSI production. The 300mm wafer lines will stop on January 5 and 6 for maintenance and other lines will stop for 22 days from December 24 to January 14.

My understanding is that Toshiba image sensors are manufactured on 200mm lines (am I right?), meaning they are to shut down for 22 days.

Omnivision Received EDN's Best Of 2008 Award

Yahoo: OmniBSI has been selected by Electronic Design Magazine as the 2008 'Best Image Sensor Technology'. The publication's annual 'Best Electronic Design' awards are based on editor's choice of the most significant designs and innovations introduced throughout the year. OmniVision's BSI technology was selected for its revolutionary approach to digital imaging.

Weekly Patent Review

Magnachip's application US20080296630 talks about applying negative bias voltage to transfer gate transistor during the integration. It looks like today everybody uses negative bias to reduce dark current. One possible problem here is increase in blooming and everybody solves it in its own way. Magnachip proposes a special burried channel for blooming current. This complicates the doping scheme of the transfer gate area, so I doubt that this idea finds a big use.

Nokia camera team filed application US20080297816 on improved black level correction. They try to compensate black level gradients across the sensor array by measuring black level in many points on the periphery of the array and interpolating the results for all the pixels, doing it separately for each color. There is nothing unusual in the idea itself, other than it points out that the black level spatial variations is probably the real problem in the sensors that Nokia uses.

Advasense Presentation On-Line

Advasense put its Intertech-Pira Image Sensors 2008 Conference presentation on-line (the first one in the list here).

The main statement in the presentation is that modern small pixel sensors are not good in capturing image: in good light there is no enough full well capacity, while in low light there is no enough photons. So, the company proposes its large full well photodiode as a solution for daylight, while an on-sensor embedded image stabilization is supposed to increase signal at low light.

Thanks to A.G. for letting me know about the presentation.

Chipworks Reveals Omnivision Split Pixel Internals

Chipworks did a first round of analysis on Omnivision split pixel sensor back in April and kindly agreed to shed some light on the subject even though they haven't gone forward with a full analysis. Chipworks has posted a flyer based on the brief analysis, a custom landing page can be found here. (This page is temporary, so keep the pdf file, if you need it.)

The design is quite interesting. Each pixel has two photodiodes per each 6um pixel, as depicted below:



Each split pixel has dual microlens above, one per each photodiode (I think Visera spent many sleepless nights to optimize these oval lens shapes):



It looks to me that Omnivision used dual exposure technique to achieve its goal of 110db DR with this sensor. Two interleaved rolling shutters can run across the array, where reset curtain is followed by two read curtains - short and long one. Then the two readouts are combined into a single HDR image. Obviously, there should a large memory to hold the intermediate frame results. The die photograph in Chipworks document supports this guess, showing a huge memory-dominated digital portion.

So, to me this looks like a dual exposure sensor with on-chip HDR reconstruction. Its main competition are Pixim digital pixel and Toshiba-like dual exposure pixels with charge skimming.

In principle Pixim can get better dynamic range, but I believe Omnivision 4T pixel is better in low light, especially if two photodiodes operate in normal mode, with same exposure on the two photodiodes.

Comparing it with Toshiba solution, I'm less sure about Omnivision advantages. Toshiba sensor might have some linearity artifacts when connecting short and long exposure ranges. Omnivision probably does not have this. However, Toshiba has an advantage in low-light sensitivity in HDR mode because Omnivision sensor effectively loses half of the light for the short exposured photodiode.

One question that bothers me though, is that the two photodiodes are spacially shifted relative each other. So, there might be some color artifacts when interpolating the edges on HDR picture. It's probably not something fundamental, but might take some effort to correct.

Many thanks to R.F. from Chipworks for providing this presentation!

Analyst is Skeptical about Omnivision

Yahoo: Robert W. Baird & Co. analyst Tristan Gerra told investors in Dec. 3 note that competition from "ultra-low-cost" rivals based in Asia is driving the company's revenue decline. Gerra added that OmniVision is likely to lose more market share next year as more mobile phone makers switch to higher-resolution sensors -- a market in which the company is not as well-positioned as competitors.

So, it looks like Gerra does not count on Omnivision's BSI and EDoF success, which, in theory, could propel the company to the market leader position in high-res products. I wonder why he is that skeptical?

Reverse Engineering Companies Merge

EETimes: United Business Media Ltd., the publisher of EE Times, has acquired for at least $8M Sanguine Microelectronics, a semiconductor reverse engineering company based in Shanghai. UBM will merge Sanguine into its existing Semiconductor Insights (SI) group in Ottawa that provides chip and patent analysis services. The deal also includes possible payments of up to $9.5M to the Shanghai company over three years if the company meets unspecified business targets.

The deal nearly double's SI's headcount and expands its lab capabilities. Sanguine employs about 130 people with a lab in Shanghai and an office in France and has annual revenues of about $4 million. SI has about 160 employees with labs in Ottawa and Warsaw and sales offices in Japan, Korea, Singapore, Taiwan, China, Europe and Israel.

Both companies published a lot of reverse engineering reports on image sensors, albeit their recent focus seems to shift elsewhere.

Omnnivision Splits Pixel

It was brought to my attention that Omnivision's PR from a week ago mentions so-called "split pixel":

"The OmniVision OV10620 HDR sensor incorporates a unique split pixel design that operates using different exposure times to allow one part of the pixel to capture dark tones within an image, and the other part to capture bright tones. The two images are then merged using proprietary signal processing technology ensuring the visibility of entire scenes in high-contrast environments. The OV10620 is capable of performing at a dynamic range of up to 110dB in either color or black and white."

Anybody can shed some light on this pixel work? Any published patents on it?

Thanks to OA for bringing this to my attention.

Sony Cuts Image Sensor Investment, Plans Outsourcing

EETimes: Sony plans to slash about 8,000 jobs in its electronics business, or about 5 percent of its work force in the sector. The cutbacks involve its CMOS image sensor and other product areas. As part of the plan, Sony intends to cut IC investment expenditures this fiscal year by outsourcing a portion of its planned increase in the manufacturing of CMOS image sensors for use in mobile phones.

Update: Official Sony PR is here.

Aptina Ships One Billionth Image Sensor

Yahoo: Aptina announced that it shipped one billion image sensors since it began manufacturing image sensors in 2002. Of the one billion sensors shipped, approximately 55 percent were megapixel or greater. Aptina maintains a product portfolio of over 70 CMOS image sensors.

Nemotek Features on I-Micronews Site

Yole's site I-Micronews published an interview with Youssef Benmokhtar, Marketing & Business Development Director on Nemotek, the first licensee of the full portfolio (SHELLCASE and OptiML) from Tessera.

The company was established in September 2007 as a subsidiary of MEDZ (a Moroccan company with more than 1.2B$ of assets) as a Government initiative to position Morocco as a key player within the microelectronics industry and new sciences arena. Nemotek is claimed to be the only company in the world to date to offer a one-stop-shop approach for wafer-level cameras.

Advasense on Pixel Size Shrink

One more interesting presentation from Itertech-Pira Image Sensors 2008 Conference is Advasense one. Here is how Advasense sees the pixel size shrink progress with respect to full well:



Advasense's solution of diminishing full well problem is using its own Feedback Controlled Pixel - FCP. Here is the explanation why FCP has higher full well:



And here is one more comparison of deep photodiode full well with shallow photodiode:

Weekly Patent Review

I always enjoy reading Siliconfile patents. It looks to me that the company has quite a few unusual, sometimes bright, ideas. The newly ublished application US20080290440 proposes to reduce the light reflection from silicon by using "concavo-convex surface" shaped surface. The picture below shows how exactly this reduces the reflection:



I'm not sure if this idea works for small pixels, where pixel size is of close to wavelength. Also, I believe the process of creating such a surface is not simple. But I like fresh, out of the box thinking of Siliconfile engineers.

Application US20080291309 by University of Pennsylvania in Philadelphia talks about pixel with amplifier transistor, instead of source follower. The application is written in a scientific paper style, with good comparison of different techniques and their strong and weak points. While I don't like their idea and especially their proposed implementation, it's a good educational read.

Chipworks is About to Publish Sony 1.4um Sensor Reverse Engineering Report

Chipworks got a hold of a Sony 1.4um 8MP IMX046 sensor in a commercially available product (probably from LG or Sony-Ericsson phone). The formal report announcement is prepared for next week. The die picture below reveals very compact sensor design. I hold my breath to see the full report available.



Thanks to R.F. for the information.

Samsung Launches HD Sensor for PCs

Yahoo: Samsung announced that it has expanded its portfolio of CMOS image sensors to include a new high-definition 1/4-inch, 1.2MP SoC imager, the S5K4AW, for notebook and desktop computers. Instead of more usual 1.3MP, 1.2MP is better suited for HD video applications. By binning in 2x2 pixel groups, the S5K4AW’s 1.2Mp resolution (1280x960 pixel format) also can display standard VGA format without annoying problem of losing the top or the bottom of a scene while video conferencing or video file sharing on social media networks such as YouTube.

The binning technique used by Samsung’s new S5K4AW sensor for VGA resolution also significantly improves the imager’s sensitivity to low light. Samsung claims that the industry’s typical method of binning results in an improved sensitivity of approximately 1.2x - I'm not sure how they got this number. Samsung’s 2x2 binning shows a sensitivity improvement of nearly 3x. This is critical when the only illumination on the scene might be from the computer screen itself.

The new S5K4AW imager is a 1/4-inch sensor that uses a 2.8um pixels. It supports 720p HD video at 30fps and VGA video at up to 60fps.

Samsung is currently sampling S5K4AW sensor to select customers. Mass production is expected in the first half of 2009.

Omnivision Quarterly Earnings Call

Seeking Alpha publishes a transcript of Omnivision Q2 FY2009 Earnings Call. As many have expected, the guidance for the next quarter is down and the company forecasts an operating loss. Its strong cash position of $283M should help it survive and continue to invest in new technologies during the downturn, at least Shaw Hong, the CEO, believes so. He also tells that the company has already taken steps to reduce its operating expenses.

Gross margin for the Q2 was 25% compared to 25.2% the previous quarter. Excluding stock-based compensation expense gross margin was 25.4% compared to 25.7% reported in the Q1.

Omnivision continues its work to migrate to 300-millimeter wafer production, both with TSMC and VisEra.

Ray Cisneros, VP of Sales, says:

During our fiscal second quarter, we sold about 99 million units into the marketplace.
....
Our 2-megapixel sensor shipments into smart phones have been particularly strong over the past two quarters. And now, this quarter, we have ramped up our 3-megapixel sensor shipments.
....
just over 60% of our revenues came from the mobile phones and just under 40% from emerging products. As for the unit mix in the quarter, the VGA and below was 65%, 1.3-megapixel was just over 15%, and 2-megapixel and above was just below 20%.
....
sensors on notebooks represented our strongest growth area during the quarter and represented approximately 30% of the company’s revenue.

One of suspicious omissions in the conference call was absence of any word on BSI sensor volume production start, general sampling or design wins. No analyst asks about it in Q&A session either. This brings some food for thought.

Correction: As written in comments, the earnings call does have a statement that two BSI products will be qualified for mass production in the first half of 2009.

Tessera on Mobile Imaging - Part 4

Mobile Handset Design Line publishes part 4 of Tessera mobile imaging challenges and solutions article. This part talks about image processing extensions to make cheaper and better camera modules, such as cheaper lens aberration correction, red eye removal and face detection features.

Altasens Presents Tapered Reset in 4T Pixel

Altasens presents its new idea on tapered reset usage in 4T pixel on Intertech-Pira Image Sensors 2008 Conference. The pixel has 2 modes of operation. At large signal it works like any other 4T pixel. In low light mode the pixel transistor works in common source mode where the photodiode charge is transferred to its Miller capacitance. This way pixel has a higher gain, so that the column circuitry noise is less important. The slide below shows the idea:

Sony 1.4um Picture on Intertch-Pira Conference

Sony presented a picture from its new 8MP 1.4um pixel sensor on Intertech-Pira Image Sensors 2008 Conference. The picture is given below, as appeared in Sony .pdf file. Essentially, this is a copy of the picture from the official Sony PR, but with higher resolution and illumination conditions reported. The picture is quite good for a first generation sensor (click on it to expand):

DALSA "High Quanta" Sensor Family Grows

Yahoo: Two new DALSA High Quanta sensors with resolutions of 1044 x 1044 (IA-DJ-01044-00-R) and 524 x 524 (IA-DJ-00524-00-R) feature the same 24 um size pixel. The new sensors are said to employ the latest designs in output amplifiers providing low noise at high data rates.

The sensors are available now and will be showcased this week at the Radiological Society of North America (RSNA) Show. For applications demanding UV sensitivity and > 90% QE, back side thinned (BST) devices will be available on a custom basis. The standard front side illuminated product's QE is said to be peaking at more than 70%.

Sony Describes 1.75um Sensor Generation

Vol. 54 of Sony Semiconductor's quarterly magazine CX-News presented 3MP, 5MP and 8MP CMOS sensors based on 1.75um pixels.

The whole family is targeted to camera phone applications. 3MP IMX029 and IMX058 differ by the interface type: IMX029 has serial interface while IMX058 has parallel one. 5MP IMX034 and 8MP IMX043 have conflicting data on their interface: the header claims they use parallel one, while later in the text both are mentioned as having serial sub-LVDS interfaces. 8MP IMX043 is able to operate at 15fps speed at full resolution.

The sensors use 0.14um 1P4M Cu process, which allowed for an increase in chief ray angle, as compared with the 2.5um ancestor pixel.

Weekly Patent Review

Magnachip applications US20080283885 and US20080283886 talk about saving a reset transistor in 4T pixel by substituting it by a diode built vertically above the substrate. 20080283886 pixel also uses JFET as a source follower transistor to reduce the noise, while 20080283885 pixel has a set diode, in addition to the reset one. The reset and set diodes are formed between the diffusion and poly, amorphous silicon, local epi-layer or metal (Schottky version). Probably, JFET was thrown in 20080283886 to improve its chances to be granted, as when each idea separately would be rejected (there is a good chance they would), it still might pass as a combination.

The set diode in 20080283885 application improves the reset operation of the reset diode by biasing both at slightly different voltage, so that a small forward current flows through the diodes, keeping floating diffusion at mid potential.

Sony application US20080284250 talks about 3-level power supply for powering transfer get of 4T pixel. 3 levels are used to reduce image lag and noise, but it creates a number of start-up problems in mobile device, where the highest voltage might be not available initially. Sony proposes a solution for this specific problem.

Sharp application US20080284891 describes about yet another circuit eliminating "black sun" effect. For those who is still suffering from it, it's worth reading.

Image Sensors on ISSCC 2009

ISSCC 2009 program just has been published (even though the page is still empty, clicking on "Press" drop down menu and choosing "Advanced Program" works). This year one of the pre-conference forums is devoted to Medical Image Sensors, quite interesting stuff.

There are many interesting ideas to be presented on the Imagers session. The most interesting to me is Toshiba 8MP sensor.

A 1/2.5-inch 8Mpixel CMOS Image Sensor with a Staggered Shared-Pixel Architecture and an FD-Boost Operation

N. Tanaka, J. Naruse, A. Mori, R. Okamoto, H. Yamashita, M. Monoi
Toshiba Semiconductor, Yokohama, Japan

A 1/2.5-inch 8Mpixel CMOS image sensor employs a staggered shared-pixel architecture to suppress Gr/Gb sensitivity imbalance. It also employs an FD-boost operation using the Cgs and Cgd of amplifier transistors to yield large FD capability and low dark random noise. It achieves a Gr/Gb sensitivity ratio of 99.7%, random noise of 2.6erms and a pixel capacity of 7.7ke-.

Now, when Toshiba says it, FD boost idea seems quite natural one to use. I have not heard anybody used it though.

Canon presents an interesting sensor, probably for camcorder applications:

A 1/3.2-inch 3.3Mpixel CMOS Image Sensor with a Column-Signal-Addition Method Using a PMOS Column Amplifier

H. Takahashi, T. Itano, T. Watanabe, K. Iwata, H. Akabori, S. Takimoto, R. Mishima, I. Ueno, K. Sakurai, T. Ichikawa, G. Momma, S. Inoue
Canon, Ayase, Japan

A 1/3.2-inch 3.3Mpixel CMOS image sensor is fabricated in a 0.15μm 1P3M CMOS process. A deep-photodiode-isolation pixel and PMOS column amplifier achieves 96μV/e- conversion gain, 7.2e-/s dark current at 60°C, and 2.5erms random noise. The sensor has a column-level signal-addition mode that realizes 15500e-/lx·s sensitivity (green pixel) and interlace scan.

Sanyo surprised me with its CMOS sensor for niche applications. I thought Sanyo has stopped developments of new image sensors, but it looks I was wrong:

A Charge-Multiplication CMOS Image Sensor Suitable for Low-Light-Level Imaging

R. Shimizu, M. Arimoto, H. Nakashima, K. Misawa, K. Suzuki, T. Ohno, Y. Nose, K. Watanabe, T. Ohyama, K. Tani
Sanyo Electric, Anpachi, Japan

A CIF-format charge-multiplication 0.35μm 2P4M CMOS image sensor with 10μm pixel pitch is presented. It can execute charge multiplication using impact ionization of photo-generated signals within each pixel. For a significant increase in SNR at low light levels, up to 60× charge multiplication is achieved at a readout speed of 100μs/frame.

Once we are at video applications, Aptina presents its high DR VGA sensor with very impressive spec:

A Dual-Conversion-Gain Video Sensor with Dewarping and Overlay on a Single Chip

A. R. Huggett, C. Silsby, S. Cami, J. Beck
Aptina Imaging

A 47mm2 video sensor SoC comprises a 60fps 640×480 array of dual-conversion-gain 5.6μm pixels with >80dB DR, noise floor of <1erms and switchable sensitivities of 2.5V/lx·s or 11.9V/lx·s
and corresponding PRNUs of 0.57% or 0.68%, a video processor for correcting optical warp of up to 96 lines together with perspective adjustment, and a video overlay circuit.

Another interesting design is fashionable 3D-stacked sensor:

A 4-Side Tileable Back-Illuminated 3D-Integrated Mpixel CMOS Image Sensor

V. Suntharalingam, R. Berger, S. Clark, J. Knecht, A. Messier, K. Newcomb, D. Rathman, R. Slattery, A. Soares, C. Stevenson, K. Warner, D. Young, L. Ang, B. Mansoorian, D. Shaver
MIT Lincoln Laboratory, Lexington, MA
Irvine Sensors, Costa Mesa, CA
Forza Silicon, Pasadena, CA

A 3D-integrated back-illuminated 1Mpixel CMOS image sensor tile includes a stack of 2×32-channel vertically integrated ADC chips, and requires 13.4μm of silicon perimeter to the pixel array. The tile and system connector design supports 4-side abuttability and burst data rates of 1Mpixel in 1ms.

Another interesting paper talks about column-parallel cyclic ADC:

A 0.1e- Vertical FPN 4.7e- Read Noise 71dB DR CMOS Image Sensor with 13b Column-Parallel Single-Ended Cyclic ADCs

J. Park, S. Aoyama, T. Watanabe, T. Akahori, T. Kosugi, K. Isobe, Y. Kaneko, Z. Liu, K. Muramatsu, T. Matsuyama, S. Kawahito
Brookman Lab, Hamamatsu, Japan; Shizuoka University, Hamamatsu, Japan

A CIS with 13b column-parallel cyclic ADCs is presented. A single-ended architecture with low read noise increases DR up to 71dB. A vertical FPN of 0.1erms is attained using digital CDS, which performs A/D conversion twice in a horizontal scan period of 6.83μs. The imager has 7.07V/lx·s sensitivity, 5.6μm ADC pitch, 61μV/e- conversion gain, 4.7erms read noise and <0.5 LSB DNL

I was expecting more papers on consumer low-cost BSI sensors and small pixels, but this year ISSCC seems to omit these themes - quite strange, considering the huge efforts that industry is spending on this stuff.

Fairchild Imaging Toys with 4T Pixels

Fairchild Imaging presented a 4T pixel paper on SPIE Astronomical Telescopes and Instrumentation Conference, 23-28 June 2008, Marseille, France. It shows quite a conventional 6.5um pixel made in 0.18um process. What really sets it apart is a very low full well - only 1.5Ke at most.

Update: As mentioned in comments, probably the full well is limited by column amplifier in high-gain mode. The pixel's native full well is probably higher, albeit the paper does not give an explicit number.
Update #2: Two sentences removed, as said in comments.

Cypress Tells about its Sensor for Holographic Applications

Advanced Imaging Magazine publishes Cypress article on sensors for holographic storage. Basically, all the sensor requirements are speed, speed and more speed, even at expense of SNR.

Omnivision Announces 1/10-inch Medical Sensor

Yahoo: Sony is rumored to sell low resolution CCDs for medical applications for hundreds of dollars each. Many other companies dream to penetrate to this market too.

Omnivision announces its second generation medical sensor. The OV6930 square sensor has a resolution of 400 x 400. The new sensor is based on 3um 4T pixels, has optical format of 1/10 inch and a packaged footprint of 1.8 mm x 1.8 mm. The sensor's size and high low-light performance enable its use in a broad scope of medical endoscopy applications including colonoscopy, gastroscopy, OB/GYN, urology and bronchoscopy.

OV6930 uses a new, patent pending serial I/O, which allows for two-wire cabling up to 14 feet and contributes to its very low power consumption of 80mW with and 10mW without IO usage. It's capable of operating at 30 fps in full 400 x 400 resolution, and 60 fps at 400 x 200 resolution. The pixel sensitivity is said to be 3300 mV/Lux-second.

Aptina Presents Third Generation of its 1.75um Pixel

Yahoo: Aptina announced MT9P013 5MP 1/3.2-inch image sensor based on improved 1.75um pixels. The new sensor leverages the same technology Aptina is integrating into its 1.4um image sensors. Specifically, MT9P013 sensor implements the light-gathering advancements from Aptina’s 1.4um pixel sensors. The new sensor’s low-light sensitivity improvement is 2X over the MT9P012 for binning modes.

The sensor supports 720p HD video at 60fps and full 5MP resolution at 15fps. The sensor includes 2-lane MIPI, CCP2 and Parallel interfaces.

MT9P013 samples are presently available with mass production scheduled for the end of January 2009.

Magnachip and Pixelplus Close Patent Dispute

Yahoo: One clear beneficiary of Magnachip exit from image sensor business is Pixelplus. MagnaChip has completely withdrawn its appeal on the disputed process patents in Seoul High Court. Given this, the previous lower court decision that Pixelplus did not infringe any of the disputed process patents asserted by MagnaChip has become final and conclusive, and MagnaChip's patent infringement claims on the process patents will no longer be contested or remain at issue.

Honestly, I've never understood the business justification of Magnachip's lawsuit. Pixelplus is a very minor player on the image sensor market. Even if convicted, it would pay an insignificant sum for the Magnachip's bottom line. To me this dispute seemed like settling some personal scores between people in the companies. After all, both Magnachip and Pixelplus people worked together at Hyundai Semiconductor and LG Semiconductor. May be some of them think that their ideas were stolen and look for punishment.

DxO Reveals Its Image Sensor Metrics

Yahoo: At Intertech-Pira Image Sensor 2008 conference in San Diego, DxO Labs today unveils www.dxomark.com, a new website claiming to present objective metrics of sensor performance for a variety of cameras measured directly on the RAW image. “There are many valuable resources reviewing the image quality of digital cameras, but none of them consider the actual RAW signal straight from the camera sensor,” explains Nicolas Touchard, VP Marketing, DxO Labs Image Quality Evaluation business.

At first I liked the idea, but after a brief look on the web side, the proposed metrics look to me partially wrong and partially unnecessary complicated.

I can understand the rationale behind Nokia SNR10 figure to measure sensor's low-light performance. It represents the minimum illumination to achieve SNR10 after color correction matrix (CCM) bringing sensor's colors to the standard set. Being incomplete as it is, SNR10 figure is simple to use and compare. Talking about DSLR sensors, I would complement it by SNR100 or SNR200, for example, showing the minimum illumination to get near perfect picture with standard colors. Such a simple figure is full of omissions, but it's very synthetic it terms it combines a lot of sensor parameters in a single, simple to use number.

Back to DxO approach, there is no such a good synthetic number as SNR10. It's more complex as there are few different numbers making it harder to compare. For example, what if "color depth" figure is excellent, but colors are wrong and suffer from metamerism? Talking about DR and ISO measurements, how do they compare visibility of different noises? One sensor might be dominated by nicely scattered Gaussian noise, other might have mostly row or column noise, yet another one might suffer from "salt and pepper" noise. All these noises have very different visibility.

Not that Nokia SNR10 has less problems, but at least it's much simpler and much more synthetic. So if I would propose DSLR sensor metric, I would go for SNR100 measured according to Nokia procedures.

What I liked though is the database with quite a detailed measured data. The pure measured data is really valuable. Kudos to DxO for making this openly available!

Toshiba Drives Industry to TSV

Semiconductor International's Philip Garrou presents his view on TSV technology adoption in CMOS image sensors:

“Their [sensors] pricing was in significant decline last year, so not much was expected to happen there. But then Toshiba (Tokyo) not only announced that they would be the first to put through-silicon vias (TSVs) into their CMOS image sensor to reduce the size, but that they were selling it essentially at the same price. This forced the other players to jump on the bandwagon over the next 12 months. So Samsung (Seoul, South Korea), Micron, Oki (Tokyo) — all the big players in CMOS image sensors — followed suit at a time when the price was significantly deteriorated. They did this only because Toshiba made the first move, and they had no choice but to follow.”

"Although inventory levels generally tend to serve as a moderating factor to the purchase of new devices, in the case of the new CMOS image sensor the OEMs that did not have it found that they were stuck with their inventories of non 3-D devices. Meanwhile, those who were able to acquire and use them made a considerable profit based on the architecture’s smaller form factor."

Fortnightly Patent Review

I spotted just two noteworthy applications in the last two weeks flow of more than 40 image sensor-related applications:

Micron application US20080265295 talks about making a deep red pixel in Bayer pattern, while green and blue pixels are shallower. This might be a useful idea for old simple 3T pixels, but Micron is going to apply it to 4T design. The problem with it is that essentially Micron has to optimize two different pixels in the same sensor, including dark current, image lag, full well, etc. All these are long and hard optimizations, requiring many trade-offs. Having two different pixels to optimize certainly does not help in this.

Application US20080265348 was filed by Philips in May 2005, right before the image sensor group was acquired by DALSA. It contains quite a detailed description of manufacturing steps of backside illuminated imager. It appears that Philips experimented with CMOS BSI well before the acquisition.

Kingpak Expands CIS Packaging Capacity

At the time when everybody worries about tomorrows markets, Kingpack makes a brave move and expands its image sensor packaging capacity. Digitimes reports that Kingpak Technology, a member of the Kingmax Group, has set a goal to expand its monthly capacity for image sensor packaging and testing from 2-3 million units to 4 million mark.

Sales from the CIS packaging segment account for 60-70% of Kingpak's total revenues at present, said the company. For CIS applications, Kingpak's customers include Micron, Logitech, Chicony, KYE and Quanta, Digitimes sources indicated.

Joint Yole-Chipworks Report on Toshiba TSV

The Toshibe VGA sensor ‘Through Silicon Vias’ TSV reverse engineering report, jointly published by Chipworks and Yole Developpement, analyzes the technology and economics behind Toshiba’s latest Image Sensor. The new report features three different chapters presenting a technical analysis by Chipworks and a reverse costing analysis and the TSV market perspectives by Yole.

Sony Announces 1.4um Pixel Generation

Akihabara News, Electronista report that Sony announced 12, 8 and 5MP sensors and camera modules featuring the new 1.4um pixels. As far as I was able to understand the original Sony Japan announcement, translated by Google, 1/2.5-inch IMX060PQ 12.25MP and 1/4-inch IMX045PQ 5.15MP sensors start sampling in March 2009, while 1/3.2-inch IMX046PQ 8.11MP samples are available in November 2008, that is now. IU060F 12.25MP camera module sampling begins in September 2009, while IU046F 8.11MP module sampling starts in February 2009. The modules have piezoelectric AF, F2.8 lens and 28mm and 32mm equivalent focal length for 12MP and 8MP models respectively.

Regarding the technology, Sony only tells about Cu wiring and column-parallel ADCs used in the sensors. 12MP sensor speed is 10fps at full resolution, while 5MP and 8MP ones have 15fps full resolution speed. All sensors have 1080p/30fps and 720p/30fps HD video modes (except 12MP one having only 27fps in 1080p mode and 5MP one having 60fps in 720p mode). The new 1.4um pixel sensitivity is said to be equal to one of 1.75um pixel.

The sensor's interface is 648MHz 2-lane MIPI and sub-LVDS. Supply voltage is a triple combination of 2.7V for analog, 1.2V for digital and 1.8V for interface (1.8V is probably needed to adopt sub-LVDS voltage levels).

Red color reproduction is one of the most difficult problems in small pixel design. Probably because of that Sony put a magnified inset with red color details in its sample picture from its new 12MP sensor (click on picture to enlarge):



Update: It looks like Sony Insider site has quite a complete translation of Sony Japan PR on 1.4um generation. It also has a translated table with sensor parameters:



Update #2: Here is the official Sony PR in English.

Terry Taber Becomes Kodak CTO

Yahoo: Kodak Company promoted Terry R. Taber to the position of Chief Technical Officer, effective Jan. 1, 2009. Taber, who joined Kodak in 1980, is currently the Chief Operating Officer of Kodak’s Image Sensor Solutions (ISS) business.

Prior to joining ISS almost two years ago, Taber, a Ph.D. in Organic Chemistry from Caltech, mainly dealt with silver halide side of Kodak business.

Consumers Willing to Pay for a Quality Camera in Their Phone

Centre Daily Times: The Strategy Analytics Wireless Device Lab service research, "The Camera is Still King: Consumers Willing to Pay for a Quality Camera on Their Mobile Device," shows that a quality camera is the primary mobile phone add-on for which consumers in the U.S. and Western Europe would be willing to pay--and willing to pay the most--compared to other mobile device features.

These findings are based on a survey of over 2800 wireless device owners in the US and Western Europe. "Strategy Analytics research shows that over 60% of all respondents would be willing to pay extra for a quality camera on their mobile device," commented Chris Schreiner, Senior User Experience Analyst at Strategy Analytics. "This desire for imaging features prevails across all age ranges in both regions."

SETI Took 50% Market Share in China

Digitimes sources tell that Seti's shipments of VGA image sensors for white-box handsets in China have climbed to 10M units per month. This represents about 50% of Chinese market, according to Digitimes sources. Seti achieved this by setting aggressive ASPs, bringing VGA sensors to below US$1 in June. Such a strategy puts additional pressure on Omnivision to keep its share on the Chinese market.

Tessera Q3 2008 Earnings Call

Seeking Alpha publishes Tessera Q3'08 Earnings Call transcript. Interesting quotes from the call:

Hank Nothhaft, President and CEO:

"the wafer-level packaging, wafer-level optics, and wafer-level camera, the average amount of time to get in production and revenue varies according to the nature of the licensee’s facility, their experience, and the technologies being licensed. If a licensee has an existing facility, it can take up to one and a half to two years after licensing for royalties to start. If the facility needs to be built from scratch, it takes longer, up to an additional six to nine months. For technologies like our smart optics, it can take one to one and a half years from licensing to royalties."

"In wafer-level packaging, during the third quarter, we announced the second licensee of our SHELLCASE MVP technology, AWLP, based in Seoul, Korea."

"Our first SHELLCASE MVP licensee, Nemotek, is scheduled to be sampling customers in the first quarter of 2009."

"Our first example of our technology integration comes through our product launch services, which we announced on September 22nd. These product launch services offer a combination of technology and resources from our Tel Aviv and Charlotte facilities."

Tessera Licenses SHELLCASE MVP to Qtech

Yahoo: Tessera announced today that Q Technology Limited (Qtech) has licensed Tessera’s SHELLCASE MVP wafer level TSV-based image sensor packaging technology. Qtech, based in China, manufactures compact camera modules for cell phones, notebook computers and security and protection markets.

Winbond Sells Its ISP Line to THine

Japan-based THine and Taiwan-based Winbond announced that the two companies agreed to transfer Winbond’s ISP Business to THine. The revenue of Winbond's ISP business in fiscal year 2007 was NT$323 million. Its ISPs is intended to wotk with 3MP to 5MP sensors and AF actuators for smart phones or high-end feature phones.

THine’s intends to use ISP in applications for security cameras, automotive camera systems, amusement machines as well as cell phone handsets and mobile gadgets with cameras.

Omnivision Launches 1MP Sensor for Automotive Market

Yahoo: Omnivision's OV9710 is claimed to be the first megapixel CMOS image sensor designed specifically for automotive vision and sensing systems. Megapixel sensors are the next wave in automotive vision systems, enabling the adoption of advanced forward-looking and extreme-wide angle applications. Initial interest in the OV9710 is said to be strong, and it is currently sampling with multiple automotive customers.

The OV9710 is a 1/4-inch sensor providing full-frame, sub-sampled or windowed 8-bit/10-bit images in raw RGB format via the digital video port. The sensor delivers full-frame video at 30 fps and VGA resolution at 60 fps. The OV9710 incorporates image processing functions, including: exposure control, gain control, white balance, lens correction and defective pixel correction.

The OV9710 is suitable for wide angle vision systems, such as bird's eye view applications and for advanced parking assistance systems. "Megapixel resolution is critical for extreme wide angle (greater than 160 degrees) applications, such as 360 degree view multi-camera systems, where distortion correction and image stitching is required," said Inayat Khajasha, Senior Automotive Product Marketing Manager at OmniVision. "VGA cameras simply cannot address electronic (on - or off-chip) distortion correction beyond 130 degree angles because they result in stretching and blurring the image, which can seriously compromise driver and passenger safety."

The OV9710 is currently available for sampling while mass production will be ready by the end of the second quarter of 2009.

Aptina Announces VGA Image Sensor for Security Applications

Yahoo: Aptina claims a major improvement in low light sensitivity with its new VGA SOC MT9V136 image sensor. The sensor’s image processing engine include auto white balance and auto exposure functions and lens alignment functionality for ease of manufacturing. The MT9V136 also integrates NTSC/PAL encoder for analog video and progressive scan digital output at 60fps, programmable On-Screen Display (OSD) capability, and flash interface.

The MT9V136 is sampling at this time and is scheduled to be in mass production early Q4 2008.

Official PR: Sigma Acquired Foveon

Sigma officially reported that it has acquired 100% of the stock of Foveon. Foveon will continue its sensor development operations in San Jose, CA. The acquisition of Foveon will enhance the development of new types of image sensors and create a synergistic effect with Sigma’s camera and lens business by improving the integration between the camera and sensor.

Image Sensor Market to Reach $11.7B By 2012

Yahoo: As stated by the recent report published by Global Industry Analysts, the world market for image sensors is expected to average to $11.7 billion by the year 2012. Currently the market is dominated by Asia-Pacific, Japan, and United States collectively accounting for 79.5% share as estimated in the year 2008.

The world CCD image sensors market is projected to witness declining demand, with the market value expected to deteriorate by US$369.9 million between the period 2008 to 2012. Japan and Asia-Pacific are expected to witness the steepest fall in sales during the aforementioned period. Growth in the world market is fashioned by the CMOS image sensors market, which is projected to witness strong double-digit growth rates. Global sales in this market are expected to rise by US$4,297 million between the period 2008 to 2012.

In Europe, France and Germany, together, collar over 54.2% of the image sensors market as estimated in 2008. Increased competition from China and Taiwan is resulting in falling average prices of image sensors. Adroit utilization of fully depreciated fab lines for manufacturing image sensors is enabling Asian players to offer products at competitive prices to OEMs.

20MP Mobile Imagers in 2012?

Tech-On: Ericsson AB of Sweden revealed its efforts in LTE mobile standard promotion at a press conference Nov 6, 2008. During the conference, Ericsson mentioned its concept of a future mobile terminal as "a mobile device in 2012." According to the concept, high-function terminals, in the future, will be equipped with a 12- to 20MP camera and support full HD video shooting capability.

Assuming the "2012 mobile device" has 1/3" sensor, this translates to 1.1um (12MP) or 0.8um (20MP) pixel pitch. As for 1.1um pixel, it's probably safe to assume that it will be mass produced sometime in 2012. I'm less sure about 0.8um generation. Probably Ericsson AB is more optimistic than me on the time table of the image sensor industry. One needs a real leapfrog to make 0.8um in 2012.

3D Imagers Landscape

It came to my attention there is a new 3D imaging startup in Switzerland, called Mesa Imaging. The company was founded in 2006 as a technology spin-out from CSEM (Centre Suisse d'Electronique et de Microtechnique). The imager gets 3D information using time-of-flight distance measurement principle. Infrared light from the camera's internal lighting source is reflected by objects in the scene and travels back to the camera, where its precise time of arrival is measured independently by each of the sensor pixels. A unique CCD/CMOS imager is in the heart of the camera. The sensor has a fast electronic gate and CCD-like storage area to achieve precise time measurements.

With Mesa Imaging arrival, there are 4 start-ups dealing with time-of-flight imaging. The 3 others are 3DV, Canesta and PMD. Also, Panasonic develops a CCD for 3D sensing.

The differences between all these approaches look quite subtle to me. All talk about necessity of background light suppression and all claim to solve this problem. All companies tell they are cheap enough for the mass market. I hope the 3D time of flight market is big enough to accommodate all five of them.

Rumor: Foveon Sold to Sigma

I got this rumor from two independent sources, both telling that Sigma has acquired Foveon more than three weeks ago. Right before the acquisition Foveon has laid off about a half of its staff, including VPs and CFO. Apparently, the layoff was associated with the closure of mobile image sensor project - the flagship Foveon project in the recent years.

The mobile sensor had 2.2um pixel size with 3-layered photodiodes. Its resolution was supposed to be close to 1.4um pixel, given same physical size of the sensor array. However, Foveon image processing was too heavy for the current mobile phone processors.

Foveon's foundry Dongbu used to provide excellent support, in hopes that Foveon would be successful on the huge mobile sensor market. Now, with no cellular project, the support might be downgraded, which complicates the new sensors development.

All the above are unconfirmed rumors. Like any rumors, you should take these with a grain of salt.

Tessera Talk on Imaging Challanges Goes On

Mobile Handset Design Line publishes a third part of "Image capture and processing challenges and solutions in portable designs". What I thought was the part 3 before is probably not a part of the series.

In the new part Tessera talks about how great is software enhanced optics and the new possibilties it opens, including full optical zoom with no moving parts, extended field depths, and small F-number optics for low-light environments.

Cypress Reveals Fast Sensors for Holographic Storage and Machine Vision

Yahoo: Cypress announced sampling of a 3MP 8um pixel image sensor with industry-leading digital data throughput of 13.2 Gbps. The new 3MP LUPA-3000 sensor offers a triggered and pipelined synchronous shutter with a frame rate of 485fps. The pipelined synchronous snapshot shutter allows reading one image while the next is being acquired. The sensor has 32 8-bit digital LVDS outputs, each runs at a 206 MHz pixel rate.

“The high-speed LUPA-3000 sensor opens up the holographic data storage market to our industry leading portfolio,” said Cliff Drowley, vice president of Cypress’s image sensor business unit.

Cypress also announced LUPA-1300-2-color 1.3MP sensor with 14um pixel size, pipelined synchronous shutter and 12 10-bit digital LVDS outputs having a programmable offset and gain amplifier for each channel of the LVDS outputs. Each channel runs at a 61MHz pixel rate, which results in 500fps frame rate at full resolution.

Prototype samples of the LUPA-3000 and LUPA-1300-2-color sensors are available now with production devices expected in the first quarter of 2009.

Samsung to Integrate Scalado SpeedTags

Ad Hoc News: Scalado has signed a contract with Samsung to license and integrate Scalado SpeedTags technology into Samsung future mobile multi-megapixel SOC designs featuring 3MP and above. With Aptina and Omnivision announced similar agreements some time ago Scalado SpeedTags get quite a broad support.

Arasan Offers MIPI IP

Arasan announced availability of MIPI IP blocks portfolio. Half a year ago there was a brief message about that. Now Arasan reveals much more details.

Arasan’s Camera Serial Interface CSI IP cores are compliant with MIPI CSI-2 specification 1.0 addressing all Tx/Rx requirements. Arasan’s highly configurable CSI IP cores are architected to support 1 to 4 lanes providing up to 4 Gbps throughput. They can support a variety of native host interfaces – APB, AHB, AXI, OCP, Micro-Controller or customer specific interfaces, providing seamless integration to any camera sensor or image processor. Optionally, the IP cores also support compression/decompression with predictor algorithms.

The Arasan CSI-2 IP cores are readily available and have been integrated into several customer designs.

Arasan claims it's the first on the market with MIPI IP blocks, but Mixel also announced such an IP many months ago.

Kodak CMOS Sales Start in 2H 2009

Seeking Alpha publishes Kodak Q3 2008 earning call transcript. One of the questions adresses CMOS image sensor sales targets:

Joan Lappin - Gramercy Capital:

So when do you think that significant sales of these CMOS sensors could -- I thought the original target was the second half of next year. Are we able to stick with that target as to when the CMOS sensors start to become a revenue and earnings contributor? Or must we--

Antonio Perez, CEO:

That is the target that we put for ourselves for a significant increase in volume. And that still is the target, Joan.

Joan Lappin - Gramercy Capital:

Okay. So you haven't had to -- no alterations in that.

Antonio Perez:

No.

---

To me this sounds like Joan is a bit skeptical about Kodak being able to achieve its sales target.

Pixelplus Q3 2008 Results

Yahoo: Pixelplus revenue for the Q3 of 2008 was $3.7M, compared to $3.1M in Q2 2008, and $3.9M in Q3 2007. Net loss in Q3 2008 was $2.9M, compared to a net loss of $2.3M in Q2 2008, and a net loss of $1.2M in Q3 2007. Gross margin for Q3 2008 was 15.3%, compared to 4.9% in Q2 2008.

The company sold approximately 7.4M image sensors in Q3 2008, which represents an increase of about 0.3M units from its sale of around 7.1M units in Q2 2008.

Pixelplus CEO and President S.K. Lee says: "The economic slowdown in China had a negative impact on our business in the third quarter, and this impact was much greater and broader than we had ever imagined. In response to the unprecedented financial turmoil arising from the Global Financial Crisis and the severe economic burden this has placed on the Asian economies, we continue to adapt to unfavorable market conditions."

Cypress-Fillfactory Celebrates 100th Cusom Design

Yahoo: Cypress-Fillfactory announced that it has completed its 100th custom CMOS image sensor design.

Cypress’s portfolio of applications includes industrial and medical x-ray imaging, endoscopy, machine vision, star tracking and remote sensing for space, barcode readers, biometrics, high-speed line sensors and high-speed motion analysis sensors. The company designed sensors for Vision Research, Toshiba Teli, Micro Imaging, ARRI Gmbh, along with more than forty other custom-sensor customers.

Sony Image Sensors Profit Declined

Tech-On: Sony announced its financial results for Q2 (July to September) of FY2008. Its operating income plunged 90.1% on year over year basis. Image sensors were cited as one of the fields where income declined more than the average.

ST and Vistec Reveal Their Color Filter Monitoring System

Semiconductor International: ST talks about its method for optical inline monitoring of colorization effects on CMOS image sensors in its fab.

Typical defects in the manufacturing process are streaks on the color filter array. They occur after liquid processes, mainly after resist spin-coating steps. A new, automatic and fast optical inspection method for colorization effects was developed by Vistec Semiconductor Systems in collaboration with ST. The successful detection of colorization problems became possible by using an automated macro defect inspection system (Vistec LDS3200) with a combined microscope module and special optimized analysis software. The tool scans a wafer in less than 6 minutes and delivers the inspection result for the full wafer.

Micron Imaging Business Lost $31M in FY2008

Micron just published its FY2008 10-K form. Micron confirms that Aptina already operates as a separate entity: "We are exploring partnering arrangements with outside parties regarding the separation of our Aptina Imaging business to an independent entity in which we would retain a significant minority ownership interest. To that end, we began operating our Imaging business as a separate, wholly-owned, subsidiary in October 2008."

Some noteworthy numbers reported:

• Image sensor sales were $653M, $687M and $749M in 2008, 2007 and 2006 respectively.
• Imaging products represent 11%, 12% and 14% of Micron’s total net sales in 2008, 2007 and 2006 respectively.
• Imaging operation's gross margins were 28%, 34% and 43% in 2008, 2007 and 2006 respectively.
• Imaging R&D expenses were $144M, $158M and $82M in 2008, 2007 and 2006 respectively.
• Imaging business loss was $31M in FY2008, vs income $8M in 2007 and income $153M in 2006
• Aptina quarterly loss in Q4 2008 was $4M vs Q3'08 income $3M

Melexis Announces Automotive HDR Sensor

Melexis announces MLX75307 sensor primarily intended for automotive front vision applications, like Advanced Driver Assistance Systems (ADAS), high beam assist and night vision. The 750x400 pixel sensor is said to have up to 128dB DR.

Production of the MLX75307 sensor is scheduled for 2009.

EETimes on Magnachip CIS Decision

EETimes comes with a post-mortem article on Magnachip exiting image sensor business. Nothing new is there, just re-iteration that the company is in a difficult cash position and it has no choice but to make the hard decisions.

Digitimes also repeats the same info. These reports are mostly based on Magnachip announcement of its Q3'08 results (Yahoo).

RIT Team to Develop Photon Counting Sensor

Democrat and Chronicle: Donald Figer and his colleagues at Rochester Institute of Technology got $2.8M grant to develop a light detector that would count individual photons for astronomy applications.

Current technology uses sensors that can be triggered by electronic "noise" within the electronic device itself, resulting in a grainy, speckled image, especially in low-light conditions.

"In our detector we're doing something radically different. Each photon of light is being counted," said Figer, director of the Rochester Imaging Detector Laboratory at RIT's Chester F. Carlson Center for Imaging Science.

Panasonic Develops 3D CCD Range Sensor

Tech-On: Panasonic has developed a 3D range sensor that uses a CCD and can be used at 100,000lux illumination. The range sensor irradiates a signal light on the measurement target and observes the reflected light. In extremely bright ambient light such as direct sunlight, the CCD sensor is saturated with only the ambient light, making it almost impossible to detect the signal light.

In the new sensor, the electric charge corresponding to that generated by the ambient light is removed from the charge generated in the photosensitive unit so that only the charge generated by the reflected light remains. I assume it uses some sort of fast gating to minimize the stray ambient light influence. The 3D CCD resolution is 16x120.

Varioptic Taiwan is No More

Digitimes: Varioptic is to close its Taiwan branch office, because its "liquid lens solutions are not competitive with conventional VCM (voice coil motor) auto-focus devices in terms of price, according to the branch office."

Varioptic's cooperation with Creative Sensor Incorporated (CSI), a Taiwan-based camera module maker, for volume production of liquid lenses will remain unchanged.

SMIC Begins 0.11um CIS Pilot Production

Yahoo: SMIC announces 0.11um CIS technology. The new process is available with both aluminum and copper metalization, which can be manufactured on 200mm and 300mm wafers - looks like too many options to me. SMIC says it has begun 0.11um pilot production for its customers.

Foveon Co-Founder Dick Merrill Passed Away

Dpreview Forum: Dick Merrill (1949-2008) brought to the table many of the ideas behind the Foveon X3 imager, which he co-invented with Dick Lyon, who was able to see a concept among many of Dick Merrill's patents. Together with Dick Lyon and Carver Mead, Dick Merrill was one of the founders of Foveon. In 2005, these three were awarded the Progress Medal for this work by the Royal Photographic Society of Great Britain.

Dick was a warm and wonderful person and someone who took great pleasure in his passion and the photographic images it provided. In many ways, he was the spirit within Foveon and, before that, Nat Semi.

Caltech Sues 6 Companies over CIS Patents

Pasadena Star reports that Caltech is suing Canon USA, Sony Corp., Nikon Inc., Olympus America, Panasonic Corp. and Samsung Electronics Co. for infringing on JPL-Caltech imaging patents.
In dpreview forum Eric Fossum quotes Law360 article that the six patents at issue are:

1. U.S. Patent Number 5,990,506, titled Active Pixel Sensors with Substantially Planarized Color Filtering Elements;
2. U.S. Patent Number 6,456,326, titled Single Chip Camera Having Double Sampling Operation;
3. U.S. Patent Number 6,549,235, titled Single Substrate Camera Device with CMOS Image Sensor;
4. U.S. Patent Number 6,555,842, titled Active Pixel Sensor with Intra-pixel Charge Transfer;
5. U.S. Patent Number 6,570,617, titled CMOS Active Pixel Sensor Type Imaging System on a Chip;
   
6. U.S. Patent Number 6,744,068, titled Active Pixel Sensor with Intra-pixel Charge Transfer.

New 'Avocet' CMOS Image Sensor Technology and Products from Sensata

Yahoo: Sensata got into image sensors a year and a half ago when it acquired the remains of SmalCamera from Cypress. Today Sensata announced the new Avocet HDR technology based on SmalCamera's Autobrite and now offering a dynamic range up to 154dB.

In SmalCamera's tradition to offer a complete system solution, the new technology is presented in three product configurations: a single box complete solution, Vision Systems Platform (VSP); a standard video camera for 2 box solutions; or as an imaging module for engineers building their own camera. All solution are available with monochrome, RGB or RGBi sensor versions.

The technology applications include a range of vehicle alert and avoidance systems such as night vision, lane departure warning, collision mitigation, blind spot monitoring and enhanced back-up displays.

Aptina Introduces Automotive SoC Sensor

Yahoo: Aptina announced the launch of its new multi-function automotive imaging SOC. The new MT9V126 SOC features the industry’s smallest automotive-grade (AEC-Q100) package, 0.5Lux low-light sensitivity, on-chip lens distortion correction, perspective correction and a dynamic graphic overlay capability.

The MT9V126 will be sampling in December of 2008 and will be in mass production the end of Q2 2009.

Omnivision Starts Mass Production of SoC for Automotive Applications

Yahoo: Omnivision announced that its 1/4-inch OV7710 VGA sensor is in volume production and has shipped to multiple top-tier automotive customers.

ST Announces Its First HDR Sensor

Yahoo: ST Micro announces its first automotive HDR sensor targeted for driver assistance systems. This new VL5510 sensor has a 1024x512-pixel format, suitable for wide-angle products. Its specifications include: 5.6um pixel size; sensitivity 7.14V/lux, low dark current of 33aA/pixel at 25C, and high QE at near infra-red, frame rate up to 34fps; video delivered via 12-bit parallel interface or serial interface (RAW 8/10/12 format). Anti dark sun and defect pixel correction algorithms are also integrated, together with an image histogram is embedded in the delivered image. The high dynamic response of the sensor is fully programmable: 10 knee points are available to tune pixel response.

The device is currently sampling and will be in mass production in automotive applications in early 2009. Pricing is expected to be in the range of $20 for bare-die quantities of 10,000 pieces.

TSV Rollercoaster

Philip Garrou from Semiconductor International anticipates a surge of activity in TSV and 3D integration in image sensors. He summarizes TSV activities by all the leading image sensor makers in his nice blog message from a month ago. A newer post paints a bigger picture where image sensor TSV adoption is just a first step of large scale TSV move.

Graphin Image Sensor Evaluation System

Yahoo: Japan-based Graphin announced image sensor evaluation suite with MIPI interface. Graphin has completed an evaluation for a D-PHY physical layer compliant with the MIPI standard and created a prototyping system with intellectual properties supporting CSI-2 protocol controls. Graphin is working on the MIPI Advanced Board commercially available in December 2008.

The MIPI Advanced Board is an add-on to a range of Graphin CIS evaluation systems.

SMPT Honors Albert Theuwissen

Entertainment technology innovators will be honored by the Society of Motion Picture & Television Engineers during an awards presentation at the organization's annual Tech Conference & Expo, Oct. 28-30 at the Renaissance Hotel in Hollywood.

"The Fuji Gold Medal for the design and development of techniques and equipment advancing photographic or electronic image origination will be bestowed on Dr. Albert Theuwissen, professor at Delft University of Technology and founder of Harvest Imaging, for his contributions to R&D and education in the field of solid-state image sensing."

Omnivision Secures TSMC and PSC Capacity

Digitimes reports that Omnivision is in talks with TSMC and PSC to secure wafer capacity in 2009 to help it further expand market share, according to the paper's sources in Taiwan's wafer foundry industry.

Digitimes says that Omnivision is the top vendor of image sensors in the notebook and handset segments. OmniVision is not being complacent and the company has been trying to grab as much as the global market share through capacity support from foundry companies in addition to continuing product innovation, the sources indicated.

Digitimes sources think that Aptina in its push to expand its capacity is likely to approach TSMC and PSC, as they are the two Taiwan-based foundry services companies that have more production capacity and manufacturing expertise in the production of CMOS image sensors. OmniVision aims to stymie Aptina's efforts to build up business relations with TSMC or PSC through its strengthened cooperation with the two companies, speculated the sources.

CMOSIS on Global Shutter and High DR Solutions

Guy Meynants, CEO of CMOSIS, reviews global shutter and high DR solutions for machine vision sensors in his article published by Advanced Imaging Pro.

Tessera on Camera Module Cost Reduction

Mobile Imaging Design Line publishes part three of Tessera's 4-part esse on mobile imaging (parts 1 and 2). Naturally, Wafer Level Package and Wafer Level Camera are named as the important parts of the cost reduction.

SiOnyx, The Black Silicon Company

SiOnyx is set up to commercialize the new material discovered by Harward University physicist Eric Mazur. As I understand from the company site "Black Silicon" is a modified material having a narrower than bulk Si bandgap and still compatible with Si process (not necessarily CMOS process). The narrower bandgap allows for higher absorption coefficient for visible light.

It looks like the photodetector is based on photoconductive principle, rather than photodiode, so an additional gain is possible right in the detector itself. The noise would be higher as well, both at low and strong light, but the company does not talk about this so far.

SiOnyx sees a lot of applications for the new photodetector, imaging is one of them. A white paper specifically talks about smaller than 1um pixels, leveraging higher absorption coefficient of Black Silicon.

NY Times runs an article about the new company and people behind it.

Image Sensors on 2009 Electronic Imaging Conference

The program of SPIE Electronic Imaging 2009 contains many interesting papers on image sensors. First, Industrial and Scientific Sensors and Sytems session:

Fujifilm continues its work on organic film image sensors:

CMOS-image sensor with overlaid organic-photoelectric conversion layers: development of layers with desirable spectral sensitivities
Author(s): Mikio Ihama, Tetsuro Mitsui, Takashi Goto, Kimiatsu Nomura, FUJIFILM Corp. (Japan)

French Commissariat à l'Energie Atomique presents something that sounds similar to the recent Canon color filter patent application:

Nanoplasmonic filters for image sensors
Author(s): Stephane Getin, Yohan Désières, Catherine Pellé, Olivier Lartigue, Ludovic Poupinet, Laurent Frey, Commissariat à l'Energie Atomique (France)

Yet another unusual color filter paper from the same organization:

Thin color and stop-infrared metal-dielectric filters for CMOS-image sensors
Author(s): Gilles Grand, Catherine Pellé, Laurent Frey, Norbert Moussy, Jacques Raby, Commissariat à l'Energie Atomique (France)

Global shutter is not new, so I wonder what Photron and Toshiba can say in their mutual paper:

A global electronic shutter pixel using pinned diodes fabricated in standard CMOS-image sensor technology
Author(s): Keita Yasutomi, Shoji Kawahito, Shinya Ito, Shizuoka Univ. (Japan); Toshihiro Tamura, Photron Ltd. (Japan); Masanori Furuta, Toshiba Corp. Semiconductor Co. (Japan)

Toshiba continues to perfect its 2.2um pixel generation:

Low Gr-Gb sensitivity imbalance 3.2M CMOS-image sensor with 2.2-μm pixel
Author(s): Nagataka Tanaka, Junji Naruse, Hirofumi Yamashita, Ikuko Inoue, Makoto Monoi, Toshiba Corp. (Japan)

Toshiba also perfects its CCDs:

A single-layer CCD image sensor with wide-gap electrode and gradual potential channel

Author(s): Makoto Monoi, Toshiba Corp. (Japan); Syu Sasaki, Kumiko Dobashi, Junya Iwai, Hirokazu Sekine, Iwate Toshiba Electronics Co., Ltd. (Japan); Masayuki Ooki, Seiichi Mashiko, Hiroyuki Saito, Toshiba Microelectronics Corp. (Japan); Ken Tomita, Yasushi Itabashi, Toshiba Corp. (Japan)

Aptina tells about its modeling techniques:

Computational modeling of CMOS image sensor pixels: from module lens to photoelectron
Author(s): Jeff Mackey, Victor A. Lenchenkov, William Gazeley, Xiaofeng Fan, Ulrich C. Boettiger, Gennadiy A. Agranov, Aptina Imaging (United States)

Panasonic found a way to adjust spectral response of its sensors. I hope it's something more smart than just controlling the photodiode voltage and depletion depth:

A day and night MOS imager spectrally adjusted for a wide range of color temperatures
Author(s): Koyama Shinzo, Matsushita Electric Industrial Co., Ltd. (Japan)

AWAIBA is trying to penetrate to the lucrative endoscopic market:

Minimal form factor digital-image sensor for endoscopic applications
Author(s): Martin Wäny, Stephan Voltz, Fabio Gaspar, Lei Chen, AWAIBA Lda. (Portugal)

There are few more interesting papers in the Digital Photography session:

DALSA explores large sensor trade-offs:

Very-large-area CCD image sensors: concept and cost-effective research
Author(s): Erik W. Bogaart, Inge M. Peters, Agnes C. Kleimann, Erik-Jan P. Manoury, Wilco Klaassens, Walter de Laat, DALSA Corp. (Netherlands); Cees Draijer, Raymond Frost, DALSA Corp. (Canada); Jan T. Bosiers, DALSA Corp. (Netherlands)

Big surprise - Omnivision's paper! I think this is the first time ever that Omnivision publishes a technical paper on a technical conference (marketing papers are not counted):

Decoupling light collection efficiency and color crosstalk from the Quantum Efficiency Spectrum for the CMOS image sensor pixel development
Author(s): Yang Wu, Philip J. Cizdziel, Howard E. Rhodes, OmniVision Technologies, Inc. (United States)

Aptina presents something that sounds quite interesting:

Pixel with photodiode-contained readout circuitry
Author(s): John W. Ladd, Gennadiy A. Agranov, Xiaofeng Fan, Rick Mauritzson, Zhiping Yin, Robert Gravelle, Xinya Lei, Richard D. Holscher, Aptina Imaging (United States)

Peter Catrysse from Stanford trims small microlens expectations:

Microlens performance limits in sub-2um pixel CMOS image sensors
Author(s): Yijie Huo, Christian C. Fesenmaier, Peter B. Catrysse, Stanford Univ. (United States)

There are too many interesting papers to mention. The course part has two courses for beginners by James R. Janesick, Sarnoff Corp.:

Introduction to CCD and CMOS Imaging Sensors and Applications

Digital Camera and Sensor Evaluation Using Photon Transfer

Thanks to A.T. for keeping me updated on that.