Chipworks Shows Phase AF Pixels in Canon DSLR

Chipworks published a teardown report of the new Canon EOS 650D – Rebel T4i DSLR. Its LC1270 sensor uses phase detection for quick auto-focusing.

Phase detection is where there are pairs of sensors that are blocked left and right (or top and bottom) and from the differences, the camera has the information needed to bring the image into focus:

IR image of the pixel array

Chipworks first analyzed this type of technology in the Nikon V1 with an Aptina sensor MT9J007. Aptina used a set of 9 regular lines of phase AF pixels, while Canon is using a somewhat irregular pixel pattern for phase detection:

Canon patent US 2010/0165176 has a fairly detailed description of their approach.

Polight Lens Supported by Driver Chip from Semtech

Business Wire: Polight TLens apparently needs driving voltage in range of -16V to 30V. Semtech SX8750 single-chip charge pump makes this voltage out of 2.65-3.6V supply with no external inductors or flying capacitors.

Christian Dupont, CEO of poLight, said, "Besides the integrated charge pump that provides sufficient voltage to activate the TLens, Semtech’s driver’s main features are its small size, low power and optimized performance, which are essential factors when combined with poLight TLens."

The SX8750 is sampling now and will be available in September in production quantities of 3,000-piece lots.

The driver's feature list:

• 2.65 - 3.6 V supply, -16 V to +30 V differential output
• Low power with less than 5mW averaged in active mode and with 1 uA listen mode current consumption
• Small form factor: CSP 0.8x1.6x0.5mm
• No coil or flying capacitor required for minimal total solution area
• I2C controlled 10 bit differential DAC for precise focus
• Low Interference thanks to lowest current consumption
• Allows for 1 ms settling time with TLens

Temporal Noise in the Dark

Albert Theuwissen continues his article on temporal noise in the dark measurements. The thirs part covers row temporal noise over the exposure range.

Sony Pitches its Shareholders over Stacked Sensors

Sony annual report has a special section on stacked image sensors. The stacked sensors are presented as the next evolution step, right after BSI:

Sony says "it focuses on introducing an era of “Super Reality” surpassing human vision, Sony will continue to lead the digital imaging world by ensuring the industry´s highest quality and most advance."

The first picture of a stacked sensor in comparison with other Sony products:

A nice graph showing Sony capacity expansion and future plans:

And two nice market size graphs:

Another Sony annual report pitch is the expanding the world of 4K video.

Update: As Imaging Resource reports, Olympus uses Sony sensor in its OM-D E-M5 DSLR - says something about Sony market adoption.

Will CCDs Survive?

DALSA blog post called "Are All CCDs Dinosaurs?" discusses the future of CCDs. The post author Nixon believes that one niche where CCDs are superior to CMOS is noiseless TDI: "so like the dinosaurs that survived the great meteor impact (which many now call “birds”), I am betting that CCD TDIs will stick around for quite a while."

Invisage's Short Videos

Invisage published two short videos on Youtube. The first one is titled "InVisage's QuantumFilm enables more compact lenses because of our top surface architecture." The company explains: "Traditional CMOS sensors are not top surface detectors so accommodating shorter lenses create crosstalk and thus, noise. QuantumFilm image sensors enable more compact lenses because our top surface architecture can accept light ray angles that are much steeper. This means shorter lenses can be used without any degradation in performance:"



The second video demos "InVisage's InstantShutter: A true global electronic that obviates the need for mechanical shutters." The video description says: "The problem is CMOS image sensors can only expose & read lines of pixels at any one point, instead of a full frame. This leads to what is now known as the rolling shutter effect or "jello" effect. InVisage's InstantShutter truly is a breakthrough because of its ability to snap an entire frame, each and every pixel, at the exact same time instant:"

Eedoo Sales Disappoint

Kotaku: The Lenovo backed company eedoo, the maker of China's Kinect-like gesture recognition game console, the CT-510, has fired their head of marketing over dismal first month sales.

According to Chinese-language Tencent games news channel, the CT-510, which has been out since late May, has had terrible sales mostly due to the lack of advertising, marketing and its exorbitant $600 price tag.

Tencent also reports that while eedoo was able to attain funding for their initial launch they have been having problems drumming up extra funding. As it looks right now eedoo maybe facing some problems other than just financing. Reports from the State Intellectual Property Office also show that eedoo's claims of having mostly proprietary technology in their CT-510 to be a farce.

TI Creates Thz-band Emitter in 45nm Process

EETimes: TI has demonstrated an essential element of THz imaging - a single-chip emitter created in cooperation with Texas Analog Center of Excellence at the University of Texas at Dallas. TI's terahertz-range emitter uses a multiplying PLL with two frequency dividers in the feedback loop to create 390GHz frequency. The power emanating from the on-chip antenna was 2.2 uW.

The world's first CMOS PLL-based terahertz emitter in 45-nm process
with on-chip antenna.

"The FCC defines the terahertz range to be from 300 GHz to 3 THz," said Eunyoung Seok, a design engineer at TI's Kilby Labs. "For the future, we want to use TI's 45-nanometer process to cover more of this wider frequency range, as well as to increase our output power." The researchers believe that improvements will enable the CMOS emitter to reach 600 GHz or higher.

CMOSIS 12MP/150fps GS Sensor Enters Mass Production

Electronics Weekly: CMOSIS announces its 12MP/150fps CMV12000 enters mass production. It's 5.5um GS pixels use CMOSIS proprietary 8T architecture. The peak QE is claimed to be more than 60% resulting in 4.64V/lux.s response in combination with DR of 60dB. Operating temperature range of the 143pin PGA device is -30 to +70°C, and both monochrome and RGB variants are in production today.

At full 150fps speed, full pixel resolution, and 10bit ADC resolution, the 64 LVDS outputs are running at 300Mbit/s each, and power dissipation is 3W.

CMV12000 was first announced in November 2010 and at that time was aimed to deliver 300fps at 10-bit ADC resolution or 180fps in 12-bit ADC mode.

Omnivision's Dual Conversion Gain and FD Boosting Application

Omnivision patent application US20120153123 presents dual conversion gain pixel with a possibility of FD voltage boost. A prior art dual conversion gain pixel just adds a cap on FD like this:

Omnivision proposes to connect the cap from outside of the array, like that:

The low CG setting can be made even lower by adding -G amp, like shown below:

Once we are at column amplifiers, one obvious improvement is to add a positive gain amp for the high CG setting, so that the effective FD capacitance would be reduced by a weak positive feedback. For some reason the application does not mention this option.

The added capacitor also allows to boost FD potential to (over)compensate the charge injection and control feedthrough when RST gate turns off (the first figure is prior art, the second one is improvement):