Wednesday, March 31, 2021

EMVA 1288 v.4 General Release Says Goodbye to Photon Transfer Curve

IMVEEMVA 1288 publishes 4.0 release candidate of the standard. The main difference from the circa 2016 version 3.1 is the split into linear and general documents:

"Starting with Release 4, the EMVA 1288 standard includes two separate documents. The separate document describes Release 4 Linear and is a direct successor of Release 3.1 with a few changes and extensions. Release 4 Linear, as the name says, is limited to cameras and image sensors with a linear characteristic curve. Together with the photon transfer curve, the basic mean parameters temporal dark noise, system gain and quantum efficiencies can be determined.

This document Release 4 General can be used for much wider classes of cameras and image sensors. It no longer relies on a linear characteristic curve or that raw data are provided. The photon transfer curve is no longer used. The essential point is that basically the same measurements are performed, but they are analyzed in a different way providing still all important application relevant parameters.

While the previous releases of the standard focused on monochrome cameras with a single channel and additionally only included color cameras, Release 4 takes into account the significant advance of multimodal imaging, including polarization, multispectral and time-of-flight (depth imaging). Each of these multimodal sensors includes multiple channels.

If the raw data from these channels is available, each channel can be characterized with EMVA 1288 measurements. Polarization imaging serves as a model how the rich tool set of the standard can also be applied to parameters, computed from several channels, here the degree of polarization and the angle of (partially) polarized light."

Intevac's Vacuum SWIR Sensor, BusinessWire: Intevac has received a $1.8M development contract award from the Joint Directed Energy Transition Office (DE JTO) in Albuquerque New Mexico, representing the funding for year one of a projected three-year, $7M development effort. In this program, Intevac Photonics will develop a Gated SWIR Sensor for High Energy Laser (HEL) 2D Fine Tracking and Adaptive Optics system applications.

BusinessWire: Earlier, Itevac has developed a LIVAR M506 SWIR night vision version of its EBAPS sensor for defense applications:

Yole CIS Market Update

Yole Developpement publishes an updated report on CIS market:

"In 2020 the segment was worth $20.7B, exceeding 4.7% of total semiconductor industry sales. This segment has made Sony a significant semiconductor player, alongside other CIS players such as Samsung, OmniVision, and STMicroelectronics."

Tuesday, March 30, 2021

Exotic Photodetectors News

The papers below promise to revolutionize future image sensor technology in many different ways. Whether you believe it or not is up to you.

OSA publishes Tianjin University, China, paper "Low operating voltage monolithic stacked perovskite photodetectors for imaging applications" by Hongliang Zhao, Tengteng Li, Qingyan Li, Chengqi Ma, Jie Li, Chenglong Zheng, Yating Zhang, and Jianquan Yao.

"The monolithic stacked design is expected to solve the challenges of wiring difficulties, complex fabrication processes, and low resolution. However, a photodetector array with low operating voltage that is suitable for imaging applications has not been proposed. Here, a perovskite photodetector array with a monolithic stacked structure is proposed. The CH3NH3PbI3 photodetector has a low power consumption off-state (0 V) and on-state (−2 V) voltage, and the highest responsivity and specific detectivity of 0.39 A/W and 4.53e12 Jones at 775 nm, respectively. The rise time and decay time are 111 µs and 250 µs respectively. In addition, the imaging application shows high contrast, which provides a simple and effective way to prepare high performance perovskite imaging devices."

Science Magazine publishes North Carolina State University and KAIS paper "Mantis shrimp–inspired organic photodetector for simultaneous hyperspectral and polarimetric imaging" by Ali Altaqui, Pratik Sen, Harry Schrickx, Jeromy Rech, Jin-Woo Lee, Michael Escuti, Wei You, Bumjoon J. Kim, Robert Kolbas, Brendan T. O’Connor, and Michael Kudenov.

"Combining hyperspectral and polarimetric imaging provides a powerful sensing modality with broad applications from astronomy to biology. Existing methods rely on temporal data acquisition or snapshot imaging of spatially separated detectors. These approaches incur fundamental artifacts that degrade imaging performance. To overcome these limitations, we present a stomatopod-inspired sensor capable of snapshot hyperspectral and polarization sensing in a single pixel. The design consists of stacking polarization-sensitive organic photovoltaics (P-OPVs) and polymer retarders. Multiple spectral and polarization channels are obtained by exploiting the P-OPVs’ anisotropic response and the retarders’ dispersion. We show that the design can sense 15 spectral channels over a 350-nanometer bandwidth. A detector is also experimentally demonstrated, which simultaneously registers four spectral channels and three polarization channels. The sensor showcases the myriad degrees of freedom offered by organic semiconductors that are not available in inorganics and heralds a fundamentally unexplored route for simultaneous spectral and polarimetric imaging."

Sandia Labs publishes a research "Design of High-Performance Photon-Number-Resolving Photodetectors Based on Coherently Interacting Nanoscale Elements" by Steve M. Young, Mohan Sarovar, and François Léonard.

"In summary, we employed a fundamental approach based on quantum master equations to identify the challenges in high performance photon number resolving photodetectors. A number of obstructions arise when attempting to achieve PNR (Photon Number Resolving) while simultaneously optimizing important metrics. Using our approach we are able to understand the reasons for these obstructions and formulate designs that circumvent them. As a result, we designed a novel detector architecture based on coherently and collectively interacting absorbing elements, energy transfer, and a continuous monitoring process, that is able to achieve PNR as well as excellent performance in terms of efficiency, dark counts, bandwidth, and count rate. The needed physical properties of this architecture suggest that molecular and nanoscale systems are prime candidates to realize new generations of photodetectors."

Applied Physics Letters publishes a paper "Monolithic infrared silicon photonics: The rise of (Si)GeSn semiconductors" by O. Moutanabbir,  S. Assali,  X. Gong,  E. O'Reilly,  C. A. Broderick,  B. Marzban,  J. Witzens,  W. Du, S-Q. Yu,  A. Chelnokov,  D. Buca, and  D. Nam from École Polytechnique de Montréal, National University of Singapore, University College Cork,  RWTH Aachen University, Wilkes University, University of Arkansas, University Grenoble Alpes, Peter Gruenberg Institute, and Nanyang Technological University.

"(Si)GeSn semiconductors are finally coming of age after a long gestation period. The demonstration of device-quality epi-layers and quantum-engineered heterostructures has meant that tunable all-group IV Si-integrated infrared photonics is now a real possibility. Notwithstanding the recent exciting developments in (Si)GeSn materials and devices, this family of semiconductors is still facing serious limitations that need to be addressed to enable reliable and scalable applications. The main outstanding challenges include the difficulty to grow high-crystalline quality layers and heterostructures at the desired content and lattice strain, preserve the material integrity during growth and throughout device processing steps, and control doping and defect density. Other challenges are related to the lack of optimized device designs and predictive theoretical models to evaluate and simulate the fundamental properties and performance of (Si)GeSn layers and heterostructures. This Perspective highlights key strategies to circumvent these hurdles and hopefully bring this material system to maturity to create far-reaching opportunities for Si-compatible infrared photodetectors, sensors, and emitters for applications in free-space communication, infrared harvesting, biological and chemical sensing, and thermal imaging."

Infineon Posts Chart Explaining ToF Camera Design Tasks

Infineon publishes a chart explaining 3D camera design tasks beyond a ToF sensor:

NHK Presentation on 8K Organic Sensor Camera

NHK presented its organic image sensor-based camera for 8K TV broadcast (2019 presentation):

For those of you with IEEE SSCS account access, there is also Panasonic webinar by Kazuko Nishimura on organic image sensor.

Monday, March 29, 2021

Canon Presents X-Ray Sensor With Auto-Exposure Control

Canon announces the new "Built-in AEC assistance" technology for digital radiography. With this technology, the device's X-ray image sensor uses real-time detection of the pixel value corresponding to emitted X-rays, notifying the X-ray generator when pixel value reaches a preset value.

In clinical environments, X-ray imaging is conducted with various precautions in accordance with the ALARA (As Low As Reasonably Achievable) principle of radiation safety, which states that the use of radiation must, among other factors, "take into account benefits to the public health and safety, and other societal and socioeconomic considerations." The AEC technology enables operators to specify a pixel value and automatically send a notification to the X-ray generator. When that value is reached, eliminating the need for a dedicated external attachment and enabling the automatic stopping of X-ray emissions from the X-ray generator.

Samsung Presents AI-based Bad Pixel Detection

Springer publishes a Samsung paper presented at 2020 International Conference on Computer Vision and Image Processing "A Pre-processing Assisted Neural Network for Dynamic Bad Pixel Detection in Bayer Images" by Girish Kalyanasundaram, Puneet Pandey, and Manjit Hota.

"CMOS image sensor cameras are integral part of modern hand held devices. Traditionally, CMOS image sensors are affected by many types of noises which reduce the quality of image generated. These spatially and temporally varying noises alter the pixel intensities, leading to corrupted pixels, also known as “bad” pixels. The proposed method uses a simple neural network approach to detect such bad pixels on a Bayer sensor image so that it can be corrected and overall image quality can be improved. The results show that we are able to achieve a defect miss rate of less than 0.045% with the proposed method."

Sunday, March 28, 2021

ISSCC 2021 On-Line: Samsung ISOCELL Vizion 33D Paper

 Samsung ISOCELL Vizion presentation at ISSCC 2021 details the company iToF approach: "7.1 - A 4-tap 3.5μm 1.2Mpixel Indirect Time-of-Flight CMOS Image Sensor with Peak Current Mitigation and Multi-User Interference Cancellation" by Min-Sun Keel, Daeyun Kim, Yeomyung Kim, Myunghan Bae, Myoungoh Ki, Bumsik Chung, Sooho Son, Hoyong Lee, Heeyoung Jo, Seung-Chul Shin, Sunjoo Hong, Jaeil An, Yonghun Kwon, Sungyoung Seo, Sunghyuck Cho, Youngchan Kim, Young-Gu Jin, Youngsun Oh, Yitae Kim, JungChak Ahn, Kyoungmin Koh, and Yongin Park.

I'm not sure what 33D means in the presentation:

Saturday, March 27, 2021

ISSCC 2021 On-Line: Sony Sensor with Integrated AI Processor

Sony ISSCC presentation "9.6 - A 1/2.3inch 12.3Mpixel with On-Chip 4.97TOPS/W CNN Processor Back-Illuminated Stacked CMOS Image Sensor" by Ryoji Eki, Satoshi Yamada, Hiroyuki Ozawa, Hitoshi Kai, Kazuyuki Okuike, Hareesh Gowtham, Hidetomo Nakanishi, Edan Almog, Yoel Livne, Gadi Yuval, Eli Zyss, and Takashi Izawa explains the trade-offs of such a product: