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Strategy Analytics publishes its GPU Technology Conference 2015 presentation "Vision-Based ADAS: Seeing the Way Forward" by Ian Riches. Few interesting statements:


Other ADAS-related presentations at the conference:

Audi driverless car presentation "zFAS the Brain of piloted Driving and Parking" by Matthias Rudolph.
Nvidia presentation "Visualizing a Car's Camera System" by Gernot Ziegler.

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Singapore-based Cogenda TCAD vendor presents a solution for pixel simulation, shown below for a simple 3T pixel:


The company's Youtube channel shows the TCAD simulator in action.

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Business Wire: Toshiba starts commercial production of T4K82, a 13MP, 1.12um BSI pixel sensor announced a year ago that allows smartphones and tablets to record full HD video at 240 equivalent fps, said to be the industry’s highest frame rate. Commercial shipments start today.

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Digitimes: Image sensor packaging house Xintec plance to have its 12-inch WLCSP production line ready 2H 2015. Xintec started to invest in its 12-inch WLP-CSP production capability in Q4 2014. TSMC holds an about 40% stake in Xintec. Orders placed by TSMC contribute about 35% to Xintec's overall revenues at present, followed by orders from OmniVision with 29%, according to Digitimes sources.

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Marketwired: Ziptronix announces a patent licensing agreement with Sony for application in advanced image sensors. The agreement is a continuation of the previous ZiBond agreement extended to Ziptronix's new DBI hybrid bonding patents for high volume applications.

"This license agreement with Sony is an exciting milestone for Ziptronix because it removes any doubt that our patented DBI hybrid bonding technology is both manufacturable and beneficial for high volume applications," noted Dan Donabedian, CEO and president of Ziptronix. "We believe it demonstrates that our patented hybrid bonding technology is both enabling and cost effective as compared to stacking with TSVs. Sony licensed Ziptronix's ZiBond direct bonding patents in 2011, which we also believe grew their image sensor market share from a few percent to the largest market share in the industry. We expect this new license for Ziptronix's DBI hybrid bonding patents will further contribute to Sony's growth within the industry. Any company wishing to compete in this space will need Ziptronix's DBI hybrid bonding patents."

DBI Fact Sheet lists the technology's features:

• Interconnect pitch ≤10µm
• Accommodates 1.5M connections/cm2
• No adhesives, solders, pressure, underfill or wire bonding required to bond and connect layers of active devices
• Uses standard fab tools and processes
• Highest reliability of all 3D processes because of hermetic sealing
• Accommodates face-to-face architectures (top die/wafer upside down)
• Accommodates face-to-back architectures (use of through-die vias/buried contacts)

Ziptronix DBI page says:

"DBI can achieve over 100,000,000 electrical connections per square centimeter; a significant increase over the ~ 100,000 connections per square centimeter density achieved with through-die vias used in other 3D interconnect approaches."


A Youtube video shows how it works:

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Business Wire: Teradyne announced the IP750Ex-HD testers to increase the parallel test capability for both wafer and final test of image sensors using new, High Density (HD) instruments. These instruments are also compatible with over 4,000 installed J750 and IP750 test systems providing added flexibility to test system operators.

New IP750Ex-HD capabilities include:

• HSD800 Multifunction Instrument. A third generation digital instrument providing 128 high speed digital channels, scalable to 2,048 channels per system.
• ICMD. A new LVDS image capture instrument supporting MIPI CSI-2 D-PHY 1.5Gbps speed at 1,2,4 Data Lane CIS and Serial 1 to 16 Lane protocol support capability. This second generation instrument has 24 differential input pairs and 128M pixel capture memory .
• IG-XL 3.60 Software.
• Zero-footprint, Air-cooled System.

"The IP750Ex-HD uses the same HD instruments as the J750Ex-HD, which has a large installed base and TAM, providing the flexibility in manufacturing to tackle a broad range of SOC and Image Sensor devices. Adding an additional Image Capture Instrument chassis also increases the ICMD slots and allows the IP750Ex-HD to expand to higher site counts," said Jason Zee, General Manager of Teradyne's Consumer Business Unit. Teradyne has received multiple orders from multiple customers and began shipments of the IP750Ex-HD systems in the fourth quarter of 2014.

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Chipworks reverse engineers Sony 2nd generation stacked sensor, the 13MP, 1.12um pixel IMX214, first announced about a year ago.

The main features of this stacked BSI device when compared to the respective features on the first generation stacked CIS are:

1. refinement and modifications to the TSVs used to connect CIS signals to the ISP circuitry
2. simplification of the manufacturing process to enable lower cost of manufacturing
3. moving of most of the circuitry from the CIS die to the ISP die, d) changes in pixel circuitry for SME functionality
4. changes in the organic layer stack on the light receiving side of CIS to bring microlenses closer to the pixel cathodes.

IMX214 bottom (logic) die

But the most intriguing part of the report is a small transformer somewhere on the chip:


If vias can be an indication of the transformer size, its inductance appears to be well below 100pH. Such inductors are not very useful at frequencies below 10GHz. I wonder why does Sony need it?

Update: Chipworks says that transformer part is just a generic marketing image, not related to IMX214 circuitry. The report flyer will be modified soon and the transformer image will be removed.

Another Chipworks report covers 28.2MP Samsung DSLR BSI sensor S5KVB2XX09, featuring 3.6um pixels. The highlights of this report are:

• Samsung is the first to market with a back-illuminated APS-C format CMOS image sensor
• An array of partially masked pixel pairs is embedded in the active pixel array to facilitate the phase-detection AF functionality
• A new shared-pixel architecture is employed for the active pixel array

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PRNewswire: Dual Aperture International ("DAI") announces a strategic partnership with SK Telecom ("SKT") in a development of DAI's 3D camera technology based on dual aperture 4-color (RGB-IR) sensors. SKT becomes a strategic investor and partner to DAI alongside a $1.4M investment, joining the previously closed $5.7M Series A funding round led by Korean venture capital fund Value Invest Korea.

SKT will develop applications and additional use cases for DAI's 3D image capture, virtual reality and image enhancement technologies. Prof. Chong-Min Kyung, CTO of DAI, commented that, "SKT is a global technology leader with the size and expertise to accelerate DAI's product implementation into global industries spanning mobile, medical, security and automotives. Korea already has a strong technological position in these growing industries, and the partnership between SKT and DAI will only further improve Korea's ability to provide innovative technologies and solutions to these markets."

In Korea, DAI will continue to refine its own technology while SKT will help define new applications for 3D cameras. In the US, DAI and SK Telecom Americas (SKTA) will jointly set up a consumer applications development lab under SKTA's Innopartners program in order to recruit innovators to develop new 3D, virtual reality, image related applications for various markets including Mobile, Medical, Security and Automobile applications.

DAI will also collaborate with Daejeon Creative Economy Innovation Center of the Ministry of Science, ICT and Future Planning, in actively looking for technologies and patents to foster globally competitive start-ups.

Dual Apertures technology is presented in its patent here.

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Sony reports its quarterly results for the quarter ended on Jan 31, 2014. Essentially, the report confirms the company's Feb. 2015 forecast for the image sensor sales:


Sony earnings release says on Devices segment results: "Sales increased 38.6% year-on-year (a 26% increase on a constant currency basis) to 292.9 billion yen (2,421 million U.S. dollars). This significant increase was primarily due to a significant increase in sales of image sensors reflecting higher demand for mobile products, the favorable impact of foreign exchange rates, as well as a significant increase in sales of camera modules. Sales to external customers increased 47.2% year-on-year."

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CMOSIS is to start sampling low-cost versions of its global shutter CMV2000 (2.2MP/340fps) and CMV4000 (4.2MP/180fps) imagers in May 2015. The new versions differentiate from their CMV equivalents by their IC package, being LCC (Leadless Ceramic Carrier) instead of µPGA. The company is to offer the CMV2000/ CMV4000 imagers at about half the price of the current µPGA versions for volumes over 5000 pcs/year. Besides being lower priced, the LCC-type package offers the additional benefit of surface mount assembly, allowing more compact cameras designs and more economical camera assembly.

"We are delighted to explore new and highly attractive market segments for our proven state-of-the-art CMV product line", said Lou Hermans, COO of CMOSIS. "The LCC packaging format will open up a host of high-volume applications and further broaden our strong worldwide position and customer base for advanced camera designs."

CMOSIS sensor in the new package

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One of the biggest European machine vision camera vendors, Stemmer Imaging, posts a Q&A session with Mark Williamson, its Director of Corporate Market Development, on Sony decision to discontinue CCD products. Generally, Mark agrees that CCD era is over, although "The importance of the CCD to mankind was recognized by a Nobel prize in Physics in 2009. In the last few years there has been a big shift from CCD to CMOS in these high volume markets which has left the CCD wafer line very underutilized even with the high number of machine vision sensors sold. This makes the factory no longer financially viable."

Other quotes:

"In 2010, 22% of cameras we sold were based on CMOS sensors. This has risen to 58% in 2014 with 32% of cameras using Sony CCDs and the remainder other high end CCDs. With nearly all new camera designs using CMOS the prediction is that in a further 4 years the natural shift would make the CMOS market share approximately 80%."

"The higher end CCDs from ON Semiconductor (formerly Truesense and Kodak) and the full frame CCDs used in professional photography from Teledyne DALSA are still available for high end applications although over time CMOS will affect this market segment also."

IMV Europe too publishes an article on the Sony CCD news, mostly quoting machine vision camera vendors reports.

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When Sony curved sensors were presented on summer 2014, there were concerns about their compatibility with zoom lens. Palo Alto, CA-based Optiz proposes a solution. The company believes that curved sensors will be the next big wave in mobile imaging:


Optiz does not say much about the principle of its approach, other than usual marketing words:

"Optiz's proprietary Zoom solution realizes Zoom function in the mobile imaging system without the drawback of conventional solutions."

"Optiz's proprietary pixel architecture technology includes pixel pattern design, photodiode structure and advanced imaging algorithms. With inventive thinking, we have re-imagined these three crucial aspects of the pixel technology and made great advancements in zooming, luminance and color accuracy. All doing so without creating additional complexity to the imaging system while enabling zoom function and reduce module size."

"Our innovative solution offers an optical interface structure that is built into the image sensor chip, thus imaging system need fewer lenses, simplifies the overall optical design and improves image quality."

"Optiz's Zoom solution offers a set of proprietary technology to enable greater sensitivity, lower module profile, superior zooming and dynamic focusing capabilities all without moving parts."

"The innovative pixel architecture provides significant advantages such as reduced cross talk between the pixels at the periphery of the sensor, substantial improvement of Quantum efficiency."

The company has been founded by Vage Oganesian, former Tessera VP R&D, and Wang Wei, CEO of WLCSP. Few pictures from the company site might give some hints on its technology:


Update: I received an email from Optiz saying:

"In regards to the comments on the blog post. We want to clarify that our curved sensor with varying size photodetector does not require physical bending/deformation of the image sensor. We took a conceptually different approach in obtaining the curved structure of image sensor during the fabrication process; So that our image sensor can remain stackable as most of the commercial BSI sensors of today."

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Belgian economics newspaper Trends.be names CMOSIS as one of the fastest growing companies in Antwerp, Belgium. Google translates:

"In medium businesses CMOSIS is the fastest growing. The company develops and produces image sensors for industrial, scientific and medical applications. Think of image chips for aerospace and sensors for the cameras from Leica. Also in the cameras for speed checks on Belgian roads are sensors CMOSIS. However, 99% of sales come from exports, with Germany, France, Italy, Japan, Korea, China, the US and Canada as key markets.

Sales in 2009 amounted to 1.9 million euros. In 2013 it was already 36 million, and 2014 ended with 53 million euros. "We are in a growth market - the number of cameras in our visual society will only increase," says CEO Luc De Mey that surge. "We also have as a niche player on highly sophisticated and well-patented technology, our sensors have a high image quality and a very large number of frames per second."

Since January 2014, the US investment firm TA Associates, 80% of the shares, the remaining 20% ​​is in the six founders, who are all active in the business. "As long as it goes well, we can go our own way." CMOSIS has 110 people on the payroll, including 75 in Berchem, the rest in the branches in Germany and Portugal. "The growth of our company is limited by the number of people we can find with expertise in this specialized field."

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PR Newswire: XMC, a Wuhan, China-based 300mm wafer foundry, announces it has shipped over 100 million BSI CMOS image sensor units. All of the BSI CIS units are high end products ranging from 5MP to 23MP by using wafer bonding technology. In addition, the state of the art 3D wafer stacking technology developed by XMC for BSI CIS has also entered volume production now. It is said to indicate that XMC has become one of the leading BSI CIS and 3D IC manufacturing companies in the world.

The R&D of wafer-level BSI technology started in the second half of 2012. It took over one year of joint effort with an unnamed XMC's partner to reach mass production at the beginning of 2014. A year later, the more advanced 3D wafer stacking, based on the BSI technology, has also been successfully developed.

"With the offering of the advanced wafer stacking technology, XMC enables its partners to enlarge the share of high-end CIS market," Shaoning Mei, CTO at XMC said, "We will further enhance our 3D IC expertise on the basis of 3D wafer stacking technology, by which we can achieve high performance and low power through directly connecting the core parts of two chips. 3D IC is expected to be an important technology to keep us on track with Moore's Law. It is also the key strength for XMC to establish its leadership in 3D IC industry."

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In the wake of CCD discontinuation news, Adimec blog starts a series of posts comparing them with CMOS sensors. Adimec looks at QE/Read Noise metric and notes that today's CMOS sensors became better than CCDs, while in a similar 2011 comparison, CCDs were the winner:

QE/RN in 2011

QE/RN in 2015

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Rambus: Tom’s Hardware announces that Rambus lensless smart sensors (LSS) won the “Best Of” (hardware) award for Mobile World Congress 2015, the second year in a row.

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Unispectral, Israel, Tel Aviv University-originated startup proposes to move sequential color imaging into camera modules. The claim is that switching Bayer filter for a sequential design increases the camera resolution by a factor of 4, and the low light sensitivity by a factor of 2. These claims are presented in Optics Express paper "Sequential filtering for color image acquisition" by Ariel Raz and David Mendlovic. (David Mendlovic used to be the manager of Tessera camera module design and now serves as CEO of Corephotonics.)

Vimeo video shows the new company's promise:



Older project info at Tel Aviv University site says that they use a tunable filter for the sequential imaging and that "Comparing with a Bayer scheme, for green the sensor provides 2 times more resolution, and for red and blue 4 times more resolution."

Thanks to WRWWCTB for the pointer!

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Mike Electric publishes a Youtube video full of FLIR Lepton imager microphotographs:



Meanwhile, FLIR Lepton family has grown to 3 different modules:

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i-Micronews: Yole Developpement publishes an interview with Yasuhiro Ueda, SVP Corporate Executive, Senior General Manager of the Image Sensor Business Division at Sony. There are quite a few interesting points there. Few quotes:

Yole: Sony was a leader in the charge-coupled device (CCD) legacy technology and succeeded in the transition to CMOS, becoming the undisputed leader in 2014. Could you explain how Sony, as an image sensor company, has succeeded in beating the odds of disruption and did not end up like Kodak, IBM, or Nokia?

Yasuhiro Ueda: The book “Innovator’s Dilemma” describes how disruptive technologies impacted the disk drive industry and how existing players unable to properly adopt the transition fell behind. This may have been the case for the companies you mentioned. In addition the book also describes how technologies can be among the extended lines of product evolution. We didn’t position CMOS image sensors as a revolutionary, disruptive, product totally different to CCDs but instead found them to be among the extended lines of our CCD evolution. Transition necessities in CCD were led by our customer’s needs for taking high definition videos. CCD works fine handling 480p SD resolution videos but higher speed HD is difficult. As a sensor division it was then just a matter of course to consider our transition to CMOS sensors, as they have much greater speed advantages. We didn’t position this move as anything innovative as the evolution was a process driven by our customers’ needs.

Yole: How do you see the overall evolution of the industry in areas such as M&A and the business models of the players? How do you see the consolidation of the industry? 2014 has been a very important year with much consolidation. Is Sony interested in taking part in it?

Yasuhiro Ueda: When we see the players they all have different roles in the market and from this point of view we don’t think there will be a necessity for further consolidation. Having said we find there are too many module makers today and we feel this is where the need to consolidate will arise.

Source: Status of the CIS industry 2015 report, Yole, Feb 2015

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Rambus, along with partners MLove and IXDS, hosted “Eyes of the IoT” MWC 2015 workshop in Barcelona, Spain, devoted to brainstorming on the possible uses of lensless image sensors. Some suggestions:

"Lars Stalling of Telefonica/Canoe Lab – who headed the smart transport group – suggested LSS technology could be used to help pedestrians navigate crowded cities like Barcelona and New York by introducing a wearable third eye."

Harald Neidhardt of MLove proposed “Lensless smart sensors [which are approximately the size of a human hair], are small enough to be painted on city walls and street signs to supplement existing safety requirements and help make true intelligent lighting a reality. We call this concept 'City Glaze'.”

Reto Wettach of IXDS said “We’re thinking about enabling ultra-smart appliances such as a refrigerator that is capable of sensing what groceries need to be ordered and what food items are close to their expiration date. LSS is inexpensive, low-powered and small enough to make it the right technology to bring intelligent appliances to the next level.”

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ON Semi Analyst Day presentation dated by Feb. 26, 2015 discusses its image sensors strategy:

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International Image Sensors Workshop 2015 pre-registration is open now. Registration is limited to approximately 150 attendees on a first-come, first-served basis. Registration will be guaranteed for presenters, but they are still required to register. Past experience shows that registration is often filled to capacity within a few days’ time.

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Xilinx demos its SDSoC Design Environment promising a quick path from C++ algorithms to FPGA hardware:

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Courthouse News Service: A federal judge preliminary approved a $12.5M class settlement that claims that OmniVision misled shareholders into believing it had an exclusive contract related to the Apple iPhone 4. Shareholders claimed that the company CFO Anson Chan made false and misleading statements about the technological advantages of its image sensor versus its competitors', and its competitive position with customers such as Apple. These misrepresentations deceived the market into believing that OmniVision was maintaining its exclusive position as the supplier of image sensors for iPhone 4, causing Omnivision's stock to be artificially inflated, according to the lawsuit.

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Vision Systems Design publishes a nice collection of various companies announcements of Sony stopping CCD production. Among them are Framos video, IDS announcement, and a private email from Vision Components saying that just one CCD model, the B&W 1.4MP, 6.45um pixel ICX285, escaped the axe so far:

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EETimes: TechInsights and eSoftThings analysed power consumption of 3 smart glasses: Google Glass, Vuzix M100, and Optinvent AR Glasses. Imaging functions consume the major power in all three devices:

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Rambus announces its Partners-in-Open-Development (POD) program in collaboration with design firms frog and IXDS to promote the adoption of its lensless smart sensor (LSS) technology.

"Our Partners-in-Open-Development provides a great opportunity for innovators to develop technology for a smarter world. With this program, we encourage developers across the globe to join in to create new products that introduce real-world IoT applications that will touch so many parts of our lives. This is the first step toward expanding the accessibility of an ecosystem that will foster a new generation of innovation," said Gary Bronner, VP of Rambus Labs.

"Our work with lensless smart sensors through the POD program is helping to pave the way for innovations that are sure to inspire and become ubiquitous throughout our lives," said Andrew Zimmerman, president of frog. "The opportunity to partner with Rambus, through our R&D platform frogLabs and other organizations, to build out the burgeoning sensor ecosystem means we are helping to propel solutions that can be adopted much more quickly."

"Opening its innovative lensless smart technology to the developer community enables Rambus to promote what promises to be a robust, intelligent ecosystem around this new approach to sensing and imaging," said Dr. Reto Wettach, founder and design director with IXDS. "We are proud to be among the inaugural POD partners and look forward to being among the first contributors to identify and expand upon existing IoT-based applications for this technology."

Tom's Hardware publishes a nice article accompanied by a Youtube interview with Patrick Gill on the new developments:

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Business Wire: Forza Silicon announces that researchers at NHK presented the design architecture and specifications of the 133MP 60fps CMOS image sensor at ISSCC 2015. The image sensor presented by NHK was designed by Forza Silicon and fabricated using a 0.18 µm 3.3V/1.8V process with 1D stitching.

To date conventional image sensors for 8K applications have used 8 MP and 33 MP solutions in large optical formats. In order to eliminate the bulky lens/color-prism optical system of previous generation cameras, the team developed a single-chip 133 MP image sensor. The sensor takes advantage of Forza Silicon’s Gen 3 readout architecture to achieve frame frequency of 60 fps. The Gen 3 readout architecture uses a pseudo-column parallel design with 14b redundant successive approximation register ADCs to achieve a throughput of 128 Gb/s at full resolution and frame rate.

“Our continued partnership with Forza Silicon through the years to support NHK has resulted in the success of a number of significant projects such as the development of the 133 MP sensor, and previously the 33 MP Super Hi-Vision image sensor. Forza’s dedicated support and its image sensor design expertise enabled us to achieve the Super Hi-Vision 8K single-chip camera — the largest pixel count of any video image sensor,” said Dr. Hiroshi Shimamoto, senior research engineer at NHK Science & Technology Research Laboratories (STRL).

“The advanced research and development initiatives by NHK continue to push the boundaries for UHDTV broadcast experiences. NHK’s next-generation digital broadcast systems stem from their long heritage as the world’s premier R&D center for broadcast camera technology. The groundbreaking technologies we’ve jointly developed have evolved over a span of 10 years as a result of our tight collaboration, and Forza’s decades of design experience and wide selection of silicon-proven IP,” said Barmak Mansoorian, president & co-founder at Forza Silicon.

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Business Wire: Keeping up with its production schedule in the early product announcement, Toshiba starts mass production of the T4KA7, a 20MP, 1/2.4-inch CMOS sensor based on 1.12um BSI pixels. The sensor makes possible the realization of 20MP mobile camera modules with a height of 6mm or less.

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Smithers Image Sensors Auto conference to be held on June 23-25 in Brussels, Belgium announces a list of confirmed speakers including:

• Henrik Lind
  Technical Expert
  Volvo Car Corporation
• Martin Edney
  Lead Systems Engineer Rear & Surround Cameras Advanced Driver Assistance Systems
  Jaguar Land Rover
• Kevin Lu
  Global Manager - Optical Engineering, Product Architect - Image Vision Systems
  Magna Electronics
• Salah Hadi
  Global R&D Director Vision & Night Vision Systems
  Autoliv
• Riccardo Mariani
  CTO
  Yogitech
• Benjamin Stauss
  R&D Engineer – Optical Camera Testing
  TriOptics

Also, Image Sensors publishes an interview with Markus Rossi, Chief Innovation Officer, Heptagon on the company's 3D imaging solutions. Few quotes:

"Optimizing image sensors for 3D imaging is an opportunity, since those system typically have different optical requirement and layout. A key aspect of Heptagon’s products their small mechanical form factor. A novel, wafer-based camera assembly technology - called “FCP” - reduces the mechanical complexity of the camera and projection modules and therefore enables high turn-over, passive alignment manufacturing methods."

"One example for a very important component in depth sensing is the so-called IR illuminator. Our miniature illumination systems are optimised for uniform illumination in ToF applications, pattern generators for contrast enhancement in active stereo as well as structured light systems. Each of this systems needs to be tuned for best optical performance (efficiency, contrast, …) and smallest form factor (need to fit into mobile devices)."

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