Daniel Van Blerkom from Forza Silicon discusses sensor design trends and digital camera technology

Smithers Apex interviews Daniel Van Blerkom in the lead up to his presentation at Image Sensors Americas 2014

Q. Please briefly describe your background in digital imaging.

I've been involved in opto-electronics since graduate school, initially in the design of high-speed optical links. But as some of you can probably relate, once you've been infected by the beauty (and frustration!) of imaging, it's a hard addiction to shake. When Micron Technology acquired Photobit Corporation in pursuit of high-volume, low-cost applications, the demand for sophisticated applications was growing quickly, which led to the formation of Forza Silicon Corporation in 2001 and my position as Co-Founder & Chief Technology Officer.

Q. How do the consumer and professional applications merge, and what does this mean for developers of digital camera technology?

It's an exciting time to be working in imaging and camera technology. The field has become so dynamic with rapidly increasing performance constantly coming on the market. New approaches to imaging, like lightfield cameras and novel detector materials, are also breaking the field open. Comfortable business models don't last long before they are confronted from both ends of the spectrum: 1) higher-end devices becoming more affordable and 2) lower-end devices improving in performance and features. Witness the trend in cinematography with DSLR cameras. Similarly, advanced video resolution levels are now available to more than just professionals.

The makers of professional equipment are able to address certain technicalities that become difficult at the consumer market level, and this creates pressure on the imaging technology as we move forward. For example, camera testing and calibration can't be nearly as thorough in a consumer product as in a professional one. Also, cost limitations remove some of the flexibility for image processing to correct sensor offsets.

The cost constraints on the optical systems of consumer equipment create a more challenging situation for the sensor, requiring the pixels to capture light with larger angular variation. Also, the power supplies and power conditioning are generally worse in consumer products compared to professional products, requiring more on-chip conditioning of the supplies and references. Finally, consumer products typically push more circuitry into the sensor to reduce system cost and size, suffering the additional heat generated on the sensor which impacts pixel performance.

Q. At the image sensor level, what trends do you see in design, and what will emerge as the standards of tomorrow?

Backside illuminated technology (BSI) is now becoming standard, even in custom sensors. This, coupled with 3D packaging with dense interconnects, is creating an exciting opportunity in stacked sensors. We are currently working on projects utilizing pixel level interconnects in 3D stacked devices. While there are new design issues and challenges for 3D stacked sensors, the possibility for tight integration of the pixel with the processing logic makes stacked sensors very compelling, for instance, in the rapidly accelerating market of connected smart devices. In addition to other inventive designs, the Forza Silicon team is in the process of developing a compact, low-power 3D sensor technology that can enable a wide range of smart applications in the programmable world (otherwise know as the "Internet of Things").

Q. And finally, we are delighted to have you participating as a speaker, what are you hoping to gain from your attendance at the event?

It's always a great opportunity to learn what others in the imaging industry are pursuing and gain valuable insight into new technology advancements.