Abstract:
PixelEXX is developing the world’s smallest camera. Using our patented semiconductor technology, we can implement pixels of hundreds of nanometers, creating miniaturized high-resolution cameras. While our competitors are limited by the smallest industry standards (~1micron), and require heavy process and design innovations to overcome limitations of pixel performance, our low-noise, 250 nanometer pixels deliver three orders of magnitude greater responsivity than traditional 1-5 micron pixel architectures, allowing us to dramatically shrink the size of the camera without sacrificing image quality.
The competitive advantage of PixelEXX cameras ultimately derives from the performance of the PixelEXX optical sensor. Traditional sensors have decreased capacity to store charge as their area decreases. This decreases the upper threshold of CMOS/CCD pixels' intensity limit. In contrast, the PixelEXX sensor does not experience the same reduction of maximum intensity threshold with decreasing size. The PixelEXX sensor also benefits from improved noise characteristics at small size.
Traditionally camera designs benefit by employing the maximum sensor-pixel size while still resolving the circle of confusion determined by the camera optics (typically 2 or 3 pixels across the circle of confusion). Reducing tradition pixel size below this number substantially degrades performance because these pixels’ maximum threshold scales with area and their noise properties degrade with decreasing area. For example, with 10 pixels per circle of confusion the maximum light intensity measurable per resolvable spot is unchanged (each pixel can measure 1/10 the light, but the same light is spread over 10 pixels); however, the noise per pixel is now substantially increased resulting in a highly degraded image. Contrast this to the camera design considerations using a PixelEXX sensor. Increasing the number of pixels per circle of confusion does not substantially effect the maximum light threshold per pixel, nor does it effect each pixels intrinsic noise level. Considering PixelEXX sensors in the example, 10 smaller pixels instead of 1 larger pixel per circle of confusion increases the maximum measurable intensity by a factor of 10 without increasing the noise contributed to the image. This enables currently unachievable image contrast in a compact camera, providing a competitive advantage by delivering a crucial product benefit unavailable to other technologies or providers.
Finally, having a novel semiconductor structure that enables submicron pixels presents an opportunity to position PixelEXX to lead the next era of imaging. This next era will focus on functionality. With extra pixels, numerous opportunities will be opened up for advanced imaging. The sensor’s small size and fast response times (theory predicts femtosecond response) offer unique opportunities for spatial and temporal oversampling. The resulting large numbers of pixels can be employed in a compact multiaperture arrangement to deliver significantly enhanced color mapping over traditional semiconductor imaging arrays (under normal light conditions), multispectral imaging (under low light conditions), 3-dimensional image reconstruction, motion free auto-focusing, or a combination of the above.
PixelEXX’s first application is centered on medical endoscopy because crucial medical procedures
demand smaller, smarter visualization tools. The company’s accomplished team is working to provide a unique and valuable suite of imaging tools.