Following the CMOS Track

Abstract

Photonfocus was founded in 2001 to bring CMOS sensors and CMOS cameras to the machine vision market. The LinLog CMOS sensor technology and the associated digital camera platform were developed at CSEM SA. After focusing on the automotive market, refocusing on the machine vision market led to stable growth of the company since 2012. Photonfocus has a worldwide sales network and supplies a wide range of standard cameras and OEM products to the machine vision and optical metrology market. Custom CMOS camera design is one of Photonfocus' strength. www.photonfocus.com CompanyIn the late nineties of the last century, it was foreseeable that CMOS image sensor technology would have a very strong and fast evolution due to the shrinking of the CMOS structures and developments in the fields of semiconductor research, microtechnology, nanotechnology and photonics. Early pioneering work already showed that techniques and ideas of CCD image sensors could be transferred to CMOS sensor technology. The rapid growth of digital photography and the smart phone market has sped up the transition process in the last few years.The basis for founding Photonfocus in 2001 was the CMOS sensor development under the umbrella of the Centre Suisse d'Electronique et Microtechnique CSEM in Switzerland. After designing small imagers and smart CMOS sensors, the accumulated knowledge also enabled the design of a high speed megapixel CMOS sensor for machine vision applications, optical metrology, and, in a more general sense, of twodimensional image scenes. In addition to sensor development, the compatibility of CMOS sensors with the CMOS FPGA (field programmable gate arrays) technology was exploited to develop and realize software defined camera platforms. Due to the high flexibility of FPGAs, advanced control mechanisms for the CMOS image sensors can be implemented. For example, it is possible to change the complete feature set of a CMOS imager from frame to frame. Thus, FPGAs can be used to realize extraordinary readout schemes that allow fast readout of the most relevant data subsets. The latter possibility, together with multi-tap readout architectures of the sensors, is the basis for high speed imaging systems. In addition, image processing in FPGAs adds to the high flexibility of CMOS image sensors, resulting in a powerful combination and enabling a wide range of applications in machine vision and optical metrology. To ease interfacing with image processing systems, the interfaces of software-defined cameras rely on approved industrial interface standards. Photonfocus CMOS sensorsPhotonfocus has developed CMOS image sensors with 1.0, 1.4, and 4.3 megapixel resolution. The full well capacity of these sensors ranges between 90 to 200 ke -, which results in high signal-to-noise ratios (SNR), being especially useful in optical metrology. The absence of smear and blooming provides