From electronic photography to seeing chips-the future of image sensing

Thanks to the advances of semiconductor technology, solid state image sensors with impressive properties can be realized today: CCDs with 26 million pixels are commercially available. Pixel size has been reduced to 5×5 μm² and less. This enables one to integrate electronic circuitry with each pixel, providing added functionality for custom photo-ASICs and smart image sensors: single-chip cameras with on-chip analog-to-digital converters for less than $20 are advertised; image sensors have been developed including novel functionality such as real-time selectable pixel size and shape, the capability of performing arbitrary convolutions simultaneously with the exposure, as well as variable, programmable sensitivity of the pixels leading to image sensors with a dynamic range exceeding 100 dB. It is concluded that the possibilities offered with custom smart image sensors will influence the design and the performance of future imaging systems in many disciplines, reaching from optical metrology to machine vision on the factory floor and in robotics applications