In the 1990s, advances in semiconductor technology reduced the barriers between making optical measurements and processing them. Consequently, exploiting this new capability became a topic of focused research. Early performers recognized that the burden of image formation was no longer borne solely by optics. Instead, the goal was to make measurements from which images could be formed or image information extracted. More than three decades later, the planes in which optical measurements are made and processed are so intimate they are nearly inseparable.