Optical processor design is the art of architecting a computing machine with components that are either currently available or which can be developed with a reasonable extension of current technology. There is no difference between this and the design of a processor using any other technology except that in optics the component selection is more limited and the cost of implementing certain classes of operations is far less. This paper outlines the characteristics of many current components and the impact of these characteristics on optical architectures. At the present time the most critical components in optical processing are at the interface with other processing technologies. These critical components are spatial light modulators and photosensors. Advances in semiconductor technology and opto-electronics for optical communications may greatly reduce the current component limitations. In this paper suggestions are provided for new component development and the impact of such developments on optical processing technology is discussed.