Input-output characteristics for imaged transducers

An image processor used as a position transducer is treated on an input-output basis. If processing speed is sufficiently fast the input-output characteristic is independent of frequency and can be represented as a gain function. The input is a function of the image pattern (including intensity if grey level is used) and the output is used for control or other purposes but control is the issue considered here. A Fourier phase in conjunction with projection concepts is used to obtain control signals in the image processing. A solution to two-dimensional rotation of the object input pattern is presented. The technique can easily be extended to deal with dilation problem. Results that are important to closed loop design are included.