During the past three decades, optical information processing has received a lot of attention from large number of engineers and physicists. Although both optical coherent and incoherent processing can be employed for optical correlation and convolution, and wide variety of information processing functions can be performed, however, several new faster approaches to VLSI implementation of electronic cross correlation or convolution have been demonstrated recently. Due to increasingly importance of correlator in apply to digital image processing, stereo matching, and pattern recognition. In this paper, we perform a comparison between the electronic and optical correlator in terms of several system parameters, such as timing, area and power consumption. Such comparison may assist the system planner in actual implementation