A real-time incoherent optical image correlator which employs a laser diode, an AM-FM AOD, and a TDI mode CCD is described. A theoretical analysis is given to indicate that this system possesses high resolution capability by virtue of its special image feeding approach using an AOD in an AM-FM mode. Experimental results showing the system impulse response are presented to confirm the theoretical analysis. Correlation functions of some example images and the scale invariant performance of this incoherent optical correlator by adopting an adaptive AM-FM signal format are demonstrated.
"A Real-Time Optical Correlator Using An AM-FM Acousto-Optic Device", Proc. SPIE 0564, Real-Time Signal Processing VIII, (4 January 1986); doi: 10.1117/12.949721; https://doi.org/10.1117/12.949721