A hybrid character recognition system is described. It is composed to two parts, the feature extractor and the inner- product correlator. Ten Arabic characters from 0 to 9 are tested for their recognition by the system. The experimental results show that all the printing characters are perfectly recognized with rotational invariance of 15 degree(s) angle, and the recognized ratio for hand-writing characters is over sixty percent.
"Hybrid optical correlator for character recognition", Proc. SPIE 2238, Hybrid Image and Signal Processing IV, (1 June 1994); doi: 10.1117/12.177728; https://doi.org/10.1117/12.177728