A coherent optical pattern recognition system using a frequency plane correlator with weighted matched spatial filter synthesis is described. The case study chosen to describe this application of holography is the determination of all pages in a microfilm data base on which a given key word is present.
Joseph E Hinds,
"Optical Word Recognition: Case Study In Coherent Optical Pattern Recognition," Optical Engineering 19(5), 195716 (1 October 1980). https://doi.org/10.1117/12.7972593