A holographic technique by which two dissimilar optical fields can be subtracted to yield only their difference is presented. The principle underlying this technique is that of optical interference between a holographically reconstructed field and a direct real-time one. Experimental verification is presented for the three cases of image-plane, fourier-transform, and Fresnel side-band holograms. Also considered is the application of this concept to change detection between photographic transparencies of some scene taken at different times.
K. Bromley, M. A. Monahan, J. F. Bryant, and B. J. Thompson, "Holographic Subtraction," Appl. Opt. 10, 174-181 (1971)