Abstract

The Horner efficiencies of the phase-only filter (POF) and the binary phase-only filter (BPOF) used for optical pattern recognition are discussed relative to both the filter formulation algorithm and the geometry of the object. Both the POF and BPOF transmit 100% of the energy incident on the filter. The POF sends 100% of this energy to the correlation, while the BPOF only sends 40%. However, in each case, the shape of the correlation peak is strongly affected by the structure of the object. The correlation narrows, causing the peak value to increase as the number of edges in the object increases. The peak value can reach nearly 100% under optimum conditions. Computer simulations are shown for both filters. Experimental results are obtained by using the BPOF written onto the magneto-optic spatial light modulator.

© 1992 Optical Society of America