Optical implementation of phase extraction pattern recognition

Three-dimensional pattern recognition with a single two-dimensional synthetic reference function

“…In the experiment we used a similar technique employed before in Ref. 9. The Fourier holograms of the input objects are multiplied by a filter function in the Fourier plane, and another Fourier transform ͑FT͒ of this product yields the desired correlation results.…”

Application of serial- and parallel-projection methods to correlation-filter design

“…21 This was possible because of the flexibility of the method. The optical implementations of the various PEC's and other non-LC's 11,[18][19][20]22 and LC's 21 were given elsewhere and are not repeated here, for brevity.…”

“…As an example we demonstrate the efficiency of a new concept in rotation-invariant signal processing by combining the PEC 11,22 and its generalization, the GPEC, with the rotation invariance of the CHC POF. 2 A schematic diagram of the rotationally invariant PEC is shown in Fig.…”

Interferometric electro-optical signal processors with partially coherent illumination

“…If the illumination is spatially incoherent we also take '(r -r') = 8(r -r'), and Eq. (8) reduces to (18) where G(f,) is the FT of g(r)1 2 , fi and f2 are the focal lengths of lenses L, and L 2 , respectively, f, = 2u/Af 2 , and Ia = Ig(r) 12dr. (19) Ia(f,) is the intensity distribution as recorded by a camera and is manipulated as follows: The first term of Ia(f,) (a dc term) is subtracted from Ia(f,) to improve the efficiency.…”

“…18 for coherent illumination. A phase-only holographic filter' 9 to recognize a positive object function, f(r) 2, in a pattern recognition system is recorded in the FL as follows:…”