Accession Number : ADA291674

Title :   Effects of Spatial Light Modulator Transmissive and Reflective Dead Zones on Optical Correlation.

Descriptive Note : Interim rept.,

Corporate Author : ROME LAB HANSCOM AFB MA

Personal Author(s) : Gianino, Peter D. ; Woods, Charles

PDF Url : ADA291674

Report Date : APR 1992

Pagination or Media Count : 46

Abstract : We present both analytical calculations and computer simulations for optical correlation in correlators using pixellated Spatial Light Modulators (SLM) with transmissive (or reflective) dead zones. The input plane SLM modulates the intensity in its active areas while its dead zones transmit (or reflect) all of the light. ln the filter plane SLM the dead zones are similar,but the active areas modulate both phase and transmittance to produce either a phase-only filter, a binary phase-only filter, or a classical matched filter. When these dead zones appear in the input plane, we add a dc block in the filter plane for noise reduction and use a filter reference image that is smaller than the input SLM size to reduce false correction peaks. We calculate the correlation peak intensity, the signal-to-noise ratio and the energy throughput efficiency as a function of dead zone area in both the input and filter plane SLMs. Analysis shows that the opaque dead zone results are a special case of the transmissive dead zone results. We also calculate peak intensities when one SLM has opaque dead zone and the other, transparent dead zone.

Descriptors :   *OPTICAL CORRELATORS, *LIGHT MODULATORS, COMPUTERIZED SIMULATION, INPUT, SPATIAL DISTRIBUTION, PEAK VALUES, COMPUTATIONS, ENERGY, SIGNAL TO NOISE RATIO, INTENSITY, EFFICIENCY, TRANSPARENCE, OPTICAL IMAGES, REFLECTION, TRANSMITTANCE, CORRELATION, THROUGHPUT, NOISE REDUCTION, PIXELS, MATCHED FILTERS, DIRECT CURRENT, CORRECTIONS, OPACITY.

Subject Categories : Optics
      Electrooptical and Optoelectronic Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE