Optical processing: a near real-time coherent system using two Itek prom devices

Abstract

A near real-time coherent optical processing system has been demonstrated using two Itek PROM devices and a TV monitor. One PROM acts as an incoherent-to-coherent image converter and the other as a laser addressed, programmable Fourier plane filter. The TV monitor provides an on-line display of the filtering process.

Analog Photonics Computing for Information Processing, Inference, and Optimization

“…Early SLMs were based on the Pockels effect with few prospective devices. [32][33][34] Liquid crystal technology is the most commonly used technology for SLMs today. Another significant step was the invention of the first optical transistor, [35] the hope for small integrated circuits.…”

“…The most common parameter estimation technique is called the least-squares estimation. Here, the optimum parameter is defined through the minimization of the sum of the mean squared loss min (33) which can be connected with the conventional QP. The optimal solution can be obtained by differentiating Equation (33) and equating it to zero with respect to parameters 𝛽 j .…”

“…Here, the optimum parameter is defined through the minimization of the sum of the mean squared loss min (33) which can be connected with the conventional QP. The optimal solution can be obtained by differentiating Equation (33) and equating it to zero with respect to parameters 𝛽 j . In matrix notation, the solution can be written as…”

“…There exist different modifications of the proposed procedure: generalized least squares, where one introduces a certain degree of correlation between the residuals 𝜖 i (33), or the weighted least squares, where the knowledge of the variance of observations is incorporated as the coefficients w k before each of the residual. Moreover, intrinsically different techniques can be based on maximum likelihood estimation, Bayesian methods, or regularization.…”

A short history of optical computing: rise, decline, and evolution

“…Some of the early SLMs were based on the Pockels effect and two devices were very promising: the Phototitus optical converter with a DKDP crystal was used for large screen color display and also for optical pattern recognition, but the crystal had to work at the Curie point (-50°C) 36,37 ; the Pockels Readout Optical Modulator (PROM) was used for optical processing 38,39 , but it was limited as it required blue light for writing and red light for readout.…”