X. J. Lu

Real-time optical scanning correlator

A real-time large-capacity rapid-scanning optical correlator utilizing a rotating grating concept is described. We have shown that the proposed optical scanning correlator (OSC) is capable of processing large-capacity optical memories with rapid spectrum scanning. With the implementation of a closed-circuit TV system, the OSC system can be applied in real-world situations. We have also experimentally tested the overall correlation sensitivity of the OSC system due to spectrum scanning, object orientation, scale changes, and tilting of the rotating grating. Several experimental results obtained with this proposed OSC system are included.

Implementation of Boolean logic gates using a microchannel spatial light modulator with liquid-crystal televisions

A programmable optical system that can perform binary Boolean logic operations with a microchannel spatial light modulator (MSLM) is presented. The MSLM is used as an adder, an inverter, a subtractor, or a buffer. We used three liquid-crystal televisions with a computer as input interfacing devices. Through the use of its feedback loop, the system can consecutively execute a series of logic operations. Experimental results are provided.

Real-time programmable image subtractor using a magnetooptic device

In an effort to combine the advantages of optical information processing and the flexibility of digital computers, a real-time image subtraction system has been developed. A microcomputer is employed to control a Litton magnetooptic device (MOD) and also to interface the MOD to a video camera. The performance of the system in image subtraction is discussed in detail. An experimental demonstration of image subtraction is shown.

Large-capacity real-time spatial–spectral scanning optical correlator

A large-capacity real-time spatial-spectral scanning optical correlator utilizing the concept of a rotating multicolor grating is described. It was experimentally observed that implementation of a closed-circuit TV system gives the correlator a real-world application. The color sensitivity of the correlator is also demonstrated. The experimental results using single and double lasers with two primary colors are presented.

Application of a magnetooptic spatial light modulator to white-light optical processing

The application of a programmable magnetooptic spatial light modulator to white-light optical signal processing is presented. We have shown that the magnetooptic device responds to the polarized white light, in which a wide range of color object patterns can be generated. Since the magnetooptic device is a transmitted type spatial light modulator, it is very suitable for real-time programmable spatial filter synthesis and object pattern generation for optical signal processings. Experimental demonstrations of some of the elementary spatial filter syntheses and pseudocolor encodings are provided.

Diffraction by a 3-D oriented grating and its use in scanning correlation detection

The equation of diffraction directions for a3-D oriented grating is derived. By rotating and tilting the grating it is shown that a square array of filters can be generated. This technique has been used in object plane scanning correlation detection and results of a demonstration experiment are also presented.

Operating characteristics and applications of a microchannel spatial light modulator under white-light illumination

A microchannel spatial light modulator-based white-light optical processor is presented. The basic principle of the system performance is studied. The operating characteristics of the spectral and contrast responses are measured. Applications to real-time optical processing operations which include the intensity color encoding analog hard clipping in colors are provided.

White-Light Optical Signal Processing With A Programmable Magneto-Optic Device

The application of a programmable magneto-optic spatial light modulator to white-light optical signal processing is presented. We have shown that the magneto-optic device responds to the polarized white-light, in which a wide range of color object patterns can be generated. Since the magneto-optic device is a transmitted type spatial light modulator, it is very suitable for real-time programmable spatial filter synthesis and object pattern generation for optical signal processings. Experimental demonstrations of some of the elementary spatial filter syntheses and pseudocolor encodings are provided.