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We propose a simple real-time system and demonstrate its use for measuring dynamic optical phase perturbation. In this system we used a 0.1-wt. % Fe:LiNbO(3) to record the self-interference grating with incident light. The system is a new kind of real-time holographic interferometer. After rise time in the interferometer, the speed for showing the fringes is as fast as that of dynamic phase perturbations. Characteristics of the interferometer are proposed and examined.

A novel signal processing scheme for detecting distance and velocity signals simultaneously is demonstrated. In this method, a frequency-modulated diode laser is used to illuminate a dual-channel Michelson interferometer with two orthogonal output signals. The distance and the velocity signals then exist on the beat frequencies of the output interferometric signal. Two interferometric output signals with a quadrature phase shift are used to adjust the gating time period of frequency counters for beat-frequency measurement. The distance and velocity signals can thus be obtained from the counting number within the gated-in time period.

A different setup of the Mach-Zehnder interferometer for testing the convergent wave front is described. A Shack cube is used to replace a traditional recollimator and a parallel-plate beam splitter. An equivalent pupil model has been suggested that describes the point diffraction mechanism. The calibration procedures for the Mach-Zehnder interferometer are described. The Shack-cube beam splitter has the advantages of compactness and better reference-beam quality compared with the recollimator and the parallel-plate beam splitter.

A shearing interferometer with a Kitty-type self-pumped phase-conjugate mirror is developed. The measurement of the focal length of a lens is demonstrated with a standard deviation of 1.5%. In addition, we measured the microdisplacement in the range of tens of micrometers with an error less than 2% by using the interferometer.

A deep phase-modulation signal with a sinusoidal waveform is employed on a Michelson interferometer for detecting distance and velocity signals simultaneously. This approach is simple to implement and has a wide-dynamic-range capability with a linear scale factor.

A scheme for distance and velocity signal detection is implemented. This technique is based on a laser diode with its frequency modulated by a triangular waveform and followed by time gating.

We propose a matrix-matrix multiplication by using anisotropic self-diffraction in BaTiO(3). The input matrices are carried by the two incident beams with special Bragg-matched incident angles. The output matrices are produced by anisotropic self-diffraction with the polarization orthogonal to those of the incident matrices. By thresholding the output this architecture is particularly suitable for the applications of optical interconnects and an optical switch.

We present a simplified method, based on experimental observations, for predicting the best incident conditions for obtaining the highest reflectivity of a Cat-type self-pumped phase conjugator with given crystal dimensions.

Experimental results of phase-only circular harmonic filtering implemented in a standard Fourier transform correlator are presented. The filter is a computer generated hologram which contains only the phase information of a single circular harmonic component of the target. The result with simple binary objects bears out the simulation result published earlier [H. F. Yau and C. C. Chang, Appl. Opt. 28, 2070-2074 (1989)] in that the filter is indeed shift- and rotational-invariant and that the correlation peak is more prominent than that produced by ordinary circular harmonic filtering.