Electro-optical processor for measuring displacement employing the Talbot and the nonsteady-state photo-electromotive force effects.

We present a device for measuring displacement based on the Talbot and the nonsteady photo-electromotive force effects. The proposed device does not require any numerical signal processing since its output signal is, in appropriate regions, linearly related to the measured displacement. The proposed system requires an illuminating field with a sinusoidal amplitude distribution and low fringe visibility.

Grating cavity dual wavelength dye laser.

We report simultaneous dual wavelength dye laser emission using Littman-Metcalf and Littrow cavity configurations with minimum cavity elements. Dual wavelength operation is obtained by laser operation in two optical paths inside the cavity, one of which uses reflection in the circulating dye cell. Styryl 14 laser dye operating in the 910 nm to 960 nm was used in a 15%:85% PC/EG solvent green pumped with a Q-switched doubled Nd3+:YAG laser.

Rubidium vapor holography for noncontact adaptive detection of ultrasound.

We describe an adaptive interferometer based on rubidium vapor, which combines a good signal-to-noise ratio with a high cutoff frequency of approximately 1 MHz. These features can be useful for optical detection of ultrasound generated in diffusely scattering objects in the presence of strong environmentally produced vibrations.

Adaptive photodetector for assisted Talbot effect.

We use an adaptive photodetector for measuring the visibility of the Fresnel diffraction patterns generated by a grating. Visibility is measured in real time, with high spatial resolution, and without any signal processing. This method is well suited for analyzing the Talbot effect and its many applications.