RESUMEN
We have constructed and demonstrated a single-pixel implementation of an all-optical membrane-based spatial light modulator as a compact optical wave-front error correction device. High rates of response of as much as 20 kHz in an open-loop configuration were obtained. The device was then used in an adaptive-optics servo to compensate successfully for a 1-kHz sinusoidal phase error with a peak-to-peak excursion of approximately pi/7 rad. A small-signal servo gain of the order of 10 was inferred from the closed-loop measurements.
RESUMEN
We have demonstrated an all-optical diagnostic system that enhances the observation of defects in periodic structures. This real-time technique employs a spatial light modulator as a smart-pixel array for information processing in the Fourier transform plane of a lens. The system also includes a phase-conjugate mirror for autoalignment and for correction of optical wave-front aberrations that are imparted on the object light by the smart-pixel processor and its associated optical train.
RESUMEN
A self-pumped atomic sodium phase-conjugate mirror was modified to include an amplitude modulator, which thus formed a device capable of encoding temporal information onto the phase-conjugate return beam. Modulation rates of as much as 4 MHz with modulation depths in the range of 70-90% (both limited by the electronics and the modulator) have been obtained by using an intracavity acousto-optic modulator.
RESUMEN
An approximate analytical model has been developed which allows the voltage characteristics of the liquid crystal layer of a silicon liquid crystal light valve to be determined once the photocurrent level and device parameters have been specified. This model significantly decreases the computation time compared to current numerical techniques.
RESUMEN
Self-pumped optical phase conjugation has been demonstrated for the first time to our knowledge in a resonant atomic system. This process was implemented by using a single cw pump beam to excite a sodium-vapor oscillator. The counterpropagating optical fields inside this oscillator then combine with the pump beam in an internal fourwave-mixing interaction to yield the phase conjugate of the incident (pump) beam.
RESUMEN
An experimental investigation of laser-oscillator frequency locking by a four-wave interaction was conducted. An experiment was performed that successfully demonstrated the locking of two cw dye lasers using this concept with Na vapor serving as the nonlinear (coupling) medium.