ULTRASONIC LASER MODULATION TECHNIQUES.

Integral equations describing the slope and trajectories of light rays traversing various periodic refractive index variations are developed. The complexity of the equations led to the use of analog computer techniques for solving three differential ray-trace equations for the slope and trajectories of the light rays. The use of the slope solutions for designing a Fabry-Perot laser interferometer configuration for pulse shaping the output of laser oscillators is described. Experiments are described which demonstrate the feasibility of internally gating the output of a Nd3 doped glass laser by coupling focused acoustic energy from a cylindrical transducer to a laser rod through a liquid medium. This liquid coupling technique has eliminated most of the bonding problems arising from the flash lamp and stray laser radiation damage encountered with the previously reported technique of bonding the transducers directly onto the laser rod. Preliminary experiments are reported which demonstrate that no appreciable increase in the deflection of a light beam by acoustic waves can be obtained by maintaining the acoustic medium near a phase transition region. Author