Abstract

Laser guide stars (LGS) are required to obtain complete sky coverage for astronomical telescopes incorporating adaptive optics. Resonant scattering of a high power pulsed laser from atomic sodium in the mesosphere is the most promising technique for the production of a LGS. However, due to saturation of the sodium layer, the efficient generation of a bright LGS using pulsed excitation is difficult. We are devising a modular system where the brightness of the LGS can be increased linearly by adding more laser units [1]. A frequency-locked cw dye laser acts as a master oscillator (MO) which is alternately pulsed amplified through an array of dye amplifiers by means of time-multiplexing thus creating a pulse-train. Consequently, the peak power of each pulse does not increase when the average power is scaled to give a larger photon return from the LGS.

© 1996 IEEE