Regenerative optical amplifier

Abstract

The invention offers a regenerative optical amplifier enabling voltage to be easily applied to polarizing elements such as Pockels cells, without the need for complicated drive circuitry. An input beam of S-polarized light is reflected by a polarizerand advances to a Pockels cell. In the time it takes for the input beam, having once passed through the Pockels cell, to be reflected by a reflective mirrorand return to the Pockels cell, a voltage Vcausing a 90-degree rotation in the polarization of transmitted light is applied to the Pockels cell, and this applied voltage Vis maintained. The input beam is converted by the Pockels cellinto a P-polarized light pulse which is transmitted by the polarizer. Subsequently, the light pulse is converted from P-polarized light to S-polarized light and back to P-polarized light with each roundtrip of the Pockels cell, while passing each time between the reflective mirror, laser crystaland reflective mirror, so as to be amplified in the resonator formed thereby. The amplified light pulse is extracted by applying a voltage Vcausing a 90-degree rotation of the polarization of the transmitted light to the Pockels cellto convert the light pulse to S-polarized light which is then reflected out of the resonator by the polarizer