Apparatus for stabilizing second harmonic pulse output in a laser system operating by pulses

摘要

The present invention relates to an apparatus for stabilizing second harmonic wave pulse output in a laser system operating by pulses. The apparatus of the present invention comprises: a pulse laser oscillating unit (110) which outputs a laser pulse; a nonlinear crystal (120) which converts the laser pulse of a first wavelength output by the pulse laser oscillation unit (110) into a second harmonic wave with a value that is half of the first wavelength, and outputs the converted second harmonic wave; and an optical absorption filter (130) which absorbs a portion of the energy of the converted second harmonic laser pulse from the nonlinear crystal (120) to output the second harmonic wave with a lower energy. The thus-configured apparatus of the present invention supplies a fundamental wave in a stable state and having a small PTP value and high level energy to the nonlinear crystal, in order to obtain the second harmonic wave which is in a more stable state and has a small PTP value and a variety of energies.

主权项

1. An apparatus for stabilizing second harmonic wave pulse output in a laser system operating by pulses, the apparatus comprising:
a pulse laser oscillator for outputting a first laser pulse; non-linear crystals for converting the first laser pulse having a first wavelength into a second laser pulse having a second wavelength being half the first wavelength and outputting the second laser pulse; a light absorption filter for absorbing energy of the second laser pulse and outputting a third laser pulse having an energy lower than the second laser pulse; moving means for moving the light absorption filter away from a laser path and selectively placing the light absorption filter on the laser path; and a control unit for controlling the moving means to adjust the energy of the second laser pulse according to a selected energy mode, wherein the control unit comprises:
an energy mode selection unit for receiving the energy of the second laser pulse;at least one position sensor for outputting position signals of the light absorption filter;a controller for generating control signals to control the moving means based on the position signals and the energy of the second laser pulse wave received from the energy mode selection unit.