Optical assembly for second and third harmonic generation

Abstract

An optical assembly for generating the second and third harmonic frequencies of a laser beam using two optically nonlinear crystals (C1 and C2) arranged in a temperature-controlled environment. The first optically nonlinear crystal (C1) converts the fundamental frequency into the second harmonic, while the second optically nonlinear crystal (C2) converts the fundamental and second harmonic into the third harmonic frequency. The system includes beam-intensity attenuation mechanisms using a first half-wave plate (HWP1) and first and second polarizers (P1, P2), which direct the beam according to the user’s requirements. Motorized linear translation stages (T1, T2) ensure switching between harmonic-generation modes. Different crystal cuts of the optically nonlinear crystals (C1 and C2) enable optimization of phase matching and conversion efficiency. This assembly is designed for highly precise and flexible generation of harmonic laser beams with broad industrial applicability, particularly in laser micromachining.

Images