Research on High Power Laser Damage Resistant Optically Addressable Spatial Light Modulator

Abstract

Liquid crystal spatial light modulators (LC-SLMs) are devices that can accurately adjust the parameters of beam amplitude, phase, wavefront and polarization. However, due to the limitation of laser damage resistance of component materials, LC-SLMs still have difficulty meeting the application and development needs of a high-average power laser system. Here, we proposed an optically addressable spatial light modulator (OASLM) based on a sapphire substrate. Due to the good thermal conductivity of sapphire, the laser damage resistance of the device was greatly improved. The thermal distribution of OASLM based on the sapphire substrate and the K9 substrate is analyzed by a laser-induced temperature rise model. The experimental results also show the excellent performance of sapphire OASLM under high-power CW laser irradiation, its laser power density is increased from 10 W/cm2 to 75 W/cm2, and the working time is more than 30 min. By bonding sapphire to the other side, the laser power density can be increased to 100 W/cm2, and these are completed without active heat dissipation. This method provides a feasible path for high-average-power SLMs.

Keywords

• laser damage resistance
• optically addressable
• spatial light modulators
• sapphire substrate