Optimization of the Liquid Crystal on Silicon Technology for Laser Microprocessing Applications

Phase-only spatial light modulators (SLMs) allow to bring adaptive optics and diffractive optics methods into laser material processing. We focus our research on the liquid crystal on Silicon (LCOS) technology, which is known from display and photonic applications for its high resolution, flexibility, technological and economical feasibility. The broad range of applications in laser material processing imposes various requirements on such dynamic components. Most important is the ability of the SLM to withstand the higher intensities and energies over the long time. This requires better understanding of the laser induced damage threshold (LIDT) levels of these devices on system and component level as well as long term performance degradation, especially if ultra-short pulse (USP) light sources are used. The measures to improve LIDT and other important parameters while keeping the economically feasible wafer-scale fabrication of LCOS SLMs will be discussed.