Proceedings Article | 5 March 2021
KEYWORDS: Holography, Laser stabilization, High power lasers, Holographic optical elements, Virtual reality, Optical design, Light sources, Laser optics, Laser development, Laser applications
Laser-based holographic techniques continue to grow into commercial markets, used in the production of holographic optical elements (HOEs), for image projection in virtual reality (VR) and augmented reality (AR) devices as well as in white-light analog holography for the generation of ultra-realistic full-color replicas of three-dimensional objects such as museum artefacts. These rapidly developing holographic techniques and holography-based technologies require reliable light sources at multiple wavelengths simultaneously, often in the same optical path. The individual laser performance requirements for holography applications are met by commercially available, extremely reliable, single-frequency or single-longitudinal-mode (SLM) lasers in the visible spectrum with long coherence length, excellent wavelength stability and accuracy, and high, stable output powers. However, the optical alignment and beam combining necessary in multi-wavelength systems can be technically challenging and time consuming. Elaborate assembly and constant maintenance can divert valuable resources away from the more fundamental work necessary to improve quality of the holograms and HOEs. The aim is to develop a laser combiner that provides the necessary performance per laser line with robust beam alignment stability during exposure, and repeatability between exposures, which requires strict control of opto-mechanical component design and thermal management. The performance of a laser combiner, which integrates up to four laser lines with up to 1.5 W of optical power per laser, collinearly aligned with high precision position overlap, angular overlap, and beam pointing stability, and repeatability over long periods of time, is evaluated in this paper. This laser combiner includes the laser sources, control electronics, and beam combining optics and is designed to be easily transportable, providing the ideal combined laser solution to facilitate advancements of holographic techniques.
