Total internal reflection coupling module for generating zero-order-free holographic optical fields

The liquid crystal spatial light modulator (LC-SLM) is a widely utilized device for optical field modulation. However, it is commonly plagued by the significant zero-order beam in the output diffraction pattern. To address this limitation, we propose a compact LC-SLM coupling module based on the principle of total internal reflection, which effectively eliminates the zero-order beam while preserving high energy efficiency. When incorporated into a holographic display system, the module markedly improves the image quality. When integrated into a holographic optical tweezer system, the module facilitates the generation of a zero-order-free polygonal vortex conveyor, enabling precise manipulation of individual particles and particle ensembles. The experimental results demonstrate the superior performance of the proposed LC-SLM coupling module, providing a robust and versatile platform for applications in holographic optical tweezers, microscopic imaging, and holographic projection.