Zero-order-free complex beam shaping. (August 2022)

• Record Type: Journal Article
• Authors: Liang, Yansheng; Yun, Xue; He, Minru; Wang, Zhaojun; Wang, Shaowei; Lei, Ming
• Is Part Of: Optics and lasers in engineering. Volume 155(2022)
• Publication Date: 2022-08
• Subjects: Beam shaping -- Spatial light modulator -- Zero-order -- Novel beams; SLM Spatial light modulator -- TC Topolotical charge -- CGH Computer-generated hologram; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2022.107048
• Languages: English
• ISSNs: 0143-8166

Abstract

Highlights: A digital lens and an asymmetric triangle reflector are employed. Complex beams are created without the burden of the zero-order. New complex-amplitude coding algorithms are proposed by introducing the digital lens. Zero-order-free beam shaping is of interest to the optical trapping and microscopy community. Zero-order-free beam shaping can be applied to high-power applications. Abstract: The unwanted zero-order diffraction is still an issue in beam shaping using pixelated spatial light modulators. In this paper, we report a new approach for zero-order free beam shaping by designing an asymmetric triangle reflector and introducing a digital blazed grating and a digital lens to the phase hologram addressed onto the spatial light modulator. By adding the digital lens phase to the previously reported complex-amplitude coding algorithms, we realized the generation of complex beams without the burden of zero-order diffraction. We comparatively investigated the produced complex light fields using a modified complex-amplitude coding algorithm to validate the proposed method.