HoloTile RGB: Ultra-fast single-shot, discretized, full-color computer-generated phase-only holography

Abstract

We demonstrate the first use of the HoloTile Computer-Generated Holography (CGH) modality on multi-wavelength targets. Taking advantage of the sub-hologram tiling and Point Spread Function (PSF) shaping of HoloTile allows for reconstruction of high-fidelity, pseudo-digital multi-wavelength images, with well-defined discrete output pixels, without the need for temporal averaging. For each wavelength, the target channels are scaled appropriately, using the same output pixel size. We employ a stochastic gradient descent (SGD) hologram generation algorithm for each wavelength, and display them sequentially on a HoloEye GAEA 2.1 Spatial Light Modulator (SLM) in Color Field Sequential (CFS) phase modulation mode. As such, we get full 8-bit phase modulation at 60 Hz for each wavelength. The reconstructions are projected onto a camera sensor where each RGB image is captured in a single shot. While these show impressive color reconstructions, the method can be adapted to any wavelength combination for use in a plethora of multi-wavelength application.