Resolution-preserving passive 2D/3D convertible display based on holographic optical elements

Abstract

We propose and demonstrate a resolution-preserving passive 2D/3D convertible display by two individual wavelengths. It uses a holographic optical element to generate two images and passively separate the exit pupils for these two wavelengths, which forms two viewpoints for each of the observer’s eyes. Due to Bragg-mismatched reconstruction of two similar but distinct wavelengths, the images are separated in space. They can be fused into one through the convergence function of human eyes. By switching the input image source, the conversion between 2D and 3D mode can be realized. This method is resolution-preserving and 2D/3D convertible with no extra active components. For experimental verification, a proof-of-concept projection-type prototype is assessed.

Hybrid Approach of Holography and Augmented-Reality Reconstruction Optimizations for Hyper-Reality Metaverse Video Applications

“…The fabricated HOE sample, as shown in Fig. 11(d), is a volume Bragg grating that was holographically recorded in a reflective-type using a layer of photopolymer (model: Bayfol HX200, Covestro), a photosensitive material with a thickness of 240 μm [52], [53]. A 170 μm thick glass substrate was laminated with the photopolymer film.…”

“…This phenomenon occurs because the HOE fabricated in this study is a reflective-type volume Bragg grating produced by monochromatic light (recording light wavelength: 532 nm), and diffraction in blue or red light is different from that in green light (recording wavelength). The diffraction angle θ reflected at the lattice planes of the volume Bragg grating (lattice plane period: p) depends on the wavelength (λ) according to the equation sinθ = λ/2p [50], [53]. Therefore, when white light is incident on the volume hologram sample, the degree of matching of the red and blue colors is inadequate, with the green color being centered.…”