상세정보
학술지
Numerical Analysis on a Viewing Angle Enhancement of a Digital Hologram by Attaching a Pixelated Random Phase Mask
- 발행일
- 202102
- 출처
- Applied Optics, v.60 no.4, pp.A54-A61
- ISSN
- 1559-128X
- 출판사
- Optical Society of America (OSA)
- 협약과제
- 19MB1200, 모바일 완전입체 단말 및 콘텐츠 기술 개발, 황치선
- 초록
- In a digital hologram, the maximum viewing angle of a computer-generated hologram (CGH) is limited by pixel pitch due to the diffraction grating equation. Since reducing pixel size of display panel is challenging and costly, we propose a method to expand the viewing angle of a digital hologram by attaching an aligned pixelated random phase mask (PRPM) onto the CGH pattern based on analysis of simulation results. By introducing a phase-averaging process to the widely used iterative Fourier transform algorithm, an optimized CGH pattern can be obtained in conjunction with a PRPM. Based on scalar diffraction theory, viewing angle enhancement characteristics were verified by comparing the perspective views of a two-plane hologram using a virtual eye model. In addition, we performed full electromagnetic simulations that included effects due to potential fabrication errors such as misalignment, thickness variation, and internal reflections and diffractions between the CGH and random mask patterns. From the simulation results, by attaching a 1.85 쨉m-sized pixel pitch PRPM to a 3.7 쨉m CGH, the viewing angle can be easily expanded almost identical to that of a CGH with 1.85 쨉m-pixel pitch.
- KSP 제안 키워드
- Computer generated holograms(CGH), Diffraction grating, Digital hologram, Display Panel, Eye model, Fabrication error, Iterative Fourier transform algorithm, Numerical Analysis, Phase-averaging, Pixel size, Random phase mask