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http://dx.doi.org/10.3807/KJOP.2022.33.2.067

Optimization of a Highly Efficient Narrow-viewing-angle LCD for Head-mounted-display Applications  

Wi, Sung Hee (Division of Display and Semiconductor Physics, Korea University)
Kang, Min Jin (Department of Applied Physics, Korea University)
Hwang, Eui Sun (Department of Applied Physics, Korea University)
Baek, Gi Hyeon (Department of Applied Physics, Korea University)
Kim, Jin Hwan (LMS co., Ltd.)
Park, Hyeon Uk (LMS co., Ltd.)
Cheong, Byoung-Ho (Division of Display and Semiconductor Physics, Korea University)
Publication Information
Korean Journal of Optics and Photonics / v.33, no.2, 2022 , pp. 67-73 More about this Journal
Abstract
In a head-mounted display (HMD) for virtual-reality applications, a narrow viewing angle is preferred to the usual, wide viewing angle because the HMD is positioned close in front of the user's eyes, and the display position is fixed. In this paper, we propose a new back-light unit (BLU) for implementing a narrow viewing angle, which is suitable for a HMD. By optimizing the scattering patterns in the light-guide-plate and inverse-prism structures, the viewing angle and correlations between structural parameters in the BLU components are analyzed with ray-tracing simulations. As a result, a double-angle inverse-prism structure incorporating the scattering patterns of a light-guide plate is chosen, which results in a 14% increase in center luminance, a 16% decrease in the vertical viewing angle, and a light efficiency of up to 70%, compared to a conventional BLU. Thus, the new BLU system is expected to be applied in a high-efficiency liquid crystal display.
Keywords
Head-mounted display; Liquid crystal display; Viewing angle control; Optical simulation;
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