Title:
LIGHT SOURCE DEVICE AND INFORMATION DISPLAY SYSTEM IN WHICH SAME IS USED
Document Type and Number:
WIPO Patent Application WO/2021/049107
Kind Code:
A1
Abstract:
The present invention is a light source device that supplies light having a specific polarization direction to a video display device, wherein the light source device comprises a dot-patterned or planar light source, an optical means for reducing the angle at which light diverges from the light source, and a light guide having a reflective surface for reflecting the light from the light source and propagating the light to the video display device. The reflective surface of the light guide is positioned opposing the video display device. A reflection-type polarization plate and a phase difference plate are positioned, in sequence from the video display device side, between the video display device and the reflective surface. Light having a specific polarization direction, reflected by the reflection-type polarization plate, is made to pass through the phase difference plate, reflected by the reflective surface of the light guide, and made to pass through the phase difference plate, whereby the polarization direction is converted, light having a specific polarization direction is propagated to the video display device, and some or all of the divergence angle of a light beam entering the video display device from the light source is controlled according to the surface roughness and the shape of the reflective surface provided to the light source device.
Inventors:
HIRATA KOJI (JP)
SUGIYAMA TOSHINORI (JP)
FUJITA KOJI (JP)
TAKAGI EIJI (JP)
SUGIYAMA TOSHINORI (JP)
FUJITA KOJI (JP)
TAKAGI EIJI (JP)
Application Number:
PCT/JP2020/021995
Publication Date:
March 18, 2021
Filing Date:
June 03, 2020
Export Citation:
Assignee:
MAXELL LTD (JP)
International Classes:
F21S2/00; F21V9/14; G02F1/13; G02F1/13357
Domestic Patent References:
| WO2013080488A1 | 2013-06-06 |
Foreign References:
| JP2015210844A | 2015-11-24 |
Attorney, Agent or Firm:
TSUTSUI & ASSOCIATES (JP)
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