SURFACE LIGHT SOURCE DEVICE AND IMAGE DISPLAY DEVICE

• Main Authors: INOUE TATSUAKI, ASANO EIJI, KITANO KEIKO
• Format: Patent
• Language: English; Japanese
• Published: 18.05.2017
• Subjects: BLASTING; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; HEATING; LIGHTING; MECHANICAL ENGINEERING; NON-LINEAR OPTICS; NON-PORTABLE LIGHTING DEVICES; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SYSTEMS THEREOF; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLEEXTERIORS; WEAPONS

PROBLEM TO BE SOLVED: To provide an inverted prism type surface light source device capable of effectively preventing a wet-out, and an image display device to which such a surface light source device is applied.SOLUTION: A surface light source device 20 comprises a light source device 28 and a prism sheet (optical sheet) 30. The light source device 28 includes a light source part 26 and a light guide part 21. The light guide part 21 has a plurality of light source-side unit optical elements 24a which are arranged side by side with one another and convex, and the plurality of light source-side unit optical elements 24a emit light from the light source part 26. The prism sheet 30 has a plurality of unit prisms (sheet-side unit optical elements) 32a which are arranged side by side with one another and convex. The plurality of unit prisms 32a come into contact with at least some of the plurality of light source-side unit optical elements 24a, and light from the light guide part 21 impinges thereon. Tops of the plurality of light source-side unit optical elements 24a are not located on the same plane. Tops of the plurality of unit prisms 32a are not located on the same plane.SELECTED DRAWING: Figure 1 【課題】ウェットアウトを有効に防ぐことができる逆プリズム型の面光源装置及びそのような面光源装置を応用した画像表示装置を提供する。【解決手段】面光源装置２０は、光源デバイス２８及びプリズムシート（光学シート）３０を備える。光源デバイス２８は、光源部２６及び導光部２１を含む。導光部２１は、相互に並んで配置される凸状の複数の光源側単位光学要素２４ａを有し、複数の光源側単位光学要素２４ａは光源部２６からの光を出射する。プリズムシート３０は、相互に並んで配置される凸状の複数の単位プリズム（シート側単位光学要素）３２ａを有する。複数の単位プリズム３２ａは、複数の光源側単位光学要素２４ａのうちの少なくとも一部と接触し、導光部２１からの光が入射する。複数の光源側単位光学要素２４ａの頂部は、同一平面上には位置しない。複数の単位プリズム３２ａの頂部は、同一平面上には位置しない。【選択図】図１