Lighting device and liquid crystal display

• Main Authors: OIZUMI MITSUO, SUGIURA TAKURO, YAMASHITA TATSUMARO
• Format: Patent
• Language: English
• Published: 20.08.2003
• Edition: 7
• 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; FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMSTHEREOF; HEATING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21Sand F21V, RELATING TO THEFORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THELIGHT EMITTED; LIGHTING; MECHANICAL ENGINEERING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHERARTICLES, NOT OTHERWISE PROVIDED FOR; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; WEAPONS

One major surface of a light guide plate (12) is formed, in stripe form in a plan view, with a plurality of prism grooves (14) each consisting of a slight slope and a steep slope. The inclination angles of the slight slope and the steep slope are in ranges of 1 DEG to 10 DEG and 41 DEG to 45 DEG , respectively. The width of the steep slope in the one major surface of the light guide plate increases as the position goes away from a light incident surface of the light guide plate in such a manner that the width of the steep slope amounts to 1.1 to 1.5 at a position farthest from the light incident surface if it is assumed that the width of the steep slope is equal to 1.0 at a position closest to the light incident surface.