| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a planar light source using a wedge-shaped prism light guide plate of high luminance and with uniform in-plane luminance, and to provide a liquid crystal display equipped with the same. <P>SOLUTION: The planar light source is provided with a flat-plate light guide plate 4, a first reflecting plate adjacently arranged at an opposed face 4d, a light source 6 adjacently arranged at a light-incident face 4a, and a second reflecting plate 5 adjacently arranged at a reflecting face 4c. The reflecting face 4c is slanted against the light-incident face 4a by a given angle, and the opposed face 4d is slanted against a light-outgoing face 4b by a given angle. On the reflecting face 4c, a plurality of equivalent-shape groove structures with a ridge line nearly parallel with the light-incident face 4a and with a cross-section shape nearly triangular are formed at a given interval with an interposition of a flat face, and, when an angle made by the light-outgoing face 4b and the reflecting face 4c is denoted by θ, a depth of the groove structure 8 is denoted by H, a maximum value and a minimum value of intervals of the groove structures 8 are denoted by d<SB>max</SB>, d<SB>min</SB>, respectively, an incident-face side basic angle and an opposed-face side basic angle of the triangle of the groove structure 8 are denoted by α, β, respectively, and an angle made by a normal of the light-outgoing face 4b and the opposed face 4d is denoted by Ω, formula (7) and formula (11) are satisfied. <P>COPYRIGHT: (C)2011,JPO&INPIT |
