| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting device capable of emitting illumination light with a large amount of light of a linear polarization component. <P>SOLUTION: The lighting device 1 is provided with a light source 10, a light guide plate 20 which makes light from the light source 10 enter from the side face and emits from the front surface, and a reflecting means 30 arranged on the rear surface side of the light guide plate 20. The light guide plate 20 emits light so that it has a peak of luminance or luminous intensity at an emitting angle inclined to a normal of the front surface, and the light guide plate 20 has birefringence, and a part of light emitted at an emitting angle with a peak of luminance or luminous intensity enters aslant into the front surface at a smaller angle than a critical angle on the front surface of the light guide plate 20 and is reflected into the light guide plate, and then, goes to the rear surface side of the light guide plate 20 to be reflected by the rear surface of the light guide plate and the reflecting means, and returns again to the front surface. At this time, the polarization component is converted so that a P polarized component may be more than an S polarized component and is emitted from the front surface. <P>COPYRIGHT: (C)2011,JPO&INPIT |
