| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a planar lighting device capable of obtaining illumination light excellent in narrow directivity and brightness uniformity, in the planar lighting device equipped with a point light source and a light guide plate. <P>SOLUTION: The planar lighting device 10 is provided with a light guide plate 12, and a point light source 14 arranged at a side end face 12a of the light guide plate 12. A brightness distribution control lens 16 for controlling spread angles of light emitted from the point light source 14, and a Fresnel lens 18 for advancing light spread by the brightness distribution control lens 16 through an inside of the light guide plate 12 as parallel light are arranged between the light guide plate 12 and the point light source 14, sequentially from a point light source 12 side. <P>COPYRIGHT: (C)2012,JPO&INPIT |
