| 摘要 |
PROBLEM TO BE SOLVED: To obtain a side light plane-light-source device of high display quality for maintenance and positioning use wherein irregularity in brightness caused by convex parts of a light guide plate is reduced. SOLUTION: This side light plane-light-source device is made up of at least a light source and a light guide plate where light from the light source enters a light entrance plane of the light guide plate and outgoes from an outgoing plane crossed with the light entrance plane at right angles, wherein the light guide plate is equipped with convex parts on side faces crossed with the light entrance plane at practically right angles in order to hold or position in a frame or a box and the like, and as at least one part of the convex parts is made up of light diffusing area, the light reached the convex parts is diffused, and therefore the irregularity in brightness that occurs near the convex parts can be reduced. |
