Mitsubishi Electric Corporation

Yuji Tsuchiyama

Akimasa Yuuki

Seiji Sakai

Kenji Itoga

Naoko Iwasaki

Takafumi Kokusho

It is an object of the invention to provide a technique capable of suppressing variations in luminance in the vicinity of a light entrance surface of a light guide plate. An illumination device includes a point light source, and a light guide plate having a side surface serving as a light entrance surface opposed to the point light source, and a main surface serving as a light exit surface. The light entrance surface of the light guide plate is provided with unevenness formed by arraying at predetermined pitches a plurality of protrusions each projecting from the light entrance surface and extending in a direction perpendicular to the light exit surface. Each of the top surface and the bottom surface of the unevenness is provided with a plurality of micro protrusions each extending in the direction perpendicular to the light exit surface and having a height smaller than the above protrusion.

Growing community of inventors

Tokyo, Japan

Yuji Tsuchiyama