Panel lighting appliance

Abstract

Abstract PURPOSE: To sufficiently uniformize brightness on a luminescent surface by arranging a light source lamp and a plate-shaped light guide, using the surface and the back of the light guide as a light lead through surface and a light diffusing surface having the specified constitution, and installing the light diffusing surface above the light lead through surface. CONSTITUTION: A straight fluorescent lamp 1 for a light source and a light guide 2 are arranged within a box body 10. The light guide 2 is made of a transparent material, the surface acts as a light lead through surface 21 and the back acts as a light diffusing surface 22. The light lead through surface 21 is convex, and the distance to the light diffusing surface 22 becomes maximum in the middle part, and becomes minimum in the most distant position from the lamp 1. The light diffusing surface 22 consists of a reflecting part 23 and a transmitting part 24 parallel each other, the distribution density of the reflecting part 23 varies with the distance from the lamp 1, becomes maximum in the middle part, and monotonously increases with distance in the other part. Light incident to the light guide 2 from the lamp 1 is totally reflected on the light lead through surface 21, then reflected on the light diffusing surface 22, and outgoes through the light lead through surface 21 and a diffusing surface 3.

Inventors

• 👤 Tadashi Murakami
• 👤 Toshihiko Sakaguchi
• 👤 Tadahiro Otsuka

Bibliographic Details