Patent ID: 7954975

Claim:
A refraction-type LED (Light Emitting Diode) ceiling lamp, especially a plate-type ceiling lamp used on an indoor ceiling with a limited projection angle to project brilliance on a limited area on a ground, comprising a fiber light guide plate roughly in a symmetric polygonal shape, a side of which is a reflection surface and the other side of which is a refraction surface, the reflection surface being further provided with reflection elements, at least two opposite sides of the light guide plate being provided respectively with an entrance surface; a frame, which is provided with plural LED exciting elements arranged in a series, encloses the light guide plate at positions opposite to exterior sides of the entrance surfaces and is capable of conducting heat to expel out waste heat of the LED exciting elements; a light diffuser plate which is assembled at the refraction surface of the light guide plate; a reflection plate which is assembled at the reflection surface of the light guide plate; plural reflection elements, which are assembled at the reflection surface of the light guide plate and are spherical bodies protruded outward, with inner spheres forming inner reflection curves, a chip size decreasing gradually from a breadth center of the light guide plate toward the entrance surface, and a gap between neighboring reflection elements increasing gradually from the breadth center of the light guide plate toward the entrance surface; and an electronic drive circuit which provides working electricity required by the LED exciting elements.