18888242. LIGHTING DEVICE (Japan Display Inc.)
LIGHTING DEVICE
Organization Name
Inventor(s)
LIGHTING DEVICE
This abstract first appeared for US patent application 18888242 titled 'LIGHTING DEVICE
Original Abstract Submitted
The incident surface is the inner surface of a recess including a bottom surface and an inwardly convex inner side. A tangent line on the free-form curve forms a smaller angle with the optical axis at a point closer to the bottom surface and a larger angle with the optical axis at a point farther from the bottom surface. The free-form curve has a curvature that is not constant. The curvature is maximized at a depth of one-third or less of a depth of the recess. The light enters the bottom surface only at a light distribution angle of three degrees. The light enters the inner side at a light distribution angle of more than three degrees. Light incident on the bottom surface exits through the emitting surface. Light incident on the inner side reflects off the outer side and exits through the emitting surface.