Surface-emitting device, front light, and liquid crystal device
AssigneeSeiko Epson Corporation
InventorHiroshi Wada
Life of this patent
Estimating the term…
Abstract
There is provided a surface-emitting device, such as a front light, in which visibility is not deteriorated even when a point light source, such as a light-emitting diode, is used. A surface-emitting device 20 forming a front light includes point light sources 21, such as light-emitting diodes, a transmissive light guide plate 22 made of acrylic resin, polycarbonate resin, or the like by injection molding or by other methods, a transmissive light-scattering plate 23 bonded onto an end face 22d of the light guide plate 22 opposite from the side of an end face 22c where the point light sources 21 are placed, and a reflection plate 24 bonded onto the surface of the light-scattering plate 23.
Claims13
A surface-emitting device, comprising:
- a transmissive light guide plate that emits from its surface light propagating therein in a first direction along its plate plane, the front surface of said light guide plate comprising a convex portion or a concave portion having an inclined face that emits light from the front surface;
- a light source placed adjacent to a first end of said light guide plate that introduces light into said light guide plate in a second direction different from the first direction;
- and
- a reflecting layer, disposed at a second end of said light guide plate different from the first end where said light source is placed, that reflects light which propagates inside said light guide plate in the second direction in nearly the first direction, inside said light guide plate,
- said convex portion or said concave portion of said front surface of said light guide plate comprising a gently inclined face formed to face the second direction, as viewed from the inside of said light guide plate, and inclined at a small angle to the rear face of said light guide plate, and a steeply inclined face formed to face the first direction, as viewed from the inside of said light guide plate, and inclined at a large angle to the rear face of said light guide plate.
A front light, comprising:
- a transmissive light guide plate that emits from front surface light propagating therein in a first direction along its plate plane, the front surface of said light guide plate comprising a convex portion or a concave portion having an inclined face that emits light from the front surface;
- a light source placed adjacent to a first end of said light guide plate that introduces light into said light guide plate in a second direction different from the first direction, said light guide plate allowing sight therethrough;
- and
- a reflecting layer disposed at a second end of said light guide plate different from said first end where said light source is placed, that reflects light which propagates inside said light guide plate in the second direction in nearly the first direction, inside said light guide plate,
- said convex portion or said concave portion of said front surface of said light guide plate comprising a gently inclined face formed to face the second direction, as viewed from the inside of said light guide plate, and inclined at a small angle to the rear face of said light guide plate, and a steeply inclined face formed to face the first direction, as viewed from the inside of said light guide plate, and inclined at a large angle to the rear face of said light guide plate.
Dependencies are inferred from the claim text.