Alps Electric Co., Ltd.

Takuro Sugiura

Mitsuo Ohizumi

Tatsumaro Yamashita

Hideaki Nagakubo

Koichi Yamamoto

Mituso Ohizumi

Ohizumi Mitsuo

A light guiding plate comprises a pair of main surfaces opposite to each other, and an end surface on which light emitted from a light source is incident. One of the pair of main surfaces has a plurality of prisms. Each of the prisms has a first surface which is relatively close to the end surface and has a relatively gentle slope, a second surface which is relatively distant from the end surface and has a relatively steep slope, and a third surface located between the first surface and the second surface, and an angle between the second surface and the third surface is an acute angle.

Light guiding plate including a plurality of prisms, surface emitting device using light guiding plate, and liquid crystal display device using light guiding plate

At the light emission surface of a light-guiding plate, first and second grooves and second grooves are formed. Each of the first grooves has a pair of slope parts, and each slope part has an easy slope and a steep slope. The second grooves intersect the first grooves at predetermined angles. Each of the second grooves has a pair of slope parts, and each slope part has an easy slope and a steep slope. With the first grooves and the second grooves intersecting each other, at the light emission surface, a plurality of minute prisms are formed in flat quadrangular pyramid shapes to be dented toward the surface opposite to the light emission surface of the light-guiding plate.

Surface emitting device, backside illumination device, and liquid crystal display device

A stereoscopic display device is provided. The stereoscopic display device includes an optical waveguide member and a first main surface and a second main surface. The first and second main surfaces face each other. A first light path changing member is provided on at least one of the first and second main surfaces, and is operative to change the path of light guided by the optical waveguide member. A second light path changing member is provided on at least one of the first and second main surfaces, and is operative to change the path of the light guided by the optical waveguide member. A reflector body is disposed so as to face the second main surface and reflects the light emitted from the second light path changing member to the first main surface.

Lighting system

A front light including a light-guiding plate for receiving light from a light-entering surface and emitting the light from a light-emitting surface, an intermediate light-guiding body disposed along the light-entering surface, light-emitting elements disposed at longitudinal ends of the intermediate light-guiding body. A side surface of the intermediate light-guiding body adjacent to the light-entering surface of the light-guiding plate is a light-emitting surface for emitting light from the light-emitting elements to the light-guiding plate. A side surface opposite to the light-emitting surface is a reflective surface. The total length of the intermediate light-guiding body and the light-emitting elements is the same as the width of the light-guiding plate, the length of at least the light-emitting surface of the intermediate light-guiding body is the same as the width of the light-guiding plate, and the length of the reflective surface is smaller than the length of the light-emitting surface.

Surface-emitting device and liquid crystal display apparatus

A surface emitting device includes a light guiding plate, a light source, and a prism sheet. The light guiding plate is provided with prism portions each having a slight inclined plane and a steep inclined plane arranged closer to one edge than the slight inclined plane. A plurality of light refracting portions each having a refractive surface and a reflective surface are provided on an incident surface of the prism sheet. Light introduced into the light guiding plate from the light source is emitted from the slight inclined plane and is then incident on the light refracting portion. The light is introduced into the prism sheet by the refracting surface and is then reflected from the reflective surface to be emitted.

Prism sheet, illuminating device, surface emitting device, and liquid crystal display device

An illumination device is constructed such that light illuminated by a light emitting element and transmitted through one side surface of a light guiding plate via an intermediate light guide is introduced into the light guiding plate and the light propagating in the light guiding plate is emitted from an output surface of the light guiding plate so as to illuminate a liquid crystal display unit (an illumination object) disposed behind the light guiding plate, such that a part of the light guiding plate, through which the liquid crystal display unit is displayed in a transmissive manner, serves as a display area, and such that the light guiding plate is formed so as to extend beyond the display area of the liquid crystal display unit and towards the light emitting element, along the longitudinal direction of the intermediate light guide.

Single-light source illumination device and liquid crystal display device using the same

A front light of the invention has a light guide plate, an intermediate light guide disposed along the side end surface, and a light emitting device disposed on an end surface thereof. The pitch between grooves having a wedge shape in cross section formed on a backside of the light guide on the opposite side of the light guide plate is formed so as to be linearly varied with respect to the distance from an end surface disposed with the light emitting device to the groove. The depth of the groove is formed more deeply as the grooves are positioned more apart from the end surface. In the distribution of the depth of the groove with respect to the distance from the end surface to the groove, there are a first area where the depth of the groove is linearly increased with respect to the distance from the end surface disposed with the light emitting device to the groove, and a second area formed apart from the light emitting device more than the first area in which the increasing rate of the depth of the groove with respect to the distance from the end surface is greater than that in the first area.

Lighting device and liquid crystal display device

In a front light, an intermediate light guide protrudes from a light guide plate toward a light emitting element in the direction along a light incident face of the light guide plate. A side face of the intermediate light guide opposing the light incident face serves as an emergent face from which light from the light emitting element is emitted to the light guide plate, and an outer side face remote from the emergent face serves as a reflecting face for reflecting light propagating inside the intermediate light guide. The outer side face of the intermediate light guide is provided with a prism face having a plurality of grooves of wedge-shaped cross section, and a reflective film formed thereon. The prism face is provided distant from an end face of the intermediate light guide close to the light emitting element.

Illumination device and liquid crystal display device

The invention includes a bar-shaped light source and a light guiding plate for entering a light of the light source from the lateral end surface and emitting the light from the emissive surface, wherein a cover having the bracket shaped cross sectional shape for covering the bar-shaped light source and one portion of the light guiding plate supports the light source at the lateral side portion of the light guiding plate, the bracket-shaped cover made of a spring material in a shape of clip pinches the light guiding plate through a pressing portion on the inner surface of the cover, and the projections extended on the both sides of the cover are adopted to position the light guiding plate accurately in the width direction.

Surface emitting device and liquid crystal display

A surface-emitting device includes a light guide panel, a light guide placed along one end face of the light guide panel, and light sources placed at ends of the light guide. A side face of the light guide facing the end face of the light guide panel serves as an emergent surface for applying light from the light sources to the light guide panel, and a side face remote from the emergent surface serves as a reflecting surface on which concave grooves for reflecting light propagating inside the light guide are periodically formed at a predetermined pitch. The depth of the concave grooves increases toward the center of the light guide, and the angle formed between two inclined faces that constitute each groove is within the range of 105&#xb0; to 115&#xb0;.

Surface-emitting device and liquid crystal display device

An illumination device includes a light source composed of a light emitting element and an intermediate light guide, and a light guide plate that receives light from the light source through a light incident face and that emits the light propagating therein from an emergent surface. A reflecting surface of the light guide plate has a plurality of prism grooves formed in stripes in plan view, each prism groove having a gently inclined face and a sharply inclined face inclined more sharply than the gently inclined face. A &#x3b8;-coefficient, which is the product of the number of the sharply inclined faces per unit length of the light guide plate, and the length of the sharply inclined faces, is increased away from the light source in the light guide plate.

A front light includes a light guide panel, a light guide bar placed along an end face of the light guide panel, and light-emitting elements placed at both ends of the light guide bar. A cover member including a reflecting-surface covering portion for covering an end on the reflecting-surface side of the light guide panel, a light-guide covering portion for covering the light guide bar, and an emergent-surface covering portion for covering an end on the emergent-surface side of the light guide panel is mounted so as to cover at least the light guide bar and the ends of the light guide panel. The reflecting-surface covering portion protrudes longer in the light guide direction than the emergent-surface covering portion.

Surface-emitting device and liquid crystal display device with enhanced utilization efficiency of light from light source

One major surface of a light guide plate is formed, in stripe form in a plan view, with a plurality of prism grooves each consisting of a slight slope and a steep slope. The inclination angles of the slight slope and the steep slope are in ranges of 1&deg; to 10&deg; and 41&deg; to 45&deg;, respectively. The width of the steep slope in the one major surface of the light guide plate increases as the position increases from a light incident surface of the light guide plate such that a ratio of the width of the steep slope at a position farthest from the light incident surface to the width of the steep slope at a position closest to the light incident surface is 1.1 to 1.5.

Growing community of inventors

Fukushima-ken, Japan

Takuro Sugiura