Omron Corporation

Takako Ishikawa

Masayuki Shinohara

Kazuhide Hirota

Yasuhiro Tanoue

Yoshihiro Ueno

Norikazu Kitamura

Gouo Kurata

Koichi Takemura

Jun Kishimoto

Hiroyuki Miyamoto

Morihisa Ota

Yukihiro Takahashi

Takuma Iwase

A light guide plate has a light introduction part having an end face configured to have light incident thereon, and a light guide plate body disposed continuously to the light introduction part and comprising a thickness smaller than a maximum thickness of the light introduction part. The light guide plate body has a light emitting surface that emits the light incident from the end face. The light introduction part comprises an inclined face disposed on at least one side of the light guide plate. The inclined face is inclined smoothly from a surface of a part thicker than the light guide plate body toward an end of the light guide plate body. An optical pattern part has a linear pattern element is disposed near a region in a proximity of the inclined face in a face on a light exit side of the light guide plate body.

Surface light source device and its light guide plate

A light guide plate has a light introducing portion configured to confine light that is incident from an end surface, and a light guide-plate main body configured to emit incident light to an outside from a light emitting surface and provided continuously with the light introducing portion in a thickness smaller than a maximum thickness of the light introducing portion. The light introducing portion has an inclined surface inclined toward the light guide-plate main body from a surface having a larger thickness than a thickness of the light guide-plate main body, on at least one of a surface at a light emission side and a surface opposite to the surface at the light emission side.

Light guide plate and surface light source device

A light guide plate has a light introduction part having an end face configured to have light incident thereon, and a light guide plate body provided continuously to the light introduction part and comprising a thickness smaller than maximum thickness of the light introduction part. The light guide plate body has a light emitting surface configured to emit light incident from the end face. A directivity conversion pattern is provided on at least one of a face on a light exit side and a face opposite to the face. The directivity conversion pattern converts directivity spread in a thickness direction of the light introduction part to a directivity characteristic which is inclined in a direction parallel to a face direction of the light introduction part. A light reflection wall is provided on the end face.

A light guide plate has a light introducing portion configured to confine light that is incident from an end surface, and a light guide-plate main body configured to emit incident light to an outside from a light emitting surface and provided continuously with the light introducing portion in a thickness smaller than a maximum thickness of the light introducing portion. The light introducing portion has an inclined surface inclined toward the light guide-plate main body from a surface comprising a larger thickness than a thickness of the light guide-plate main body, on at least one of a surface at a light emission side and a surface opposite to the surface at the light emission side. The inclined surface has a main-inclined surface configured to be positioned in front of a light source arranged opposite to the end surface.

A light guide plate has a light incident surface configured to be arranged facing a point light source for introducing light from the point light source, a light outputting surface that outputs the light to an outside of the light guide plate, a light introducing section for confining the light from the point light source entered from the light incident surface, and a light guide plate main body having a thickness smaller than a maximum thickness of the light introducing section and being arranged to be continuous with the light introducing section, for outputting the confined light to the outside of the light guide plate from the light outputting surface by a light outputting element.

Surface light source apparatus

An area light source device that is capable of evenly emitting light by reducing leakage in the vicinity of the light source, and enhancing the light emission luminance by exiting light of narrower directional characteristics. A light guide substrate includes a light introducing section and a light guide plate main body. Diffusion patterns are provided at the light exit surface of the light guide plate main body. A low refraction index layer is formed at the lower surface of the light guide plate main body, and a reflection layer is formed at the lower surface of the low refraction index layer. The point light source is positioned facing an end face of the light introducing section. A directivity conversion unit is arranged on the upper surface of the light introducing section. The directivity conversion unit is configured by radially arraying a directivity conversion pattern having a V groove shape.

Area light source device and liquid crystal display device

A surface light source device includes a point source of light and a light guide plate causing light from the point source of light introduced from a light incident end face and emitted from a light emission surface to outside. The light guide plate is formed of a light introducing portion provided at an end of a light guide plate body. The point source of light is placed facing the light incident end face positioned at an end face of the light introducing portion. Along a region of the light introducing portion adjacent to the light guide plate body, a directivity converting portion is provided. The directivity converting portion is configured by arranging V-grooved directivity conversion patterns in an arc shape. A region of the light introducing portion has a thickness equal to that of the light guide plate body and has a surface positioned in the same plane.

Surface light source device and liquid crystal display device

An area light source device that is capable of more evenly emitting light and capable of enhancing the light emission luminance by exiting light of narrower directional characteristics. A light guide substrate includes a light introducing section and a light guide plate main body for exiting the light from a light exit surface. A number of diffusion patterns are formed at the light exit surface. A low refraction index layer is formed at the lower surface of the light guide plate main body, and a reflection layer is formed at the lower surface of the low refraction index layer. The point light source is arranged at a position facing the end face of the light introducing section. A tapered portion inclined to gradually increase the thickness of the light introducing section the farther away from the light source is arranged on the upper surface of the light introducing section.

A light guide plate () includes a light introducing section (), which is at a position facing a point light source (), for confining light from the point light source, and a light guide plate main body (), which has a thickness smaller than a thickness at an end of the light introducing section on the point light source side, for outputting the confined light to an outside from a light outputting surface by light outputting means (). The light introducing section () has an inclined surface (), which is inclined from a surface of the light introducing section towards a surface of the light guide plate main body (). The inclined surface () has a directivity converting pattern () for converting a directivity expansion in a thickness direction of the light guide plate of the light entered to the light introducing section () to directivity characteristics tilted towards a direction parallel to a surface direction of the light guide plate. The directivity converting pattern () has a structure in which a plurality of V-shaped groove structures () are lined.

Growing community of inventors

Kusatsu, Japan

Takako Ishikawa