Mitsubishi Rayon Company, Limited

Issei Chiba

Tomoyoshi Yamashita

Yasuko Hayashi

Masaharu Oda

Makoto Oe

Makoto Ohe

A surface light source apparatus includes a primary light source (), an optical guide () for guiding light emitted from the primary light source and having a light incoming surface () and a light outgoing surface (), a light deflection element () arranged adjacent to the light outgoing surface of the optical guide and having a light incoming surface () and a light outgoing surface (), and a light diffusion element () arranged adjacent to the light outgoing surface of the light deflection element. The light incoming surface () of the light deflection element has a plurality of prism strings arranged substantially parallel to each other and each having two prism surfaces. At least one of the prism surfaces of these prism strings has a prism surface consisting of at least two planes having different inclination angles. As the plane approaches the light going surface, the inclination becomes larger.

Light deflection element and light source apparatus using the same

A planar light source system having an LED () serving as a primary light source of substantially point-shaped light source, a light guide () having a light incident face on which light emitted from the LED () is incident and a light emission face () from which light guided through the light guide () is emitted, a light deflecting device () for controlling the direction of the emission light from the light guide (), and a reflection sheet (). LED () is disposed at a corner portion of the light guide (), and many elongated prisms () are arranged substantially arcuately in parallel to each other on the light incident surface () of the light deflecting device () so as to surround LED ().

Planar light source system and light deflecting device therefor

A light source device, comprising a light guide () having two light incident surfaces opposed to each other for receiving incident light radiated from a primary light source and a light outgoing surface () for emitting the incident light and a light deflection element () disposed adjacent to the light emitting surface side of the light guide, the light deflection element () further comprising a light receiving surface () for receiving incident light and a light emitting surface () positioned on the opposite side thereof and emitting the incident light, wherein a plurality of elongated prisms formed of two prism faces are disposed on the light receiving surface () generally parallel with each other, the prism surfaces are formed of at least two faces () with different inclination angles, and the inclination angles are larger for the faces positioned nearer the light emitting surface ().

Light source device and light polarizing element

A light source device comprising at least a primary light source (), a light guide () guiding light beamed from the primary light source and having a light incident surface () and a light outgoing surface (), an optical deflector () disposed adjacent to the light guide's light outgoing surface and having a light incident surface () and a light outgoing surface (), and a light diffuser () disposed adjacent to the optical deflector's light outgoing surface and having a light incident surface () and a light out going surface (), wherein the optical deflector's light incident surface is formed with a plurality of rows of prisms arranged in parallel to each other, and the light diffuser has the full width half maximum of an outgoing light intensity of 1&#x2013;13 degrees when parallel rays of light are incident, whereby providing a light source device excellent in light utilization efficiency of a primary light source, and also excellent in viewing angle characteristics and quality as an image forming illumination without sacrificing high brightness characteristics.

Light source device

A light source device having a light guide () for guiding light emitted from a primary light source and emitting light obliquely from a light emission face () thereof, and a light deflecting device () disposed so as to be adjacent to the light emission face. Plural elongated prisms are arranged in parallel to one another at a light incident surface () of the light deflecting device. Virtual elongated prisms (I) each having a vertical angle &#x3b8; of 50 to 70&#xb0; arranged in the same arrangement pitch as the elongated prisms are assumed so that the peak emission light in the light emission distribution of light emitted from the light emission face is incident on one virtual prism face of the virtual elongated prism, internally totally reflected by another virtual prism face and then emitted in a desired direction from a light emission surface () of the light deflecting device. A prism face of each elongated prism at the far side from the primary light source is designed to have a convex surface shape with respect to the shape of the virtual elongated prism. The value (r/P) of the radius of curvature r normalized by the arrangement pitch P is equal to 7 to 30, and the ratio (d/P) of the maximum distance between the convex-surface-shaped prism face of the elongated prism and the virtual prism face to the arrangement pitch P is equal to 0.05 to 5%.

A light-source device having a light guide () for guiding light emitted from a primary light source and emitting light obliquely from a light emission face () thereof, and a light deflecting device () disposed so as to be adjacent to the light emission face. Plural elongated prisms are arranged in parallel to one another at a light incident surface () of the light deflecting device. Virtual elongated prisms (I) each having a vertical angle &#x3b8; of 50 to 70&#xb0; arranged in the same arrangement pitch as the elongated prisms are assumed so that the peak emission light in the light emission distribution of light emitted from the light emission face is incident on one virtual prism face of the virtual elongated prism, internally totally reflected by another virtual prism face and then emitted in a desired direction from a light emission surface () of the light deflecting device. A prism face of each elongated prism at the far side from the primary light source is designed to have a convex surface shape with respect to the shape of the virtual elongated prism. The value (r/P) of the radius of curvature r normalized by the arrangement pitch P is equal to 7 to 30, and the ratio (d/P) of the maximum distance between the convex-surface-shaped prism face of the elongated prism and the virtual prism face to the arrangement pitch P is equal to 0.05 to 5%.

A planar light source system having an LED ( ) serving as a primary light source of substantially point-shaped light source, a light guide ( ) having a light incident face on which light emitted from the LED ( ) is incident and a light emission face ( ) from which light guided through the light guide ( ) is emitted, a light deflecting device ( ) for controlling the direction of the emission light from the light guide ( ), and a reflection sheet ( ). LED ( ) is disposed at a corner portion of the light guide ( ), and many elongated prisms ( ) are arranged substantially arcuately in parallel to each other on the light incident surface ( ) of the light deflecting device ( ) so as to surround LED ( ).

A surface light source device, comprising a light source (,); a light conductor (,) which has a light incident face (,) on at least one side end surface thereof which confronts the light source (,), and a light emitting face (,) on one surface thereof which is substantially perpendicular to the light incident face (,); and a light angle varying sheet (,) which is disposed at a side of the light emitting face (,) of the light conductor (,), wherein at least one of the light emitting face (,) and a back surface (,) of the light conductor (,) comprises a minute structure having an average slant angle of 0.5 to 7.5 degrees. The light angle varying sheet (,) may comprise a prism sheet having a plurality of prisms (,) which are formed parallel to one another on at least one surface thereof. The minute structure may comprise a roughened surface which includes a plurality of fine convex members each having a substantially spherical surface or a plurality of prism arrays having slant surfaces which extend parallel to said light incident face (,) and which have an average slant angle of 0.5 to 7.5 degrees.

Surface light source device, and liquid crystal display device, sign display apparatus and traffic sign display apparatus using the surface light source device

A resin sheet having laminated transparent resin layers and a smooth outer surface, the refractive indexes of two resins of any adjacent two resin layers differing from each other, the interfaces among the resin layers having an uneven shape, is produced with an extrusion molding apparatus having such a structure that a plurality of transparent resins are extruded from respective separate flow passages into a composite resin flow passage to form a composite resin flow having a laminate structure with an uneven shape at the interfaces of the resin layers, and that the composite resin flow is extruded from an outlet of the composite resin flow passage. The resin sheet is used as a laminate, or a light guide of a surface light source element.

Resin sheet, process and apparatus for producing same, surface light source element and laminate

Surface light source device and liquid crystal display device sign display apparatus and traffic sign display apparatus using the surface light source device

Surface light source element and liquid crystal display device, sign

A plane light source unit which may be advantageously used as a backlighting means for a liquid crystal display device, and which includes a transparent light guide having a side end surface as a light incident surface, a surface perpendicular to the light incident surface as a light emitting surface, and a light reflecting layer provided on an opposite surface to the light emitting surface; and a second element having a large number of prism units formed on the light emitting surface of the transparent light guide which receives the light emitted from the transparent light guide and emits the light in a predetermined direction; wherein at least one of the light emitting surface and the opposite surface of said transparent light guide has a directional light emitting function which emits the incident light from the light incident surface of the transparent light guide in an oblique direction to the incident light and has a regulation function which makes the luminance of the light through the light emitting surface uniform over the whole surface thereof.

Growing community of inventors

Kanagawa, Japan

Issei Chiba