Kabushiki Kaisha Toyota Jidoshokki

Eiki Niida

Norihito Takeuchi

Yasuya Mita

Fumikazu Isogai

Tomoyoshi Motohiro

Yasuhiko Takeda

Tatsuo Fukano

A light guiding plate guides light from a light source and irradiates the light onto a display portion. The light guiding plate has an exit plate facing the display portion, and a reflection-exit plane opposite to the exit plane. The reflection-exit plane has a first end intersecting an incidence plane and a second end intersecting an opposite end plane. An inclination angle, defined by the exit plane and a line that contains the first end and the second end, is greater than 0.20&#xb0; and less than 0.75&#xb0;. The reflection-exit plane includes a light admission portion that reflects light entering through or reflected on the incidence plane to the exit plane.

Light guiding plate for front light

A light guiding plate guides light from a light source and irradiates the light onto a display portion. The light guiding plate has an incidence plane, which permits light to enter the light guiding plate, an opposite and plane opposite to the incidence plane an exit plane facing the display portion, and a reflection-exit plane opposite to the exit plane. A plurality of grooves are formed on the reflection exit plane. In any adjacent pair of the grooves, the depth of the groove closer to the opposite end plane is equal to or greater than the depth of the groove closer to the incidence plane. The depth of the grooves substantially increase from the incidence plane toward the opposite end plane. This improves the uniformity of brightness distribution.

Wedge plate type light guiding plate for front light

A light guiding plate guides light from a light source and irradiates the light onto a display portion. The light guiding plate has an incidence plane, an opposite end plane opposite to the incidence plane, an exit plane facing the display portion, and a reflection-exit plane opposite to the exit plane. A plurality of grooves are formed on the reflection-exit plane. The depth of the grooves monotonously increases from the incidence plane toward the opposite end plane. Each groove is defined by intersecting first and second planes. In each groove, the angle defined by the first plane and the exit plane is substantially equal to that of the other grooves. In each groove, the angle defined by the first plane and the second plane is substantially equal to that of the other grooves. This waveguide increases the brightness and improves the uniformity of brightness distribution.

Wedge plate type light guiding plate for front light and method for manufacturing the light guiding plate

A light guiding plate guides light from a light source to illuminate a liquid crystal cell. A reflector reflects light from the light source. A first surface and a second surface selectively transmits or reflects light. A first region is formed on the first surface at a location that is relatively near the light source. The first region includes a first inclined face and a second inclined face. The first inclined face reflects light from the light source to guide light to the reflector. The second inclined face reflects light from the light source to the second surface so that the second surface emits light. A second region is formed on the first surface at a location that is relatively far from the light source. The second region includes a third inclined face and a fourth inclined face. The third inclined face reflects light from the light source to the second surface so that the second surface emits light. The fourth inclined face reflects light reflected by the reflector to the second surface so that the second surface emits light.

Growing community of inventors

Kariya, Japan

Eiki Niida