Japan Display Inc.

Japan Aviation Electronics Industry, Limited

The University of Tokyo

Masafumi Okada

Makoto Hasegawa

Nobuyuki Suzuki

Hiroshi Akimoto

Yoshihiko Nakamura

Takeo Koito

Ken Sugiyama

Takashi Ota

Koji Hiramoto

Ken Kagabu

Hiroshi Nakamoto

Michihide Shibata

Shinichi Komura

Kenji Matsumoto

Ken Onoda

Takuya Miyashita

Koji Fujisawa

Shingo Chiyoda

Tatsuya Goto

Koichi Watabe

Yohei Kimita

A lighting device according to the invention includes: a funnel shaped reflector including a first hole in which a light source is disposed, a second hole which emits light, and a reflecting curved surface connecting the first hole with the second hole, a first direction being defined as a direction of a line connecting a center of the first hole with a center of the second hole; a reflection plate, being opposed to the second hole of the funnel shaped reflector, major surface being tilted with a first angle; and a liquid crystal lens including an incident surface and opposing to the reflection plate, a major surface of the incident surface being tilted to the major surface of the reflection plate with a second angle, in which light emitted from the funnel shaped reflector is reflected at the reflection plate, and is emitted from the liquid crystal lens.

Lighting device

The incident surface is the inner surface of a recess including a bottom surface and an inwardly convex inner side. A tangent line on the free-form curve forms a smaller angle with the optical axis at a point closer to the bottom surface and a larger angle with the optical axis at a point farther from the bottom surface. The free-form curve has a curvature that is not constant. The curvature is maximized at a depth of one-third or less of a depth of the recess. The light enters the bottom surface only at a light distribution angle of three degrees. The light enters the inner side at a light distribution angle of more than three degrees. Light incident on the bottom surface exits through the emitting surface. Light incident on the inner side reflects off the outer side and exits through the emitting surface.

A lighting device capable of changing light direction includes: a light guide plate having a first side surface extending in a first direction; and LEDs at the first side surface, in which the light guide plate has a first area extending in a second direction which is a direction perpendicular to the first direction and a second area extending in the second direction and adjacent to the first area, corresponding to the first area, at least one LED is arranged at the first side surface, corresponding to the second area, at least one LED is arranged at the first side surface, a first prism array is formed under a bottom surface of the first area, and a second prism array is formed under a bottom surface of the second area, and a prism height of the second prism array is taller than a prism height of the first prism array.

A backlight includes: a light source capable of emitting light spreading in first and second directions perpendicular to each other, from an optical axis; a first cylindrical lens that refracts and brings the light closer along the first direction to the optical axis, the first cylindrical lens overlapping with the light source in a third direction perpendicular to the first and second directions; a second cylindrical lens that refracts and brings the light even closer along the first direction to the optical axis, the second cylindrical lens overlapping with the light source and the first cylindrical lens in the third direction; and a reflector that reflects and brings the light closer along the second direction to the optical axis, the reflector being positioned between the first cylindrical lens and the second cylindrical lens in the third direction, the reflector avoiding overlap with the light source.

Backlight and display device

According to one embodiment, in an illumination device, a second light guide includes a plurality of fourth projecting portions provided in a first area of a fifth main surface opposing a prism sheet, a plurality of fifth projecting portions provided in a second area of a fifth main surface, and a plurality of sixth projecting portions on a sixth main surface opposing the fifth main surface, cross-sectional shapes of the fourth projecting portions and the fifth projecting portions are scalene triangles, and the fourth projecting portions and the fifth projecting portions are arranged in respective positions line-symmetrical position with respect to each other in plan view.

Illumination device

In a backlight that includes a plurality of LEDs and a prism sheet disposed opposite to the LEDs, the prism sheet has a first surface opposite to the LEDs and a second surface on the opposite side of the first surface, a first prism having a first base and a first pitch Lis formed on the first surface, a second prism having a cross section that is scalene triangular in shape having a second base having a length L, a first base angle θ, and a second base angle θsmaller than the first base angle is formed on the second surface, and L<L

Backlight and liquid crystal display device

Disclosed is a lighting device including a light guide plate, a plurality of LEDs, a prism sheet disposed on a side toward the upper surface of the light guide plate, and a reflective sheet disposed on a side toward the lower surface of the light guide plate. The plurality of LEDs are arrayed on a side surface corresponding to a first side of the light guide plate in a first direction along the first side. The prism sheet includes a first prism array that is formed on a surface facing the light guide plate. The first prism array includes prisms that are extended in the first direction and arrayed in a second direction perpendicular to the first direction. The upper surface of the light guide plate and the prism sheet sandwich a diffusion sheet therebetween. The diffusion sheet has a haze value between 30% and 65% when measured in compliance with JIS K7361. The prisms on the first prism array have an apex angle between 55 degrees and 66 degrees.

The purpose of the present invention is to realize a lighting device of thin, low power consumption and high emitting efficiency. A concrete structure of the inventions is as follows. A lighting device including a first light guide and a second light guide stacked on the first light guide, a reflecting sheet disposed under the first light guide, and a prism sheet disposed on the first light guide, in which a concentric first prism array is formed on the prism sheet, a plurality of first LEDs are disposed along a circumferential direction of a side wall of a first hole of the first light guide, a plurality of second LEDs are disposed along a circumferential direction of a side wall of a second hole of the second light guide, and the plurality of the first LEDs and the plurality of the second LEDs are displaced in azimuth direction.

Lighting device with LED facing a disc shaped light guide

Provided is an illumination apparatus capable of forming ring-shaped irradiation light by using a simple configuration. Also provided is an illumination apparatus capable of freely changing a shape of the ring-shaped irradiation light. In order to achieve these objects, the present invention has the following means. That is, the illumination apparatus includes a first reflector having a first hole where a light source is arranged, a second hole that emits light, and a reflecting curved surface that connects the first hole and the second hole with each other, a light shield arranged at an area including a center of the second hole as seen in plan view, an opening portion formed in a ring-shaped manner between an inner edge of the second hole and an outer edge of the light shield, and a liquid crystal lens arranged so as to cover the opening portion.

Illumination apparatus

According to one embodiment, an illumination device includes red light emitting elements, green light emitting elements and blue light emitting elements opposing a first side surface of a first light guide, and the red light emitting elements, the green light emitting elements and the blue light emitting elements are disposed along the first side surface in a third direction that intersects the first direction and the second direction, and, arranged to be symmetrical with respect to a central axis of the third direction of the first side surface.

Illumination device and display device

The purpose is to realize a lighting device of thin, small light distribution angle, and less leak light. Further, the purpose is to realize a lighting device which can control light beam accurately with liquid crystal lenses. The structure of the invention is as follows. A lighting device including: a reflector cylinder including a mirror thereinside; and a liquid crystal lens assembly that is disposed at a light emitting surface of the reflector cylinder and includes a plurality of liquid crystal lenses being stacked, in which the liquid crystal lens assembly includes a light shading film which defines a light emitting area of the liquid crystal lens assembly and which is formed in parallel with the light emitting surface of the reflector cylinder.

According to one embodiment, a light emitting device includes a light guide plate with a plurality of first protrusion parts arranged along a first direction and extending along a second direction which crosses the first direction, and a prism sheet, wherein a cross-sectional shape of each of the first protrusion parts along the first direction has an apex angle between 55 degrees and 65 degrees, inclusive, the light guide plate includes a plurality of second protrusion parts which extend along the first direction and are arranged along the second direction, and a cross-sectional shape of each of the second protrusion parts along the second direction has a base angle between 1 degree and 3 degrees, inclusive.

Light emitting device and illumination device

A lighting device including a first unit and a second unit, the first unit including: a first funnel shaped reflector having a first neck, a first opening, a first reflecting surface and a first light axis, a first LED emitting a first color disposed on the first neck, a first liquid crystal lens disposed at the first opening, a second unit including: a second funnel shaped reflector having a second neck, a second opening, a second reflecting surface and a second light axis, a second LED emitting a second color disposed on the second neck, a second liquid crystal lens disposed at the second opening; a length hof the first funnel shaped reflector is same as a length of the second funnel shaped reflector, and a diameter dof the first opening is same as a diameter of the second opening, and h/dis two or more.

The purpose of the present invention is to realize a lighting device of small light distribution angle and less leakage light and further to realize a lighting device in which the light beam is easy to control. The following is an example of the structure to meet the above purpose. A lighting device including: a light guide; LEDs set at a side surface of the light guide; a prism sheet set on a major surface of the light guide, in which a first louver which extends in a first direction and, a second louver which extends in an orthogonal direction to the first direction are superposed on the prism sheet.

The purpose of the present invention is to realize a lighting device which can be switched between an overall lighting and a local lighting with a single lighting device. The concrete structure is a lighting device including: a first light guide having a first major surface and a first back surface, and a first hole; a second light guide, disposed on the first light guide, and having a second major surface, a second back surface, and a second hole; a reflection sheet disposed under the first back surface of the first light guide; a liquid crystal lens disposed above the second major surface of the second light guide, in which first LEDs and second LEDs are disposed circumferentially along a side wall of the first hole and a side wall of the second hole, respectively, and the first LEDs and the second LEDs are displaced each other in azimuth direction.

Growing community of inventors

Tokyo, Japan

Masafumi Okada