Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Hiroyuki Sekii

Kyohei Nakamura

Osamu Tanahashi

Kenichiro Tanaka

Hideharu Kawachi

Tadashi Murakami

Yoko Matsubayashi

Shinichi Anami

Toshizumi Okada

A light guide includes a front surface. A back surface is opposite the front surface and includes a depression. A light incident surface introduces light. The light reflects off the depression and is emitted through the front surface. The depression includes an inclined side surface that faces the light incident surface. The inclined side surface includes a reflective curved surface that includes at least 50% of a surface area of the inclined side surface. In a cross section view of the depression in a plane substantially orthogonal to the front surface, a first tangent that touches a curved line defining the reflective curved surface of the inclined side surface and a second tangent that touches the curved line in a different location than the first tangent form a first angle that is greater than or equal to 0&#xb0; and less than or equal to 30&#xb0;.

Light guide and lighting apparatus including the same

An illumination device includes a light source unit and a light guide plate configured to guide light coming from the light source unit. The light guide plate includes an incidence surface, main emission surfaces from which the light incident on the incidence surface is emitted, and an end emission surface which is opposed to the incidence surface and from which the light is emitted. At least one of the main emission surfaces has a stepped surface which is formed such that the thickness of the light guide plate becomes thinner at a side of the end emission surface than at a side of the incidence surface. The stepped surface is configured to reflect the light in a direction opposite to a light guide direction extending from the incidence surface toward the end emission surface and inclined with respect to the light guide direction.

Illumination device with at least one main emission surface having a stepped surface configured to reflect light in multiple directions

A luminaire is provided. A main surface of a light-guiding panel included in the luminaire includes a reflecting area having a plurality of approximately conical recesses. An angle &#x3b8; formed by a lateral surface of each of the recesses and the main surface of the light-guiding panel satisfies a condition defined by a distance D from a center position of a light source to a center position of the reflecting area, a distance H from an illumination target surface to the center position of the light source, an angle &#x3b3; which the light-guiding panel forms with a horizontal plane, a refractive index n of the light-guiding panel, and a surface roughness Rof the lateral surface of each of the recesses.

Luminaire

In a lens-mounted light emitting unit comprising LED elements of multiple light colors, narrow-angle light distribution is enabled, and color mixing properties are improved. The lens-mounted light emitting unit comprises LED elements of multiple light colors placed on a base plate, and a lens unit having a shape of a body of revolution to color-mix and emit the light from the LED elements. Assuming an arbitrary contact point between the side incident surface and the upper incident surface of the lens unit, and that light from an LED element farthest from the contact point is refracted at the contact point to form a light path intersecting the emitting surface at an intersection point, the emitting surface inside a circle formed by continuously connecting such intersection points has a diffusion angle larger than the diffusion angle of the emitting surface outside the circle. This enables narrow-angle light distribution, and makes it possible to improve color mixing properties.

Lens-mounted light emitting unit

An optical member for refracting light emitted from a light source and projecting the light from a light projecting surface thereof includes a plurality of concave or convex portions formed on the light projecting surface. The concave or convex portions are concentrically arranged on a plurality of circles having a common center point. The concave or convex portions on the circles adjoining to each other are arranged in different phase positions with respect to radial lines extending from the center point.

Optical member and illumination apparatus using same

An illumination device includes a plurality of light sources for emitting light and an optical member arranged in front of the light sources to control distribution of the light emitted from the light sources. The optical member includes a plurality of lens portions having storage recess portions formed in alignment with the light sources to accommodate the light sources and a plurality of ribs extending laterally from the lens portions to fix the lens portions to a substrate holding the light sources, each of the lens portions having a light distribution control portion formed in a rear opening edge of each of the storage recess portions to distribute frontward the light emitted from the light sources toward the ribs.

Growing community of inventors

Osaka, Japan

Hiroyuki Sekii