# US 10,480,721 B2 · Light flux controlling member, light emitting device and illuminating device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,480,721 B2
- Document ID: US10480721B2
- Status: Granted
- Kind: B2
- Application number: 15/579,259
- Filed: 2016-06-01
- Published: 2018-06-07
- Granted: 2019-11-19
- Earliest claimed: 2015-06-03
- Assignees: Enplas Corporation
- Applicants: Enplas Corporation
- Inventors: Akinobu Seki
- Web page: https://patentgrep.com/patent/US10480721B2

## CPC

- F21K 9/232: specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
- F21K 9/69: Details of refractors forming part of the light source
- F21V 5/00: Refractors for light sources (characterised by cooling arrangements F21V29/504)
- F21V 5/043: {the lens having cylindrical faces, e.g. rod lenses, toric lenses}
- F21V 5/045: {the lens having discontinuous faces, e.g. Fresnel lenses}
- F21V 7/0091: {using total internal reflection}
- G02B 5/02: Diffusing elements; Afocal elements
- G02B 19/0014: {at least one surface having optical power}
- G02B 19/0028: {refractive and reflective surfaces, e.g. non-imaging catadioptric systems}
- G02B 19/0061: {the light source comprising a LED}
- F21K 9/68: Details of reflectors forming part of the light source
- F21Y 2103/33: annular
- F21Y 2105/16: square or rectangular, e.g. for light panels
- F21Y 2115/10: Light-emitting diodes [LED]
- F21K: NON-ELECTRIC LIGHT SOURCES USING LUMINESCENCE; LIGHT SOURCES USING ELECTROCHEMILUMINESCENCE; LIGHT SOURCES USING CHARGES OF COMBUSTIBLE MATERIAL; LIGHT SOURCES USING SEMICONDUCTOR DEVICES AS LIGHT-GENERATING ELEMENTS; LIGHT SOURCES NOT OTHERWISE PROVIDED FOR
- F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
- G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- F21Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED

## Abstract

This luminous flux control member has an entry region, a first fully reflective surface, an exit surface, a second fully reflective surface, a third fully reflective surface, and a connection surface. Some of the light emitted by the light-emission element enters via the entry region, subsequently reflects off the first fully reflective surface, and exits from the exit surface. The remainder of the light emitted by the light-emission element enters via the entry region, reflects off the second fully reflective surface and the third fully reflective surface in the stated order, exits from the connection surface, enters again via the first fully reflective surface, and subsequently exits from the exit surface.

## Claims

### Claim 1

A light flux controlling member configured to control a distribution of light emitted from a light-emitting element, the light flux controlling member comprising:
an incidence region configured to face the light-emitting element;
a first total reflection surface disposed on a side opposite to the incidence region;
an emission surface disposed in one direction orthogonal to an optical axis of the light-emitting element;
a second total reflection surface disposed on a side opposite to the emission surface in the one direction;
a third total reflection surface disposed on a side opposite to the second total reflection surface in a direction along the optical axis; and
a connection surface connecting the first total reflection surface and the third total reflection surface, wherein
a part of the light emitted from the light-emitting element enters the light flux controlling member from the incidence region so as to be reflected by the first total reflection surface before being emitted from the emission surface, and
another part of the light emitted from the light-emitting element enters the light flux controlling member from the incidence region so as to be reflected by the second total reflection surface and the third total reflection surface in this order, and thereafter emitted from the connection surface so as to re-enter the light flux controlling member from the first total reflection surface before being emitted from the emission surface.

### Claim 2 (depends on 1)

The light flux controlling member according to claim 1, wherein the incidence region includes:
a first incidence surface configured to face the light-emitting element, the first incidence surface being configured to allow incidence of the light emitted from the light-emitting element such that at least light emitted from the light-emitting element with a small emission angle to the optical axis is allowed to be incident on the first incidence surface; and
a second incidence surface disposed on the second total reflection surface side relative to the first incidence surface in the one direction, the second incidence surface being configured to allow incidence of light emitted from the light-emitting element toward the second total reflection surface side.

### Claim 3 (depends on 2)

The light flux controlling member according to claim 2, wherein the second incidence surface is disposed along the optical axis.

### Claim 4 (depends on 2)

The light flux controlling member according to claim 2, wherein the first incidence surface includes:
a first protrusion disposed between the optical axis and the emission surface, the first protrusion being configured to allow incidence of a part of light emitted from the light-emitting element toward the emission surface, and then reflect, toward the first total reflection surface, the part of light emitted from the light-emitting element toward the emission surface; and
a second protrusion disposed on the second incidence surface side relative to the first protrusion in the one direction, the second protrusion being configured to mainly allow incidence of a part of light emitted from an end portion of the light-emitting element on the emission surface side, and then reflect, toward the first total reflection surface, the part of light emitted from the end portion of the light-emitting element on the emission surface side.

### Claim 5 (depends on 1)

The light flux controlling member according to claim 1, wherein:
the first total reflection surface is formed such that an inclination of a tangent thereto gradually decreases toward the emission surface;
the second total reflection surface is formed such that as a distance of the second total reflection surface from the third total reflection surface decreases, a distance of the second total reflection surface from the emission surface increases; and
the third total reflection surface is formed such that as a distance of the third total reflection surface from the second total reflection surface decreases, a distance of the third total reflection surface from the emission surface increases.

### Claim 6 (depends on 1)

The light flux controlling member according to claim 1, wherein the connection surface and the emission surface are disposed in the direction along the optical axis.

### Claim 7 (depends on 1)

The light flux controlling member according to claim 1, wherein the incidence region, the first total reflection surface, the emission surface, the second total reflection surface, the third total reflection surface and the connection surface are rotationally symmetrical about a rotation axis extending along the optical axis, the rotation axis being disposed on the second total reflection surface side and the third total reflection surface side relative to the optical axis at a position distanced from the optical axis in comparison with the second total reflection surface and the third total reflection surface.

### Claim 8 (depends on 1)

The light flux controlling member according to claim 1, wherein the incidence region, the first total reflection surface, the emission surface, the second total reflection surface, the third total reflection surface and the connection surface extend in a direction orthogonal to the optical axis and the one direction.

### Claim 9 (depends on 1)

A light-emitting device comprising:
a plurality of light-emitting elements; and
the light flux controlling member according to claim 1, wherein
the light flux controlling member is disposed such that the incidence region faces the plurality of light-emitting elements.

### Claim 10 (depends on 9)

An illumination apparatus comprising:
the light-emitting device according to claim 9; and
a cover configured to allow light emitted from the light-emitting device to pass therethrough while diffusing the light.