Ring-shaped light-conducting apparatus with uniform luminance

Patent metadata

Field	Value
Publication number	US-9618676-B2
Application number	US-201314435215-A
Country	US
Kind code	B2
Filing date	Oct 10, 2013
Priority date	Oct 15, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A light-conducting apparatus includes a light source, a light-conducting member and a light-reflecting structure. The light-conducting member includes a ring-shaped portion, a light-receiving surface and a radially outwardly bulged portion. The ring-shaped portion extends continuously over an entire circumference of the ring-shaped portion in a circumferential direction of the ring-shaped portion. The light-receiving surface causes light from the light source to enter the light-conducting member through the light-receiving surface. The radially outwardly bulged portion is bulged radially outwardly from the ring-shaped portion and causes the light having entered the light-conducting member through the light-receiving surface to enter the ring-shaped portion in one direction in the circumferential direction of the ring-shaped portion. The light-reflecting structure reflects a portion of the light having entered the light-conducting member through the light-receiving surface and causes the reflected light to enter the ring-shaped portion in a direction opposite to the one direction in the circumferential direction of the ring-shaped portion.

First claim

The invention claimed is:

1. A light-conducting apparatus comprising:
a light source,
a light-conducting member, and
a light-reflecting structure,
wherein the light-conducting member includes a ring-shaped portion, a light-receiving surface and a radially outwardly bulged portion,
wherein the ring-shaped portion extends continuously over an entire circumference of the ring-shaped portion in a circumferential direction of the ring-shaped portion,
wherein the light-receiving surface causes light from the light source to enter the light-conducting member through the light-receiving surface,
wherein the radially outwardly bulged portion protrudes in a radial direction beyond the circumference of the ring-shaped portion outwardly from the ring-shaped portion such that the light-receiving surface is provided in a radial direction beyond the circumference of the ring-shaped portion outwardly away from the ring-shaped portion and the light having entered the light-conducting member through the light-receiving surface enters the ring-shaped portion in one direction in the circumferential direction of the ring-shaped portion, and
wherein the light-reflecting structure reflects a portion of the light having entered the light-conducting member through the light-receiving surface and causes the reflected light to enter the ring-shaped portion in a direction opposite to the one direction in the circumferential direction of the ring-shaped portion.

2. A light-conducting apparatus according to claim 1 ,
wherein the light-reflecting structure includes a layer provided at the radially outwardly bulged portion and a boundary surface located between the light-conducting member and the layer, a refractive index of the layer being different from a refractive index of the light-conducting member, and
wherein the portion of the light having entered the light-conducting member through the light-receiving surface is reflected at the boundary surface.

3. A light-conducting apparatus according to claim 2 , wherein a medium of the layer is air.

4. A light-conducting apparatus according to claim 3 , wherein the layer is a notch concave from a surface of the radially outwardly bulged portion.

5. A light-conducting apparatus according to claim 2 , wherein an entirety of the light having entered the light-conducting member through the light-receiving surface and traveling to the boundary surface is reflected at the boundary surface.

6. A light-conducting apparatus according to claim 2 , wherein a portion of the light having entered the light-conducting member through the light-receiving surface and traveling to the boundary surface is reflected at the boundary surface and a remainder of the light is refracted at the boundary surface to enter the layer.

7. A light-conducting apparatus according to claim 1 , wherein the radially outwardly bulged portion protrudes radially outwardly from the ring-shaped portion such that the light having entered the light-conducting member through the light-receiving surface enters the ring-shaped portion in the one, tangential direction in the circumferential direction of the ring-shaped portion, and
wherein the light-reflecting structure reflects the one portion, not an entirety of the light having entered the light-conducting member through the light-receiving surface and causes the reflected light to enter the ring-shaped portion in the direction tangential and opposite to the one, tangential direction in the circumferential direction of the ring-shaped portion.

Assignees

• Kojima Ind Corp

Inventors

• Sakanashi Katsutoshi
• Une Tomoya
• Kandori Hirokazu

Classifications

• B60Q3/0243

  Operations & Transport · mapped topic

• B60Q3/004

  Operations & Transport · mapped topic

• G02B6/0045

  by shaping at least a portion of the light guide · CPC title

• B60K37/02

  Operations & Transport · mapped topic

• G02B6/001

  the light being emitted along at least a portion of the lateral surface of the fibre · CPC title