Illumination apparatus

Patent metadata

Field	Value
Publication number	US-2018100627-A1
Application number	US-201715835530-A
Country	US
Kind code	A1
Filing date	Dec 8, 2017
Priority date	Jun 10, 2015
Publication date	Apr 12, 2018
Grant date	—

Abstract

An illumination apparatus includes a first wavelength converter which absorbs part of the first excitation light and emits first wavelength-converted light, a second wavelength converter which absorbs part of the first excitation light and emits second wavelength-converted light, a reflector including a reflecting surface which is arranged to surround the members, and a holder which holds the members. A first region where light distribution angles of light emitted from the members have a predetermined value or less and a second region where the light distribution angle is less than the predetermined value are present in a region surrounded by the reflecting surface. The holder holds at least one part of the wavelength converter and at least one part of the second wavelength converter at the first region.

First claim

What is claimed is:

1 . An illumination apparatus comprising: a second wavelength converter which absorbs part of the first excitation light and emits second wavelength-converted light that is light whose wavelength differs from a wavelength of the first excitation light and the first wavelength-converted light;
a reflector including a reflecting surface which is arranged to surround the first wavelength converter and the second wavelength converter, the reflector reflecting the first wavelength-converted light and the second wavelength-converted light on the reflecting surface thereof; and a holder which holds the first wavelength converter and the second wavelength converter, wherein the illumination apparatus emits a first illumination light including the first wavelength conversion light and the second wavelength conversion light reflected on the reflector, wherein a first region where light distribution angles of light emitted from each of the first wavelength converter and the second converter have a predetermined value or less and a second region where the light distribution angle is less than the predetermined value are present in a region surrounded by the reflecting surface, wherein the holder holds at least one part of the first wavelength converter and at least one part of the second wavelength converter at the first region.

2 . The illumination apparatus according to claim 1 , wherein the first wavelength converter, the second wavelength converter, the holder and the reflector constitutes a wavelength conversion unit,
wherein light distribution angles of light emitted from each of the first wavelength converter and the second converter are substantially equal in the first region, wherein the holder holds the first wavelength converter and the second wavelength converter such that both a substantial light emission point of the first wavelength converter and a substantial light emission point of the second wavelength converter are in the first region, wherein the wavelength conversion unit emits the first illumination light.

3 . The illumination apparatus according to claim 2 ,
wherein the holder including: a holder incidence portion which the first excitation light enters; a holder emission portion which emits the first wavelength-converted light and the second wavelength-converted light; and a through hole which extends from the holder incidence portion to the holder emission portion, wherein: the reflector is formed an inner surface of the through hole; the through hole and the reflecting surface are tapered such that a diameter thereof increases from the holder incidence portion to the holder emission portion; an inclination angle formed by the inner surface on which the reflector is formed and the central axis of the through hole is defined as a taper angle; and when an inclination angle formed by the central axis and a line connecting the substantial light emission point position of the first wavelength converter and a point on an open end of the holder emission portion is defined as a direct emission limit angle of the first wavelength-converted light, and an inclination angle formed by the central axis and a line connecting the substantial light emission point position of the second wavelength converter and a point on the open end of the holder emission portion is defined as a direct emission limit angle of the second wavelength-converted light, the first region is an incidence portion side first region that is present closer to the holder incidence portion than the holder emission portion, the direct emission limit angle of the first wavelength-converted light and the direct emission limit angle of the second wavelength-converted light are equal to or less than twice the taper angle in the incidence portion side first region.

4 . The illumination apparatus according to claim 3 ,
wherein the wavelength conversion unit includes a diffusion member held on the central axis in the through hole, and the diffusion member converts the first excitation light into first excitation light diffused light whose light distribution angle is increased, without changing a wavelength of the first excitation light; and when an intersection of an incident surface of the diffusion member and the central axis is defined as a substantial diffusion point of the diffusion member, the substantial diffusion point of the diffusion member is set in the incidence portion side first region.

5 . The illumination apparatus according to claim 2 ,
wherein the holder including: a holder incidence portion which the first excitation light enters; a holder emission portion which emits the first wavelength-converted light and the second wavelength-converted light; and a through hole which extends from the holder incidence portion to the holder emission portion, wherein: the reflector is formed an inner surface of the through hole; the through hole and the reflecting surface are tapered such that a diameter thereof increases from the holder incidence portion to the holder emission portion; an inclination angle formed by the inner surface on which the reflector is formed and the central axis of the through hole is defined as a taper angle; and when an inclination angle formed by the central axis and a line connecting the substantial light emission point position of the first wavelength converter and a point on an open end of the holder emission portion is defined as a direct emission limit angle of the first wavelength-converted light, and an inclination angle formed by the central axis and a line connecting the substantial light emission point position of the second wavelength converter and a point on the open end of the holder emission portion is defined as a direct emission limit angle of the second wavelength-converted light, the first region is an emission portion side first region that is present closer to the holder emission portion than the holder incidence portion, the direct emission limit angle of the first wavelength-converted light and the direct emission limit angle of the second wavelength-converted light are equal to or more than three times the taper angle in the emission portion side first region.

6 . The illumination apparatus according to claim 5 ,
wherein the wavelength conversion unit includes a diffusion member held on the central axis in the through hole, and the diffusion member converts the first excitation light into first excitation light diffused light whose light distribution angle is increased, without changing a wavelength of the first excitation light; and when an intersection of an incident surface of the diffusion member and the central axis is defined as a substantial diffusion point of the diffusion member, the substantial diffusion point of the diffusion member is set in the emission portion side first region.

7 . The illumination apparatus according to claim 4 , wherein the diffusion member increases a light distribution angle of the first excitation light diffused light between a maximum angle and a minimum angle of emission angles of the first wavelength-converted light and the second wavelength-converted light emitted from the holder emission portion, a first wavelength conversion light distribution angle that is an angle at which the first wavelength-converted light is emitted from the first wavelength converter, and a second wavelength conversion light distribution angle that is an angle at which the second wavelength-converted light is emitted from the second wavelength converter.

8 . The illumination apparatus according to claim 4 ,
wherein the diffusion member increases a light distribution angle of the first excitation light diffused light emitted from the holder emission portion between

Assignees

• Olympus Corp

Inventors

• Tamura Kazuaki
• Nishio Masahiro
• Ohara Satoshi

Classifications

• A61B1/0653 Primary

  with wavelength conversion · CPC title

• A61B1/07

  using light-conductive means, e.g. optical fibres · CPC title

• F21V7/04

  Optical design · CPC title

• F21Y2115/30

  Semiconductor lasers · CPC title

• G02B23/2469

  using optical fibres · CPC title