# US 9,435,513 B2 · Light source device having optical members for changing one or more characteristics of excitation light from an excitation light source > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,435,513 B2 - Document ID: US9435513B2 - Status: Granted - Kind: B2 - Application number: 14/247,705 - Filed: 2014-04-08 - Published: 2014-08-07 - Granted: 2016-09-06 - Earliest claimed: 2011-10-11 - Assignees: Olympus Corporation - Applicants: Olympus Corporation - Inventors: Kazuaki Tamura; Eiji Yamamoto; Takeshi Ito - Web page: https://patentgrep.com/patent/US9435513B2 ## CPC - G02B 6/0008: {the light being emitted at the end of the fibre} - F21V 5/10: comprising photoluminescent material - F21V 9/40: with provision for controlling spectral properties, e.g. colour, or intensity - F21V 13/08: the elements being filters or photoluminescent elements and reflectors - A61B 1/0638: {providing two or more wavelengths} - A61B 1/0653: {with wavelength conversion} - F21Y 2115/10: Light-emitting diodes [LED] - F21Y 2115/30: Semiconductor lasers - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - 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 A light source device includes a first excitation light source which emits first excitation light having a wavelength in a first wavelength region, a first optical member, a second optical member and a holding member which holds the first optical member and the second optical member. The first optical member converts at least part of the first excitation light to emit first wavelength converted light, and increase divergence angle of the transmitted first excitation light by a first incremental angle. A second optical member is disposed in a region including an optical axis of the first excitation light, and increases the divergence angle of the transmitted first excitation light by a second incremental angle larger than the first incremental angle. ## Claims ### Claim 1 A light source device comprising: a first excitation light source configured to emit first excitation light having a wavelength in a first wavelength region; a first optical member configured to absorb at least part of the first excitation light, convert a wavelength of the part of the first excitation light to emit first wavelength converted light, and increase a divergence angle of transmitted first excitation light by a first incremental angle; a second optical member configured to increase the divergence angle of the transmitted first excitation light by a second incremental angle larger than the first incremental angle; and a holding member which holds the first optical member and the second optical member, wherein the second optical member includes a powder material and a transparent member which transmits light, an absorption rate of the first excitation light of the powder material is less than a predetermined value, and the powder material is dispersed in the transparent member. ### Claim 2 (depends on 1) The light source device according to claim 1, wherein the first optical member includes a transparent fluorescent material, and the powder material absorbs light having a wavelength in a second wavelength region different from the first wavelength region, and converts the wavelength of the light having the wavelength in the second wavelength region to emit second wavelength converted light. ### Claim 3 (depends on 2) The light source device according to claim 2, further comprising an optical fiber configured to guide the first excitation light, wherein the holding member comprises an incidence portion through which the first excitation light guided by the optical fiber enters, and an emission portion which emits at least part of the first excitation light and the first wavelength converted light, both the first optical member and the second optical member are disposed on an optical axis of the first excitation light entering through the incidence portion, and the first optical member is located closer to the incidence portion than the second optical member. ### Claim 4 (depends on 3) The light source device according to claim 3, wherein a wavelength of the second wavelength converted light is shorter than a wavelength of the first wavelength converted light. ### Claim 5 (depends on 3) The light source device according to claim 3, wherein the thickness of the second optical member in an optical axis direction increases towards the optical axis. ### Claim 6 (depends on 3) The light source device according to claim 3, wherein the first optical member and the second optical member are columnar, a diameter of the second optical member is larger than a diameter of the first optical member, and a thickness of the second optical member in an optical axis direction is greater than a thickness of the first optical member in the optical axis direction. ### Claim 7 (depends on 2) The light source device according to claim 2, wherein the holding member comprises an incidence portion through which the first excitation light enters, and an emission portion which emits the first wavelength converted light, and the first optical member and the second optical member are arranged to divide a surface perpendicular to an optical axis of the first excitation light which enters through the incidence portion. ### Claim 8 (depends on 7) The light source device according to claim 7, wherein the second optical member is disposed on the optical axis of the first excitation light and the first optical member is not disposed on the optical axis of the first excitation light. ### Claim 9 (depends on 8) The light source device according to claim 8, wherein a surface of the second optical member through which the first excitation light enters is larger than a beam spot diameter of the first excitation light in the surface. ### Claim 10 (depends on 2) The light source device according to claim 2, further comprising a second excitation light source configured to emit second excitation light having a wavelength in the second wavelength region, wherein the second optical member is configured to absorb at least part of the second excitation light, and convert the wavelength of the second excitation light to emit the second wavelength converted light. ### Claim 11 (depends on 10) The light source device according to claim 10, wherein the first excitation light and the second excitation light are combined by an optical coupler, the holding member comprises an incidence portion through which the first excitation light and the second excitation light that have been combined enter, and an emission portion which emits the first excitation light, the second excitation light, the first wavelength converted light, and the second wavelength converted light, and an optical axis of the first excitation light entering through the incidence portion corresponds to an optical axis of the second excitation light. ### Claim 12 (depends on 11) The light source device according to claim 11, wherein at least one of the first excitation light and the second excitation light pass through the first optical member and the second optical member, and are then emitted from the emission portion, and the divergence angle of the first excitation light or the second excitation light, the divergence angle of the first wavelength converted light, and the divergence angle of the second wavelength converted light emitted from the emission portion are adjusted to be equal to one another. ### Claim 13 (depends on 2) The light source device according to claim 2, wherein the first optical member includes a single crystal or polycrystalline fluorescent material. ### Claim 14 (depends on 1) The light source device according to claim 1, wherein the first optical member also absorbs part of light having a wavelength in a second wavelength region different from the first wavelength region, and converts the wavelength of the part of the light having the wavelength in the second wavelength region to emit the first wavelength converted light, the second optical member includes a powder fluorescent material and a transparent member which transmits light, the powder fluorescent material absorbing the light having the wavelength in the second wavelength region and converting the wavelength of the light having the wavelength in the second wavelength region to emit second wavelength converted light, and the powder fluorescent material is dispersed in the transparent member. ### Claim 15 (depends on 1) The light source device according to claim 1, wherein the powder material includes diffused particles, and the transparent member transmits the first excitation light and the first wavelength converted light, the diffused particles includes one of reflective diffused particles which reflect at least one of the first excitation light and the first wavelength converted light, and transmissive diffused particles which have a refractive index higher than a refractive index of the transparent member and transmit at least one of the first excitation light and the first wavelength converted light. ### Claim 16 (depends on 1) The light source device according to claim 1, wherein the first excitation light passes through the first optical member and the second optical member, and are then emitted from an emission portion, and a diffusion characteristic of the second optical member is determined based on the divergence angle of the first excitation light and the divergence angle of the first wavelength converted light emitted from the emission portion. ### Claim 17 (depends on 1) The light source device according to claim 1, wherein the first excitation light passes through the first optical member and the second optical member, and are then emitted from an emission portion, and the divergence angle of the first excitation light, and the divergence angle of the first wavelength converted light emitted from the emission portion are adjusted to be substantially equal to one another. ### Claim 18 (depends on 1) The light source device according to claim 1, wherein the second optical member hardly absorbs the first excitation light. ### Claim 19 (depends on 1) The light source device according to claim 1, wherein the second optical member is disposed in a region including at least an area which includes an optical axis of the first excitation light, light intensity regarding the first excitation light in the area being equal to or more than 1/e times light intensity on the optical axis, where e is Napier's constant. ### Claim 20 A light source device comprising: a first excitation light source configured to emit first excitation light having a wavelength in a first wavelength region; a first optical member configured to absorb at least part of the first excitation light, convert a wavelength of the part of the first excitation light to emit first wavelength converted light, and increase a divergence angle of transmitted first excitation light by a first incremental angle; a second optical member configured to increase the divergence angle of the transmitted first excitation light by a second incremental angle larger than the first incremental angle; and a holding member which holds the first optical member and the second optical member, wherein the holding member comprises an incidence portion through which the first excitation light enters, and an emission portion which emits the first wavelength converted light, the first optical member and the second optical member are arranged to divide a surface perpendicular to an optical axis of the first excitation light which enters through the incidence portion, and the second optical member is disposed on the optical axis of the first excitation light and the first optical member is not disposed on the optical axis of the first excitation light. ### Claim 21 A light source device comprising: a first excitation light source configured to emit first excitation light having a wavelength in a first wavelength region; a first optical member configured to absorb at least part of the first excitation light, convert a wavelength of the part of the first excitation light to emit first wavelength converted light, and increase a divergence angle of transmitted first excitation light by a first incremental angle; a second optical member configured to increase the divergence angle of the transmitted first excitation light by a second incremental angle larger than the first incremental angle; a holding member which holds the first optical member and the second optical member; and a second excitation light source configured to emit second excitation light having a wavelength in a second wavelength region, wherein the second optical member is configured to absorb at least part of the second excitation light, and convert the wavelength of the second excitation light to emit the second wavelength converted light, the first excitation light and the second excitation light are combined by an optical coupler, the holding member comprises an incidence portion through which the first excitation light and the second excitation light that have been combined enter, and an emission portion which emits the first excitation light, the second excitation light, the first wavelength converted light, and the second wavelength converted light, and an optical axis of the first excitation light entering through the incidence portion corresponds to an optical axis of the second excitation light.