# US 9,519,207 B2 · Wavelength converting device and light emitting device using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,519,207 B2 - Document ID: US9519207B2 - Status: Granted - Kind: B2 - Application number: 13/726,785 - Filed: 2012-12-26 - Published: 2013-06-27 - Granted: 2016-12-13 - Earliest claimed: 2011-12-27 - Assignees: Nichia Corporation - Applicants: Nichia Corporation - Inventors: Yoshitaka Nakatsu; Takafumi Sugiyama - Web page: https://patentgrep.com/patent/US9519207B2 ## CPC - C04B 35/44: based on aluminates - C04B 35/6303: {Inorganic additives} - C09K 11/02: Use of particular materials as binders, particle coatings or suspension media therefor - C09K 11/7774: {Aluminates} - F21V 9/32: characterised by the arrangement of the photoluminescent material - F21V 9/45: by adjustment of photoluminescent elements - F21V 13/14: the elements being filters or photoluminescent elements, reflectors and refractors - G03B 21/204: {using secondary light emission, e.g. luminescence or fluorescence (using different colours G03B33/00; if related to video signals H04N9/3197)} - G03B 33/06: by additive-colour projection apparatus - H04N 9/3161: {using laser light sources (using laser beams scanning the display screen H04N9/3129)} - C04B 2235/3215: Barium oxides or oxide-forming salts thereof - C04B 2235/3222: Aluminates other than alumino-silicates, e.g. spinel (MgAl2O4) - C04B 2235/3224: Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide - C04B 2235/3229: Cerium oxides or oxide-forming salts thereof - C04B 2235/3284: Zinc oxides, zincates, cadmium oxides, cadmiates, mercury oxides, mercurates or oxide forming salts thereof - C04B 2235/445: Fluoride containing anions, e.g. fluosilicate - C04B 2235/5436: micrometer sized, i.e. from 1 to 100 micron - C04B 2235/6582: Hydrogen containing atmosphere - C04B 2235/666: Applying a current during sintering, e.g. plasma sintering [SPS], electrical resistance heating or pulse electric current sintering [PECS] - C04B 2235/764: Garnet structure A3B2(CO4)3 - C04B 2235/945: Products containing grooves, cuts, recesses or protusions - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Provided is a wavelength converting device having excellent optical output. The wavelength converting device includes a substrate and a wavelength converting member disposed on the substrate. The wavelength converting member includes a fluorescent material powder and a binder binding the fluorescent material powder. An upper surface of the wavelength converting member serves as a light emitting surface which includes upper surfaces of the fluorescent material powder and an upper surface of the binder. The binder has first recesses formed adjacent to the fluorescent material powder in the upper surface of the binder. ## Claims ### Claim 1 A wavelength converting device comprising: a substrate; and a wavelength converting member disposed on the substrate; wherein the wavelength converting member comprises a fluorescent material powder and a binder binding the fluorescent material powder, wherein an upper surface of the wavelength converting member is a light emitting surface comprising upper surfaces of the fluorescent material powder and an upper surface of the binder, wherein the binder has a first recess formed adjacent to the fluorescent material powder in the upper surface of the binder, wherein the upper surfaces of the fluorescent material powder are protruded from the upper surface of the binder such that a second recess is formed between the fluorescent material powder, the second recess having a bottom surface that is the upper surface of the binder, and wherein the first recess is formed in the bottom surface of the second recess. ### Claim 2 (depends on 1) The wavelength converting device according to claim 1, wherein the upper surfaces of the fluorescent material powder and the upper surface of the binder are respectively flat and in parallel with each other. ### Claim 3 (depends on 1) The wavelength converting device according to claim 1, further comprising a non-reflecting coating disposed on the upper surface of the wavelength converting member. ### Claim 4 (depends on 1) The wavelength converting device according to claim 1, wherein the upper surface of the wavelength converting member is a light emitting surface and also an incident surface where light for exciting the fluorescent material powder enters. ### Claim 5 (depends on 1) The wavelength converting device according to claim 1, further comprising a reflecting member interposed between the wavelength converting member and the substrate. ### Claim 6 (depends on 1) The wavelength converting device according to claim 1, wherein the substrate is a ceramic substrate or a metallic substrate. ### Claim 7 (depends on 1) A light emitting device comprising the wavelength converting device according to claim 1, and a light source for exciting the fluorescent material powder of the wavelength converting device. ### Claim 8 (depends on 7) The light emitting device according to claim 7, wherein the light source has a emission peak in a range of 440 to 480 nm and the fluorescent material powder has a emission peak in a range of 500 to 540 nm. ### Claim 9 A method of manufacturing a wavelength converting device, the method comprising: preparing a fluorescent material powder by preparing a mixture of raw material powders and a sintering aid agent, and sintering the mixture; preparing a wavelength converting member by preparing a mixture of the fluorescent material powder and a material of a binder configured to bind the fluorescent material powder, and sintering the mixture; etching an upper surface of the wavelength converting member by using an etching solution having a higher etch rate to the sintering aid agent than to the fluorescent material powder and the binder such that (i) the binder has a first recess formed adjacent to the fluorescent material powder in an upper surface of the binder, and (ii) upper surfaces of the fluorescent material powder protrude from the upper surface of the binder such that a second recess is formed between the fluorescent material powder, the second recess having a bottom surface which is the upper surface of the binder, wherein the first recess is formed in the bottom surface of the second recess; and mounting the wavelength converting member on a substrate. ### Claim 10 (depends on 9) The method of manufacturing a wavelength converting device according to claim 9, wherein the etching comprises performing a chemical mechanical polishing process on the upper surface of the wavelength converting member. ### Claim 11 (depends on 1) The wavelength converting device according to claim 1, wherein a thickness of the wavelength converting member is in a range of 50 to 500 μm. ### Claim 12 (depends on 1) The wavelength converting device according to claim 1, wherein the fluorescent material powder comprises a powder made of one selected from a group of Lu3Al5O12:Ce, Y3Al5O12:Ce, and Y2.5Gd0.5Al2.5Ga2.5O12:Ce. ### Claim 13 (depends on 1) The wavelength converting device according to claim 1, wherein the binder is made of an inorganic material. ### Claim 14 (depends on 1) The wavelength converting device according to claim 1, wherein the binder is made of one selected from a group of Al2O3, MgO, ZrO2, BaO, Lu2O3, TiO2, Cr2O3, WO3, V2O5, MoO3, SrO, Na2O, Y2O3, SiO2, B2O3, P2O5, PbO, N2O, K2O, and CaO. ### Claim 15 (depends on 1) The wavelength converting device according to claim 1, wherein the fluorescent material powder and the binder contain an element common to the fluorescent material powder and the binder. ### Claim 16 (depends on 7) A projector comprising the light emitting device according to claim 7. ### Claim 17 (depends on 9) The method according to claim 9, wherein the fluorescent material powder is made of one selected from a group of Lu3Al5O12:Ce, Y3Al5O12:Ce, and Y2.5Gd0.5Al2.5Ga2.5O12:Ce and, wherein the binder is made of one selected from a group of Al2O3 and BaF2. ### Claim 18 (depends on 9) The method according to claim 9, comprising a polishing process and a chemical mechanical polishing process performed after the polishing process, wherein a damaged layer near the upper surface resulting from the polishing process is removed in the chemical mechanical polishing process.