# US 2021/0280752 A1 · Wavelength conversion wheel and projection device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0280752 A1 - Document ID: US20210280752A1 - Status: Published application - Kind: A1 - Application number: 17/195,644 - Filed: 2021-03-09 - Published: 2021-09-09 - Earliest claimed: 2020-03-09 - Assignees: Coretronic Corporation - Applicants: Coretronic Corporation - Inventors: CHIH-MING CHEN - Web page: https://patentgrep.com/patent/US20210280752A1 ## CPC - H10H 20/8515: {not being in contact with the bodies} - G02B 26/008: {in the form of devices for effecting sequential colour changes, e.g. colour wheels} - G03B 21/16: Cooling; Preventing overheating - G03B 21/204: {using secondary light emission, e.g. luminescence or fluorescence (using different colours G03B33/00; if related to video signals H04N9/3197)} - H10H 20/8512: {Wavelength conversion materials} - H10H 20/8514: {characterised by their shape, e.g. plate or foil} - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - 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) ## Abstract A wavelength conversion wheel includes a turntable, a wavelength conversion layer, a pressure ring, an anodized layer and a balance weight. The turntable has an inner ring portion and a ring-shaped irradiation portion. The ring-shaped irradiation portion is connected to an outer edge of the inner ring portion. The ring-shaped irradiation portion includes a wavelength conversion region. The wavelength conversion layer is disposed on the wavelength conversion region. The pressure ring presses against the inner ring portion and has a first surface facing away the turntable. The anodized layer is disposed on the first surface. The balance weight is disposed on the anodized layer, wherein the surface roughness of the anodized layer is 1 μm to 10 μm. The wavelength conversion wheel of the invention has better reliability. A projection device with the wavelength conversion wheel is further provided. ## Claims ### Claim 1 A wavelength conversion wheel, comprising: a turntable, having an inner ring portion and a ring-shaped irradiation portion, wherein the ring-shaped irradiation portion is connected to an outer edge of the inner ring portion, and the ring-shaped irradiation portion comprises a wavelength conversion region; a wavelength conversion layer, disposed on the wavelength conversion region; a pressure ring, pressing against the inner ring portion and having a first surface facing away the turntable; an anodized layer, disposed on the first surface; and a balance weight, disposed on the anodized layer, wherein the surface roughness of the anodized layer is 1 μm to 10 μm. ### Claim 2 (depends on 1) The wavelength conversion wheel according to claim 1, wherein a material of the pressure ring comprises at least one of aluminum, aluminum alloy, magnesium, magnesium alloy, titanium and titanium alloy. ### Claim 3 (depends on 1) The wavelength conversion wheel according to claim 1, wherein the anodized layer is formed by a process of plasma electrolytic oxidation or a process of micro-arc oxidation. ### Claim 4 (depends on 1) The wavelength conversion wheel according to claim 1, wherein the anodized layer comprises a ceramic structure layer. ### Claim 5 (depends on 1) The wavelength conversion wheel according to claim 1, wherein a thickness of the anodized layer is 10 μm to 100 μm. ### Claim 6 (depends on 1) The wavelength conversion wheel according to claim 1, wherein a thermal conductivity of the anodized layer is smaller than a thermal conductivity of the turntable. ### Claim 7 (depends on 1) The wavelength conversion wheel according to claim 1, wherein a thermal conductivity of the anodized layer is 0.5 to 10 W/(m·K). ### Claim 8 (depends on 1) The wavelength conversion wheel according to claim 1, wherein the pressure ring further has a second surface, the second surface is opposite to the first surface and faces the turntable, and the anodized layer is further disposed on the second surface. ### Claim 9 (depends on 8) The wavelength conversion wheel according to claim 8, further comprising a driving part, wherein the turntable is located between the driving part and the pressure ring, the second surface is attached to the inner ring portion, and the driving portion is adapted to drive the turntable to rotate. ### Claim 10 A projection device, comprising: an illumination system, providing an illumination beam; a light valve, disposed on a transmission path of the illumination beam to convert the illumination beam into an image beam; and a projection lens, disposed on a transmission path of the image beam, wherein the illumination system comprises an excitation light source and a wavelength conversion wheel, the excitation light source provides an excitation beam, and the wavelength conversion wheel comprises: a turntable, having an inner ring portion and a ring-shaped irradiation portion, wherein the ring-shaped irradiation portion is connected to an outer edge of the inner ring portion, and the ring-shaped irradiation portion comprises a wavelength conversion region; a wavelength conversion layer, disposed on the wavelength conversion region; a pressure ring, pressing against the inner ring portion and having a first surface facing away the turntable; an anodized layer, disposed on the first surface; and a balance weight, disposed on the anodized layer, wherein the surface roughness of the anodized layer is 1 μm to 10 μm, wherein the wavelength conversion device is disposed on a transmission path of the excitation beam, the wavelength conversion layer of the wavelength conversion device is adapted to convert the excitation beam into a converted beam, and the illumination beam comprises the converted beam and the excitation beam. ### Claim 11 (depends on 10) The projection device according to claim 10, wherein a material of the pressure ring comprises at least one of aluminum, aluminum alloy, magnesium, magnesium alloy, titanium and titanium alloy. ### Claim 12 (depends on 10) The projection device according to claim 10, wherein the anodized layer is formed by a process of plasma electrolytic oxidation or a process of micro-arc oxidation. ### Claim 13 (depends on 10) The projection device according to claim 10, wherein the anodized layer comprises a ceramic structure layer. ### Claim 14 (depends on 10) The projection device according to claim 10, wherein a thickness of the anodized layer is 10 μm to 100 μm. ### Claim 15 (depends on 10) The projection device according to claim 10, wherein a thermal conductivity of the anodized layer is smaller than a thermal conductivity of the turntable. ### Claim 16 (depends on 15) The projection device according to claim 15, wherein a thermal conductivity of the anodized layer is 0.5 to 10 W/(m·K). ### Claim 17 (depends on 10) The projection device according to claim 10, wherein the pressure ring further has a second surface, the second surface is opposite to the first surface and faces the turntable, and the anodized layer is further disposed on the second surface. ### Claim 18 (depends on 17) The projection device according to claim 17, further comprising a driving part, wherein the turntable is located between the driving part and the pressure ring, the second surface is attached to the inner ring portion, and the driving portion is adapted to drive the turntable to rotate.