# US 2020/0401025 A1 · Laser projection apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0401025 A1 - Document ID: US20200401025A1 - Status: Published application - Kind: A1 - Application number: 16/800,035 - Filed: 2020-02-25 - Published: 2020-12-24 - Earliest claimed: 2019-06-20 - Assignees: Hisense Laser Display Co., Ltd - Applicants: Hisense Laser Display Co., Ltd. - Inventors: Kan ZHOU; Zhe XING; Lei CUI - Web page: https://patentgrep.com/patent/US20200401025A1 ## CPC - G03B 21/16: Cooling; Preventing overheating - G03B 21/2013: {Plural light sources} - G03B 21/2033: {LED or laser light sources} - H01S 5/02407: {Active cooling, e.g. the laser temperature is controlled by a thermo-electric cooler or water cooling} - H01S 5/02423: {Liquid cooling, e.g. a liquid cools a mount of the laser} - H01S 5/02438: {Characterized by cooling of elements other than the laser chip, e.g. an optical element being part of an external cavity or a collimating lens} - H01S 5/4093: {Red, green and blue [RGB] generated directly by laser action or by a combination of laser action with nonlinear frequency conversion} - H05K 7/20145: {Means for directing air flow, e.g. ducts, deflectors, plenum or guides} - H05K 7/20154: {Heat dissipaters coupled to components} - H05K 7/20172: {Fan mounting or fan specifications} - H05K 7/20272: {Accessories for moving fluid, for expanding fluid, for connecting fluid conduits, for distributing fluid, for removing gas or for preventing leakage, e.g. pumps, tanks or manifolds} - H05K 7/20336: {Heat pipes, e.g. wicks or capillary pumps} - H01S 5/005: {Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping (H01S5/026, H01S5/18388 take precedence)} - H01S 5/02216: Butterfly-type, i.e. with electrode pins extending horizontally from the housings - H01S 5/02253: using lenses - H01S 5/4025: {Array arrangements, e.g. constituted by discrete laser diodes or laser bar (H01S5/42 takes precedence)} - 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) - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract Embodiments of the present disclosure describe a laser projection apparatus. The laser projection apparatus includes a laser source system, an optical engine, a lens system that are sequentially connected in a laser beam propagation direction, a plurality of circuit boards, a first heat dissipation system, and a second heat dissipation system. The first heat dissipation system is configured to dissipate heat of a first laser assembly in the laser source system, the optical engine, and the plurality of circuit boards, and to make airflow sequentially flow through the above components to form a first heat dissipation path. The second heat dissipation system is configured to dissipate heat of a second laser assembly in the laser source system, the lens system, and the plurality of circuit boards, and to make airflow sequentially flow through the above components to form a second heat dissipation path. ## Claims ### Claim 1 A laser projection apparatus, comprising: a laser source system, an optical engine, and a lens system that are sequentially connected along a laser beam propagation direction; a plurality of circuit boards; a first heat dissipation system, wherein the first heat dissipation system is configured to dissipate heat of a first laser assembly in the laser source system, the optical engine and the plurality of circuit boards, and to make airflow sequentially flow through the first laser assembly, the optical engine and the plurality of circuit boards to form a first heat dissipation path; and a second heat dissipation system, wherein the second heat dissipation system is configured to dissipate heat of a second laser assembly in the laser source system, the lens system and the plurality of circuit boards, and to make airflow sequentially flow through the second laser assembly, the lens system and the plurality of circuit boards to form a second heat dissipation path. ### Claim 2 (depends on 1) The laser projection apparatus according to claim 1, wherein: the first heat dissipation system comprises a liquid-cooling heat dissipation device; the liquid-cooling heat dissipation device comprises a first cooling head, a cooling drain, and a plurality of pipes with cooling medium inside; and the first cooling head and the cooling drain are connected through at least one of the plurality of pipes, and the first cooling head is disposed on a first side wall of a housing of the laser source system. ### Claim 3 (depends on 2) The laser projection apparatus according to claim 2, wherein: the liquid-cooling heat dissipation device further comprises a second cooling head; and the second cooling head is connected to the first cooling head and the cooling drain through at least one of the plurality of pipes, and the second cooling head is disposed on a back surface of a laser valve of the optical engine. ### Claim 4 (depends on 3) The laser projection apparatus according to claim 3, wherein: the first cooling head comprises a first cooling medium inlet and a first cooling medium outlet; the second cooling head comprises a second cooling medium inlet and a second cooling medium outlet; and the first cooling medium inlet is connected to the cooling drain, the first cooling medium outlet is connected to the second cooling medium inlet, and the second cooling medium outlet is connected to the cooling drain. ### Claim 5 (depends on 2) The laser projection apparatus according to claim 2, wherein: the first laser assembly is installed on the first side wall of the housing of the laser source system; the first laser assembly comprises a red laser assembly, and the red laser assembly is in contact with the first cooling head. ### Claim 6 (depends on 2) The laser projection apparatus according to claim 2, further comprising: an apparatus housing comprising an air inlet and an air outlet; and wherein the first heat dissipation system further comprises at least one of the following: a first fan disposed at the air inlet and configured to drive airflow toward the optical engine so as to sequentially flow through the cooling drain, the optical engine, and a portion of the plurality of circuit boards disposed downstream of the optical engine along the first heat dissipation path, or a fourth fan disposed at the air outlet and configured to discharge airflow from flowing through the cooling drain, the optical engine and the plurality of circuit boards out of the apparatus housing. ### Claim 7 (depends on 6) The laser projection apparatus according to claim 6, wherein: the first laser assembly comprises a red laser assembly; the first fan is disposed at a side of the cooling drain away from the first cooling head in the first heat dissipation path; and the fourth fan is located at a side of the plurality of circuit boards away from the red laser assembly in the first heat dissipation path. ### Claim 8 (depends on 1) The laser projection apparatus according to claim 1, wherein the second heat dissipation system comprises: an air-cooling heat dissipation device, wherein: the air-cooling heat dissipation device comprises at least one first heat dissipation fin, a plurality of heat pipes, and a heat conducting plate, and the plurality of heat pipes are fixed on a second side wall of a housing of the laser source system through the heat conducting plate and extend into the at least one first heat dissipation fin. ### Claim 9 (depends on 8) The laser projection apparatus according to claim 8, wherein: the second laser assembly is installed on the second side wall of the housing of the laser source system; the second laser assembly comprises a blue laser assembly and a green laser assembly; and a side of the second laser assembly is connected with the plurality of heat pipes through the heat conducting plate. ### Claim 10 (depends on 9) The laser projection apparatus according to claim 9, wherein the plurality of heat pipes comprises one of the following: a first set of heat pipes, wherein the first set of heat pipes is connected to a region of the heat conducting plate corresponding to the blue laser assembly; a second set of heat pipes, wherein the second set of heat pipes is connected to a region of the heat conducting plate corresponding to the green laser assembly; or a third set of heat pipes, wherein the third set of heat pipes is connected to a region of heat conducting plate corresponding to the blue laser assembly and the green laser assembly. ### Claim 11 (depends on 9) The laser projection apparatus according to claim 9, wherein: the at least one first heat dissipation fin comprises: a third fin portion corresponding to the blue laser assembly, and a fourth fin portion corresponding to the green laser assembly; and the laser projection apparatus further comprises a fifth fan disposed between the third fin portion and the fourth fin portion. ### Claim 12 (depends on 8) The laser projection apparatus according to claim 8, wherein the second heat dissipation system further comprises one of the following: a second fan disposed at a side of the at least one first heat dissipation fin away from the plurality of circuit boards, and configured to drive airflow to sequentially flow through the at least one first heat dissipation fin, the lens system, and a portion of the plurality of circuit boards located downstream of the lens system along the second heat dissipation path, or a third fan disposed between the at least one first heat dissipation fin and the lens system, and configured to blow airflow from flowing through the at least one first heat dissipation fin toward the lens system. ### Claim 13 (depends on 8) The laser projection apparatus according to claim 8, wherein: a surface of the heat conducting plate connected to the second laser assembly comprises a plane; a surface of the heat conducting plate connected to the plurality of heat pipes comprises a plurality of grooves, and a portion of each of the plurality of heat pipes is disposed in a corresponding one of the plurality of grooves; and each of the at least one first heat dissipation fin comprises a plurality of through holes, and another portion of each of the plurality of heat pipes is disposed in a corresponding one of the plurality of through holes. ### Claim 14 (depends on 8) The laser projection apparatus according to claim 8, wherein the air-cooling heat dissipation device further comprises: a second heat dissipation fin disposed between the plurality of heat pipes and the at least one first heat dissipation fin, and in contact with the plurality of heat pipes and the heat conducting plate. ### Claim 15 (depends on 14) The laser projection apparatus according to claim 14, wherein the plurality of heat pipes are arranged in at least one of the following ways: the heat conducting plate comprising a plurality of first grooves, and a portion of each of the plurality of heat pipes is embedded in a corresponding one of the plurality of first grooves; or, the second heat dissipation fin comprising a plurality of second grooves, and a portion of each of the plurality of heat pipes is embedded in a corresponding one of the plurality of second grooves. ### Claim 16 (depends on 14) The laser projection apparatus according to claim 14, wherein: the second laser assembly comprises a blue laser assembly and a green laser assembly; and the second heat dissipation fin comprises: a first fin portion in contact with a region of the heat conducting plate corresponding to the blue laser assembly, and a second fin portion in contact with a region of the heat conducting plate corresponding to the green laser assembly. ### Claim 17 (depends on 1) The laser projection apparatus according to claim 1, wherein: the first laser assembly comprises a red laser assembly, and the second laser assembly comprises a green laser assembly and a blue laser assembly; an operating temperature of the red laser assembly is less than or equal to 50° C.; an operating temperature of the blue laser assembly is less than or equal to 70° C.; an operating temperature of the green laser assembly is less than or equal to 65° C.; an operating temperature of a laser valve in the optical engine is less than or equal to 65° C.; an operating temperature of the lens system is less than or equal to 85° C.; and an operating temperature of the plurality of circuit boards is within a range of 80° C. to 120° C., inclusive. ### Claim 18 A laser projection apparatus, comprising: a laser source system, an optical engine, a lens system that are sequentially connected along a laser beam propagation direction; a plurality of circuit boards; and a third heat dissipation system comprising: a liquid-cooling heat dissipation device comprising a first cooling head, a cooling drain, and a plurality of pipes with cooling medium inside, wherein the first cooling head and the cooling drain are connected through at least one of the plurality of pipes, and the first cooling head is disposed on a first side wall of a housing of the laser source system, an air-cooling heat dissipation device comprising at least one first heat dissipation fin, a plurality of heat pipes, and a heat conducting plat, wherein the plurality of heat pipes are fixed on a second side wall of the housing of the laser source system through the heat conducting plate and extend into the at least one first heat dissipation fin, and a fan assembly configured to drive airflow to sequentially flow through the cooling drain, the at least one first heat dissipation fin and the plurality of circuit boards to form a third heat dissipation path. ### Claim 19 (depends on 18) The laser projection apparatus according to claim 18, wherein: the liquid-cooling heat dissipation device further comprises a second cooling head; the second cooling head is connected to the first cooling head and the cooling drain through at least one of the plurality of pipes; and the second cooling head is disposed on a back surface of a laser valve in the optical engine. ### Claim 20 (depends on 18) The laser projection apparatus according to claim 18, further comprising: an apparatus housing comprising an air inlet and an air outlet; and wherein the fan assembly comprises at least one of the following: a first fan disposed at the air inlet and configured to drive airflow to sequentially blow through the cooling drain, the at least one first heat dissipation fin, the lens system, and the plurality of circuit boards, a second fan disposed at a side of the at least one first heat dissipation fin proximate to the cooling drain, and configured to blow airflow to flow through the cooling drain toward the at least one first heat dissipation fin, the lens system, and the plurality of circuit boards, a third fan disposed at a side of the at least one first heat dissipation fin proximate to the plurality of circuit boards, and configured to blow airflow to flow through the at least one first heat dissipation fin toward the lens system and the plurality of circuit boards, or a fourth fan disposed at the air outlet, and configured to discharge airflow from flowing through the cooling drain, the at least one first heat dissipation fin, the optical engine, the lens system, and the plurality of circuit boards out of the apparatus housing.