# US 11,307,487 B2 · Laser illumination device and projection system 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 11,307,487 B2 - Document ID: US11307487B2 - Status: Granted - Kind: B2 - Application number: 16/616,394 - Filed: 2017-08-01 - Published: 2020-09-24 - Granted: 2022-04-19 - Earliest claimed: 2017-05-24 - Assignees: Appotronics Corporation Limited - Applicants: Appotronics Corporation Limited - Inventors: Fei Hu; Zuqiang Guo; Peng Du; Yi Li - Web page: https://patentgrep.com/patent/US11307487B2 ## CPC - G03B 21/2033: {LED or laser light sources} - H04N 9/3167: {for polarizing the light beam (polarizing optical systems per se G02B27/28)} - F21V 5/004: {using microlenses} - G02B 27/09: Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for {(adapting the beam shape of a laser diode G02B19/0052; adapting the beam shape of an LED G02B19/0061; coupling into light guides using intermediate optical elements G02B6/4204; beam shaping specially adapted for lasers H01S3/005)} - G02B 27/10: Beam splitting or combining systems (polarising systems G02B27/28; mixing and splitting light signals using optical waveguides G02B6/28; {beam shaping, e.g. changing the cross-sectional area, by dividing or superposing multiple light beams G02B27/0905}) - G02B 27/30: Collimators - G03B 21/20: Lamp housings - G03B 21/2013: {Plural light sources} - G03B 21/2053: {Intensity control of illuminating light (controlled by video signal processing H04N5/74 or H04N9/31)} - G03B 21/2066: {Reflectors in illumination beam (in projection beam G03B21/28)} - G03B 21/2073: {Polarisers in the lamp house (peculiar to electronic spatial light modulators H04N9/3197)} - H04N 9/3126: {for spatial light modulators in series} - H04N 9/3129: {scanning a light beam on the display screen (scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161)} - H04N 9/3161: {using laser light sources (using laser beams scanning the display screen H04N9/3129)} - H04N 9/3164: {using multiple light sources} - H05B 47/155: Coordinated control of two or more light sources - 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 - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract A laser illumination device and a projection system including the same. The laser illumination device includes a laser source, a light combining assembly, a micro-lens assembly, and a plurality of cylindrical lens assemblies; the plurality of cylindrical lens assemblies are provided in a light transmission path of the laser source; the micro-lens assembly is mounted at one side of the light combining assembly; each cylindrical lens assembly includes a first cylindrical lens array and a second cylindrical lens array; and the first cylindrical lens array and the second cylindrical lens array form a preset angle. ## Claims ### Claim 1 A laser illumination device for a projection system, comprising: a laser light source; a light combining assembly; a micro-lens assembly; and a plurality of cylindrical lens assemblies, wherein the plurality of cylindrical lens assemblies is provided in an optical path for transmission of the laser light source, and the micro-lens assembly is provided on one side of the light combining assembly; wherein each of the plurality of cylindrical lens assemblies comprises a first cylindrical lens array and a second cylindrical lens array, and a preset angle of intersection is formed between the first cylindrical lens array and the second cylindrical lens array; wherein the laser light source is configured to achieve grayscale output of the projection system for a corresponding pixel point by adjusting luminance of the laser light source; and wherein the first cylindrical lens array and the second cylindrical lens array are configured to adjust divergence angles of a laser beam from the laser light source which has a spatial distribution in a shape of rectangle, such that divergence angles of the laser beam with respect to a length direction and a width direction of the rectangle are same. ### Claim 2 (depends on 1) The laser illumination device according to claim 1, wherein the first cylindrical lens array and the second cylindrical lens array are perpendicular to each other. ### Claim 3 (depends on 1) The laser illumination device according to claim 1, wherein the laser light source comprises a red light source outputting red laser light, a green light source outputting green laser light, and a blue light source outputting blue laser light, and the plurality of cylindrical lens assemblies comprises three cylindrical lens assemblies which are respectively provided in the optical path for transmission of the red light source, the green light source and the blue light source. ### Claim 4 (depends on 3) The laser illumination device according to claim 3, wherein a wavelength of the red laser light output by the red light source is 638 nm, a wavelength of the green laser light output by the green light source is 520 nm, and a wavelength of the blue laser light output by the blue light source is 455 nm. ### Claim 5 (depends on 1) The laser illumination device according to claim 1, wherein a focal length of the first cylindrical lens array and a focal length of the second cylindrical lens array are set base on a formula of h 1 f 1 = h 2 f 2 , such that divergence angles of the laser beam with respect to a length direction and a width direction of the rectangle are same, wherein h1 is a dimension of the spatial distribution in a shape of rectangle with respect to a length direction, h2 is a dimension of the spatial distribution in a shape of rectangle with respect to a width direction, f1 is the focal length of the first cylindrical lens array, and f2 is the focal length of the second cylindrical lens array. ### Claim 6 A projection system comprising: a laser illumination device, comprising a laser light source, a light combining assembly, a micro-lens assembly, and a plurality of cylindrical lens assemblies, wherein the plurality of cylindrical lens assemblies is provided in an optical path for transmission of the laser light source, and the micro-lens assembly is provided on one side of the light combining assembly, and wherein each of the plurality of cylindrical lens assemblies comprises a first cylindrical lens array and a second cylindrical lens array, and a preset angle of intersection is formed between the first cylindrical lens array and the second cylindrical lens array; and wherein the laser light source is configured to achieve grayscale output of the projection system for a corresponding pixel point by adjusting luminance of the laser light source; a diffuser provided in an optical path, along which the laser illumination device transmits a laser beam outwards; a square rod assembly provided on one side of the diffuser facing away from the laser illumination device; a light modulation assembly; and a light relay assembly provided between the square rod assembly and the light modulation assembly; an output assembly provided in an optical path, along which the light modulation assembly transmits a modulated laser beam outwards, wherein the light modulation assembly is configured to adjust output luminance of the laser light source corresponding to each pixel point in an image signal, and to control the laser light source to achieve grayscale output of the projection system for a corresponding pixel point by adjusting luminance of the laser light source; and wherein if a grayscale value of a pixel point having the highest luminance obtained by an algorithm in the image signal obtained by the projection system is A, a maximum value of the luminance of the laser light source corresponding to the pixel point having the highest luminance is Imax, and a grayscale value of a certain pixel point is a, then a luminance Ia of the laser light source corresponding to the certain pixel point is calculated based on a formula of I a = I max × a A , to achieve projection imaging of the projection system with a high dynamic range. ### Claim 7 (depends on 6) The projection system according to claim 6, wherein the light modulation assembly is a spatial light modulator. ### Claim 8 (depends on 7) The projection system according to claim 7, wherein the output assembly is an imaging object lens. ### Claim 9 (depends on 6) The projection system according to claim 6, wherein the laser light source comprises a red light source outputting red laser light, a green light source outputting green laser light, and a blue light source outputting blue laser light, the output assembly is a scanning mirror configured to acquire an RGB signal of a certain pixel point in a picture and video signal and the light modulation assembly is configured to control the laser light source in the laser illumination device to output light intensity based on the acquired RGB signal, if an RGB signal of a certain pixel point in a picture and video signal acquired by the scanning mirror is (x, y, z), a maximum light intensity of the red laser light output by the red light source is IR, a maximum light intensity of the green laser light output by the green light source is IG, a maximum grayscale of the laser light source is IL, then a light intensity of the red laser light output by the red light source is IR*X/IL, a light intensity of the green laser light output by the green light source is IG*y/IL, and a light intensity of the blue laser light output by the blue light source is IB*Z/IL. ### Claim 10 (depends on 6) The projection system according to claim 6, wherein the laser light source is of an 8-bit grayscale, and a maximum grayscale IL of the laser light source is 255. ### Claim 11 (depends on 6) The projection system according to claim 6, further comprising a light recycling assembly, wherein the light recycling assembly comprises an LCD modulator, a PBS plate, a reflector assembly, a half-wave plate, a relay lens and a light combining mirror, wherein the reflector assembly comprises a first reflector and a second reflector, the LCD modulator and the PBS plate are sequentially provided between the square rod assembly and the light relay assembly, the half-wave plate and the relay lens are sequentially provided between the first reflector and the second reflector, and the light combining mirror is provided between the laser illumination device and the square rod assembly. ### Claim 12 (depends on 11) The projection system according to claim 11, wherein if a grayscale of the pixel point having the highest luminance obtained by an algorithm in the image signal obtained by the projection system is A, the maximum luminance that can be output by the laser light source is denoted as Imax, a maximum grayscale of the LCD modulator is IM, and a gray value of a certain pixel point is a, then a luminance Ia of the laser light source corresponding to the certain pixel point is obtained by calculating based on a formula of I a = I max × a A , and a luminance Ib of the LCD modulator corresponding to the certain pixel point is obtained by calculating based on a formula of I b = I M × a A . ### Claim 13 (depends on 11) The projection system according to claim 11, wherein each of the laser light source, the light modulation assembly and the LCD modulator has a certain gray level, and the gray level that can be achieved by the projection system is a product of the certain gray level of the laser light source, the certain gray level of the light modulation assembly and the certain gray level of the LCD modulator. ### Claim 14 (depends on 11) The projection system according to claim 11, wherein the light combining mirror comprises an AR-coating film and a high-reflective film, and the AR-coating film is embedded in the high-reflective film. ### Claim 15 (depends on 6) The projection system according to claim 6, wherein if a luminance of a pixel point having the highest luminance in the image signal obtained by the projection system is A, a luminance of each pixel point is a, a maximum luminance that can be output by the laser light source is Imax, and the laser light source is configured to output laser light with a luminance of Ia for each pixel point based I a = I max × a A , on to achieve projection imaging of the projection system with a high dynamic range. ### Claim 16 (depends on 11) The projection system according to claim 11, wherein the LCD modulator is of an 8-bit gray level, and a maximum grayscale IM of the LCD modulator is 255. ### Claim 17 A laser illumination device for a projection system, comprising: a laser light source; a light combining assembly; a micro-lens assembly; and a plurality of cylindrical lens assemblies, wherein the plurality of cylindrical lens assemblies is provided in an optical path for transmission of the laser light source, and the micro-lens assembly is provided on one side of the light combining assembly, wherein each of the plurality of cylindrical lens assemblies comprises a first cylindrical lens array and a second cylindrical lens array, and a preset angle of intersection is formed between the first cylindrical lens array and the second cylindrical lens array, wherein the first cylindrical lens array and the second cylindrical lens array are configured to adjust divergence angles of a laser beam from the laser light source which has a spatial distribution in a shape of rectangle, such that divergence angles of the laser beam with respect to a length direction and a width direction of the rectangle are same. ### Claim 18 A laser illumination device for a projection system, comprising: a laser light source configured to emit at least one laser beam; a light combining assembly; a micro-lens assembly; and a plurality of cylindrical lens assemblies, wherein each of the at least one laser beam corresponds one of the plurality of cylindrical lens assemblies, the light combining assembly is configured to combine a plurality of laser beams emitted by the plurality of cylindrical lens assemblies, and the combined laser beams are incident to the micro-lens assembly and then is emitted from the laser illumination device; h1 is a dimension with respect to a length direction of one of the at least one laser beam, h2 is a dimension with respect to a width direction of the laser beam; the plurality of cylindrical lens assemblies is provided in an optical path for transmission of the laser light source, each of the plurality of cylindrical lens assemblies comprises a first cylindrical lens array and a second cylindrical lens array, f1 is a focal length of the first cylindrical lens array, f2 is a focal length of the second cylindrical lens array, and a preset angle of intersection is formed between the first cylindrical lens array and the second cylindrical lens array; wherein the first cylindrical lens array, the second cylindrical lens array, and the laser beam satisfy: h 1 f 1 = h 2 f 2 , to form a uniform matrix light after the laser beam passes through one of the plurality of cylindrical lens assemblies, such that grayscale output of the projection system for a corresponding pixel point is achieved by adjusting luminance of each of the at least one laser light; wherein the uniform matrix light has divergence angles of the laser beam in two orthogonal directions and the divergence angles are the same.