# US 2010/0165299 A1 · Projector > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0165299 A1 - Document ID: US20100165299A1 - Status: Published application - Kind: A1 - Application number: 12/642,259 - Filed: 2009-12-18 - Published: 2010-07-01 - Earliest claimed: 2008-12-25 - Assignees: Seiko Epson Corporation - Inventors: Toshihiro SHIMIZU; Katsumi TANAKA - Web page: https://patentgrep.com/patent/US20100165299A1 ## CPC - G03B 21/28: Reflectors in projection beam {(in illumination beam G03B21/2066)} - G03B 21/208: {Homogenising, shaping of the illumination light} - G03B 33/12: using beam-splitting or beam-combining systems, e.g. dichroic mirrors - 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 projector includes: a light source that emits light; a first lens array that divides the light emitted from the light source into a plurality of partial light beams; a second lens array that focuses the plurality of partial light beams emitted from the first lens array; condenser lenses that superimpose the plurality of partial light beams emitted from the second lens array on target illumination regions; and liquid crystal panels that modulate the light beams passing through the condenser lenses according to image information, wherein each of the condenser lenses is a single lens that achieves telecentric illumination when superimposing the partial light beams, and only the condenser lenses are arranged as lenses between the second lens array and the liquid crystal panels. ## Claims ### Claim 1 A projector comprising: a light source that emits light; a first lens array that divides the light emitted from the light source into a plurality of partial light beams; a second lens array that focuses the plurality of partial light beams emitted from the first lens array; condenser lenses that superimpose the plurality of partial light beams emitted from the second lens array on target illumination regions, each of the condenser lenses being a single lens that achieves telecentric illumination when superimposing the partial light beams; and liquid crystal panels that modulate the light beams passing through the condenser lenses according to image information, the condenser lenses arranged as the only lenses between the second lens array and the liquid crystal panels. ### Claim 2 (depends on 1) The projector according to claim 1, each of the condenser lenses being arranged in a middle part when the length of an optical path from an emission-side surface of the second lens array to a light modulation surface of each of the liquid crystal panels is divided into three equal parts. ### Claim 3 (depends on 1) The projector according to claim 1, each of the condense lenses being provided at a position spaced a distance of (⅓)L to (⅔)L from the emission-side surface of the second lens array, when L is a distance from the emission-side surface of the second lens array to the image formation surface of the corresponding liquid crystal panel. ### Claim 4 (depends on 1) The projector according to claim 1, further comprising: a color separation light guide optical system including a first color separation mirror that separates the light beams emitted from the second lens array into a first color light component and other color light components, a second color separation mirror that separates other color light components into a second color light component and a third color light component, a first reflecting mirror that reflects the first color light component reflected by the first color separation mirror to bend an optical path, and second and third reflecting mirrors that reflect the third color light component passing through the second color separation mirror to bend an optical path, the condenser lenses being arranged between the first color separation mirror and the first reflecting mirror and between the first color separation mirror and the second color separation mirror. ### Claim 5 (depends on 1) The projector according to claim 1, further comprising: a color separation light guide optical system including a first-stage reflecting mirror that reflects the light beams emitted from the second lens array to bend an optical path, a first color separation mirror that separates the light beams reflected by the first-stage reflecting mirror into a first color light component and other color light components, a second color separation mirror that separates other color light components into a second color light component and a third color light component, a first reflecting mirror that reflects the first color light component reflected by the first color separation mirror to bend an optical path, and second and third reflecting mirrors that reflect the third color light component passing through the second color separation mirror to bend an optical path, the condenser lens being arranged between the first-stage reflecting mirror and the first color separation mirror. ### Claim 6 (depends on 4) The projector according to claim 4, further comprising: first, second, and third liquid crystal panels that respectively modulate the first, second, and third color light components separated by the color separation light guide optical system according to image information; a light composition optical system that composes the images of the first, second, and third color light components modulated by the first, second, and third liquid crystal panels; and a projection optical system that projects the image light composed by the light composition optical system. ### Claim 7 (depends on 4) The projector according to claim 4, the color separation light guide optical system further including a relay lens that is provided on the optical path of the third color light component having the largest length. ### Claim 8 (depends on 1) The projector according to claim 1, each of the condenser lenses being a biconvex lens. ### Claim 9 (depends on 1) The projector according to claim 1, each of the condenser lenses being an aspheric lens. ### Claim 10 (depends on 1) The projector according to claim 1, each of the condenser lenses being a spherical lens. ### Claim 11 A projector comprising: a light source that emits light; a first lens array that divides the light emitted from the light source into a plurality of partial light beams; a second lens array that focuses the plurality of partial light beams emitted from the first lens array; a single condenser lens that superimposes the plurality of partial light beams emitted from the second lens array on target illumination regions, the condenser lens being a single lens that achieves telecentric illumination when superimposing the partial light beams; and liquid crystal panels that modulate the light beams passing through the condenser lenses according to image information, the liquid crystal panels including a first liquid crystal panel and a liquid second crystal panel, the condenser lens arranged as the only lens between the second lens array and the first liquid crystal panel and the condenser lens arranged as the only lens between the second lens array and the second liquid crystal panel. ### Claim 12 (depends on 11) The projector according to claim 11, the condenser lens being arranged in a middle part when the length of an optical path from an emission-side surface of the second lens array to a light modulation surface of each of the liquid crystal panels is divided into three equal parts. ### Claim 13 (depends on 11) The projector according to claim 11, the condense lenses being provided at a position spaced a distance of (⅓)L to (⅔)L from the emission-side surface of the second lens array, when L is a distance from the emission-side surface of the second lens array to the image formation surface of the first liquid crystal panel. ### Claim 14 (depends on 11) The projector according to claim 11, further comprising: a color separation light guide optical system including a first color separation mirror that separates the light beams emitted from the second lens array into a first color light component and other color light components, a second color separation mirror that separates other color light components into a second color light component and a third color light component, a first reflecting mirror that reflects the first color light component reflected by the first color separation mirror to bend an optical path, and second and third reflecting mirrors that reflect the third color light component passing through the second color separation mirror to bend an optical path, the condenser lens being arranged between the second lens array and a first color separation mirror. ### Claim 15 (depends on 11) The projector according to claim 11, further comprising: a color separation light guide optical system including a first-stage reflecting mirror that reflects the light beams emitted from the second lens array to bend an optical path, a first color separation mirror that separates the light beams reflected by the first-stage reflecting mirror into a first color light component and other color light components, a second color separation mirror that separates other color light components into a second color light component and a third color light component, a first reflecting mirror that reflects the first color light component reflected by the first color separation mirror to bend an optical path, and second and third reflecting mirrors that reflect the third color light component passing through the second color separation mirror to bend an optical path, the condenser lens being arranged between the first-stage reflecting mirror and the first color separation mirror. ### Claim 16 (depends on 14) The projector according to claim 14, the liquid crystal panels further including a third liquid crystal panel, the first, second, and third liquid crystal panels being respectively modulate the first, second, and third color light components separated by the color separation light guide optical system according to image information, the projector further comprising: a light composition optical system that composes the images of the first, second, and third color light components modulated by the first, second, and third liquid crystal panels; and a projection optical system that projects the image light composed by the light composition optical system. ### Claim 17 (depends on 14) The projector according to claim 14, the color separation light guide optical system further including a relay lens that is provided on the optical path of the third color light component having the largest length. ### Claim 18 (depends on 11) The projector according to claim 11, the condenser lens being a biconvex lens. ### Claim 19 (depends on 11) The projector according to claim 11, the condenser lens being an aspheric lens. ### Claim 20 (depends on 11) The projector according to claim 11, the condenser lens being a spherical lens.