# US 2018/0321577 A1 · Transparent screen > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0321577 A1 - Document ID: US20180321577A1 - Status: Published application - Kind: A1 - Application number: 16/015,513 - Filed: 2018-06-22 - Published: 2018-11-08 - Earliest claimed: 2015-12-25 - Assignees: FUJIFILM Corporation - Applicants: FUJIFILM Corporation - Inventors: Yujiro YANAI; Akira YAMAMOTO; Michio NAGAI - Web page: https://patentgrep.com/patent/US20180321577A1 ## CPC - G03B 21/60: characterised by the nature of the surface - G03B 21/604: Polarised screens - G03B 21/62: Translucent screens - G02F 1/133543: {Cholesteric polarisers} - G02F 2201/343: cholesteric liquid crystal reflector - G03B 21/28: Reflectors in projection beam {(in illumination beam G03B21/2066)} - 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) - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract According to the present invention, there is provided a plurality of protruding portions that are formed on one surface of the support and have inclined surfaces parallel to each other; a cholesteric liquid crystal layer that is formed on each of the inclined surfaces of the protruding portions; and an overcoat layer that is laminated on the surface of the support on which the protruding portions are formed so as to cover the cholesteric liquid crystal layer, in which a normal line of each of the inclined surfaces of the protruding portions is parallel to a spiral axis of the cholesteric structure of the cholesteric' liquid crystal layer, an angle formed between a normal line of a surface of the overcoat layer and the spiral axis of the cholesteric structure is 5° to 42°, a difference in refractive index between the cholesteric liquid crystal layer and the protruding portion and a difference in refractive index between the cholesteric liquid crystal layer and the overcoat layer are 0.2 or less. ## Claims ### Claim 1 A transparent screen comprising: a support that is capable of transmitting light; a plurality of protruding portions that are formed on one surface of the support and have inclined surfaces parallel to each other; a cholesteric liquid crystal layer that is formed on each of the inclined surfaces of the plurality of protruding portions and formed of a liquid crystal material having a cholesteric structure; and an overcoat layer that is laminated on the surface of the support, on which the plurality of protruding portions are formed, so as to cover the cholesteric liquid crystal layer, wherein a normal line of each of the inclined surfaces of the plurality of protruding portions is parallel to a spiral axis of the cholesteric structure of the cholesteric liquid crystal layer, an angle formed between a normal line of a surface of the overcoat layer and the spiral axis of the cholesteric structure of the cholesteric liquid crystal layer is 5° to 42°, a difference in refractive index between the cholesteric liquid crystal layer and the protruding portion is 0.2 or less, and a difference in refractive index between the cholesteric liquid crystal layer and the overcoat layer is 0.2 or less. ### Claim 2 (depends on 1) The transparent screen according to claim 1, wherein an angle of the spiral axis of the cholesteric structure of the cholesteric liquid crystal layer with respect to the surface of the overcoat layer is 15° to 25°. ### Claim 3 (depends on 1) The transparent screen according to claim 1, wherein the difference in refractive index between the cholesteric liquid crystal layer and the protruding portion is 0.05 or less, and the difference in refractive index between the cholesteric liquid crystal layer and the overcoat layer is 0.05 or less. ### Claim 4 (depends on 2) The transparent screen according to claim 2, wherein the difference in refractive index between the cholesteric liquid crystal layer and the protruding portion is 0.05 or less, and the difference in refractive index between the cholesteric liquid crystal layer and the overcoat layer is 0.05 or less. ### Claim 5 (depends on 1) The transparent screen according to claim 1, wherein the cholesteric liquid crystal layer is formed of two or more layers reflecting light of different wavelength regions. ### Claim 6 (depends on 4) The transparent screen according to claim 4, wherein the cholesteric liquid crystal layer is formed of two or more layers reflecting light of different wavelength regions. ### Claim 7 (depends on 1) The transparent screen according to claim 1, wherein in a cross section perpendicular to the surface of the overcoat layer and parallel to an inclination direction of the inclined surface of the plurality of protruding portions, a shape of the protruding portion is an obtuse-angled triangle, and an apex of the obtuse angle is formed on the surface side of the overcoat layer. ### Claim 8 (depends on 6) The transparent screen according to claim 6, wherein in a cross section perpendicular to the surface of the overcoat layer and parallel to an inclination direction of the inclined surface of the plurality of protruding portions, a shape of the protruding portion is an obtuse-angled triangle, and an apex of the obtuse angle is formed on the surface side of the overcoat layer. ### Claim 9 (depends on 1) A transparent screen that is formed by laminating two or more of the transparent screens according to claim 1, wherein cholesteric liquid crystal layers of the respective transparent screens reflect light of different wavelength regions. ### Claim 10 (depends on 8) A transparent screen that is formed by laminating two or more of the transparent screens according to claim 8, wherein cholesteric liquid crystal layers of the respective transparent screens reflect light of different wavelength regions.