# US 9,436,020 B2 · Luminance adjustment film and illuminating device including photothermal conversion material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,436,020 B2 - Document ID: US9436020B2 - Status: Granted - Kind: B2 - Application number: 13/980,027 - Filed: 2012-12-05 - Published: 2015-11-05 - Granted: 2016-09-06 - Earliest claimed: 2012-12-05 - Assignees: Empire Technology Development LLC - Applicants: Empire Technology Development LLC - Inventors: Masahiro Ueda - Web page: https://patentgrep.com/patent/US9436020B2 ## CPC - F21V 9/40: with provision for controlling spectral properties, e.g. colour, or intensity - G02B 6/0033: {Means for improving the coupling-out of light from the light guide} - G02B 6/0065: {Manufacturing aspects; Material aspects} - G02B 6/0068: {Arrangements of plural sources, e.g. multi-colour light sources} - G02F 1/0063: {Optical properties, e.g. absorption, reflection or birefringence (materials for non-linear optics G02F1/355)} - G02F 1/0147: {based on thermo-optic effects (G02F1/132 takes precedence)} - G02B 6/0058: {varying in density, size, shape or depth along the light guide} - Y10T 29/49828: Progressively advancing of work assembly station or assembled portion of work - 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 - 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 - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Luminance adjustment films that include a photothermal conversion material which converts infrared light to heat wherein an intensity distribution of the infrared light reflects a luminance distribution of visible light; and at least one microcapsule containing a compound which selectively decreases luminance of the visible light in reaction to the heat are described. ## Claims ### Claim 1 An illuminating device comprising: a visible light source configured to emit visible light; an infrared light source configured to emit infrared light having an intensity distribution which is proportionally related to a luminance distribution of the visible light; and a luminance adjustment film including a photothermal conversion material which converts the infrared light to heat and at least one microcapsule containing a compound which selectively decreases luminance of the visible light in reaction to the heat. ### Claim 2 (depends on 1) The illuminating device of claim 1, wherein the visible light source comprises an LED light source. ### Claim 3 (depends on 1) The illuminating device of claim 1, wherein the infrared light source comprises a semiconductor laser, a YAG laser, or a xenon laser. ### Claim 4 (depends on 1) The illuminating device of claim 1, wherein the heat causes a temperature distribution which reflects a luminance distribution of the visible light. ### Claim 5 (depends on 1) The illuminating device of claim 1, wherein the compound has a cloud point. ### Claim 6 (depends on 5) The illuminating device of claim 5, wherein the compound selectively scatters the visible light so as to selectively decrease the luminance of the visible light when a temperature of the compound is greater than or equal to the cloud point. ### Claim 7 (depends on 6) The illuminating device of claim 6, wherein the compound is precipitated in the at least one microcapsule so as to selectively scatter the visible light. ### Claim 8 A method of manufacturing an illuminating device, the method comprising: providing a visible light source configured to emit visible light; providing an infrared light source configured to emit infrared light having an intensity distribution which reflects a luminance distribution of the visible light; providing a photothermal conversion material which converts the infrared light to heat; providing at least one microcapsule containing a compound which selectively decreases luminance of the visible light in reaction to the heat; combining the at least one microcapsule with the photothermal conversion material to produce a luminance adjustment film; and combining the luminance adjustment film with the visible light source and the infrared light source to produce the illuminating device. ### Claim 9 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein the compound has a cloud point. ### Claim 10 (depends on 9) The method of manufacturing an illuminating device of claim 9, wherein the visible light passes through the compound when a temperature of the compound is less than the cloud point. ### Claim 11 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein the at least one microcapsule contains a plurality of compounds each having different cloud points from one another. ### Claim 12 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein the at least one microcapsule contains a solvent in which the compound is dissolved. ### Claim 13 (depends on 12) The method of manufacturing an illuminating device of claim 12, wherein the solvent comprises dimethylformamide, N-methylpyrrolidone, glycerin, polypropylene glycol, or polyethyleneglycol. ### Claim 14 (depends on 12) The method of manufacturing an illuminating device of claim 12, wherein the solvent further comprises water. ### Claim 15 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein a thickness of the luminance adjustment film is from about 1 micrometer to about 1 centimeter. ### Claim 16 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein an area of the luminance adjustment film is from about 25 square centimeters to about 25,000 square centimeters. ### Claim 17 (depends on 8) The method of manufacturing an illuminating device of claim 8, wherein the at least one microcapsule comprises a plurality of microcapsules uniformly distributed in the luminance adjustment film. ### Claim 18 (depends on 17) The method of manufacturing an illuminating device of claim 17, wherein a ratio of the plurality of microcapsules to the luminance adjustment film is from about 0.1% to about 90% by weight. ### Claim 19 A method of adjusting luminance, the method comprising: emitting visible light from a visible light source; emitting infrared light from an infrared light source, the infrared light having an intensity distribution which reflects a luminance distribution of the visible light; converting the infrared light to heat by using a photothermal conversion material; and selectively decreasing luminance of the visible light in reaction to the heat by providing at least one microcapsule containing a compound having a cloud point. ### Claim 20 (depends on 19) The method of adjusting luminance of claim 19, wherein the photothermal conversion material is selected from the group consisting of: phthalocyanine compounds, cyanine, dithiol metal complexes, naphthoquinone, anthraquinone dyes, aluminum, immonium dyes, and azo dyes. ### Claim 21 (depends on 19) The method of adjusting luminance of claim 19, wherein the compound is selected from the group consisting of: hydroxypropylcellulose, polyvinyl methyl ether, polyethylene oxide-polypropylene oxide copolymer, polyvinyl acetate partial hydrolysate, poly (N,N dimethyl aminoethyl acrylamide), and poly (N-isopropyl acrylamide). ### Claim 22 (depends on 19) The method of adjusting luminance of claim 19, further comprising a transparent resin in which the photothermal conversion material and the at least one microcapsule are contained. ### Claim 23 (depends on 22) The method of adjusting luminance of claim 22, wherein the transparent resin comprises polyethylene, polypropylene, cyclo olefin polymer, polystyrene, polyacrylonitrile, polymethyl methacrylate, polyamide, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalene, or triacetyl cellulose. ### Claim 24 (depends on 19) The method of adjusting luminance of claim 19, wherein the cloud point ranges about 20 degrees Celsius to 75 degrees Celsius. ### Claim 25 (depends on 19) The method of adjusting luminance of claim 19, wherein the cloud point ranges about 40 degrees Celsius to 60 degrees Celsius. ### Claim 26 (depends on 19) The method of adjusting luminance of claim 19, wherein the at least one microcapsule is coated with a polycondensation resin. ### Claim 27 (depends on 26) The method of adjusting luminance of claim 26, wherein the polycondensation resin is formed of a melamine resin, a urea resin, a gelatin resin, a urethane resin, or a polyurea resin.