# US 8,569,948 B2 · Electroluminescent devices and methods of making electroluminescent devices including an optical spacer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,569,948 B2 - Document ID: US8569948B2 - Status: Granted - Kind: B2 - Application number: 11/024,202 - Filed: 2004-12-28 - Published: 2006-06-29 - Granted: 2013-10-29 - Earliest claimed: 2004-12-28 - Assignees: Samsung Display Co., Ltd. - Applicants: Martin B Wolk; Robert L. Brott; Thomas R. Hoffend - Inventors: Martin B Wolk; Robert L. Brott; Thomas R. Hoffend - Web page: https://patentgrep.com/patent/US8569948B2 ## CPC - H05B 33/22: characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers - H10K 59/35: comprising red-green-blue [RGB] subpixels - H10K 59/38: comprising colour filters or colour changing media [CCM] - H10K 59/876: {comprising a resonant cavity structure, e.g. Bragg reflector pair} - H10H 20/862: {Resonant cavity structures (formed by reflecting means in the bodies H10H20/8142)} - Y02E 10/549: Organic PV cells - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract An electroluminescent device and a method of making an electroluminescent device that includes one or more optical spacers are disclosed. In one embodiment, the method includes forming an electroluminescent element on a substrate. The method further includes selectively thermally transferring an optical spacer. ## Claims ### Claim 1 A method of making an electroluminescent device, the method comprising: forming an electroluminescent element on a substrate, wherein the electroluminescent element comprises a cathode; an anode; and at least a portion of a plurality of sub-pixels; and selectively thermally transferring a plurality of optical spacers and a plurality of partially reflective layers to a side of the formed electroluminescent element opposing the substrate such that each optical spacer directly contacts the electroluminescent element, wherein in at least two of the sub-pixels, a corresponding one of the optical spacers is between the electroluminescent element and a corresponding one of the partially reflective layers to form at least a portion of an optical cavity of a top emitting electroluminescent device, and wherein adjacent optical spacers are spaced from each other. ### Claim 2 (depends on 1) The method of claim 1, wherein at least a portion of each of the optical spacers comprises an absorbing color filter. ### Claim 3 (depends on 1) The method of claim 1, wherein selectively thermally transferring the optical spacers comprises: providing a donor sheet comprising a base layer, a light to heat conversion layer, and one or more transfer layers; positioning the donor sheet such that the one or more transfer layers are proximate the electroluminescent element; and selectively irradiating portions of the donor sheet to thermally transfer portions of the one or more transfer layers from the donor sheet to the electroluminescent element. ### Claim 4 (depends on 3) The method of claim 3, wherein the one or more transfer layers comprise an optical spacer layer. ### Claim 5 (depends on 4) The method of claim 4, wherein the one or more transfer layers further comprise a partially reflective interface. ### Claim 6 (depends on 3) The method of claim 3, wherein the one or more transfer layers further comprise a color filter layer, and wherein selectively irradiating portions of the donor sheet comprises selectively thermally transferring a plurality of color filters to the side of the formed electroluminescent element opposing the substrate such that the partially reflective layers are between the color filters and the electroluminescent element. ### Claim 7 (depends on 1) The method of claim 1 further comprising a plurality of color filters to the side of the formed electroluminescent element opposing the substrate such that the partially reflective layers are between the color filters and the electroluminescent element. ### Claim 8 (depends on 1) The method of claim 1 further comprising forming a black matrix having a plurality of apertures on the electroluminescent element, and wherein selectively thermally transferring the optical spacers comprises, selectively thermally transferring each of the optical spacers to a corresponding one of the apertures. ### Claim 9 (depends on 8) The method of claim 8, wherein forming the black matrix comprises selectively thermally transferring the black matrix to the electroluminescent element. ### Claim 10 (depends on 1) The method of claim 1, wherein the substrate comprises a plurality of independently addressable active devices. ### Claim 11 (depends on 1) The method of claim 1, wherein a refractive index of each of the optical spacers is substantially matched to a refractive index of a surface of the electroluminescent element to which the optical spacer is transferred. ### Claim 12 (depends on 1) The method of claim 1, further comprising selectively thermally transferring the optical spacers to the electroluminescent element to form at least a portion of each optical cavity of a plurality of optical cavities, wherein at least one optical cavity of the plurality of optical cavities is tuned to pass red light, at least one optical cavity of the plurality of optical cavities is tuned to pass green light, and at least one optical cavity of the plurality of optical cavities is tuned to pass blue light. ### Claim 13 (depends on 1) The method of claim 1, further comprising selectively thermally transferring the optical spacers to the electroluminescent element to form at least a portion of each optical cavity of a plurality of optical cavities, wherein at least one optical cavity of the plurality of optical cavities is tuned to effect emission of red light, at least one optical cavity of the plurality of optical cavities is tuned to effect emission of green light, and at least one optical cavity of the plurality of optical cavities is tuned to effect emission of blue light. ### Claim 14 A method of making an electroluminescent device, the method comprising: forming an electroluminescent element on a substrate, wherein the electroluminescent element comprises a cathode; an anode; and at least a portion of a plurality of sub-pixels; and selectively thermally transferring a plurality of optical spacers and a plurality of partially reflective layers to the formed electroluminescent element such that the optical spacer directly contacts the electroluminescent element, wherein in at least two of the sub-pixels, a corresponding one of the optical spacers is between the electroluminescent element and a corresponding one of the partially reflective layer to form at least a portion of an optical cavity of a top emitting electroluminescent device; and wherein adjacent optical spacers are spaced from each other. ### Claim 15 (depends on 14) The method of claim 14, wherein at least a portion of each of the optical spacers comprises an absorbing color filter. ### Claim 16 A method of making an electroluminescent device, the method comprising: forming an electroluminescent element on a substrate, wherein the electroluminescent element comprises a cathode; an anode; and at least a portion of a plurality of sub-pixels; providing a donor sheet comprising a base layer, a light to heat conversion layer, and one or more transfer layers; positioning the donor sheet such that the one or more transfer layers are proximate the electroluminescent element; and selectively irradiating portions of the donor sheet to thermally transfer portions of the one or more transfer layers from the donor sheet to the electroluminescent element to transfer a plurality of optical spacers and a plurality of partially reflective layers to the formed electroluminescent element such that the optical spacer directly contacts the electroluminescent element, wherein in at least two of the sub-pixels, a corresponding one of the optical spacers is between the electroluminescent element and a corresponding one of the partially reflective layers to form at least a portion of an optical cavity of a top emitting electroluminescent device, and wherein adjacent optical spacers are spaced from each other. ### Claim 17 (depends on 16) The method of claim 16, wherein the one or more transfer layers comprise an optical spacer layer. ### Claim 18 (depends on 1) The method of claim 1, wherein in at least one sub-pixel, the corresponding one of the partially reflective layers directly contacts the side of the formed electroluminescent element opposing the substrate. ### Claim 19 (depends on 7) The method of claim 7, wherein a refractive index of each of the optical spacers is substantially equal to a refractive index of a surface of the electroluminescent element to which each the optical spacers are respectively transferred, and wherein a normal incidence reflectivity between the color filters and at least one of the optical spacers or the surface of the electroluminescent element is at least about ten percent, which gives rise to the partially reflective layers.