# US 8,786,179 B2 · Light emitting device comprising phosphorescent materials for white light generation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,179 B2 - Document ID: US8786179B2 - Status: Granted - Kind: B2 - Application number: 13/621,739 - Filed: 2012-09-17 - Published: 2014-03-20 - Granted: 2014-07-22 - Earliest claimed: 2012-09-17 - Assignees: Universal Display Corporation - Applicants: Universal Display Corporation - Inventors: Mark E. Thompson; P. Daniel Dapkus - Web page: https://patentgrep.com/patent/US8786179B2 ## CPC - C09K 11/06: containing organic luminescent materials - C09K 2211/1007: Non-condensed systems - C09K 2211/1029: containing one nitrogen atom as the heteroatom - C09K 2211/1037: with sulfur - C09K 2211/1044: containing two nitrogen atoms as heteroatoms - C09K 2211/185: of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd - C09K 2211/188: of other metals not provided for in one of the previous groups - H10H 20/8512: {Wavelength conversion materials} - H10H 20/8513: {having two or more wavelength conversion materials} - Y02B 20/00: Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract The present invention relates to phosphors for energy downconversion of high energy light to generate a broadband light spectrum, which emit light of different emission wavelengths. ## Claims ### Claim 1 A white light emitting device comprising an emissive layer having a thickness of from about 100 microns to about 1000 microns, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation, and emits light of different emission wavelengths having lower energies than the first wavelength λ1. ### Claim 2 (depends on 1) The white light emitting device of claim 1, wherein the phosphor when excited emits white light with a quantum efficiency of at least 40%. ### Claim 3 (depends on 1) The white light emitting device of claim 1, wherein the phosphor when excited emits white light with a quantum efficiency of at least 50%. ### Claim 4 (depends on 1) The white light emitting device of claim 1, wherein the phosphor has a photoluminescent efficiency of from about 50% to about 100%. ### Claim 5 (depends on 1) The white light emitting device of claim 1, wherein the first wavelength λ1 is in the range of 300 nm and 450 nm. ### Claim 6 (depends on 1) The white light emitting device of claim 1, wherein the phosphor emits from a triplet states upon absorption of light at the first wavelength λ1. ### Claim 7 (depends on 1) The white light emitting device of claim 1, wherein the phosphor comprises two or more phosphors. ### Claim 8 (depends on 1) The white light emitting device of claim 1, wherein the phosphor comprises a first phosphor and a second phosphor. ### Claim 9 (depends on 8) The white light emitting device of claim 8, wherein the first phosphor emits light in a wavelength range of 400 nm to 540 nm. ### Claim 10 (depends on 8) The white light emitting device of claim 8, wherein the second phosphor emits light in a wavelength range of 520 nm to 700 nm. ### Claim 11 (depends on 8) The white light emitting device of claim 8, wherein the first phosphor is present in a percent weight of from 10% to 90% and the second phosphor is present in a percent weight of from 90% to 10%. ### Claim 12 (depends on 8) The white light emitting device of claim 8, wherein the phosphor further comprises a third phosphor. ### Claim 13 (depends on 12) The white light emitting device of claim 12, wherein the third phosphor emits light in a wavelength range of 500 nm to 600 nm. ### Claim 14 (depends on 1) The white light emitting device of claim 1, wherein the phosphor is dispersed at the molecular level in a solid, crystalline or microcrystalline matrix, and further wherein the matrix comprises a polymer. ### Claim 15 (depends on 1) The white light emitting device of claim 1, wherein the phosphor comprises a phosphorescent metal complex. ### Claim 16 (depends on 1) The white light emitting device of claim 1, wherein the phosphor comprises a phosphorescent organometallic iridium complex. ### Claim 17 (depends on 1) The white light emitting device of claim 1, wherein the emissive layer has an optical density of greater than 1.0 absorbance unit in a wavelength range of from 300 nm to 450 nm. ### Claim 18 A white light emitting device comprising an emissive layer, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation, and emits light of different emission wavelengths having lower energies than the first wavelength λ1, wherein the phosphor comprises a single phosphor that emits simultaneously from molecular and aggregate states. ### Claim 19 (depends on 18) The white light emitting device of claim 18, wherein the single phosphor emits light from the molecular state in a wavelength range of blue and/or green. ### Claim 20 (depends on 18) The white light emitting device of claim 18, wherein the single phosphor emits light from the aggregate state in a wavelength range of orange. ### Claim 21 A white light emitting device comprising an emissive layer, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation, and emits light of different emission wavelengths having lower energies than the first wavelength λ1, wherein the phosphor does not absorb the emitted light by the phosphor. ### Claim 22 A white light emitting device comprising an emissive layer, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation, and emits light of different emission wavelengths having lower energies than the first wavelength λ1, wherein the phosphor is dispersed at the molecular level in a solid, crystalline or microcrystalline matrix, and further wherein the phosphor is present at a concentration of less than 0.1 weight percent based on the total weight of the matrix. ### Claim 23 A white light emitting device comprising an emissive layer, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation, and emits light of different emission wavelengths having lower energies than the first wavelength λ1, wherein the phosphor comprises a phosphorescent organometallic copper complex. ### Claim 24 A white light emitting device comprising an emissive layer having a thickness of from about 100 microns to about 1000 microns, wherein the emissive layer comprises a phosphorescent phosphor for energy downconversion to generate a broadband light spectrum, wherein the phosphor absorbs light at a first wavelength λ1 of radiation from an excitation source in the blue, violet, or ultra violet region, and emits light of different emission wavelengths having lower energies than the first wavelength λ1; wherein the phosphorescent comprises a copper complex, iridium compound or mixtures thereof. ### Claim 25 A method of generating white light comprising: providing an excitation source; providing a molecular phosphorescent phosphor for absorbing a UV light source at a first wavelength λ1 of radiation; and emitting light of different emission wavelengths having lower energies than the first wavelength λ1; wherein the phosphor does not absorb the emitted light by the phosphor.