# US 2008/0185953 A1 · Cathodoluminescent Phosphor Lamp > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185953 A1 - Document ID: US20080185953A1 - Status: Published application - Kind: A1 - Application number: 11/969,831 - Filed: 2008-01-04 - Published: 2008-08-07 - Earliest claimed: 2007-02-05 - Assignees: Vu1 Corporation - Inventors: Charles E. Hunt; Barnard K. Vancil; Richard N. Herring; Richard Gale Sellers - Web page: https://patentgrep.com/patent/US20080185953A1 ## CPC - H01J 9/244: {specially adapted for cathode ray tubes (H01J9/241, H01J9/26 take precedence)} - H01J 61/56: One or more circuit elements structurally associated with the lamp - H01J 63/06: Lamps with luminescent screen excited by the ray or stream - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract A light emitting device has a cathode-ray tube and power supply. The cathode-ray tube in an embodiment is optimized for emitting a broad electron beam, in one variation a dome-shaped diffusing grid is used to spread the beam. In another embodiment, the device has a base adapted for attachment to a standard lighting fixture. ## Claims ### Claim 1 A light emitting device, comprising: a glass envelope with a front surface; a cathodoluminescent (CL) phosphor coating applied to the interior of the front surface, and having a conductive layer adjacent thereto; a conductive coating within the glass envelope and contacting the CL phosphor and at least part of the internal surface of the glass envelope; a electron gun assembly further comprising: an emissive surface selected from the group consisting of a thermionic emissive surface and a cold cathode, and at least one grid; a base assembly suitable for coupling with a standard lighting fixture; and a power supply coupled to receive power from the base assembly and wherein the power supply provides a voltage between the emissive surface of the electron gun and the CL phosphor, and a voltage between the emissive surface of the electron gun and the at least one grid; wherein the at least one power supply signal causes electrons to be emitted from the electron gun assembly towards the CL phosphor such that the CL phosphor luminesces and light is emitted through the front surface. ### Claim 2 (depends on 1) The light emitting device of claim 1, the electron gun assembly comprising a glass pump stem, and the emissive surface is of the direct-heated cathode type. ### Claim 3 (depends on 1) The light emitting device of claim 1, the grid of the electron gun assembly being an extraction grid, and the electron gun assembly further comprising a diffusing grid having dome shape. ### Claim 4 (depends on 1) The light emitting device of claim 1, wherein the power supply provides a voltage to the emissive surface of the electron gun that is negative with respect to ground. ### Claim 5 (depends on 1) The light emitting device of claim 1, wherein the conductive coating is a reflective, conductive, metal. ### Claim 6 (depends on 5) The light emitting device of claim 5, wherein the conductive coating comprises metallic aluminum and is less than 0.09 micron thick in areas adjacent to the CL phosphor. ### Claim 7 (depends on 1) The light emitting device of claim 1, wherein the emissive surface is a thermionic emissive surface in the form of a disk attached to a heater, and wherein the power supply provides electrical power to heat the heater. ### Claim 8 (depends on 1) The light emitting device of claim 1, wherein the emissive surface is a directly heated filament. ### Claim 9 (depends on 1) The light emitting device of claim 1 wherein the conductive coating is a transparent conductive coating disposed between the cathodoluminescent phosphor and the internal surface of the envelope. ### Claim 10 (depends on 1) The light emitting device of claim 1 wherein the cathodoluminescent phosphor coating is densified after deposition. ### Claim 11 (depends on 1) The light emitting device of claim 1 wherein the cathodoluminescent phosphor coating is less than twenty microns thick. ### Claim 12 A light emitting device, comprising: a glass envelope with a front surface; a cathodoluminescent (CL) phosphor coating applied to the interior of the front surface; a conductive coating within the glass envelope and covering the CL phosphor and at least part of the internal surface of the glass envelope not coated by the CL phosphor; an electron gun assembly; a base assembly for coupling with a lighting fixture; and a power supply receiving power from the base assembly and generating at least one power signal for powering the electron gun assembly for applying an acceleration potential between the electron gun and the CL phosphor; wherein at least one power signal causes electrons to be emitted from the cathode assembly towards the CL phosphor such that the CL phosphor luminesces and light is emitted through the front surface. ### Claim 13 A method for fabricating a light emitting device, comprising: forming a glass envelope assembly, comprising: molding a glass envelope to have a front surface; depositing a CL phosphor on the inside of the front surface; depositing a conductive coating contacting the CL phosphor and at least part of the internal surface of the glass; fabricating an electron gun assembly, comprising: molding a glass pump stem to include one or more electrical feedthroughs and a vacuum tubulation; fabricating an electron gun having a dome-shaped diffusing grid, an extraction grid, and a cathode; attaching the electron gun to a first end of the glass pump stem, at least one of the electrical feedthroughs connecting to the gun; forming a glass assembly, comprising: inserting the gun end of the thermionic cathode assembly into the glass envelope and sealing the glass envelope to the glass pump stem; evacuating the glass envelope through the vacuum tubulation; sealing the vacuum in the glass envelope by pinch sealing the tubulation at a pinch point; fabricating a base assembly, comprising: forming a shell with a first contact area, the shell being shaped to couple with a lighting fixture and forming an electrical connection with a first contact point of the lighting fixture; adding at least one second contact area electrically insulated from the shell, the contact area coupling with a second connection point of the lighting fixture; inserting an AC level circuit into the shell, the circuit being electrically connected to the shell and the second contact area; inserting at least one high-voltage circuit into the shell, the high voltage circuit being insulated from the shell, the second contact area and the AC level circuit except for a desired connection to the AC circuit, the high-voltage circuit having at least three signal wires; and forming the light emitting device by attaching the glass assembly to the base assembly, connecting the at least three signal wires to the electrical feedthroughs and securing the base assembly to the glass assembly using an appropriate means. ### Claim 14 (depends on 13) The method of claim 13 further comprising densifying the CL phosphor. ### Claim 15 (depends on 13) The method of claim 13 wherein the CL phosphor is deposited by screen printing. ### Claim 16 (depends on 13) The method of claim 13, wherein depositing the CL phosphor is performed before depositing a conductive coating, wherein the conductive coating is a coating of reflective metal, and further comprising lacquering the CL phosphor before deposition of the conductive coating. ### Claim 17 (depends on 16) The method of claim 16 wherein the CL phosphor is less than twenty microns thick and the conductive coating comprises aluminum less than nine hunderedths of a micron thick. ### Claim 18 (depends on 17) The method of claim 17, further comprising baking the lacquering in an oxygen-free environment prior to depositing the conductive coating. ### Claim 19 (depends on 17) The method of claim 17 wherein the cathode comprises a thermionic emissive material coupled electrically and thermally to a heater. ### Claim 20 (depends on 17) The method of claim 17 wherein the cathode comprises a thermionic emissive material electrically isolated from a heater. ### Claim 21 A light emitting device comprising: an electron gun optimized for providing an unfocused source of electrons, the electron gun further comprising an emissive surface, an extraction grid, and a dome-shaped diffusing grid; an evacuated envelope having a face, the face of the envelope having a phosphor coating on an inner surface of the face, the phosphor coating having a reflective conductive coating on an inner surface thereof, the phosphor coating and reflective conductive coating together forming an anode; a power supply for providing an acceleration potential between the emissive surface of the electron gun and the anode, such that the anode is positive with respect to the cathode, and for providing a potential between the extraction grid and the emissive surface of the electron gun such that the extraction grid is positive with respect to the emissive surface; and coupling apparatus for providing power from an external AC source to the power supply. ### Claim 22 (depends on 21) The light emitting device of claim 21, wherein the diffusing grid further comprises a metallic conductive mesh attached to a metallic conductive tubular diffusing grid support, and wherein the acceleration potential is greater than five kilovolts. ### Claim 23 (depends on 22) The light emitting device of claim 22, wherein the diffusing grid is welded to the tubular diffusing grid support, and wherein the diffusing grid is formed into a dome by inserting a mandrel through the tubular diffusing grid support.