LOW-PRESSURE DISCHARGE LAMP HAVING AN ENVELOPE ENCOMPASSING THE DISCHARGE SPACE AND CONSISTING INTER ALIA OF A SUPPORT

• US 3,649,864 A
• Filed: 09/16/1969
• Issued: 03/14/1972
• Est. Priority Date: 09/19/1968
• Status: Expired due to Term

• Current Assignee: Petrus Johannes Marie Willemsen
• Original Assignee: Petrus Johannes Marie Willemsen
• Inventors: Willemsen, Petrus Johannes Marie
• Primary Examiner(s): Hossfeld, Raymond F.
• Application Number:
  US04/858,289
• Time in Patent Office: 910 Days
• Field of Search: 313/201,210,217,220,109,109.5,112,221
• US Class Current: 313/622
• CPC Class Codes: H01J 61/56 One or more circuit elements structurally associated with the lamp

Abstract

A low-pressure glow discharge lamp having an envelope encompassing the discharge space formed from a ceramic dielectric material which is coated by layers of electrical conducting material to function as a self-ballasting capacitor for stabilizing the electric discharge in the lamp.

Claims

1. A discharge lamp comprising an oblong envelope forming a discharge space, end parts for hermetically sealing said envelope, said envelope essentially consisting of a transparent ceramic dielectric material having a coefficient of expansion substantially equal to that of said end parts, an ionizing gas filling said discharge space, electrodes for producing a gaseous discharge within said envelope, electrically conductive transparent layers on opposite sides of said envelope in confronting relationship, the inner conduction layer functioning as one of said electrodes in said discharge space, the inner and outer conducting layers and said dielectric material forming a ballasting capacitor in series with said discharge space for stabilizing said gaseous discharge within said lamp, an electrode functioning as the second of said electrodes in said discharge space, and terminal means for providing current to said lamp.

2. A discharge lamp as claimed in claim 1 wherein said second electrode is positioned along the longitudinal axis of said lamp.

3. A discharge lamp as claimed in claim 1 wherein said transparent ceramic dielectric material essentially consists of barium titanate and said electrically conducting material essentially consists of tin oxide.

4. A discharge lamp as claimed in claim 1 further comprising a lacquer coating of a transparent insulating material for said electrically conducting material.

5. A discharge lamp as claimed in claim 4 wherein said lacquer coating partly consists of a reflective material.

6. A discharge lamp as claimed in claim 1 wherein said end parts essentially consist of glass, one of said end parts being in the form of a hemispherical bead and the other having an arclike profile.

7. A discharge lamp as claimed in claim 1 wherein said end parts are flat thin walled portions positioned transverse to the longitudinal axis of said lamp.

8. A discharge lamp as claimed in claim 1 wherein said internal electrically conductive, transparent layer has a low work function.

9. A discharge lamp comprising an oblong envelope forming a discharge space, end parts for hermetically sealing said envelope, said envelope essentially consisting of a transparent ceramic dielectric material having a coefficient of expansion substantially equal to that of said end parts, an ionizing gas filling said discharge space, at least one pair of electrically conductive transparent layers spaced apart on opposite sides of said envelope in confronting relationships, the internal conducting layer functioning as an electrode for producing a gaseous discharge, the inner and outer conducting layers and said dielectric material forming a ballasting capacitor in series with said discharge space to stabilize said gaseous discharge within said lamp, and terminal means connected to said external conducting layers for providing current to said lamp.

10. A discharge lamp as claimed in claim 9 wherein said electrically conductive transparent layErs have a semicylindrical shape.