Ultraviolet radiation source

• US 3,956,655 A
• Filed: 12/23/1974
• Issued: 05/11/1976
• Est. Priority Date: 12/23/1974
• Status: Expired due to Term

• Current Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Pevo, Jack L.
• Primary Examiner(s): Kominski, John
• Application Number:
  US05/535,628
• Time in Patent Office: 505 Days
• Field of Search: 313/110, 313/112, 313/116, 313/117, 350/1, 350/2, 220/2.1 R, 220/2.2
• US Class Current: 313/112
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: H01J 61/33 Special shape of cross-section, e.g. for producing cool spot

Abstract

A gas discharge tube for efficiently generating ultraviolet radiation, which is transmitted through a portion of the tube envelope for spectrographic use. The tube is filled with hydrogen or deuterium at a low pressure. The tube envelope is formed of a glass envelope which has a cylindrical envelope portion about the anode and cathode discharge path which is circumferentially thinned to from about 0.005 inch to 0.020 inch.

Claims

1. A low pressure gas filled discharge device for generating ultraviolet radiation for spectrographic analysis, comprising a hermetically sealed envelope, with a selected ultraviolet radiation emitting gas at low pressure filling the envelope, a filamentary heated cathode and an anode spaced from the cathode disposed within the envelope, with baffling means disposed about and between the cathode and anode for constricting the discharge therebetween to excite the fill gas and generate the desired ultraviolet radiation, and wherein the hermetically sealed envelope comprises a generally cylindrical ultraviolet transmissive vitreous envelope portion having a closed top envelope portion, and a vitreous glass base member sealed to the bottom of the cylindrical envelope portion, with electrical lead-ins sealed through the base member and operatively connected to the cathode, anode, and baffle means, with the cylindrical envelope being relatively thin and having an even thinner circumferential wall highly ultraviolet transmissive portion, spaced about the anode and cathode discharge producing portions of the tube, wherein the said even thinner circumferential wall portion is from about 0.005 inch to about 0.020 inch.

2. The discharge device of claim 1, wherein the fill gas is hydrogen or deuterium.

3. The discharge device of claim 1, wherein the fill gas is at about 16 Torr, and the power input is less than about 250 watts.

4. The discharge device of claim 1, wherein the wall thickness of the cylindrical envelope portion is about 0.030 inch thick and the thin wall portion is about 0.010 inch.

5. The discharge device of claim 1, wherein the remainder of the cylindrical wall portion of the envelope is at least about three times the thickness of the thin wall portion.