High-pressure discharge lamp and vehicle headlight with high-pressure discharge lamp

• US 8,310,156 B2
• Filed: 04/11/2008
• Issued: 11/13/2012
• Est. Priority Date: 04/19/2007
• Status: Expired due to Fees

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: OSRAM Licht AG (Ams-Osram AG)
• Inventors: Grundmann, Dirk
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): Breval, Elmito
• Application Number:
  US12/532,163
• Publication Number:
  US 20100141137A1
• Time in Patent Office: 1,677 Days
• Field of Search: 313623-625, 313/493, 313/318.12, 313/570, 313/578, 313631-637, 313/640, 313/642
• US Class Current: 313/570
• CPC Class Codes: H01J 61/125 having an halogenide as principal component
• CPC Class Codes: H01J 61/827 Metal halide arc lamps

Abstract

A high-pressure discharge lamp may include a discharge vessel which is sealed in a gas-tight manner and in which electrodes and an ionizable fill for generating a gas discharge are enclosed, the ionizable fill being in the form of a mercury-free fill which includes xenon and halides of the metals sodium, scandium, zinc and indium, wherein the weight ratio of the halides of zinc and indium is in the range of from 20 to 100, and wherein the coldfilling pressure of xenon is in the range of from 1.3 megapascal to 1.8 megapascal.

Claims

1. A high-pressure discharge lamp, comprising:

a discharge vessel made from quartz glass which is sealed in a gas-tight manner and in which electrodes and an ionizable fill for generating a gas discharge are enclosed, the ionizable fill being in the form of a mercury-free fill which comprises xenon and halides of the metals sodium, scandium, zinc and indium,

wherein the weight ratio of the halides of zinc and indium is in the range of from 20 to 100,

wherein the weight proportion of the halides of zinc is in the range of from 0.88 microgram to 2.67 micrograms per 1 mm³ of discharge vessel volume, and the weight proportion of the halide of indium is in the range of from 0.026 microgram to 0.089 microgram per 1 mm³ of discharge vessel volume,

wherein the weight proportion of the halides of sodium is in the range of from 6.6 micrograms to 13.3 micrograms per 1 mm³ of the discharge vessel volume, and the weight proportion of the halides of scandium is in the range of from 4.4 micrograms to 11.1 micrograms per 1 mm³ of the discharge vessel volume,

wherein the coldfilling pressure of xenon is in the range of from 1.3 megapascal to 1.8 megapascal, and

wherein the volume of the discharge vessel is greater than or equal to 20 mm³ and less than 23 mm³.

2. The high-pressure discharge lamp as claimed in claim 1, wherein the electrodes are arranged at a distance of less than 5 millimeters from one another.

3. The high-pressure discharge lamp as claimed in claim 1, wherein the thickness or the diameter of the electrodes is in the range of from 0.27 millimeter to 0.36 millimeter.

4. The high-pressure discharge lamp as claimed in claim 1, wherein the electrodes are each connected to a molybdenum foil embedded in the material of the discharge vessel, and the smallest distance between the respective molybdenum foil and that end of the electrode connected thereto which protrudes into the interior of the discharge vessel is at least 5.5 millimeters.

5. A vehicle headlight, comprising:

a high-pressure discharge lamp, the high-pressure discharge lamp comprising;

a discharge vessel made from quartz glass which is sealed in a gas-tight manner and in which electrodes and an ionizable fill for generating a gas discharge are enclosed, the ionizable fill being in the form of a mercury-free fill which comprises xenon and halides of the metals sodium, scandium, zinc and indium, wherein the weight ratio of the halides of zinc and indium is in the range of from 20 to 100, wherein the weight proportion of the halides of zinc is in the range of from 0.88 microgram to 2.67 micrograms per 1 mm³ of discharge vessel volume, and the weight proportion of the halide of indium is in the range of from 0.026 microgram to 0.089 microgram per 1 mm³ of discharge vessel volume, wherein the weight proportion of the halides of sodium is in the range of from 6.6 micrograms to 13.3 micrograms per 1 mm³ of the discharge vessel volume, and the weight proportion of the halides of scandium is in the range of from 4.4 micrograms to 11.1 micrograms per 1 mm³ of the discharge vessel volume, wherein the coldfilling pressure of xenon is in the range of from 1.3 megapascal to 1.8 megapascal, and wherein the volume of the discharge vessel is greater than or equal to 20 mm³ and less than 23 mm³.