Mechanically sealed tube for laser sustained plasma lamp and production method for same

• US 10,109,473 B1
• Filed: 01/26/2018
• Issued: 10/23/2018
• Est. Priority Date: 01/26/2018
• Status: Active Grant

• Current Assignee: Excelitas Technologies Corporation (Excelitas Technologies Holdings LLC)
• Original Assignee: Excelitas Technologies Corporation (Excelitas Technologies Holdings LLC)
• Inventors: Blondia, Rudi, Doughty, Douglas A., Kiss, John, Roberts, Roy D.
• Primary Examiner(s): Williams, Joseph L
• Assistant Examiner(s): Diaz, Jose M
• Application Number:
  US15/880,754
• Time in Patent Office: 270 Days
• CPC Class Codes: H01J 61/025 Associated optical elements
• CPC Class Codes: H01J 61/06 Main electrodes
• CPC Class Codes: H01J 61/16 having helium, argon, neon, krypton, or xenon as the principle constituent
• CPC Class Codes: H01J 61/361 Seals between parts of vessel
• CPC Class Codes: H01J 61/54 Igniting arrangements, e.g. promoting ionisation for starting
• CPC Class Codes: H01J 65/042 by an external electromagnetic field
• CPC Class Codes: H01J 9/266 specially adapted for gas-discharge lamps
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence

Abstract

A laser sustained plasma lamp includes a mechanically sealed pressurized chamber assembly (330) configured to contain an ionizable material. The chamber assembly is bounded by a chamber tube (310), an ingress sapphire window (340), a first metal seal ring (320) configured to seal against the chamber tube ingress end and the ingress sapphire window, an egress sapphire window (342), and a second metal seal ring (322) configured to seal against the chamber tube egress end and the egress sapphire window. A mechanical clamping structure (350, 355) external to the chamber assembly is configured to clamp across at least a portion of the ingress sapphire window and the egress sapphire window. The ingress sapphire window and the egress sapphire window are not connected to the chamber tube via welding and/or brazing.

Claims

1. A laser sustained plasma lamp (300), comprising:

a mechanically sealed pressurized chamber assembly (330) configured to contain an ionizable material, the chamber assembly comprising and bounded by;

a chamber tube (310) comprising an ingress end and an egress end;

an ingress sapphire window (340) disposed at the chamber tube ingress end;

a first metal seal ring (320) configured to seal against the chamber tube ingress end and the ingress sapphire window;

an egress sapphire window (342) disposed at the chamber tube egress end; and

a second metal seal ring (322) configured to seal against the chamber tube egress end and the egress sapphire window; and

a mechanical clamping structure (350, 355) external to the chamber assembly configured to clamp across at least a portion of the ingress sapphire window and the egress sapphire window,

wherein the ingress sapphire window and the egress sapphire window are not connected to the chamber tube via welding and/or brazing.

2. The lamp of claim 1, wherein the mechanical clamping structure comprises a sleeve comprising an interior surface comporting to an exterior surface of the chamber tube.

3. The lamp of claim 2, wherein the sleeve further comprises:

a first sleeve portion (350) disposed at the chamber tube ingress end; and

a second sleeve portion (355) disposed at the chamber tube egress end.

4. The lamp of claim 3, wherein the first sleeve portion is TIG welded to the second sleeve portion.

5. The lamp of claim 3, wherein the first sleeve portion is brazed to the second sleeve portion.

6. The lamp of claim 1, wherein the ingress window and/or the egress window are precision finished, ground, and polished.

7. The lamp of claim 1, wherein the mechanically sealed pressurized chamber is substantially cylindrical in shape.

8. The lamp of claim 1, wherein the chamber tube comprises sapphire.

9. The lamp of claim 1, wherein the first metal seal ring and/or the second metal seal ring comprises a C-shape.

10. The lamp of claim 1, wherein at least a portion of the chamber tube and/or a portion of the ingress and egress windows configured to contact the first and/or second metal seal ring is plated with a soft metal.

11. The lamp of claim 1, wherein the first metal seal ring and/or the second metal seal ring is coated with a soft metal.

12. A method for manufacturing a laser sustained plasma lamp, comprising the steps of:

positioning within a sleeve assembly comprising a first sleeve portion and a second sleeve portion a chamber assembly comprising a chamber tube, a first chamber window, a first chamber seal, a second chamber window, and a second chamber seal;

securing the sleeve assembly and the chamber assembly in a jig within a tooling chamber;

sealing the tooling chamber;

filling the tooling chamber with a pressurized ionizable medium;

compressing the first window, the first seal, the chamber tube, the second seal, and the second window against the jig to seal the chamber assembly; and

evacuating the tooling chamber.

13. The method of claim 12, further comprising the step of welding the first sleeve portion and a second sleeve portion together.

14. The method of claim 13, wherein the welding is TIG welding.

15. The method of claim 12, further comprising the step of brazing the first sleeve portion and a second sleeve portion together.

16. A laser sustained plasma lamp, comprising:

a mechanically sealed pressurized chamber assembly configured to contain an ionizable material, the chamber assembly comprising and bounded by;

a chamber tube comprising an open ingress end and a closed end;

a sapphire window disposed at the chamber tube open end;

a metal seal ring configured to seal against the chamber tube open end and the sapphire window;

a mechanical clamping structure external to the chamber assembly configured to clamp across at least a portion of the sapphire window and the chamber tube closed end

wherein the sapphire window is not connected to the chamber tube via welding and/or brazing.