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- Path: sparky!uunet!noc.near.net!mars.caps.maine.edu!maine.maine.edu!hassler
- Organization: University of Maine System
- Date: Thursday, 27 Aug 1992 13:37:19 EDT
- From: John Hassler <HASSLER@MAINE.MAINE.EDU>
- Message-ID: <92240.133719HASSLER@MAINE.MAINE.EDU>
- Newsgroups: sci.electronics
- Subject: Re: Old laser rejuvenation
- References: <massoud.57@chemteca.sdsu.edu> <1992Aug26.194917.734@cs.ucf.edu>
- Lines: 39
-
- In article <1992Aug26.194917.734@cs.ucf.edu>, clarke@acme.ucf.edu (Thomas
- Clarke) says:
- >
- >In article <massoud.57@chemteca.sdsu.edu> massoud@chemteca.sdsu.edu (Massoud
- >Ajami) writes:
- >> In article <1992Aug26.043710.27944@vpnet.chi.il.us> cgordon@vpnet.chi.il.us
- >(gordon hlavenka) writes:
- >>
- >>
- >> >I have an _ancient_ laser which almost works. It's a HeNe laser,
- >> >model 3100 from Gaertner Scientific (circa 1969). It worked for a
- >> >while, but now has developed an electrical problem.
- >>
- >>
- >> You have lost the gas. You woudln't expect helium gas stays in the
- >> tube forever?
- >>
- >About five or six years ago I saw a little article in Applied Optics
- >about rejuvenating olf HeNe tubes by putting the tube in a chamber
- >with pressurized(?) He for a day or so. The He would migrate back
- >into the tube and after a while the tube worked just like new.
- >Probably wouldn't want to overshoot though. Can pressurize it in
- >fairly quickly, but would have to wait years for too much to
- >diffuse out again !-)
- >--
- >Thomas Clarke
- >Institute for Simulation and Training, University of Central FL
- >12424 Research Parkway, Suite 300, Orlando, FL 32826
- >(407)658-5030, FAX: (407)658-5059, clarke@acme.ucf.edu
-
- Don't need to "pressurize", just need the partial pressure of He to
- be greater outside than inside of the laser tube. I did it once by
- putting the laser inside of a garbage bag and filling it with He. I put
- in more He a couple of times a day, as the bag collapsed. As I remember,
- the laser came back to life in a couple of days, and continued to work for
- at least several months.
- =======================================================================
- J. C. Hassler Dept. of Chem. Eng. U. of Maine
- ========================================================================
-