Michael L Vocaturo

US Patent:

50349520, Jul 23, 1991

Filed:

Dec 5, 1989

Appl. No.:

7/446345

Inventors:

Dennis K. Mansfield - E. Windsor NJ
Michael Vocaturo - Columbus NJ
Lawrence J. Guttadora - Iselin NJ

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

H01S 310

US Classification:

372 26

Abstract:

A Stark-tuned laser operating in the 119 micron line of CH. sub. 3 OH has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers.