Accession Number : ADD007209

Title :   Gas Laser Aerodynamic Window.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Stewart,Charles C ; Avidor,Joel M ; Pugh,Evan R ; Lothrop,John W

Report Date : 06 May 1980

Pagination or Media Count : 8

Abstract : The aerodynamic window is formed of a contiguous pair of gas jet streams driven at subsonic velocity across the entire cross-sectional area of an annular laser beam. One of the jet streams has a shear interface with the interior gas of the laser and has its index of refraction matched to it. The other interfaces with the outside air into which the beam passes and it too has a refraction index matched to the air. Matching of the indices minimizes optical distortion of the beam at the shear interfaces. Distortion produced at the boundary layer of the contiguous jet streams is minimized by equalizing their velocities. To maintain a desired laser cavity pressure, the jet streams are permitted to bend responsively to the pressure differential. The degree of the bending is controlled to reduce window gas consumption. (Author)

Descriptors :   *Patents, *Windows, *Laser materials, Jet flow, Refractive index, Beams(Radiation), Shear properties, Pressure gradients, Boundary layer, Subsonic characteristics

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE