Accession Number : ADD012265

Title :   Method and Apparatus for High Speed, Sustained Recording of Infrared Laser Beam Patterns.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Geary,Joseph M ; Vunck,Darius S ; Duneman,Dennis C ; Sessions,Ronald L ; Moeller,Charles E

Report Date : 18 Mar 1986

Pagination or Media Count : 5

Abstract : This patent discloses a method of photographically recording at high speed the far field pattern of a high energy infrared laser beam over a selected period of time for providing rapid repetitive samples of information on beam parameters such as far field beam intensity, jitter, and absolute beam size and power. A sample from a high energy infrared laser beam is directed into an enclosure that is light tight to visible radiation and contains an operating lensless movie camera loaded with suitable movie film. The infrared beam is focused on the film plane of the camera so that consecutive frames of the film are irradiated by the infrared beam each time the camera shutter is open. The period of irradiation is of sufficient duration to sensitize the film to visible radiation in the areas where the infrared radiation impinges on the film. The position of the camera shutter is detected and an electrical trigger signal generated just before the shutter is closed for each frame. The trigger signal is applied to appropriate circuitry which actuates a light source to generate a pulse of visible light that irradiates the film plane of the camera near the end of each shutter movement to expose each frame of the film. The exposed film strip is developed to provide a continuous record of the infrared laser beam characteristics over the selected period of time.

Descriptors :   *PATENTS, *PHOTOGRAPHIC ANALYSIS, *HIGH SPEED PHOTOGRAPHY, *LASER BEAMS, SIZES(DIMENSIONS), CAMERA SHUTTERS, TRIGGER CIRCUITS, INFRARED RADIATION, INFRARED FILM

Subject Categories : Lasers and Masers
      Photography
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE