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Wischnia, H. F.

Publications and source records attributed to Wischnia, H. F..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Balloon borne laser transceiver

A balloon borne laser transceiver (BBLT) which was carried to an altitude of 80,000 feet, was used to measure the turbulence effect of the atmosphere in daylight on laser beams going both up and down through the intervening atmosphere. The principles of operation of the BBLT are discussed. The instrument must acquire an up-going argon laser beam, lock onto it, and transmit back to the ground observatory a helium-neon laser beam. Questions of system operation for the down-going and the up-going beam are considered along with a servo system analysis.

Wischnia, H. F.↗
NASA NTRS1972

Active optics for space astronomy.

Discussion of the segmented and deformable active optics approaches underlying some of the modern electrooptical techniques that are to be used in the design of future generations of giant-aperture orbital space telescopes. Combinations of laser interferometry and precise servomechanisms are shown to make possible the solution of such key problems of large monolithic mirrors in orbit as weight, thermal distortion, launchability, and material stability. The applicability of these active optics approaches to future giant-aperture space astronomy systems in the 200-inch to 400-inch diameter range is reviewed.

Wischnia, H. F.↗