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Journal of Optics

, Volume 47, Issue 3, pp 380–388 | Cite as

Experimental measurement of range of wind speed using phase plate and Shack–Hartmann wave-front sensor

  • Satya Ranjan Behera
  • B. Raghavendra Prasad
Research Article
  • 64 Downloads

Abstract

Himalayan Chandra Telescope (HCT) is a 2-m class telescope located at Indian Astronomical observatory (IAO), Hanle, Jammu and Kashmir. It is one of the world’s highest observatories and is suitable for optical and infrared regions. Atmospheric turbulence plays a vital role deciding the seeing condition of an observatory. The atmospheric turbulance at IAO is simulated using a phase plate in an laboratory adaptive optical system. Wave-fronts are generated by the rotating phase plate and sensed using a Shack–Hartmann wavefront sensor (SHWS). Cross-correlation coefficients between the first wave-front and subsequent wave-fronts reduce as speed of phase plate increases. The range of phase plate speed where wave-front can be safely reconstructed are found with corresponding wind speed. Varying exposure times over which wind speed can be measured are also calculated.

Keywords

Phase plate Shack Hartmann wavefront sensor Adaptive optics 

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Copyright information

© The Optical Society of India 2018

Authors and Affiliations

  1. 1.Indian Institute of AstrophysicsBangaloreIndia

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