Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
Email Facebook Twitter Google+ LinkedIn Comments

  • Catch a Wave:

Photonics Spectra
Mar 1999
Wavefront Sensors Gauge Optical System Performance

Joseph M. Geary, Center for Applied Optics, University of Alabama-Huntsville.

Light travels in straight lines, as evidenced by shadow-casting phenomenon, and the pinhole camera. The pinhole camera also helps define a "ray" of light. A point source emits light rays in all directions. A group of these rays would have a certain optical path length: length ? refractive index. The optical path length is a radius in this case, and the ray tips lie on the surface of a sphere whose center is the point source.
This surface is a basic example of what is called a wavefront. (Rays and their associated wavefronts are always orthogonal to one another.) Examining that wavefront can tell us much about any optics or an optical system that is between the light source and the measured wavefront. For example, NASA used several types of wavefront sensors to test the Hubble Space Telescope and its associated instruments.

Terms & Conditions Privacy Policy About Us Contact Us
back to top

Facebook Twitter Instagram LinkedIn YouTube RSS
©2016 Photonics Media
x Subscribe to Photonics Spectra magazine - FREE!