In observations of celestial bodies from ground telescopes, the signal is faint and surrounded with unwanted optical noise from the atmosphere. The OH radicals present in the atmosphere emit light in hundreds of narrow lines that dominate the inter-line sky emission by many orders of magnitude. The multi-spectral rejection filter based on Ondax holographic technology discriminates the narrow spectral features of the OH emission lines from the atmosphere which increases the image sharpness by increasing the signal to noise ratio. A one inch (25mm) aperture rejection filter with 10 lines between 1505nm and 1580nm has been fabricated and tested by Caltech Astronomers at the 200 inch Hale Telescope at the Palomar Observatory in Southern California.
For more information on our Astronomy multi-line filters, please e-mail us or contact us directly at (626) 357-9600.
| Fig: Experimental results with a 10 line rejection holographic filter with 0.8nm FWHM bandwidth. Transmission between the lines > 80% across the one inch aperture.
For more information visit: http://www.astro.caltech.edu
|
|
