Fabry-Perot interferometers as narrow band optical filters.

We have constructed solid Fabry-Perot narrow-band filters that can be used in systems having one arc second or better resolution. Our filters operate at H-alpha, have a three-inch aperture, and typical transmission of 70 per cent. However, the same technology can be applied to construction of filters as narrow as 0.05 A at any wavelength from 4200 to 11000 A.