The Fabry Perot Etalon
Here you see the entire solid etalon.
The Muscovite mica spacer is around 10 to 30 um wide (in some designs)
and coated with a reflective material. Based on the destructive
interference of light, unwanted rays are cancelled out and desired rays are passed.
The resulting "comb" is shown as a series of light peaks with one
centered on the Ha wavelength of 656.28.
Heating the mica causes this peak to shift
from the centerline wavelength.
Muscovite Mica (bloc and cleaved) used
in rear mounted Hydrogen Alpha Filters
The purity of the mica, the amount of reflectivity
of the coatings on it, the distance between them and the temperature determine the bandpass of the filter or how much solar detail you’ll see.
The lower the bandpass the greater the disk detail and the higher the
price.
Why Ha? |
The View |
What you see |
The Chromos |
Ha Emission |
Bandwidth |
Main Designs |
Ha Components |
Rear Filters |
The Etalon |
Front Filters |
Coronado filters |
DayStar Filters |
Solar Spectrum Filters
