SHS

(Spectrohelioscope)

The diagram shows the working principle of a SHS (Spectrohelioscope). The purpose is to observe the Sun in various wavelengths in two dimensions. The Sun is focused on slit #1. That narrow beam of light is aligned with the groves of the diffraction reflexion grating. The latter optical device linearly disperse the solar light into its colour components, a spectrum. In solar business we normally wish to look at Ha. By tilting the grating we choose any colour in the solar spectrum. At the plane of slit #2 where the spectrum is focused, we fine tune the wavelength of interest. With the eyepiece it is visually accessible. When the slits (or in my case wiggling the prisms) move back and forth at a fast pace, we synthesize a picture using the colour of our choise.

The picture shows the general problem with optics. A lot of mechanics involved. Although not the neatest design it has produced  some results.