The wedge prism was custom made by Sinoptix based in Shanghai, China and has a 7 degree angle, and the faces are polished flat to within 1/4 wavelength of visible light, as measured by an interferogram. The glass is flint type with a low Abbe number giving a large change in refractive index as a function of wavelength, dn/dlambda, to maximally disperse the wavelengths of optical light. The prism, its design, and its mounting over the telescope are shown in the following images. Zemax simulations of the combined prism and telescopes (shown below).
