This telescope is a Schmidt Cassegrain style of scope, which is a style of reflector scope rather than a refractor. It uses mirrors instead of lenses to capture light, so it doesn't suffer from the phenomenon of chromatic aberration in the way that refractors do.

The front of this telescope holds a corrector plate, with the secondary mirror in the middle. At the rear, the primary mirror is held in a carrier which moves along the length of the tube to focus the image. The light cone is directed from the rear primary mirror back along the length of the tube to the front-mounted secondary mirror, and then finally out the back of the tube through a corrector lens that flattens the focal plane, reducing the effect of field curvature. This multiple mirror system results in a folded optical path, which allows for a long focal length (in this case >2000mm) in a relatively short tube.

More information about this telescope can be found on the Celestron website, and for anyone who really wants to understand the optical details of this type of scope you can download a PDF document from here.