The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture.

Here I'll give the formulas used to calculate the "prescriptions" of the primary and secondary mirrors for three types of Cassegrain telescopes - the Dall-Kirkham, the classical, and the Ritchey-Chrétien.

2024年11月7日 · Ray diagram of a reflecting telescope in a Cassegrain arrangement. Draw a ray diagram to show the path of two rays, parallel to the axis, through a Cassegrain telescope, as far as the eyepiece. Answer: Step 1: Start by drawing and labelling a principal axis, a primary concave mirror and an eyepiece lens.

Some fundamentals in Cassegrain design will be discussed along with methods of optimizing existing telescopes if one chooses not to build from the ground up. To determine the correct focal plane image diameter one consideration is the field lens in your collection of eyepieces.

Ray Diagram of Cassegrain telescope. Working of reflecting type telescope – Cassegrain Telescope. In a Cassegrain telescope, light rays coming parallel to the principal axis are reflected by the concave mirror (primary objective mirror) and focused at focus point in front of the mirror.

... schematic illustration of the metasurface Cassegrain telescope based on reflective metasurface mirrors is displayed in Figure 1 a,b. A classical Cassegrain telescope consists of curved...

2020年2月29日 · The diagram below shows how a Cassegrain type telescope (such as an SCT or similar design) works to increase the effective focal length. The primary mirror of an SCT usually has a focal length only about twice its diameter.

A high-quality image over a small field is provided by a Cassegrain-type telescope — a compact telescope, Figure 9.2, e.g., Copernicus (Rogerson et al 1973), LPSP (Artzner et al 1977) and...

Cassegrain reflector, in astronomical telescopy, an arrangement of mirrors to focus incoming light at a point close to the main light-gathering mirror. The design was proposed in 1672 by French priest Laurent Cassegrain.

2023年10月21日 · The best Cassegrain telescopes are evaluated based on specific criteria, including their suitability for varied uses, performance metrics, construction quality, and their standing within the astronomy community.