Korsch telescope

When Korsch telescope reflector telescopes are called derived from the Cassegrain telescope and differ from them by a third active optical element ( mirror ). As a major advantage to a flat field and less scattered light results in the imaging plane. It consists of an ellipsoidal primary mirror, a hyperbolic secondary mirror, an ellipsoidal Tertärspiegel and, depending on the severity, of one or more planning auxiliary mirrors. The major advantages of this optical structure in the image quality to be bought by a high expense in the calculation and production of aspheric mirror and by very small adjustment tolerances; Furthermore, the results due to the required deflection mirror a perforated annular image.

The construction is based on a design by the American G. Dietrich Korsch and in 1978 was patented.

The most common Korsch telescope is the planned James Webb Space Telescope. Similarly, the proposed Euclid mission of ESA and the 2- m telescope of the planned satellite SNAP is based on a Korsch design. In addition, some existing and planned Earth observation satellites ( MTG, EnMAP, Persona ) are based on dreispiegeligen constructions on Korsch base in offset arrangement of the optical axis ( Schiefspiegler ). The Kodak company also offers the telescope as a finished assembly, which is sometimes also used in a modified series of Earth observation satellites, such as the OrbView, IKONOS and GeoEye.

486332
de