Principal focus type refracting-reflecting optical system

Abstract

The invention relates to a principal focus type refracting-reflecting optical system having an aperture of above 1m, a viewing field of above 3 degrees and a flat image surface, which is convenient for being externally connected with a focal plane photoelectric receiving device and can be used for ground-based observation. The principal focus type refracting-reflecting optical system comprises a paraboloidal primary lens (1), a correction group (2) and a focal plane shutter (6), wherein the correction group comprises four correction lenses which are a first lens (2) having positive focal power and being a meniscus lens with a convex surface facing the primary lens, a second lens (3) having negative focal power and being a meniscus lens with a convex surface facing the primary lens, a third lens (4) having negative focal power and being a meniscus lens with a convex surface facing the primary lens and a fourth lens (5) having positive focal power respectively. In the correction group (1), only the concave surface of the first lens (2) is a paraboloid, the concave surfaces of other lenses are spherical surfaces.

Description

technical field [0001] The invention relates to the field of optical systems, in particular to a prime-focus type catadioptric optical telescope, which can be applied to a large field-of-view field-based telescope with an aperture exceeding 1m. Background technique [0002] The flat-field telescope with large aperture and large field of view is of great significance in astronomical observation and space debris monitoring. Large aperture means stronger light-gathering ability, thus detecting weaker magnitudes; large field of view means larger single-frame field of view, which can search the sky faster; flat field means convenient configuration Focal plane photodetection device. Large-aperture and large-field-of-view flat-field telescopes are playing an increasingly important role in sky surveys and space debris monitoring. [0003] The traditional large-aperture telescope must use a reflective primary mirror, and the characteristics of the reflective optical system limit th...

AI Technical Summary

Problems solved by technology

[0003] The traditional large-aperture telescope must use a reflective primary mirror, and the characteristics of the reflective optical system limit the increase of the field of view. Although there are several special forms that can achieve a larger field of view, such as the Schmidt telescope and the three-dimensional Anti-even four anti-telescopes, but because the Schmidt correction plate is difficult to manufacture and process, and the three-anti or four-anti-telescopes have a large block, so their serious defects have led to seldom used in practice

The prime-focus catadioptric optical system can theoretically achieve a larger field of view, but the correction group is more complicated, requiring the use of various grades of optical glass for achromatization, and the use of high-order aspheric surfaces to correct aberrations. For large-diameter optical lenses In other words, many grades of optical glass are difficult to refine, and there are certain difficulties in the processing and testing of large-aperture and high-order aspheric surfaces. Therefore, it is necessary to develop a prime-focus optical system that is convenient for engineering realization.

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