Abstract: A double reflector is described which comprises two spaced apart primary mirrors oriented toward a common focus. The optical system further comprises two separate secondary deflector mirrors as well as tertiary deflector mirrors for beam concentration on a common focus. Both the primary mirrors and the secondary deflector mirrors are so-called off-axis reflectors, i.e. their surface represent surface sectors of a hypothetical big aspherical mirror body. As surface sectors of a hypothetical big hyperbolic mirror, the primary mirrors are inclined at an angle with respect to the common optical axis and each disposed at a given spacing from the same in such manner that the inner marginal rays of the incident radiation which are closest to the optical axis, will converge.

Abstract: A double reflector system is described which comprises two spaced apart primary mirrors oriented toward a common focus. The optical system further comprises two separate secondary deflector mirrors as well as tertiary deflector mirrors for beam concentration on a common focus. The optical system is housed in an elongate casing having coaxial bearing support cylinders at its opposite ends which define an axis of elevation, and the casing is hydrostatically supported in part on a circular tray which is in turn hydrostatically and rotatably supported upon a stationary bed. A support ring is disposed concentrically about the tray, and the support ring includes bushings which receive the bearing cylinders of the casing and thus also support in part the weight of the casing. The support ring and the tray are independently rotatable in a horizontal plane, and the casing is rotatable by a separate drive about the axis of elevation.

Abstract: A reflecting telescope is described, in which the surface of the primary mirror is in the form of a pitch circular surface of a hypothetical, rotationally symmetrical large mirror. The optical axis parallel to the incident optical path and the focal point of the primary mirror and the large mirror are consequently identical. The primary mirror or pitch circular surface are located alongside the optical axis, so that all the optical and mechanical aids to be arranged in the vicinity of the focal point can be located outside the light incidence area and the reflection field, without optical correcting means being required.

Abstract: A main mirror for a reflecting telescope comprises plurality of individual polygonal reflecting elements (1 to 11) and positioning and adjusting elements (12) connected thereto. Prior art main mirrors of this type have a poor capacity for transmitting ponint images and for modulation and are unsuitable for use in the infrared region, because the positioning and adjustment elements, in particular the measurement sensors arranged in the region of the separating lignes between the individual polygonal reflecting elements (1 to 11) emit interfering thermal radiation. Furthermore, the polygonal reflecting elements (1 to 11) of prior art main mirrors (20) are expensive to manufacture.

Abstract: Reflector telescope, consisting of a tube (2) disposed in a spherical casing (1) and an outer framework (4) in which the spherical casing (1) is mounted. In known reflector telescopes, the tube is rotatable about its polar and declination axis, requiring two different driving systems. Moreover, access to the spherical casing is variable according to the position of said casing. These disadvantages are avoided by mounting the spherical casing (1) within the outer framework (4) to rotate about a horizontal axis (8), and by mounting said framework on a base to rotate about a vertical axis (50). Fixed and permanent access to the spherical casing (1) and therefore to the tube (2) is thus ensured, and the provision of a driving force for the spherical casing (1) is easily achieved.

Abstract: A reflecting telescope according to the invention includes a tube having an inlet and a primary mirror end. A plurality of mirror segments cooperate to form a single mirror of a single paraboloid-shaped surface by grinding the mirror segments all together in a single grinding process. This mirror is then positioned at the primary mirror end of the tube. Each of the plurality of mirror segments has a circular disk shape and is arranged in one of circular tracks, each circular track being defined by an inner circle and an outer circle with each inner and outer circle being concentric to the tube central axis. The areas free of mirror segments lie between the mirror segments of circular disk shape and an innermost area free of mirror segments lies within an innermost circular track. Bearings are positioned about each of the mirror segments at the areas free of mirror segments for adjustment of the mirror segments.