CATADIOPTRIC TELESCOPE Russian patent published in 2013 - IPC G02B23/00 G02B17/08 G02B7/183 

FIELD: physics.

SUBSTANCE: device has a main spherical mirror which is rigidly fixed on a bushing with pronounced elastic lobes, a compensating element which acts as a secondary mirror and has radial adjustment gaps in pairs: reflecting lens - holder and spacer ring - holder, filled with an elastic sealing compound after adjustment, and removable three-lens isoplanatic compensator of off-axis aberrations and two-lens afocal compensator of off-axis aberrations. Adjusters of the main mirror and the compensating element are in form of two ball hinges, one of which is fixed and the other moves along an optical axis. Three braces of the fastening member of the compensating element, which lie on a circle through 120°, have a radius of curvature which is equal to the length of their chords. The compensating element consists of two lenses made from different types of glass, having in the visible spectrum quasi-close dispersion coefficients. The first lens on the beam path is a negative quasi-afocal meniscus made from glass with a high refraction index whose concave side faces the object.

EFFECT: providing diameter of the effective aperture of not less than 250 mm, high image quality in the 400-700 nm range and resistance to misalignment and temperature drop with minimum size and weight.

5 cl, 2 dwg