One of the mysteries of the English language finally explained.
A reflecting telescope in which light reflected from a convex secondary mirror passes through a hole in the primary mirror.
- ‘A correcting plate (a lens) was added in 1930 by the Estonian astronomer and lens-maker Bernard Schmidt, creating the Schmidt-Cassegrain telescope which minimized the spherical aberration of the Cassegrain telescope.’
- ‘In an all-reflective Cassegrain telescope (usually called a Classical Cassegrain), there is no corrector lens.’
- ‘Visitors can also see the University Observatory, which houses a 14 inch Schmidt Cassegrain telescope with a cooled CCD (Charge Couple Device) camera.’
- ‘The tube length is very long compared to a Cassegrain telescope of the same effective focal length.’
- ‘Easy portability and precision optics are hallmarks of Cassegrain telescopes, and Orion has some of the finest.’
Late 19th century: named after N. Cassegrain (1625–1712), the French astronomer who devised it.
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