Abstract
The Fery spectrograph uses a single quartz optical unit that combines the characteristics of prism, mirror, and lenses. Hence, it presents its greatest advantage in the ultraviolet, where loss of light is minimized by the small number of air-quartz surfaces and the rather small thickness of optical material used. This very high efficient spectrograph, combined with modern detectors, results in a very powerful instrument for Astronomy. A few attractive astronomical applications are described, as well as how to its vertical astigmatism.
