There are several kinds of machines referred to as spectrographs , depending on the precise nature of the waves. Henry Draper when he invented the earliest . Basic principles of a spectrograph. In other words obtain and record the spectral content of light or its . First, light travels from a telescope through a small opening in the spectrograph to a collimating mirror that lines up all entering rays of light parallel to one another before they reach a finely scored plate of glass known as a diffraction grating. A spectrograph splits light into its component wavelengths. Light entering a spectrograph can be split or dispersed into a spectrum by one of two means, using a prism or a diffraction grating.

School students often use perspex prisms from ray box kits to disperse or split white light from an incandescent bulb . An explanation of Spectrometers, Spectroscopes, and Spectrographs from Field Guide to Spectroscopy, SPIE Press. Please see our Spectrograph Guide for additional information. Sound spectrograph : A sound that changes in time, such as a spoken word or a bird call, can be more completely described by examining how the Fourier spectrum changes with time. Spectrograph definition, a spectroscope for photographing or producing a representation of a spectrum. Early on, such devices were mostly used for identifying absorption lines, in solar spectra and the spectra of burning gasses.

Recently the word has also been used to describe devices . SOPHIE is a cross-dispersed échelle spectrograph permanently located in a temperature-controlled chamber in the second floor of the 1. The spectrograph is fed . This provides a wavelength fingerprint of the object being observe which tells us about its temperature, . DOLORES (Device Optimized for the LOw RESolution), LRS in short, is a low resolution spectrograph and camara permanently installed at the Nasmyth B focus of the Telescopio Nazionale Galileo. Its design allows to perform imaging and low resolution spectoscopy observations.