Diagram of a multichannel spectrometer based on a grating
spectrograph with an array detector. Radiation from the tungsten or deuterium
source is made parallel and reduced in size by the lens and diaphragm. Radiation
transmitted by the sample enters the spectrograph through slit S. Collimating
mirror M1 makes the beam parallel before it strikes the grating G. The grating
disperses the radiation into its component wavelengths, which are then focused
by focusing mirror M2 onto the photodiode or CCD array A. The output from the
array detector is then processed by the computer data system.