A polychromator's performance depends on essential features such as brightness, stability, spectral purity and resolution.
polychromator can be mounted with two gratings as shown below, with the
second grating taking its light from the zero order diffraction (direct
reflection) of the first grating. The photomultipliers can be mounted
in different veritical and horizontal positions using mirrors and
filters and other optical devices to optimise space. An example of the
inside of a polychromator with a 1 metre focal length for high
resolution is shown below:
the circular spectrometer, light enters from the top on the left hand
side, the grating is mounted inside the bottom left hand side, and the
photomultiplier tubes are mounted on the Rowland circle near the top
and right hand side.
First published on the web: 15 May 2000. Last modified:
20 November, 2007
Author: Richard Payling