Newport ORIEL Instruments Cornerstone 260 - Diffraction Gratings

MCS260
CORNERSTONE 260 MONOCHROMATORS
21
6 DIFFRACTION GRATINGS
Diffraction gratings are used to disperse light, i.e. to spatially separate light of different wavelengths. They
have replaced prisms in most fields of spectral analysis. Two or three gratings are installed into the
Cornerstone 260 monochromator, depending upon the configuration selected. In general, the grating with
the highest efficiency is chosen at a particular wavelength. The optional Oriel TracQ™ Basic Data
Acquisition and Radiometery Software allows users to set up a specific grating switchover wavelength, so
the most appropriate grating will automatically be chosen while performing a scan over a range of
wavelengths.
The Cornerstone 260 monochromators feature diffraction gratings produced by Richardson Gratings.
Both Oriel Instruments and Richardson Gratings are part of the Newport family of brands, and have a
long history of working together to design monochromators that are appropriate for a wide variety of
applications.
A tutorial on grating physics may be found in the Appendix of this user’s manual.
The photo below illustrates diffraction gratings mounted into holders for installation into the Cornerstone
260 monochromator. The grating is precisely positioned on the mount using a fixture, and then the
grating angle is aligned by Oriel, with the screws locked into place using the red adhesive. An
unmounted grating cannot be installed by the user in the field; gratings must be installed onto the
appropriate mount for the Cornerstone 260 monochromator and aligned at the factory. The mount differs,
depending on whether it is a dual-grating or triple-grating instrument configuration.
Figure 15: Gratings Installed onto Mounts