PerkinElmer Spotlight 400 Series, User Manual

Page: 85 / 120

Techniques for Collecting IR Images and Spectra . 85
Removing the ATR Crystal Holder from the
Imager
To use the imager for conventional microspectroscopy or imaging, you need only retract the
ATR crystal from its working position. If, however you need a very large working distance,
for example if the sample is recessed, the ATR crystal holder can be removed.
1. Switch off the imager at the electricity supply.
2. Stop any laser radiation from entering the imager by switching the internal beam of the
spectrometer to the internal sample compartment.
See the Spectrum on-screen Help for further information.
3. Make sure that the ATR crystal is in the raised position.
4. Screw the plastic protective cover in place, over the crystal.
5. While holding the crystal assembly, unscrew the two adjustment thumbnuts completely.
Allow the assembly to drop vertically from the cassegrain. Be careful not to disturb the
two adjusting levers. Any movement of the adjusting levers will change the alignment of
the assembly when it is refitted.
6. Store the assembly carefully for future use.
When refitted, the assembly will still be aligned if the adjusting levers have not been
moved.
7. Direct the infrared beam back to the imager.