Low Frequency Limit of Grating Message in OMNIC

Issue

OMNIC software is giving a message that say "Low frequency limit of grating (39.3) is outside the allowed range of 35 to 5 cm-1".

Environment

DXR3 SmartRaman

DXR3 Microscope

OMNIC for Dispersive Raman

Resolution

This message can be caused by the following:

• The most common cause is that the grating was recently installed and has not achieved thermal stabilization.  After installing a grating allow 15 to 20 minutes for warm up and stabilization.
• Another cause is if there is some debris or dirt on the magnets of the grating or in the spectrograph.  Ensure all magnets are clean and remove an debris that is found.
• The last possible cause could be if one of the locating rods on the grating or a ball bearing in the spectrograph is missing.  Check that these are in place.