Thermo Scientific Nicolet Continuum, User Manual

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Thermo Scientific 168
Testing
microscope
performance
To confirm that the microscope is performing well, you should
periodically measure its performance. Typically the signal-to-noise
ratio (SNR) from 2600 to 2500 wavenumbers is used for this
purpose. (The following procedures give the desired noise level
limits.)
Follow the instructions in the next sections to check the microscope
performance using a noise test. You should run the test at least once
a week in both transmission mode and reflection mode. (If you will
be performing only reflection experiments, you do not need to run
the test in transmission mode.)
Before you begin…
Make sure the single-element detector is cooled and selected, the
objective is focused. If you plan to run the test in transmission mode,
be sure the condenser is focused and centered.
See “Cooling the detector” in the “Preparing the Microscope”
chapter and “Selecting a detector” in the “More about hardware”
chapter if you are not familiar with the procedures for cooling and
selecting the single-element detector.
See “Preparing the optical components” in the “Preparing the
Microscope” chapter if you are unfamiliar with the procedures for
focusing the objective, focusing the condenser, and centering the
condenser.
In reflection mode
Follow these steps to run the noise test in reflection mode:
1. Open the Atlµs window and initialize the Reflex aperture.
This gives an aperture size of 100 by 100 µm if you are using the
15X objective, or a size of 46.875 by 46.875 µm if you are using
the 32X objective.