Photomultiplier Module - NT-MDT NTEGRA Spectra Instruction Manual

NTEGRA Spectra Probe NanoLaboratory. SNOM Measuring Head. Instruction Manual

1.3.4. Photomultiplier Module

Photomultiplier module (PMT module) (Fig. 1-16) serves for converting optical radiation
acquired from the sample into electrical signals.
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ATTENTION! The photomultiplier is highly sensitive to light. Never
illuminate the PMT (even when it is off) with high intensity to prevent its
damage or degradation. Avoid overloading the PMT.
The detected radiation comes to the PMT module through the laser beam delivery system
that connects with the slip bushing 1 (Fig. 1-17). The module is equipped with an
adapting bushing that corresponds to design of the laser beam delivery system in use.
Spectrum of the radiation acquired by the PMT can be transformed (by suppression,
extraction, or shifting of the desired band) with filters. For example, the fluorescent
component of the scattered radiation can be detected if the primary wavelength is
suppressed. The desired filter (diameter 25.4 or 25.0 mm) is placed in the cartridge 2 and
secured with the fixing nut 3.
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Fig. 1-16. PMT module
Fig. 1-17. PMT module
1 – slip bushing; 2 – cartridge; 3 – fixing nut