Adjusting The Delivery Channel - NT-MDT NTEGRA Spectra Instruction Manual

NTEGRA Spectra Probe NanoLaboratory. SNOM Measuring Head. Instruction Manual
3. Focus the objective on the sample surface by rotating the screw 3 (Fig. 4-1). Watch
the surface image on the monitor of the optical viewing system.
4. Open the laser exit shutter. The laser beam will go through the LBDS and the optical
tube and come to the sample.
5. Focus the lens of the optical tube on the sample surface by moving the optical tube
along Z direction with the screw 6 (Fig. 4-1) of the positioning device. With proper
focusing, the laser spot will be of the least diameter (Fig. 4-2).
6. Mark the centre of the focused laser beam on the monitor of the optical viewing
system using a mark pen.
7. Close the laser exit shutter.
This completes fine adjusting the detection channel.

4.2. Adjusting the Delivery Channel

Adjusting the laser beam delivery channel should provide proper positions of the laser
beam and of the probe for the sample surface to be irradiated at that point where the
transmitted radiation is collected by the optical detection system. For adjusting, the laser
beam is directed to the focus of the detection system and then the center of the probe
aperture is moved to the focus of the laser beam.
For adjusting the delivery channel, the optical scheme of the Transmission Collection
Mode, that is, the optical tube is connected to the PMT module through the LBDS while
radiation from the laser source is directed to the spectral unit.
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Fig. 4-2. Image of the focused laser spot