THORLABS GAN1x1 Series, Руководство пользователя

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SD-OCT Base Unit Chapter 4: System Operation
Page 32 MTN020880-D02
Figure 34 B-Scan of an IR Viewing Card
After basic alignment, you need to adjust the focus position inside your sample by use of the fine focus adjuster
(see Figure 28) of the OCT-STAND. Then, the final position of the OCT image in the B-scan or volume can be
set using the reference length adjustment knob, which will move the image up and down until you achieve the
desired location.
Figure 35 B-Scan of a Fingertip Out of Focus and In Focus
In Figure 35, two images of a fingertip are shown: the left is out of focus and the right is in focus.
One or more of the following features are characteristic for the sample being in focus:

Sharp (thin) features in lateral direction

Autocorrelation terms (see chapter 5.3)

Higher contrast (i.e. a strong signal). Note that the focus does not always have to be on the top surface
of your sample, but it needs to be adjusted to the layer of interest in your sample.