PerkinElmer Spotlight 400 Series, User Manual

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Preparing Samples . 55
Pressing with the heel of a probe
Press on small samples with the flat end of the probe handle. Even moderate pressure
usually produces considerable thinning.
Pressing with a needle
Pressing with the point of a needle or probe applies a high force per unit area, because the
area of contact is small.
Rolling a hard sample with the side of a sewing needle held in a pin vise presses it into a
flake.
Slicing Samples from Solids
Cutting a wedge of sample
Cutting a wedge-shaped piece from its edge enables you to produce a thin sample while
destroying very little of the original. This technique can be used with laminates, plastics,
films, paint chips and paper.
To cut a wedge-shaped piece from a relatively thick sample:

Hold the sample in tweezers as you slice a thin wedge from it with a razor blade. Taper
the wedge to as thin a slice as possible.
To cut a wedge-shaped piece from a relatively thin sample:
1. Place the sample between two offset glass slides. Allow a triangular portion of the
sample to protrude as shown on the left in Figure 17.
Figure 17 Cutting a wedge-shaped sample
2. Run a razor blade or the roller knife along the edge of the upper slide.
The triangular piece of the sample is sliced off, giving a wedge-shaped sample.
3. To mount the sample, rotate it so that it is positioned as shown on the right in
Figure 17.
4. Position it under the imager so that the infrared beam goes through the thin end of the
wedge.