Cypher SPM
User Guide
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(left) The blue arrows on the top/right of the View Window can be used to move the blue spot
position in all directions. If enabled, the blue box follows the location of the moving blue spot.
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(right) Clicking on the center circle in between all four arrows commands the blue light to move
on top of the infrared detection light spot.
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16.7.3 39.5.4 Acquiring a cantilever tune
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The optimal location for the blue spot for best photothermal performance is the base of the can-
tilever, along the axis of the cantilever. An example of the optimal location for several levers is
shown on the right.
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For hollow triangular cantilevers, the blue spot should be placed at the base of either of the can-
tilever legs.
Although it is not necessary to fine-tune the blue spot location, it may be beneficial in certain cases
to move the blue spot with the arrows near the cantilever base in order to find the position with
the maximum amplitude.
16.7.4 Operating on the thermal resonance
The true resonance of the cantilever is best determined from a fit to the thermal spectrum of the
cantilever. This ensures that the cantilever is being driven at its true resonance, where the phase
response is 90 degrees. For ultimate accuracy, the thermal should be acquired with the blue light
positioned where it will reside during imaging.
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16 blueDrive photothermal excitation
