Download Initial Confocal Displacement Sensor User`s Manual

Where D1 and D2 are the distances measured by the two sensors and the constant
K is determined using a standard with known thickness.
7.4.6 Teach functions for thickness measurement
130B
In the “Basic” page, set the measuring mode to Thickness. Set the “refractive
index” parameter value to the average refractive index of the sample in the visible
range. (If you do not know the precise value, leave it at its default value). In the
“Digital output” page, select Data n° 0 (Thickness). Set the other data to “Not
Transmitted”.
Place a thickness sample in the measurement range of the optical pen, such as a
glass slide, a piece of cellophane, a transparent plastic film or any other flat
transparent sample. If it is a sheet or a film, ensure it is pulled tight. Also check
that the axis of the optical pen is normal to the surface of the sample. The sample
thickness must be compatible with the thickness measuring range of the
optical pen.
In the “Measurement” page set the number of points to 3000, and click on “Start”.
Move the optical pen slowly backward and forward to bring the two faces of the
sample inside the measuring range. As soon as the sample is inside the measuring
range, non-zero thickness values appear in the Graphic window.
Note that of the “Measure” LED-indicator depends only on the presence and
position of the first peak, it does not tell if a second peak has been detected.
Note that the displayed thickness values are proportional to the refractive index
value.
Troubleshooting: If you succeed to obtain a measurement in “Distance” measuring
mode, but in “Thickness” measuring mode the measured thickness is zero, check the
following points:

The thickness of the sample must be compatible with the measurement range
limits

The sample must be sufficiently transparent.

The sample must be pulled tight.

The optical axis must be normal to the surface of the sample.

The sampling rate selected must be the lowest in the list

The two faces of the sample must be inside the measuring range
Acuity Intial Confocal Sensor
Rev 1.0
34