Operating Principle; How To Measure - DeFelsko PosiTector RTR 3D Mode D'emploi

The PosiTector RTR-3D uses two measurement principles: a digital
micrometer to measure the overall height of the burnished replica
tape, and an optical system that projects light through the replica tape
and captures a two-dimensional black and white image.
The digital micrometer is used to measure the overall thickness of the
burnished replica tape. After subtracting the thickness of the
incompressible polyester film and linearizing the result (pg.12), this
thickness corresponds to the average maximum peak-to-valley height
(H).
It is known that replica tape transmits light proportionally to the degree
to which it is compressed. Peaks in the surface profile compress the
replica tape and result in bright spots, while valleys compress the
replica tape less, and result in dark spots. By recording the amount
of light transmission at each point on the burnished replica tape, a
precise 3D map of the surface can be generated. 2D and 3D surface
profile parameters can be measured.
The PosiTector RTR-3D uses a light intensity versus thickness
algorithm to produce three dimensional (3D) images of the replicated
surface burnished using Replica Tape. The image sensor produces a
1024x1024 pixel image that represents an approximate 3.8 mm x 3.8
mm image area. Images generated within the gage are analyzed to
produce 2D and 3D parameters that represent specific characteristics
of a surface.
1. Prepare the test surface
2. Burnish the replica tape
3. Prepare the Gage
4. Measure
1. Prepare the Test Surface
Locate a representative site for measurement. Clean the surface to
be tested. DeFelsko recommends the use of the included putty to
remove dust, debris, or residual blast media from the surface. Firmly
press the putty onto the surface using your fingers, and remove.
NOTE:
Ensuring a clean surface is especially important when using
the PosiTector RTR-3D to measure 2D and 3D parameters or
generating SDF files for post processing.

Operating Principle

How to Measure

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