Repeatability
The three-sigma variation of multiple readings on the same object that is
positioned at multiple locations across the field of view.
Resolution
The least significant digit to which a physical quantity can be read. High
resolution does not imply high accuracy.
Squareness
The alignment of the camera relative to the motion of the metrology stage.
If the camera is misaligned (out of square), the image will drift diagonally as
the stage position is moved along one axis.
Telecentric
A lens property where the light from the object stays parallel to the optical
axis across the entire field of view, thereby eliminating optical distortion.
This can only happen if the entrance aperture of the lens is larger than the
field of view, requiring a large and expensive lens.
Object Telecentric lens CCD detector
Zoom Optics
Optics which can change magnification based on a user selection. Zoom
control can be manual or motorized, depending on the metrology system.
Rev. C. July 5, 2018
P/N 5930
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