6212A Manual Version 14.56.docx
Page 36 of 58
Alignment
Vertical
The specular laser beam must fall on one of detectors 3 to 9 n the 35-element photodiode array. If Lasercheck is
too close to the surface, the specular reflection falls on detector number 10 or greater. If Lasercheck is too far
from a surface, the specular laser beam falls on detector 2 or smaller, or misses the photodiode array entirely.
The image depicts the laser path and specular reflection from surfaces at three different distances from the
head. The bottom surface, the farthest from the head, shows the specular reflection about to strike detector 2.
This is misaligned – the head is too far from the surface. The top surface is also misaligned because the specular
beam is hitting higher than detector 9 on the detector array – the head is too close to the surface.
A good guideline is to try to maintain alignment so that specular falls on detector 6 with a tolerance of no more
than +/- 1 detector elements. As a reference, the head movement is approximately 0.010 inches for every shift
of the specular beam of one detector element.
Three Surface Locations – Too Close, Correct, Too Far