A range of lenses are available but typically 10X or 20X are used to magnify a shadow of a workpiece that is projected on the screen. The precision workstage is adjusted to bring the feature into alignment with the crosshairs, for point to point measuring or angle via the screen protractor. Overlays can been placed on screen with thread profiles, radii, angles, or special printed outlines of the workpiece for direct comparison.
The option of auto edge detection will further enhance functionality and maximise repeatability between operators. This can easily be retrofitted to most projectors by the installation of a screen mounted edge sensor, processor unit and software; providing 2D measuring functions, graphical reporting, SPC capability and charting.