how auto-collimator work?

Answer 1

An auto-collimator is an optical instrument for non-contact measurement of angles. They are typically used to align components and measure deflections in optical or mechanical systems. An auto-collimator works by projecting an image onto a target mirror, and measuring the deflection of the returned image against a scale, either visually or by means of an electronic detector. A visual auto-collimator can measure angles as small as 0.5 arcseconds, while an electronic auto-collimater can be up 100 times more accurate.