How do laser scan micrometers work? The technology behind the laser scan micrometer involves elements of simple optics. An object or part of interest is placed between the source of the laser beam and the receiving end on the micrometer. Then, a rotating optical element reflects or refracts the laser beam across the middle measurement area where the object or part is located. As the laser travels across this path, it is obstructed by the object or part, thus resulting in a shadow on the receiving end which is proportional in size and timing to the object or part being measured. The amount of the laser beam that successfully travels to the receiving end is collected and focused onto a photocell, where it is analyzed to detect the precise size and timing, which can then be converted into the final measurement.