Although laser scanning is a relatively new technology, it has already found many applications in recording systems, OCR, film readers and data digitizers. A primary reason is that the monochromaticity and coherence of the laser beam makes it possible to focus the wavefront to a diffraction limited point image which then becomes the recording or analyzing spot.
M. J . Buzawa,
R. E. Hopkins,
"Optics For Laser Scanning", Proc. SPIE 0053, Laser Recording and Information Handling Technology I, (1 March 1974); doi: 10.1117/12.954193; https://doi.org/10.1117/12.954193