Laser optical quality

The output of a laser is nearly monochromatic and is extremely coherent. Narrow linewidth or long coherence length is the primary operational characteristic of a laser and it allows the laser output beam to be focused to a tiny spot. The optical quality of a laser is a measure of the laser’s focusability. This paper discusses various measurable parameters for quantifying the optical quality of lasers. Many industrial laser manufacturers provide some information on optical quality for their lasers. However, a full characterization is necessary after setting up a laser at the users’ facility. By defining a simplified set of optical quality parameters, the operational characteristics of all industrial lasers can be better understood.