In this section, we will explain some important parameters of lasers.

The power of a laser is the output optical power of the laser, we need to know the normal working power and its maximum allowable power. Lasers operate in either continuous wave state or pulsed state. Both operation states have lots of applications. For pulsed laser, an important parameter is the peak power. In general, CO₂ lasers have relatively high continuous wave power, while Nd:YAG lasers can provide relatively high peak power for pulsed operation. Output power is closely related with processing time and operation expense. If the selected laser power is lower, the processing time will be increased, if the selected laser has too high power than necessary, the operation expense will be higher than necessary. So the proper choosing of laser power is very important.

Absolute Energy is the total energy in a laser pulse or system, unit is Joule (J), a typical value for a single laser pulse is 100 mJ.

Wavelength (l ):

The Wavelength (l ) of a laser is decided by the related stimulated energy transition. Laser light is very pure, this means their wavelength vary in very small ranges when compared with normal light. Different wavelengths may have different effects when interacting with matters. The shorter the wavelength, the higher the energy of the photon. Laser can also be divided into infrared, visible, ultraviolet lasers according to their output light wavelength. Wavelength also affects the maximum resolution and focalization, the shorter the wavelength, the higher the resolution, the better the focal property.