What is a CW Laser?

A CW or continuous-wave laser is any laser with a continuous flow of pump energy. It emits a constant stream of radiation, as opposed to a q-switched or mode-locked pulsed laser with a pulsed output beam. A laser is typically defined as having a pulse width greater than 250 ms. The first CW laser was a helium-neon (HeNe) gas laser, developed in 1960, which you can read more about in this blog “HeNe Lasers: Bright Past, Brighter Future.” If you want to read more about the types of CW Lasers we offer, check out the Overview of CW Lasers section on our Lasers 101 Page!