Lasers: Understanding the Basics | lasers | Photonics Handbo ..
Ultrafast lasers.. Ultrafast lasers are generally defined as lasers that produce pulses in the range of 5 fs to 100 ps (1 femtosecond = 10 −15 seconds).. If a laser is able to oscillate in many longitudinal modes, such short pulses can be produced with the so-called mode-locking technique..