Calmar's femtosecond laser sources are passively mode-locked fiber lasers. Passive mode-locking makes these lasers easier to operate than actively mode-locked lasers, as no external RF clock signal is required, and little or no warm-up time is needed. Temperature control is also less of an issue with passive mode-locked lasers.
Calmar's passively-mode-locked lasers produce pulses as narrow as 80 fs wide. Repetition rates are fixed in the range 10 - 100 MHz. The peak output power of a femtosecond laser is, of course, high due to the short pulse durations, and peak powers up to 10 KW can be achieved using an integrated EDFA. Figure 1 shows a simplified schematic of a passively mode-locked fiber laser.