3. Pulse generation

The pulsed mode of operation of lasers has long been of great interest to "laserists". The first laser source was a ruby that operated in pulses. Although there are a large number of lasers that operate both continuously and in pulses, some, such as excimer lasers, only deliver pulses. This depends essentially on the nature of the amplifying medium and the lifetime of the excited emitting level of the laser transition. Especially with pulse lasers, peak powers can be very high, making them particularly attractive for many applications. In recent years, progress in the generation of ultrashort pulses of light has been spectacular. Coupling with advances in diode-pumped solid-state lasers has even opened up new scientific and technological fields.