Laserimpulses

Laserimpulses, commonly called laser pulses, are brief bursts of coherent electromagnetic radiation emitted by a laser. They are characterized by their duration (from femtoseconds to milliseconds), energy per pulse, peak power, repetition rate, spectral bandwidth and temporal shape. Shorter pulses typically have broader spectral bandwidths because of the time–bandwidth relationship.

Production of laserimpulses uses techniques that force a laser to emit in bursts rather than continuously. Common methods include Q-switching for high-energy nanosecond pulses, mode-locking for ultrashort (picosecond to femtosecond) pulses, and chirped pulse amplification for boosting peak power while avoiding damage to gain media. Pulse shaping and compression techniques control temporal and spectral profiles for particular applications.

Applications span science, medicine and industry. Ultrafast pulses enable time-resolved spectroscopy and the study of chemical and biological dynamics. High-energy pulses are used for material processing, micromachining and laser cutting. In medicine, short laser pulses facilitate precise tissue ablation and ophthalmic procedures. Pulsed lasers are also integral to lidar, rangefinding and certain telecommunications systems.

Measurement and characterization employ instruments and methods such as photodiodes for temporal envelopes, autocorrelation, frequency-resolved optical gating (FROG) and spectral phase interferometry for direct electric-field reconstruction (SPIDER) to resolve pulse duration and phase. Safety considerations include the risk of eye and skin injury, stray reflections and fire hazards; appropriate eyewear, enclosures and interlocks are standard controls.