Читать книгу Patty's Industrial Hygiene, Physical and Biological Agents - Группа авторов - Страница 80

Unfortunately, the term “mode” is confusing as it has many different meanings in optics and laser technology. It may refer to the time distribution or “temporal mode” of the output. That is, a pulsed or CW laser can be described as being a “pulsed mode” or “CW mode” laser. Similarly, a burst of laser pulses can be described as a “burst mode,” or “normal mode.” It may also refer to the spatial distribution of light within the laser beam. The term “mode‐locking” describes a method that results in a train (i.e. group) of evenly‐spaced pulses, where each individual pulse has an extremely short duration measured in picoseconds (ps); such pulses are sometimes referred to as “ultra‐short pulses.” Characteristically mode‐locking produces light pulses of higher power than does Q‐switching because the pulses are very much shorter.