Which of the following is NOT considered a laser parameter?

In the context of laser parameters, the focus is typically on characteristics that define the behavior and performance of laser systems. Wavelength, power output, and duration of exposure are all critical factors that describe how a laser will interact with materials and the effects it produces.

Wavelength is essential because it determines the laser's color and the type of materials that can be effectively illuminated or affected by the laser energy. Power output signifies the energy delivered by the laser over time and is a crucial factor in applications ranging from cutting to medical procedures. Duration of exposure is equally important as it influences the thermal effects and potential damage to tissues or materials being treated.

While fiber diameter is an important parameter related to the delivery of laser light through optical fibers, it does not directly define the laser itself or its fundamental operating characteristics. Instead, it pertains to the application side of laser technology and how the laser output is shaped or directed. Thus, it is commonly considered ancillary to the primary laser parameters.