What is a characteristic of light in a laser beam?

A laser beam is characterized by its coherent nature, which means that it consists of a limited range of wavelengths that are all in phase with one another. This coherence results in the laser light having a very specific color or wavelength, depending on the type of laser being used. The waves being in phase means that their peaks and troughs align with each other, which contributes to the beam's focused and directional properties.

This coherence is what makes laser light fundamentally different from ordinary light sources like incandescent bulbs or fluorescent lights, which emit a wide range of wavelengths and have light waves that are not in phase. Because of its in-phase characteristic, a laser beam can be focused into a tight spot, which is useful for applications ranging from cutting and welding to optical communication.

The notion of low intensity does not apply to laser light; in fact, lasers can produce very high-intensity beams. Additionally, the wide range of wavelengths is not a characteristic of laser light, as lasers are designed to emit light at specific wavelengths. Thus, the coherence and limited range of wavelengths all in phase are what define the unique properties of laser beams.