What distinguishes a laser from ordinary light sources?

What distinguishes a laser from ordinary light sources?

• A. A laser emits light through stimulated emission and is incoherent
• B. A laser produces monochromatic and coherent light
• C. A laser has a broader spectrum of colors
• D. A laser light is completely unpredictable

Answer: (B)

A laser is distinguished from ordinary light sources primarily by its ability to produce light that is both monochromatic and coherent. Monochromaticity means that the light emitted is of a single wavelength or color, which allows for very pure and well-defined colors. This is in contrast to ordinary light sources, such as incandescent bulbs, which emit a broad spectrum of colors. Coherence refers to the orderly phase relationship between the light waves emitted by the laser. In coherent light, all photons move in phase with one another, which means that the peaks and troughs of the light waves align. This coherence results in the ability for laser light to be focused into narrow beams over long distances and enables various applications like holography, laser cutting, and communication technologies. The combination of being both monochromatic and coherent is essential in defining the unique properties of laser light, making it useful in numerous applications that rely on precise control of light. These distinguishing features are what set lasers apart from other light sources, which tend to emit light that is a mixture of wavelengths and lacks the coherence needed for many high-precision applications.

A laser is distinguished from ordinary light sources primarily by its ability to produce light that is both monochromatic and coherent. Monochromaticity means that the light emitted is of a single wavelength or color, which allows for very pure and well-defined colors. This is in contrast to ordinary light sources, such as incandescent bulbs, which emit a broad spectrum of colors.

Coherence refers to the orderly phase relationship between the light waves emitted by the laser. In coherent light, all photons move in phase with one another, which means that the peaks and troughs of the light waves align. This coherence results in the ability for laser light to be focused into narrow beams over long distances and enables various applications like holography, laser cutting, and communication technologies.

The combination of being both monochromatic and coherent is essential in defining the unique properties of laser light, making it useful in numerous applications that rely on precise control of light. These distinguishing features are what set lasers apart from other light sources, which tend to emit light that is a mixture of wavelengths and lacks the coherence needed for many high-precision applications.