What does nm mean for lasers?

Laser Wavelength: Nanometers (nm)

Nanometers (nm) is a unit of measurement that represents one billionth of a meter (1 nm = 10-9 meters). In the context of lasers, nm is used to specify the wavelength of the light that the laser emits. Wavelength is a fundamental descriptor of electromagnetic waves, including visible light, and it corresponds to the color of the laser light.

Significance of Wavelength in Lasers

Laser light is monochromatic, meaning it consists of one color or wavelength. The specific wavelength of a laser determines many of its characteristics, including its color in the visible spectrum and its applications.

Applications Based on Laser Wavelength

  • Visible Lasers: Lasers that emit in the visible range (approximately 400 nm to 700 nm) are used in applications such as pointers, laser shows, and holography.
  • Infrared Lasers: Lasers with wavelengths longer than visible light (above 700 nm) are used for applications like remote controls, fiber-optic communications, and medical procedures.
  • Ultraviolet Lasers: Lasers with wavelengths shorter than visible light (below 400 nm) are used for tasks that require precision such as semiconductor lithography, sterilization, and LASIK eye surgery.

Laser Safety and Wavelength

Laser safety guidelines are often wavelength-dependent because the human eye and skin respond differently to various wavelengths. For example, the eye is more sensitive to wavelengths in the visible spectrum, while UV and IR wavelengths can be harmful even at lower power levels. Proper laser safety equipment, such as goggles, must be selected based on the wavelength of the laser used.

Importance of Selecting Wavelength for Specific Applications

The wavelength of a laser affects its behavior in different media. For example, some wavelengths are better suited for atmospheric transmission, while others are absorbed or scattered less in water or biological tissue. This makes the choice of wavelength critical for the efficiency and safety of laser applications in diverse fields.

Back to blog