Technical Center: Laser Glossary of Terms

Nanometer (nm)

A unit of length in the International System of Units (SI) equal to one billionth of a meter. Abbreviated nm - a measure of length. One nm equals 10-9 meter, and is the usual measure of light wavelengths. Visible light ranges from about 400 nm in the purple to about 760 nm in the deep red.

Nanosecond

One billionth (10-9) of a second. Longer than a picosecond or femtosecond, but shorter than a microsecond. Associated with Q-switched lasers.

Nd:Glass Laser

A solid-state laser of neodymium: glass offering high power in short pulses. A Nd doped glass rod used as a laser medium to produce 1064 nm light.

Nd:YAG

Laser Neodymium:Yttrium Aluminum Garnet. A synthetic crystal used as a laser medium to produce 1064 nm light.

Near Field Imaging

A solid-state laser imaging technique offering control of spot size and hole geometry, adjustable working distance, uniform energy distribution, and a wide range of spot sizes.

NEMA

Abbreviation for National Electrical Manufacturers' Association, a group which defines and recommends safety standards for electrical equipment.

Neodymium (Nd)

The rare earth element that is the active element in Nd:YAG lasers and Nd:Glass lasers.

Noise

Unwanted minor currents or voltages in an electrical system.

Nominal Hazard Zone (NHZ)

The nominal hazard zone describes the space within which the level of the direct, reflected, or scattered radiation during normal operation exceeds the applicable MPE. Exposure levels beyond the boundary of the NHZ are below the appropriate MPE level.

Nominal Ocular Hazard Distance (NOHD)

The axial beam distance from the laser where the exposure or irradiance falls below the applicable exposure limit.