Micrometre

A micrometre or micron (American spelling: micrometer; symbol µm) is one millionth of a metre, or equivalently one thousandth of a millimetre. It can be written in scientific notation as 1×10⁻⁶ m, meaning ¹⁄_1000000 m.

A strand of human hair is about 100 µm wide.^[1] Red blood cells are 7 µm in diameter.^[1]

The micrometre is a common unit of measurement for wavelengths of infrared radiation. The name micron and the solitary symbol µ (both of which were official between 1879 and 1967 ^[2]) are still used (especially in astronomy and the semiconductor industry) to denote a micrometre.

See also

• 1 micrometre (for a comparative description of the micrometre in the context of other orders of magnitude)
• SI
• SI prefix
• Metric system
• Orders of magnitude
• Micronization
• µ
• Nanometre

References