micrometer

A micrometer (sometimes expressed using the obsolete term, micron ), is one-millionth of a meter and can also be expressed as:

• 10 ^-6 meter
• One thousandth of a millimeter
• One 25-thousandth of an inch

The micrometer is a unit of measure for the core in optical fiber , for which the most common diameter is 62.5 micrometers. It is also used to measure the line width on a microchip . Intel's Pentium 4 microprocessors are built using 0.18 or 0.13 micrometer line widths. AMD's Athlon uses a 0.18 line width.

A human hair is said to be about 50 micrometers wide.