Photonics Dictionary: M

meter;mass;milli- m is the standard unit symbol for length in the International System of Units (SI). 1 meter is equivalent to 3.28 feet. m is also the standard symbol for mass; m is also the standard SI metric unit prefix milli- which represents one thousandth i.e. 10-3, of a given unit.

mega;magnification -SI metric unit prefix which represents one million, 106, also the standard symbol for the magnification of a given optical system.

milliamperes-second - unit measure of electric charge acquired when multiplying the electric current in milliamperes (one thousandth or 10-3 of the standard unit for electric current the ampere) by the time in seconds. It is commonly used to describe the length of time that electrons are produced or passed through a given circuitry.

megabit — The megabit (also expressed as Mbit) is equivalent to one million (or 106) of the standard unit for digital information storage in telecommunications which is the bit.

megabyte — The megabyte (also expressed as Mbyte) is equivalent to one million (106) of the standard unit for digital information storage in computing which is the byte.

megabytes per second — The megabyte per second (not to be mixed up with the Mb/s -- megabits per second) is a unit of data transfer rate equivalent to one million (106) bytes per second over a given information network.

megabits per second — The megabit per second (not to be mixed up with the mbit/s – millibit per second, or Mbitps- megabit picosecond) is a unit of data transfer rate equivalent to one million (or 106) bits per second over a given information network.

millicandela — The millicandela is equivalent to one thousandth (or 10-3) of the standard unit of luminous intensity that is the candela, which is the power emitted by a given light source in a particular direction.

modulation contrast microscopy; multichip module — modulation contrast microscopy is a unique illumination technique that enhances contrast in an imaging microscope by converting optical gradients into variations in light intensity. Modulation contrast microscopy is found most commonly in live cell imaging, polarization microscopy, phase contrast, and oblique illumination of stained, unstained and birefringent specimens. A multichip module is an electronic packaging system where multiple discrete electronic components (integrated circuits, semiconductor diodes, etc.) are packaged in various ways onto a single substrate.

mercury cadmium telluride — Mercury cadmium teluride (HgCdTe) is a specific alloy combination that allows one to obtain any optical absorption bandgap of the material between 0 and 1.5 electron volts (eV) making it completely transparent at photon energies and wavelengths below the energy gap in the infrared.

many-element laser; maximum excess loss (MEL) — the many element laser is a laser unit that consists of N like elements of active materials for support with the mode selection of the laser output. The mode selection properties of a many element laser have been experimentally exploited with as many as 10 like elements. Maximum excess loss is the maximum power lost within a give system (typically a fiber optic communication system) including scattering, dispersion, absorption and coupling loss.