Photonics Dictionary: M

Minimum object distance, often abbreviated as MOD, refers to the closest distance at which a camera lens or optical system is capable of producing a sharp and focused image. In photography, this term...

The smallest object that may be seen, measured in terms of the angle subtended by the object measured at the eye. Also referred to as minimum perceptible color difference (MPCD) which is a unit of...

In a thermal imaging system, the smallest change in blackbody equivalent temperature that can be detected clearly by the system as a function of target frequency.

The least space between two parallel lines that can be discriminated as a gap to the human eye. It is measured in terms of the angle subtended by the gap measured at the eye.

The smallest linear diameter to which a laser or other beam of radiant energy is capable of being focused, depending on the quality of the focusing optics, aperture and focal length, beam irradiance...

The smallest area of uniform brightness that can be seen by the eye. It is measured in terms of the solid angle subtended by that area from the eye.

The distortion of an object's true image as the result of abnormal atmospheric disturbances along the path traveled by the light. The atmospheric disturbances common with mirages are a result of a...

A smooth, highly polished surface, for reflecting light, that may be plane or curved if wanting to focus and or magnify the image formed by the mirror. The actual reflecting surface is usually a thin...

A mirror blank refers to the initial piece of material from which a mirror is made. It is typically a flat or slightly curved piece of glass or other substrate that serves as the starting point for...

One or more thin-film layers of optical material deposited on a mirror blank/substrate in order to enhance the way that substrate reflects light. For example of optical materials/optical coatings...

An image-forming system having curved mirrors in place of transparent glass components. Mirror lenses are commonly used for astronomical purposes as well as cheap solutions for very long focal length...

A mirror mount is a mechanical device used to secure and precisely position mirrors in optical systems. Mirrors are essential components in optical setups for reflecting light or redirecting laser...

The observation and measurement of the flatness of a mirror surface by contacting an optical flat with the mirror. The process generally is done before coating so as not to damage the delicate coated...

A homogeneous solid solution with crystal lattice sites occupied, at random, by the molecules or ions of two or more separate compounds

The simultaneous occurrence of specular and diffuse reflection.

The simultaneous occurrence of direct and diffuse transmission.

A mixed-signal oscilloscope (MSO) is a type of electronic test instrument that combines the capabilities of both a traditional oscilloscope and a logic analyzer. It is designed to capture and display...

Combining light beams, usually of unlike frequencies, to form a single beam with a frequency that is equal to the frequency sum or difference of the original beams. The resultant 'beat' frequency is...