Photonics Dictionary

A specific method for measuring the diameter of irregular shaped particles, Martin's diameter is the measured distance between opposite sides of a particle, and is measured transverse to the particle...

In the context of thin film deposition processes such as evaporation or sputtering, masks are used to selectively deposit material onto substrates, creating patterns or structures with precise...

A term used to describe a nondirectionally diffusing surface that, when illuminated, appears equally bright from all angles. An example of this kind of surface is the screen used for the forward...

A thin layer of metal deposited on the surface of a substrate. The film may serve as a reflector, beamsplitter, neutral density filter or electromagnetic interference filter.

A specially designed microscope for observing the etched surface of a polished metal specimen. The specimen is often laid face down on a horizontal stage and observed from beneath, the illumination...

A small optical polishing machine intended for polishing the surface of a metal specimen before etching for examination under a microscope. Although shaping and polishing machines for this purpose...

A microbubble resonator is a device used in photonics and optical physics for the precise manipulation of light waves. It consists of a micro-sized, gas-filled spherical cavity (the "microbubble")...

A microchannel plate (MCP) is a specialized electron multiplier device used in various applications such as particle detection, imaging, spectroscopy, and night vision technology. It consists of a...

The formation of transistors, diodes, capacitors, resistors and other electronic elements directly on a flake of silicon by etching and selective absorption of doping elements. A circuit diagram...

The fundamental tool of microdensitometry, the microdensitometer is an instrument used for the precise measurement of microscopic optical densities (i.e. optical absorption) by detection of faint...

A technique for producing micron-size structures on surfaces by using short-wavelength light or electron beams.

A device that provides means for accurately moving minuscule tools over the surface of a microscopic object. The motion precision of a micromanipulator exceeds that of the unaided human hand....

An instrument capable of measuring the transmitted or reflected luminance from a very small area seen under a microscope. Microphotometers are the fundamental tools of microphotometry and are also...

A laser-induced scar on experimental bare glass surfaces usually attributable to threshold damage and indicative of isolated damage-susceptible areas in the glass.

A miniature projecting device designed to enhance and reproduce the image generated by a smaller image-forming instrument. Microprojectors can be used to determine the image-forming qualities of...

The pattern of microwave field intensity that can be obtained by detecting the minute expansion of a microwave absorber slab when heated by the microwave field, accompanied by moiré interference of a...

An automatic surface-generating process involving the removal of a material from a given surface. Optical milling typically involves the abrasion of glass by a diamond-charged wheel.

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...

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...

Mode hopping in the context of lasers refers to a phenomenon where a laser system abruptly switches from one longitudinal mode to another. In a laser, different longitudinal modes represent distinct...

Modified chemical vapor deposition (MCVD) is a technique used in the fabrication of optical fibers. It is a specialized form of chemical vapor deposition (CVD) that is employed to produce...

Material hardness scale that is used to characterize the scratch resistance of various materials. This surface hardness evaluation is determined by scratching the surface to be tested with 10...

A blank whose basic surface curves are attained by heating and forming a given weight of raw glass; a rough glass blank resembling the finished lens in size and shape. After molding, a precision lens...

A molded lens is an optical lens manufactured using a molding process, typically involving the shaping of a material, such as glass or plastic, into the desired lens shape. This process involves...

In physics, momentum transfer is the amount of momentum transferred from one particle to another during particle collision or interaction. This phenomenon can be utilized in various areas of physics...

A matrix-controlled display that has no information storage at the display surface.

One surface of a nonconducting plate that is coated with many minute particles of photoemissive material that are insulated from one another.

A metal-semiconductor-metal (MSM) photodiode is a type of photodetector that consists of metal electrodes on a semiconductor material. Unlike the more common PIN photodiodes, which have a P-type and...

The use of narrow bandpass filters and special photographic emulsions to discern features of a surface that would not be easily recognizable with regular black-and-white or color photographic methods.

Nanoplasmonics is a branch of nanophotonics that focuses on the study and manipulation of optical phenomena at the nanoscale using plasmonic materials and structures. Plasmonics deals with the...

A defect in infrared systems that appears as a dark circular area on a displayed image, caused by radiation reflecting into a detector. It can be reduced by low-reflective coatings or by altering the...

An imaging system designed to highlight small deviations in a planar reflective object such as a mirror. The system can be used to detect minute flaws or to image faint marks that are made in the...

A scanning probe microscope that analyzes the surface of a specimen by recording the intensity of light as it is focused through a pipette and raster scanned across the specimen at a distance less...

The series of rings or bands formed when light beams reflected from two polished, adjacent surfaces, placed together with a thin film of air between them, interfere. By counting these bands from the...

A prism invented by William Nicol in 1828 that is made of calcite, the end faces of which are ground to an angle of 68° between one vertical side and the end surface. The prism is cut diagonally...

Also referred to as differential interference contrast (DIC) microscopy; Nomarski microscopy is a unique form of microscopy especially suited for the evaluation of surface quality and defects as well...

Sometimes referred to as the surface normal or 'surface norm'; the normal is an axis that forms right angles with a surface that light is incident upon or with other lines. The normal is used to...

Condition in which a perpendicular surface can be discovered for every ray in a group. This condition is commonly observed when rays emerge from a point source or object that is placed at the center...

The emergence of a ray along the normal to the emergent surface of a medium.

Light striking a surface at an angle perpendicular to the surface.

A lens used in the optical testing of an aspheric surface. It converts a spherical wavefront into one that precisely matches the surface under test. When the wavefront is reflected from that surface,...