Photonics Dictionary: P

A phase screen, in the context of optics and wave optics, refers to a surface or medium that introduces a phase delay to an incident wavefront passing through it. This concept is often used in the...

A lens system that is capable of producing a 360° image, or one that is very close to that. In recording, the image may be formed on a curved strip of film surrounding the lens, resulting in a...

One eyepiece of a set having equal distances from their mounting interface to their image plane, permitting freedom to interchange eyepieces without the need to refocus.

A pentamirror is an optical component found in SLR cameras, composed of multiple flat mirrors arranged in a pentagonal configuration. Its primary function is to redirect light from the camera lens to...

A pentaprism is a five-sided glass prism used in optical devices, particularly in SLR cameras, to deviate the path of light by 90 degrees and ensure that the image seen through the viewfinder is...

Typically represented by the Greek letter μ, magnetic permeability is the measure of a material's ability to generate and sustain a magnetic field within itself when an external magnetic field is...

In optics and photonics, "phase" refers to a property of electromagnetic waves, such as light, that describes the position of a wave at a given point in time within its oscillation cycle. More...

The use of a reflective device, which can be fashioned from a variety of materials including gases, solids, dyes, aerosols, semiconductor crystals and plasmas, to replicate a laser beam by reversing...

In optics and photolithography, a phase mask refers to a device that modifies the phase of light waves passing through it. The phase mask is used to control the spatial distribution of the light's...

Very small phosphor particles present on the screen of a picture tube.

The conductivity increase exhibited by some nonmetallic materials, resulting from the free carriers generated when photon energy is absorbed in electronic transitions. The rate at which free carriers...

A system having a photoelectric detector for the measurement of three quantities related by linear combination to tristimulus values of a sample.

The measurement and analysis of color using a photoelectric instrument having three filters with broad spectrum bands.

Photogrammetry is a technique used to obtain accurate three-dimensional measurements of objects and environments through the analysis of photographs or imagery. It involves extracting information...

A photomask, also known simply as a mask or reticle, is a key component in the photolithography process used in semiconductor manufacturing and other areas of microfabrication. It is a high-precision...

Photocells of various kinds used to measure photometric quantities; i.e., intensity, luminance and illuminance. Meter readings are used to express illuminance and, by calibration, to measure...

Photonic crystals are artificial structures or materials designed to manipulate and control the flow of light in a manner analogous to how semiconductors control the flow of electrons. Photonic...

A phototransistor is a type of semiconductor device that converts light energy into electrical signals. Similar to a regular transistor, it consists of a semiconductor material (such as silicon) with...

Photovoltaic (PV) refers to a technology that converts sunlight directly into electricity using semiconductors. The term "photovoltaic" is derived from the words "photo," meaning light, and...

Piezoelectricity is a property exhibited by certain materials in which they generate an electric charge in response to mechanical stress or deformation, and conversely, undergo mechanical deformation...

A PIN photodiode is a type of photodetector or semiconductor device used to convert light signals into electrical signals. The name "PIN" is derived from the arrangement of the three semiconductor...

A lensless photographic camera that uses a small sharp-edged hole as its aperture. The light passed by this aperture onto the camera's film plane produces a soft-edged image that has a wide field of...

A vacuum gauge designed to measure very high degrees of vacuum by thermal conduction.

Pixel pitch refers to the distance between the centers of two adjacent pixels on a display screen or imaging sensor. It is typically measured in millimeters and is a crucial specification in...

A pixel, short for "picture element," is the smallest controllable element of a digital image or display. It is a fundamental unit that represents a single point in a raster image, which is a grid of...

An instrument designed to give precise and rapid detection of changes in tumor growth as well as the location of small tumors by providing a three-dimensional picture of the tissue.

Operates with light collectively emitted by the recombination of free electrons and ions in the plasma state.

Plasmon ion-assisted deposition (PIAD) is a technique used in thin-film deposition processes, particularly in the production of optical coatings. This method combines two key processes: plasmon...

Plasmonics is a field of science and technology that focuses on the interaction between electromagnetic radiation and free electrons in a metal or semiconductor at the nanoscale. Specifically,...

The property exhibited by certain birefringent crystals in which the degree with which they transmit polarized light is different, depending on whether the ray is ordinary or extraordinary. An...

A point cloud is a set of data points in a three-dimensional coordinate system, where each point represents a specific location in space. These points are typically obtained through various sensing...

A polariton is a quasiparticle resulting from the strong coupling between photons (light particles) and certain types of excitations in a material, such as electronic excitations (electrons and...

A tough, durable, heat- and cold-resistant optical quality plastic used in injection-molded items such as streetlight lenses, automotive taillights and audio compact discs.

A polygonal mirror, also known as a multifaceted mirror or facet mirror, is a type of optical component used in various laser systems, optical scanners, and imaging devices. It consists of a flat or...

The polymerase chain reaction (PCR) is a widely used molecular biology technique used to amplify a specific segment of DNA (deoxyribonucleic acid) through a series of temperature-controlled cycles....

A thermoplastic, self-extinguishing polymer with excellent high-temperature, low-creep and arc resistance properties.

Optical fiber channel characterization scheme based on three assumptions; the discrete mode spectrum can be replaced by a continuum; the loss due to coupling between guided and radiation modes...

A set of three colored lights which, when mixed, give the sensation of white light. The set used in color television, for example, is red, green, blue (RGB).

A photographic enlarger with a fixed negative plane and a fixed paper plane, often using a roll of paper that is advanced automatically between exposures. The lens is interchangeable to suit a range...

Acronym for profile resolution obtained by excitation. In its simplest form, probe involves the overlap of two counter-propagating laser pulses of appropriate wavelength, such that one pulse...

A lens that is symmetrical and designed to work between 1:1 and about 4:1. It covers a field of about ±20° at f/8 or f/10, and may have a focal length up to about 30 in., although the usual...

A device that couples a light source to an optical fiber by projecting an image of the source and the fiber core onto a screen where they can be superimposed by micropositioners.

A device used to project a small area of light on a screen for indication.

The measurement of surface temperature by a thermograph that forms a pattern of the heat radiated by the surface on a luminescent screen.

Protein crystallography is a scientific technique used to determine the three-dimensional structure of proteins at atomic resolution. It involves growing crystals of a protein of interest and then...

A planar photocathode and a planar phosphor screen mounted in a close-spaced parallel configuration in an evacuated enclosure so that the ensemble of photoelectrons emitted from each photocathode...