Photonics Dictionary: P

Noise created by patterns imaged on a CCD surface. Pixel sensitivity is altered by responsivity during illumination.

A manufacturing process used to construct substrates for large optical components. Used with IR materials, planform bonding permits the joining of several smaller pieces to be used in place of a...

A glass structure from which an optical fiber waveguide may be drawn.

A series of capacitors and inductors connected to the flashlamp in a pumped Nd:YAG laser system in order to regulate the pulse shape of the current delivered to the lamp at a given operating voltage.

A semiconductor material in which the dopants create holes as the majority charge carrier. It is formed by doping with acceptor atoms.

The transmission of data in groups (packets) of information~comma~ each handled as an aggregate.

A camera designed to form a continuous record of an expansive section of the horizon. The typical panoramic camera is mounted to rotate about a vertical axis. A slit opening in the film plane and 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...

A concave mirror that has the form of a paraboloid of revolution. The paraboloidal mirror may have only a portion of a paraboloidal surface through which the axis does not pass, and is known as an...

The optical phenomenon that causes relative motion between two objects when the eyepoint is moved laterally. When parallax appears in a telescope between the image and reticle, this indicates the...

A mode of data transmission whereby bits of information are carried simultaneously at different frequencies over a single channel.

A pair of waveguides with axes normal to the plane and that guide uniform cylindrical waves.

An OLED display formed by creating an array of OLED pixels connected by intersecting anode and cathode conductors arranged in rows and columns. Electrical power is passed through selected pixels by...

A thin film or coating that forms on various finished surfaces. On optical surfaces it usually denotes aging.

A form of dispersing prism, often used in monochromators, that consists of a common right-angle prism with a 30° dispersing prism attached to each of its square faces. The spectrum formed by the...

A Peltier cooler, also known as a thermoelectric cooler (TEC) or thermoelectric module, is a solid-state device that uses the Peltier effect to transfer heat between two electrical junctions. It can...

The term perovskite refers to a specific crystal structure commonly found in various materials. Perovskite structures have a cubic arrangement of oxygen ions, forming a framework within which other...

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...

Phase distortion refers to a change in the phase relationships between different frequency components of a signal. In the context of signal processing, it occurs when the phase response of a system...

A hologram that is formed on a recording medium by changing the phase of the illuminating wave in correspondence with the recording exposure. It may be formed by contact printing onto a resist...

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...

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 technique used to generate a phase shift between reference and sample light beams. The phase shift can be performed through the use of a mirror that is moved along the optic axis by a piezoelectric...

An erasable data recording and storage medium that uses a laser to heat the crystalline surface of the disc to a certain temperature, at which it becomes amorphous and records a bit of information;...

A phase-modulated sensor is a type of sensor that uses modulation of the phase of a signal to measure changes in a physical quantity. In such sensors, variations in the phase of the signal are...

A method of coding information in a communications system where the shift in the phase of an electromagnetic wave represents a particular bit or character.

In biology, particularly genetics and evolutionary biology, the phenotype refers to the observable characteristics or traits of an organism, resulting from the interaction of its genetic makeup...

Photocathodes are specialized materials or surfaces that exhibit the photoelectric effect, wherein the absorption of photons leads to the emission of electrons. When photons with sufficient energy...

The term photochemical pertains to chemical processes or reactions that are initiated or influenced by the absorption of light. Photochemical reactions involve the interaction of light, often in the...

An instrument used to detect and measure radiant energy by the formation of a chemical reaction.

A method of producing disks for erasable optical data storage. Information is recorded by a laser beam that generates pits on the surface of the disk while it is being cryogenically cooled. Erasure...

Photoconductive antenna (PCA) is a semiconductor element that generates or detects high-frequency electromagnetic signals. Compact PCAs based on gallium arsenide (GaAs) or indium gallium arsenide...

The effect, present in particular phosphors, that is defined as a transformation in the dielectric constant of a material when illuminated.

A two-electrode, radiation-sensitive junction formed in a semiconductor material in which the reverse current varies with illumination. Photodiodes are used for the detection of optical power and for...

A formulaic description of the linear change of the reciprocal optical dielectric tensor with either stress or strain.

In optics, the double refraction that is produced when stress is applied to a transparent material. Plastics, which are especially photoelastic, can be formed into models of structures that are...

The transformation of incident radiant energy into a photoelectric emission current.

An input device for a computer that detects and reads the data, in the form of punched holes in cards, by light that is transmitted through the holes.

The special cameras, film and other means for forming maps by aerial photography.

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...

The maximum angle of view that can be recorded by a camera. Field is a function of lens focal length and film format.

A form of photometric measurement, often used with light sources that are transparent or fluctuating, in which a photographic plate is used to obtain a record of a source's relative intensities over...

Photolithography is a key process in the manufacturing of semiconductor devices, integrated circuits, and microelectromechanical systems (MEMS). It is a photomechanical process used to transfer...