Photonics Dictionary: P

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

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

Passive optical components are devices or elements used in optical systems that do not require external power or active control to perform their function. These components manipulate light signals...

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...

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...

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 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...

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...

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...

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.

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.

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...

Photoluminescence is a phenomenon in which a material absorbs photons (light) at one wavelength and then re-emits photons at a longer wavelength. This process occurs when electrons in the material...

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...

A photonic engine refers to a device or system that utilizes photonics, or the science and technology of generating, controlling, and detecting photons (particles of light), to perform various...

A photonic integrated circuit (PIC) is a compact and integrated device that incorporates multiple photonic components and functions on a single chip, similar to the way electronic integrated circuits...

The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The science includes light emission, transmission, deflection, amplification and...

Photoplethysmography (PPG) is a non-invasive optical technique used to detect changes in blood volume in tissues. It measures variations in light absorption caused by the pulsatile nature of blood...

A document-transmitting process that uses a cylinder that rotates the document to be scanned and detected by a photoelectric cell. The cell transforms the light into electrical energy that may be...

A tachometer consisting of a light source, rotating perforated wheel and phototransistor to measure the rates of rotation of components. The phototransistor counts the flashes formed when the wheel,...

Piezoelectric transducers are devices that utilize the piezoelectric effect to convert electrical energy into mechanical vibrations or vice versa. The piezoelectric effect is a property exhibited by...

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...

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...

Pluggable optics, also known as pluggable transceivers or optical transceivers, are modular devices used in optical communication systems to transmit and receive data over optical fibers. They are...

In digital image processing, a subcategory of frame processing that transforms pixel brightness and contrast through use of a mapping function. Point processing can be single-image (simple contrast...

An optical device capable of transforming unpolarized or natural light into polarized light, usually by selective transmission of polarized rays.

A substance that transmits the infrared, but which is too delicate or fragile to be used in the form of a single crystal. Instead, the pure material is finely ground, pressed to the required shape,...

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....

Power modulation refers to the intentional variation of power levels in a signal, often in the context of electronic communication systems. This modulation technique is used to encode information...

An accurately produced hole of any size and shape that is used as a masking device in an optical system. Pinhole apertures of accurate diameters often are produced by laser beam penetration or by...

A prism is a geometric optical element with flat, polished surfaces that refract light. It is typically a solid, transparent object with at least two flat surfaces that are inclined relative to each...