Photonics Dictionary

The cause of some forms of laser injury in which tissue absorbs incident laser light and experiences a damaging rise in temperature. The severity of the damage is dependent on the rate of energy...

Phototoxicity refers to the harmful effects caused by exposure to light, particularly intense or ultraviolet (UV) light, on living cells or organisms. This phenomenon is often associated with the...

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,...

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...

An electron tube having a photocathode for the emission of a photoelectric current.

A photoelectrical relay that uses a phototube as its photoelectric device to open and close an electrical relay; used to activate counters and safety controls.

A photovoltaic cell, commonly known as a solar cell, is a semiconductor device that directly converts light energy into electrical energy through the photovoltaic effect. The photovoltaic effect is...

The generation of a difference in electric potential between two electrodes when radiation is incident on one of them.

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...

A photovoltaic cell usually sensitive to infrared radiation. It may have a copper base and a film of cuprous oxide. When it is irradiated, voltage is produced.

A broadband, visible picosecond probe pulse capable of measuring an entire absorption spectrum in one shot.

A pulse having extremely short duration, about 10-13 to 10-10 s, that is produced by mode locking of wide-bandwidth lasers, such as the organic dye and ruby lasers. Picosecond pulses are used in the...

A method of measuring complex sequential photosynthetic reactions by varying the pulse time and wavelength of light generated by a combination of argon-ion and dye lasers.

A term referring to the cathode-ray tube used in television receivers.

Piezoelectric motion systems are mechanical systems that utilize piezoelectric materials to generate controlled motion or displacement. Piezoelectric materials exhibit the piezoelectric effect, which...

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...

Piezoresistance is a phenomenon in materials science and physics where the electrical resistance of a material changes in response to applied mechanical stress or strain. This change in resistance...

A short length of optical fiber permanently fixed to a component and used to couple power between it and the transmission fiber.

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 type of eyepiece, or the modification of an eyepiece, in which a small hole, without a lens, functions as the eye lens; used in the adjustment and alignment of microscopes.

Pixel binning, also known as pixel merging or pixel combining, is a technique used in digital imaging and camera technology. It involves the combining or grouping of adjacent pixels on an image...

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...

A device used in the sputtering of thin films, in which a magnet system on the back of the cathode deflects the electrons, lengthening the ionization path. The accelerated ions transfer their...

The formula describing the spectral radiant emittance of a perfect blackbody as a function of its temperature and the wavelength of the emitted radiation. where Wλ equals radiation...

A two-dimensional hologram.

The generation of a grating on a flat surface by means of a series of interference fringes formed by a holographic process. See holographic grating.

A wave whose surfaces of constant phase are infinite parallel planes normal to the direction of propagation.

A light beam whose electric vectors all vibrate in a single fixed plane.

A camera system used for microphotography in which the document to be recorded is on a flat bed, perpendicular to the lens axis. The camera head is located above the copyboard on a column and may be...

A plasma accelerator is a type of particle accelerator that uses electric fields and magnetic fields to accelerate charged particles, typically electrons or ions, by exploiting the motion of charged...

An electron beam gun in which plasma that is generated within a low-voltage hollow-cathode discharge serves as the source of electrons.

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,...

Plastic optical fiber (POF) is a type of optical fiber made from transparent plastic, typically polymethylmethacrylate (PMMA) or polycarbonate. Unlike traditional glass optical fibers, which are made...

Plastic optics refers to optical components or systems that are made from transparent plastic materials, as opposed to traditional optical components made from glass or other materials. Plastic...

Any crystalline material whose length is much less than its measured diameter.

A semiconductor material used in photodetectors, sensitive in the infrared up to 5 µm.

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...

A Pockels cell, also known as an electro-optic modulator, is an optical device used to control the polarization of light by applying an electric field. It is named after the physicist Friedrich Carl...