Photonics Dictionary: P

An LCD that has pixels with no internal drive transistors.

A crystalline substance in which all planes are parallel, or approximately parallel.

A photonic crystal surface-emitting laser (PCSEL) refers to a type of laser diode that emits light from its surface rather than from the edges. Photonic crystals are periodic nanostructures that...

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 crystal consisting of a substance that has the ability to become electrically polarized and has strong piezoelectric properties. It is cut so as to emphasize the coupling to some distinct...

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

A crystal diode whose rectifying activity is determined by the touching of the crystal to a finely pointed wire surrounded by a material of opposite type.

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,...

A uniaxial, birefringent crystal having an ordinary ray with a higher velocity than the extraordinary ray.

Means of amplifying optical waves whereby an intense coherent pump wave is made to interact with a nonlinear optical crystal to produce amplification at two other optical wavelengths. See parametric...

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...

A microscope equipped with a polarizer, an analyzer and a Bertrand lens to focus on the upper focal plane of the objective. It is used chiefly by mineralogists and crystallographers for...

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...

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 phonon is a quantum of vibrational energy associated with the periodic motion of atoms or molecules in a crystalline lattice. In simpler terms, phonons are quanta of lattice vibrations in a solid...

A light-sensitive resistor in which resistance decreases with increase in light intensity when illuminated. The device consists of a thin single-crystal or polycrystalline film of compound...

A technique proposed for studying the atomic structure of crystals by measuring the interference pattern generated when the crystal is illuminated by a burst of finely tuned x-rays. The resulting...

A photomultiplier tube (PMT) is a highly sensitive vacuum tube that detects and amplifies low levels of light. It is widely used in various applications where high sensitivity, fast response times,...

An infrared detector in which radiation passes through a doped germanium crystal, creating a voltage drop that can be measured in terms of incident intensity.

A structure consisting of a thin film of liquid crystal sandwiched between light-polarizing filters that have received a surface lubricant. Depending on motion, the transducer acts as a highly...

With respect to a crystal, one of the paths or axes that will exhibit a piezoelectric charge when subject to tension or compression.

The interaction between electrical and mechanical stress-strain factors in a material. When piezoelectric crystal is compressed, an electrostatic voltage is generated across it, or when an electric...

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...

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...

Discharge that results when a doped semiconductor crystal with a PN junction is charged with a low-voltage direct current. The dual process depends on excitation caused by electrical energy...

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...

The determination of a substance's identity or quantity through the analysis of its optical rotation. For example, the examination of crystals and polymers under polarized infrared radiation is very...

Polarization refers to the orientation of oscillations in a transverse wave, such as light waves, radio waves, or other electromagnetic waves. In simpler terms, it describes the direction in which...

A filter that polarizes light passing through it. It is possible to fabricate sheets of plastic or gelatin that contain birefringent crystals so oriented as to pass only polarized light. Such sheets...

The process of aligning the crystallites in a piezoelectric material by placing a large DC field across the element at an elevated temperature. The alignment of crystallites results in an increased...

Any of the numerous powders used for grinding and polishing glass, crystal or metal, the chief material being emery and carborundum for grinding, and rouge or the oxides of tin, cerium or other...

A crystal-based device that combines and adjusts the intensities of multiple wavelengths of laser light in order to obtain the desired output wavelength.

The dielectric coefficient parallel to the director in a liquid crystal display (LCD), rather than perpendicular to the director.

A medical imaging device that uses a ring of crystal/photomultiplier tube assemblies encircling the patient to detect gamma rays emitted by positrons colliding with electrons.

A crystalline material with a high electro-optic coefficient, capable of operating at short wavelengths, with applications in laser, optical disc, printing and microwave systems.

A technique used in radiography to determine a crystal's structure by obtaining radiographs of it in powder form, normally by the use of a powder camera that forms an image of the crystal's x-ray...

A plane passing through a crystal that has the optic axis of the crystal and the light ray under consideration.