Photonics Dictionary

The transition cross section constant coefficient which defines the transition probability of absorption from ground to a higher level within a given atomic or molecular species. The transition...

Mount attached to a camera or camcorder which allows the user to attach a microphone or flash unit.

The coefficient Å in Angstrom's formula for the dispersing coefficient for dust present in the atmosphere. The formula is expressed as S × Ål-B where l represents wavelength and B...

The rate of diminution of average optical power and the sum of the scattering and absorption coefficients.

Fraction of light counter propagating collinear with the incident source. Processes considering backscattering are Raman, Brillouin, Rayleigh and Mie.

The law stating that the amount of chemical change produced is proportional to the amount of light absorbed. Actually, the change is also dependent on the intensity of light -- a fact named the...

The coefficient termed by Callier as the ratio between the density of photographic negatives measured by parallel light and that measured by diffuse light, due to scattering effects. This effect is...

A technique of using dyes during endoscopy to improve tissue differentiation. Dyes such as methylene blue, Toluidine blue and Lugol's solution all have the ability to stain particular types of cells....

A numerical representation of the rate at which a material will exhibit dimensional changes as a direct result of changes in temperature.

A plane mirror mounted on a polar axis that lies parallel to the plane of the mirror. When the mirror is rotated once in 48 hours, celestial objects can be made to appear stationary and are...

A laser warning and countermeasure system containing a sensor that indicates the direction of a laser beam, and analytical instruments to determine pulse code, repetition frequency and wavelength.

Three proportional coefficients labeled Am, Bmn, and Bnm, that respectively characterize the rate of spontaneous emission, induced emission, and absorption of radiation by an atom, ion or molecule.

The ejection of electrons from the surface of a solid by the absorption of a sufficient amount of photons.

A crystal capable of being polarized in the reverse direction when an electric field is applied.

The region of a ferroelectric crystal where spontaneous polarization is uniformly directed.

Film in which electric polarization is reversible when influenced by an electric field.

Ferroelectric materials are a type of dielectric materials that exhibit spontaneous electric polarization, meaning they possess a permanent electric dipole moment even in the absence of an external...

The phenomenon whereby certain crystals exhibit spontaneous electric polarization. It is analogous with ferromagnetism.

A system that transmits and receives identification codes to facilitate the discrimination between enemy and friend in a tactical situation.

The effect in which photons are absorbed and excite the electrons; the electrons move from the valence band to the conduction band (intrinsic photoeffect), from the valence band to impurity levels or...

The creation of free electrons within a solid by the absorption of a sufficient amount of photons. The effect produces an increase in the conductivity of the solid.

The photoemission that would occur if a crystal were pure and its structure perfect.

The changing of the kinetic energy of a mobile electron into radiant energy, as in formation of x-rays.

The resulting contraction or expansion of a piezoelectric crystal along an electric axis when the crystal is under the influence of an electric field in the same direction.

A two-stage illuminating system for a microscope in which the source is imaged in the aperture of the substage condenser by an auxiliary condenser, and the substage condenser in turn forms an image...

A visual, single-unit spectrophotometer with a biprism and a Wollaston prism. The Wollaston prism polarizes coincident images of the two halves of the entrance aperture.

Refers to micron-size complex machines that have physical dimensions suitable for the fabrication of optical switches for use in state-of-the-art communications networks.

Equipment that supports microscopic live-cell imaging by managing the gas, media perfusion, temperature and other factors to which a sample is exposed. While reducing the negative impacts these...

Pertaining to radiation or particle emission, whereby the emission is produced with minimal energy spread.

Pertaining to a device that responds to optical power, emits or modifies optical radiation, or utilizes optical radiation for its internal operation. Any device that functions as an...

A monolithic device containing both photonic and electronic sources, detectors, modulators, etc., on a single semiconductor substrate.

A transistor that uses an electro-luminescent source, a transparent base and a photoelectric collector.

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light and its interactions with different materials. The term "optoelectronics" is...