Photonics Dictionary: I

Infrared radiation absorbed by crystals as a result of the excitation of lattice vibrations in which ions having opposite charges move relative to one another. These vibrations take place in a narrow...

Sharp and narrow absorption lines found in the spectra of stars. They result from the absorption of a part of a star's emittance by interstellar gases.

An absorbing coating medium between fibers, used in some fused fiber optic plates to absorb unwanted light. Such coatings are sometimes called EMA (extramural absorption).

In the context of optical materials, the term "impurity level" refers to the presence of foreign atoms or molecules within the material that deviate from its regular or intrinsic composition. These...

Indium phosphide (InP) is a compound semiconductor material composed of indium (In) and phosphorus (P). It belongs to the III-V group of semiconductors, where elements from groups III and V of the...

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible spectrum of light. These detectors are utilized in various applications,...

A filter exhibiting transparency, absorption or reflectance characteristics specifically for spectral control of wavelengths longer than 700 µm.

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating infrared (IR) radiation within the infrared spectrum. These lenses are used in...

The measurement of the ability of matter to absorb, transmit or reflect infrared radiation and the relating of the resultant data to chemical structure.

Used to detect radiation from the infrared region. The functional process includes absorption of infrared radiation, which causes a temperature change, consequently altering the physical properties...

Infrared (IR) refers to the region of the electromagnetic spectrum with wavelengths longer than those of visible light, but shorter than those of microwaves. The infrared spectrum spans wavelengths...

With reference to absorbance, absorptance, transmittance and the like, the processes occurring within a specimen between the entry and exit surfaces.

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.

A nonoptical surface, within lenses and lens mounts, that contributes largely to flare by reflecting light into the image space. As a result, such surfaces, so located, are finished with a dull...

The absorption of a photon raising an electron across the forbidden gap from valence to conduction band of the semiconductor where conductivity is increased and incident radiation may be measured.

Collisional absorption of energy that occurs in inertial confinement fusion systems when hydrodynamic expansion of the plasma causes an electron passing through the field of an ion to absorb...

A spectroscopic technique in which an excitation band absorbs laser energy resulting in an electronic transition. The isotopic species may then be measured using a time of flight mass spectrometer....