Definitions: I

A telescope that transmits, enlarges and converts infrared images.

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...

A thermistor that uses a semiconductor that is sensitive to infrared radiation to measure the radiation's intensity.

A vidicon that has a photoconductive surface that can be excited by infrared radiation.

1. A thin parallel plate of material that transmits in the infrared region. See infrared optical material. 2. A spectral region (of the infrared) in which the atmosphere transmits.

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...

A semiconductor device with a semiconductor junction in which infrared radiant flux is nonthermally produced when a current flows as a result of applied voltage.

An InGaAs photodiode refers to a photodetector device that is constructed using a semiconductor material composed of a combination of indium (In), gallium (Ga), and arsenic (As). The term InGaAs...

Broadening of a laser's spectral linewidth when the resonance frequencies of the atoms (or molecules) of the medium are not homogeneous on the same transition. An example is Doppler broadening.

The use of two lasers as a master-slave pair in order to control frequency and prevent chirp. When light from the master is injected into the slave, the slave becomes locked to the same frequency as...

A semiconductor diode operating in either a coherent or incoherent mode that is used as a near-infrared or visible source in triggering light-activated devices.

A method of producing high-quality plastic optics in large volumes by injecting the heated, liquified plastic at high pressure into a tooled mold with polished chromium stainless steel inserts to...

The use of a small ultrastable master oscillator (a diode-pumped Nd:YAG laser) to achieve single-frequency operation of a large pulsed Nd:YAG host laser, providing improved bandwidth and temporal...

A process by which a plastic cell is molded around a glass lens or lenses to create a mount, eliminating the metal barrel and the need for glass-to-metal seals.

In a camera, the movement of one or more lenses behind the front lens, rather than of the front lens itself, to bring the subject into focus. Because internal focusing does not require the front lens...

I/O stands for input/output. In computing, it refers to the communication between a computer system or program and its external environment, including peripherals, storage devices, networks, and...

The total optical power loss caused by the insertion of an optical component such as a connector, splice or coupler into a fiber optic system. See attenuation.

The horizontal distance between the 90° meridian of a bifocal lens and the geometrical center of the segment.

A method that produces low-loss optical fibers. A glass tube rotates while reactants pass through the tube and heat is externally applied by a burner that traverses the tube. The oxidizable vapors in...

A small round mirror on the end of a handle used for viewing inside an inaccessible cavity.

Instantaneous field of view (iFOV) is a term commonly used in the context of remote sensing, imaging systems, and optical instruments. It refers to the specific portion of a scene that an optical...

The tendency to adjust an instrument such as a microscope so that the viewed image appears much closer than infinity.

With respect to color photography, the measurement of the way the color film modulates the radiant flux in the optical system containing the film.

A reflection hologram using multiple color lasers that integrates various graphical techniques to allow the display of three-dimensional images of live objects in motion, as well as outdoor scenes,...

Multiple, interconnected circuit elements, contained on or in a common substrate, that function as a unit and not separately.

An infrared detector mounted directly on the cold finger of the Dewar cooler rather than at the interface of Dewar and cooler, resulting in decreased size and power consumption and greater...

Also known as integrated exposure. A measurement of light from sources that vary rapidly with time, defined as the integral of instantaneous power and time and expressed as units per second.

A type of laser for which a large number of the components can be fabricated in or upon a single substrate.

An optical circuit, either monolithic or hybrid, composed of active and passive components, used for coupling between optoelectronic devices and providing signal processing functions.

A thin-film device containing miniature optical components connected via optical waveguides on a transparent dielectric substrate, whose lenses, detectors, filters, couplers and so forth perform...

Integrated photonics is a field of study and technology that involves the integration of optical components, such as lasers, modulators, detectors, and waveguides, on a single chip or substrate. The...

A set of international standards by which a single telecommunications channel is used to transmit voice and data simultaneously.

A hollow sphere coated internally with a white diffusing material and provided with openings for incident beam, specimen and detector used for measuring the diffuse reflectance or transmittance of...

Integration time, in the context of optics, imaging systems, and sensor technology, refers to the duration over which a sensor collects and accumulates incoming light or signal. It is a crucial...

An intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an image intensifier and a charge-coupled device (CCD) sensor to achieve...

A CCD image sensor that uses a proximity-focused image intensifier to provide greater sensitivity at low light levels.

A standard direct-readout vidicon tube linked by fiber optics to an intensifier for increased sensitivity.

Flux per unit solid angle.

An interferometer that functions by first detecting the light striking each aperture and then combining the two detector outputs. With an intensity interferometer, the primary collectors need not be...

The process in which the electron beam of a cathode-ray tube varies in intensity in accordance with the magnitude of the signals it receives.

A type of fiber optic sensor that responds to a change in the intensity of received light caused by the displacement or other phenomena being measured.

A lens that has a mount, usually bayonet or screw type in design, that can be used on a camera in place of lenses with the same mounting. This allows one camera body to be used with lenses of...

That angle found between a pair of adjacent faces of a crystal.

1. The additive process whereby the amplitudes of two or more overlapping waves are systematically attenuated and reinforced. 2. The process whereby a given wave is split into two or more waves by,...

Color resulting from the interference between two light beams.

A filter that controls the spectral composition of transmitted energy partially by the effects of interference. Frequently, these filters are made up of thin layers of metals and dielectrics,...