Photonics Dictionary

Terahertz (THz) refers to a unit of frequency in the electromagnetic spectrum, denoting waves with frequencies between 0.1 and 10 terahertz. One terahertz is equivalent to one trillion hertz, or...

A device used to detect elevation, pyramid and resolution errors in prisms and other components by bringing them into contact with the three highly polished, flat, perpendicular surfaces that form...

A transparent block shaped accurately to reverse curvatures of the components it is used to test. By contacting an accurately finished negative lens shape with a newly made positive, the conformity...

Thermal interface materials (TIMs) are substances or compounds used to enhance the thermal conductivity between two surfaces in contact. These materials are primarily employed in electronic devices,...

A term referring to various processes for forming visible images outside of a camera to be photographed on ordinary film. Unlike regular infrared photography, thermal photography is an indirect...

Thermography is a technique that involves the use of an infrared imaging device, called a thermal camera or infrared camera, to detect and visualize the infrared radiation emitted by objects. This...

A microcircuit whose passive components consist of a ceramic-metal combination deposited on a given substrate by screening and firing processes.

Successive layering of resistive, dielectric and conductive inks on a substrate by a type of screening process.

A type of recording material, usually a photodielectric polymer, offering in situ development mechanisms because of its density storage capabilities, high diffraction efficiencies and excellent noise...

A circuit whose passive components are deposited on a given substrate by sputtering or vacuum processes.

Thin-film coatings are layers of material applied to the surface of an object or substrate, typically to modify its optical, electrical, or mechanical properties. These coatings are composed of thin...

Thin-film deposition equipment refers to machinery and tools used in the process of depositing thin layers of material onto a substrate surface. This technique is commonly employed in various...

Thomson scattering is a phenomenon in physics where electromagnetic radiation, such as light, is scattered by charged particles. It is named after the British physicist J.J. Thomson, who first...

Referring to compound semiconductor materials combining one element that has three valence electrons with one or more that have five. Examples include gallium arsenide and indium antimonide. (III-V).

Three-photon microscopy is an advanced imaging technique that belongs to the family of multi-photon microscopy methods. It is used in biological and medical research to capture high-resolution images...

The time domain is a concept used in signal processing and analysis to describe signals in terms of their behavior over time. In the time domain, signals are represented as functions of time, showing...

Time-correlated single photon counting (TCSPC) is a technique used in photon counting applications, particularly in the field of experimental physics, biophysics, and fluorescence lifetime imaging...

Time-lapse optical coherence tomography (OCT) refers to a medical imaging technique that captures a series of sequential OCT scans over time, allowing for the dynamic observation and monitoring of...

A laser fitted with up to eight optical fibers that transmit the energy to different workstations in turn.

A time-to-amplitude converter (TAC) is an electronic circuit that converts a time interval between two events into an amplitude or voltage signal. TACs are commonly used in various scientific and...

Tip-enhanced Raman scattering (TERS) is a powerful technique that combines Raman spectroscopy with the enhanced spatial resolution provided by a sharp metallic or dielectric tip. TERS allows...

A spectroscopic technique that combines the high chemical specificity of Raman scattering and signal sensitivity provided by surface plasmon resonance enhancement, with the nanoscale spatial...

The study of the optical properties of living tissue. Increased understanding of the behavior of light in this varied, turbid medium, especially its scattering and absorption characteristics, is...

The determination of the degree to which a manufactured component can deviate from its ideal specifications of material and geometry without impairing its performance.

Topological photonics is a branch of physics and optics that explores the application of topological concepts to the behavior of light in photonic systems. Drawing inspiration from the field of...

Topology is a branch of mathematics that focuses on the properties of space that are preserved under continuous deformations, such as stretching, crumpling, and bending, but not tearing or gluing....

Image displacement by a decentered lens, rotated on a chuck whose axis of rotation passes through the geometrical center of the rim of the lens, when the light source is at an infinite distance. It...

Total internal reflection fluorescence (TIRF) microscopy is an advanced fluorescence microscopy technique that leverages the principle of total internal reflection to selectively illuminate and image...

A naturally occurring crystalline mineral that has the property of polarizing transmitted light. It is little used now that the Polaroid sheet is available.

Effect whereby two electrons lose synchronism with the accelerating field and are lost during synchronous radiation. The effect is produced by the scattering of the electrons that are oscillating in...

1. The process of following an object's movement; accomplished by focusing a radar beam on the reticle of an optical system on the object and plotting its bearing and distance at specific intervals....

A transducer is a device or component that converts one form of energy into another. It is commonly used in various fields, including electronics, acoustics, and instrumentation, to facilitate the...

A process used to control thickness and parallelism precisely during the production of plane-parallel plates. Elements are cemented to a blocking tool and their upper surfaces are polished. A second...

A method of measuring total hemispherical emissivity of the plane surface of a solid that consists of thermally isolating a specimen of the material inside a vacuum, preheating it slightly above the...

The process whereby a quantum mechanical system alters from one energy level to another. During this process, energy is emitted or absorbed, and it usually takes the form of photons, phonons, or...

The central wavelength range of a transmitter based on the worst-case scenarios of temperature, manufacturing and other variations.

Capable of transmitting light with little absorption and no appreciable scattering or diffusion.

Multiple scattering method used in biological analysis in which approximations yield simple, explicit solutions, at least for slab geometry. The approximations are usually differential equations...

In the context of optics and lasers, a transverse mode refers to a specific spatial pattern of the electric field within the cross-section of a laser beam. These modes represent the different...

The method for measuring the index profile of an optical fiber or preform by illuminating it coherently and transversely to its axis, and examining the far-field radiation pattern.

A measuring instrument composed of a microscope and reticle, and mounted on a calibrated slide mechanism. May be used accurately to determine the distance between objects being viewed.

A method of measuring distance by recording a single scene from two points of perspective. Surveying instruments can be used; in autofocus systems, rangefinders and three-dimensional imaging systems,...