Photonics Dictionary

A resonator is a device or system that exhibits resonance, which is a phenomenon that occurs when an external force or stimulus is applied at a specific frequency, causing the system to oscillate...

Retroreflection is a phenomenon in optics where light is reflected back toward its source, typically in a direction nearly parallel to the direction from which it originated. This occurs due to the...

Retroreflectivity refers to the property of a surface or material to reflect light back to its source, regardless of the angle of incidence. Unlike most surfaces that scatter light in various...

A retroreflector is an optical device or structure that reflects incident light or electromagnetic waves back to their source, regardless of the direction from which the light approaches. Unlike...

Rhodamine refers to a family of fluorescent organic dyes that are widely used in various fields, including biology, chemistry, medicine, and materials science. These dyes are known for their bright...

A ring laser gyroscope (RLG) is a type of gyroscope that uses laser light to detect and measure changes in orientation. It operates based on the Sagnac effect, which is a fundamental principle of...

A Risley prism, also known as a Risley prism pair or Risley rotating prism, is an optical device used for controlling the direction of a laser beam or other optical beam by independently rotating two...

Robotic arms, also known as robot arms or manipulator arms, are mechanical devices designed to mimic and perform the functions of human arms. They consist of multiple articulated segments, joints,...

Rockwell hardness (Rc) refers to a method for measuring the hardness of a material, primarily metals, using an indentation test. It is named after the Rockwell scale, which was developed by Stanley...

A roughening laser is a laser-based surface modification technique aimed at altering the surface texture of a material to achieve specific properties such as enhanced adhesion, light diffusion, or...

A Rugate filter is a type of optical filter that is designed to have a continuously varying refractive index profile throughout its thickness, rather than the discrete layers found in traditional...

Sagnac interferometry is a technique used to measure rotation or angular velocity based on the principle of interference. It relies on the Sagnac effect, named after the French physicist Georges...

Sapphire crystal refers to a transparent, single-crystal form of aluminum oxide (Al2O3) known as corundum. It is one of the hardest known materials, second only to diamond on the Mohs scale of...

Sapphire optical fiber is a type of optical fiber made from single-crystal sapphire, which is a form of aluminum oxide (Al2O3) that is highly transparent in the infrared region of the electromagnetic...

A sapphire window refers to a transparent optical component made from sapphire crystal. Sapphire is a single-crystal form of aluminum oxide (Al2O3) that is highly prized for its exceptional optical...

Sapphire refers to a crystalline form of aluminum oxide (Al2O3) that is used in various optical and photonic applications due to its exceptional optical, mechanical, and thermal properties. Sapphire...

A scanning electron microscope (SEM) is a powerful imaging instrument used in scientific research, materials characterization, and various industrial applications. Unlike traditional optical...

Scanning electron microscopy (SEM) is an advanced imaging technique used in microscopy to obtain high-resolution, three-dimensional images of the surfaces of solid specimens. SEM achieves this by...

A Schottky diode is a type of semiconductor diode characterized by its low forward voltage drop and fast switching speed. It is formed by the junction of a metal and an n-type semiconductor, creating...

A scintillation crystal, also known simply as a scintillator, is a material that emits light when it interacts with ionizing radiation such as gamma rays, x-rays, or charged particles. The emitted...

A scintillation detector is a radiation detection device that utilizes scintillation crystals to detect and measure ionizing radiation, such as gamma rays, x-rays, or charged particles. It consists...

Second-harmonic generation (SHG) is a nonlinear optical process that occurs when two photons with the same frequency combine within a nonlinear material, resulting in the generation of a new photon...

Second-order nonlinear optical properties refer to a class of phenomena exhibited by certain materials in response to intense light, typically in the realm of optics and photonics. Nonlinear optical...

Selective laser melting (SLM) is an additive manufacturing (AM) or 3D printing technology that belongs to the powder bed fusion category. SLM is primarily used for metal additive manufacturing, where...

Self-phase modulation (SPM) is a nonlinear optical phenomenon that occurs when an intense laser beam passes through a medium, causing a change in the phase of the light due to its interaction with...

Servo motion is the controlled motion of a mechanical system achieved through the use of a servo motor, which utilizes feedback mechanisms to ensure accurate positioning, speed, and acceleration....

A servo, short for servomechanism or servo motor, is a closed-loop control system that precisely controls the position, velocity, or acceleration of a mechanical component, typically in response to...

The Shack-Hartmann wavefront sensor is an optical device used for measuring the wavefront aberrations of an optical system. It is widely used in adaptive optics systems to correct distortions and...

Short wavelength infrared (SWIR) refers to the portion of the infrared spectrum that encompasses wavelengths roughly between 1,000 and 3,000 nanometers (nm). In the electromagnetic spectrum, infrared...

Silicon carbide (SiC) light-emitting diodes (LEDs) are semiconductor devices that emit light when an electric current is applied to them. These LEDs are made using silicon carbide as the...

A silicon photodiode is a semiconductor device that converts light into an electrical current. It is a type of photodetector specifically designed for detecting and measuring light intensity. Silicon...

A single-photon avalanche diode (SPAD) is a specialized type of photodetector designed to detect extremely weak optical signals, down to the level of single photons. SPADs are widely used in...

A singlet lens is an optical lens made from a single piece of material, typically glass or plastic, with one or both surfaces being spherical or aspherical. It is the most basic type of lens used in...

A singulated die refers to an individual semiconductor chip that has been separated or singulated from a larger wafer. This term is commonly used in the semiconductor manufacturing industry. ...

Sisyphus cooling is a technique used in atomic physics to achieve ultracold temperatures of atoms or molecules by exploiting the periodic motion of particles in optical traps or lattices. The name...

A skyrmion is a topologically stable, vortex-like configuration of spins in a magnetic material. These configurations are characterized by a swirling pattern where the direction of the magnetic...

In photonics, a slot modulator refers to a type of optical modulator that operates based on the principle of modifying the optical properties of a slot waveguide. A slot modulator is an optical...

Smart microscopy refers to the integration of advanced technologies, such as artificial intelligence (AI), automation, and machine learning, into conventional microscopy techniques to enhance imaging...

A solar simulator is a device used to replicate the spectrum and intensity of sunlight in a controlled environment for testing and research purposes. Solar simulators are employed in various...

A solid-state drive (SSD) is a storage device that stores data electronically using solid-state memory chips. Unlike traditional hard disk drives (HDDs) that use spinning disks and mechanical...

A solid-state laser is a type of laser that uses a solid gain medium (as opposed to a liquid or gas) to produce coherent light. The term "solid-state" refers to the fact that the active medium, where...

A spaser (surface plasmon amplification by stimulated emission of radiation) is a nanoscale device that generates coherent optical radiation at nanometer-scale dimensions. It is analogous to a laser...

A spatial light modulator (SLM) is an optical device that modulates or manipulates the amplitude, phase, or polarization of light in two dimensions, typically in the form of an array. SLMs are...