Photonics Dictionary

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...

An interferometric method for describing the surface shape of large coated or uncoated optical flats. The procedure uses a commercially available small-aperture phase-shifting interferometer for...

The circle that contains the slit, grating and primary astigmatic focus of a concave diffraction grating.

1. In the geometric sense, an abbreviation for the term "sagitta,'' the height of a curve measured from the chord. and it is exact for a parabola. 2. Conforming a sheet of glass to a...

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 saturable absorber is a type of optical device that exhibits variable absorption properties depending on the intensity of incident light. In essence, it becomes less absorbent as the light...

1. The decrease of the absorption (or gain) coefficient of a medium near some transition frequency when the power of the incident radiation near that frequency exceeds a certain value. As long as the...

1. A device used to trace out an object and build up an image. One of the most common of these types is video scanning. The scanning takes place inside the television tube as electrons, guided by...

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

The angle between the initial and final paths traveled by a scattered particle or photon.

A camera that consists of a concave spherical mirror with an aspheric plate situated at the center of curvature of the mirror. The purpose of the plate is to correct the spherical aberration of the...

A scientific CMOS (complementary metal-oxide-semiconductor) camera is a type of digital camera specifically designed for scientific imaging applications. It employs CMOS sensor technology, which...

Scientific complementary metal-oxide semiconductor (sCMOS) refers to a type of image sensor technology specifically designed for scientific and industrial imaging applications. Unlike traditional...

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...

A nonlinear label-free imaging technique commonly used during surgical procedures for the visualization of collagen fibers and muscle tissue (myosin) with submillimeter resolution. During the...

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...

An aberration that remains after primary color is corrected. Primary color causes the back focus of a lens to vary with wavelength; for example, blue light comes to focus closer to the lens than...

An optically bistable device used for photonic switching, constructed of a multiple quantum well biased by an external voltage, which creates an external field that shifts the wavelength of the onset...

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...

A polarizing beamsplitting prism similar in design to the Rochon prism. However, the Senarmont transmits the extraordinary ray without deviation and deviates the ordinary ray due to the orientation...

A device used in measuring attenuation in optical fiber. The loss caused by the bends in a short reference length of fiber approximates that of a much longer fiber under test.

A compact high-pressure light source in which an electrical discharge between electrodes spaced no more than 12 mm apart occurs in a xenon or other gas medium, providing a visible light resembling a...

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...

Single-molecule Förster resonance energy transfer (smFRET) is a specialized technique in biophysics and molecular biology used to study the distances and dynamic interactions between two...

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...

Solid-state laser geometry in which the standard rod is replaced by a slab of laser material. Often called total-internal-reflection face-pumped laser (TIR-FPL).

A crystal, glass, or quartz slicing and cutting machine is a specialized piece of equipment used in the manufacturing process to precisely cut and slice materials such as crystals, glass, and quartz...

An optical projection device designed to project positive color transparencies onto a screen for viewing.

A form of liquid crystal in which flow does not take place in the usual manner. When examined with polarized light, the substance often forms drops that display a series of fine lines. X-ray...

The incident ray, the normal to the refracting surface at the point of incidence of the ray at the surface, and the refracted ray all lie in a single plane. The ratio of the sine of the angle between...

The letter form used on visual performance test charts. The overall letter height is equal to five times the thickness of individual strokes. Normal 20/20 vision is represented by the ability to...

Term applied to radiation composed of particles or photons that will not easily penetrate a material because of their low energy levels.

A device for converting sunlight into electrical energy, consisting of a sandwich of P-type and N-type semiconducting wafers. A photon with sufficient energy striking the cell can dislodge an...

An optical system that is designed to produce a high temperature in a specified area by the optical direction and concentration of solar radiation on that area. The system usually consists of a...