Photonics Dictionary: S

X-rays emitted by a substance that formerly has been exposed to x-rays. The properties of the substance determine the frequency of the rays.

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 specific type of photographic plate designed with only a small amount of gelatin to function in the extreme ultraviolet and in positive-ray analysis.

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...

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 line formed by the principal (center) ray of an oblique bundle of rays.

Seidel aberrations refer to a set of monochromatic aberrations in optical systems, named after the German mathematician and physicist Ludwig von Seidel. These aberrations describe deviations from...

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 variation of tomography, which is a means of visualizing any one of a large set of parallel planes in the patient. A series of x-ray pictures taken from different angles results in developed...

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...

Any ray through an optical system that is not a meridional ray. The plane created by a refracted skew ray does not contain the optical axis.

The investigation of microstructures by an instrument that generates a narrow, highly collimated beam of x-rays.

An array of active optical devices (modulators, laser diodes and/or detectors), each of whose electrical inputs or outputs are directly connected to electronic logic circuits, which also are a part...

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...

A transmission interference microscope that produces interference patterns of a sample by using birefringent plates that split a polarized beam of light into ordinary and extraordinary rays, then...

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...

A ruggedized scintillation counter used in oil well logging. The cylindrical housing contains a gamma ray source, a crystalline scintillator and a photomultiplier tube. As the sonde is drawn through...

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...

When, for example, a beam of monochromatic light passes through a diffraction grating, the emergent rays that have remained undeviated are included in the zero spectral order. The light flux in the...

A spectral signature, in the context of remote sensing and spectroscopy, refers to the unique pattern or characteristic spectral response of a material or object across different wavelengths of the...

A high-contrast transparency of the gas sought, or an array of exit slits that correlates with some features of the spectrum. No standardized formula for positioning, number or thickness has been...

A spheric lens, also known as a spherical lens, is a type of optical lens with at least one surface that is part of a sphere. This means that the lens surface is curved in a symmetrical manner,...

Spherical aberration is an optical aberration that occurs when light rays passing through a lens or curved optical surface do not converge or diverge to a single focal point. Instead of focusing to a...

A memory system composed of a stack of holographic plates, a mode-locked laser and a rapid detector array. Ultrashort laser pulses are used to extract information from the stack. In this way, storage...

The determination of axially symmetric and asymmetric refractive-index distributions by use of interferometry carried out on the basis of the approximation of a straight path of rays passing through...

An image of an object that appears above the object's true position as the result of abnormal refraction of the image rays by the atmosphere.

An acoustic wave that propagates along the surface of a solid and decays exponentially with substrate depth. Also called a Rayleigh wave, it has both longitudinal and transverse (shear) components....

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or positrons, in a closed, circular or elliptical path. The name synchrotron...

Radiation emitted by electrons when they travel in circular orbits at speeds close to that of light. Synchrotron radiation occurs in the x-ray and ultraviolet regions of the spectrum. Once considered...