Photonics Dictionary: S

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...

Change of the spatial distribution of a beam of radiation when it interacts with a surface or a heterogeneous medium, in which process there is no change of wavelength of the radiation.

A flat plate having its surface formed into a random pattern by abrasives. Radiation wavelengths that are longer than the scale of the pattern are specularly reflected; shorter wavelengths are...

A defect on a polished optical surface whose length is many times its width. Block reek is a chainlike scratch formed in polishing. A runner cut is a curved scratch caused by grinding. A sleek is a...

The process of grinding the concave surface of a sphero-cylindrical lens.

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 term used to describe a spectacle lens or blank with one surface totally finished.

A projection screen having vertical ribs or flutes set into a plastic surface.

The process of making an abrupt break in a spherical surface on a spectacle lens so that a new center of curvature is set for a portion of the lens. This has the effect of adding a prism to that...

Spatially offset Raman spectroscopy (SORS) is a technique that extends traditional Raman spectroscopy by incorporating measurements at different spatial offsets. This method allows for the selective...

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 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 lens or lens surface that is a combination of a sphere and cylinder.

An instrument for measuring the radius of curvature of a spherical lens or mirror surface. It may consist of a ring resting on the surface, with a micrometer plunger in the middle of the ring to...

The unit solid angle subtended at the center of a sphere by an area on its surface equivalent to the square of the radius; the unit of solid angular measurement, often used in problems of...

A polishing machine with a lens mounted on a wooden stick, allowing a very wide sweep. It is used to polish hemispherical or hyper-hemispherical surfaces.

The fine scratches formed when, in hand centering, the forked stick used to move the lens on the chuck marks the rotating lens surface.