Photonics Dictionary: S

Correction of an optical system at four separate wavelengths. This correction, longitudinal and lateral, is possible with the help of three selected special glasses.

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 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...

An aspheric plate placed at, or near, the center of curvature of a spherical reflector and used to correct for spherical aberration.

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...

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...

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...

A term used to describe a convex surface having too short a radius of curvature. To correct this condition, material is cut from the outer portion of the polishing tool.

Spectral flow cytometry is an advanced flow cytometry technique that expands the capabilities of traditional flow cytometry by utilizing spectral information from fluorochromes to enhance...

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 derived from the Cooke triplet anastigmat, but with one of the crown elements split in two, resulting in improved speed and correction of aberrations.

A phenomenon that causes the details in an image to appear at a spatial frequency higher than that at which the contrast first drops to zero. A phase reversal will accompany this phenomenon, often...

A liquid crystal display using the material in its supertwisted nematic phase; the birefringence of the liquid crystal results in a characteristic yellow or blue color, unless corrected.