Photonics Dictionary: C

A compound lens, the dimensions and materials of which have been so chosen that the lens is appreciably free of aberrations.

In rangefinders and height finders, a rotatable or sliding wedge-shaped element used to divert the line of sight precisely to correct errors in the optical system.

An optical wedge of very small angles that admits light while sealing out moisture and dirt and that may be rotated to compensate for the errors in the entire system. Correction windows are sometimes...

An optical element designed to correct each zone of a reflector or refractor for spherical aberration.

The reduction in longitudinal, lateral and secondary chromatic aberrations in a lens or lens system.

An optical material used in place of crown glass to produce lenses with extraordinary correction of chromatic aberrations. Its high coefficient of thermal expansion and its tendency to absorb...

Chromatic aberration is an optical phenomenon that occurs when different wavelengths (colors) of light are refracted by a lens or optical system, leading to a failure to focus all colors to the same...

A closed-loop system that compensates for thermal blooming by optimizing only one parameter: the amplitude of the phase correction.

An optical instrument consisting of a well- corrected objective lens or mirror with a light source and or object/image (i.e. illuminated slit or retical) at its focal plane. Collimators are used to...

An instrument that uses a beam of light to scan a color transparency, and three differently filtered photosensors to record the transmitted beam, as a means of producing three exposed separation...

A microscope eyepiece designed for use with apochromatic objectives. Since apochromatic objectives are undercorrected for lateral color, these eyepieces are overcorrected for that aberration.

An optical element that measures the phase difference between two components of elliptically polarized light to correct for mechanical or optical displacement.

Concave is an adjective used to describe a surface or shape that curves inward or has a hollow or recessed appearance. In the context of geometry or optics, a concave shape is one that curves or...

A device used in broadcast CCD cameras to improve definition in heavily saturated colors by band-limiting the color difference signals after gamma correction.

The simplest lens in which all primary aberrations may be corrected. It consists of two positive crown elements on either side of, and spaced away from, a negative flint element.

The mechanical modification of the shape of the cornea to correct a vision defect.

Recombination of only the light that is correctly dispersed by the first stage of a polychromator through its wide intermediate slit (common during Thomson scattering experimentation), which is...

A method of resampling in which a 16-pixel neighborhood around a given pixel from the original image is used to calculate the final brightness value of that pixel in the corrected image.

A custom optic refers to an optical component that is designed, manufactured, and tailored to meet specific requirements or applications. These optics can include lenses, mirrors, prisms, filters, or...

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape resembling a cylinder. Unlike spherical lenses, which have the same...