Photonics Dictionary: C

A lens, one surface being a cartesian oval, that produces an aplanatic condition.

A system that uses both reflection and refraction to achieve its focal power. While the relative powers of the lenses and mirrors vary from system to system, the use of the reflective surfaces to...

An optical system in which the only image-forming elements are curved-surface mirrors; e.g., a Cassegrain lens system.

A CCD image sensor, or charge-coupled device image sensor, is a type of electronic device used to convert optical images into electronic signals. It is a key component in digital cameras, camcorders,...

The surface of an element of a compound lens that will produce the cemented interface. The curves of this interface are called inside curves. To facilitate cementing, the two inside curves should...

The center of the sphere of which the surface of a lens or mirror forms a portion. Each curved surface of a lens has a center of curvature; the surfaces may be convex or concave.

The surface curvature designed to reduce the marginal error found in the periphery of a spectacle lens.

A lens system in which the centers of curvature of all surfaces fall on a common axis.

In a perfectly centered lens, the mechanical axis (defined by the ground outside the diameter of the lens) is made to be exactly coincident with the optical axis (defined by a line through the...

A charge-coupled device (CCD) is a type of electronic image sensor used in various imaging devices, including digital cameras, camcorders, and scientific instruments. It consists of an integrated...

The mark formed when the movement of the lens over the face of the centering chuck abrades the surface.

The limited light-gathering area of an optical system. The area is normally restricted to an edge or outer surface of an individual component. Also known as free aperture or objective aperture. The...

1. A constituent part. It may consist of two or more parts cemented together, or with near and approximately matching surfaces. 2. The projection of a vector on a certain coordinate axis or along a...

A lens composed of two or more separate elements of optical glass that may or may not be cemented together. The surfaces of the elements are shaped to reduce or eliminate the aberrations inherent in...

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 lens with one concave surface and one convex surface; synonymous with meniscus.

A lens having surfaces whose centers of curvature coincide.

A lens with a surface that is a cone instead of the usual sphere.

A converging lens with one convex and one concave surface.

Convex is an adjective used to describe a surface or shape that curves outward, bulges, or has a rounded and outwardly extending appearance. In the context of geometry or optics, a convex shape is...

A corner cube, also known as a corner reflector or retroreflector prism, is a type of optical device used to reflect light or electromagnetic waves back towards their source with minimal deviation in...

The concave portion of a surface, formed on a blank, on which the disk of higher refractive glass will be fused to form a multifocal spectacle lens.

The measure of departure from a flat surface, as applied to lenses; the reciprocal of radius. Applies to any surface, including lenses, mirrors and image surfaces.

A lens aberration that causes a flat object surface to be imaged onto a curved surface rather than a plane.

In a cylindrical lens, the meridian parallel to the generating lines of the cylindrical surface. In a toric lens, the cylinder axis is the axis of the equivalent cylindrical surface that has been...