Photonics Dictionary

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 lens having each of its outer faces curved outward.

Concave and convex spherical mirrors are types of curved mirrors that have surfaces shaped like segments of spheres. These mirrors are commonly used in optics for various applications, including...

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

A converging lens with both surfaces convex.

A lens that has one plane surface and one convex surface.

A cylindrical convex viewing mirror used for viewing distorted pictures formed by photographing the reflections of the objects in a similar type of mirror.

A convex, concave or flat cast iron form that is used to shape a soft mold block of optical components.

A convex lens that brings an incident bundle of rays to a focus to produce intense heat at the focus.

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.

A convex or positive lens that serves to collect energy and direct it into subsequent system optics.

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...

1. In optics, the bending of light rays toward each other, as by a convex or positive lens. 2. Turning in the eyes to view a near object. 3. In a television picture tube, the crossing of the...

Also known as convergent lens or convex lens. A lens that converges an incident bundle of rays to a focus.

A converging lens with one convex and one concave surface.

A lens aberration in which the focal length varies radially outward from the center of the field. It has the effect of making a straight tangential line in the object appear curved in the image,...

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...

A lens with one surface convex and the other concave, the latter having the greater curvature. It also is known as a diverging meniscus lens.

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or film when the lens is focused at infinity. In simple terms, it is the...

A retroreflector that can focus a beam of light, with one planar reflective surface, one spherical and a third that is either planar or convex cylindrical.

A telescope objective with excellent spherochromatic correction, consisting of a meniscus crown and a meniscus flint, both convex to the long conjugate.

In plano work, that property of a surface determining that it is convex and contacts a flat test glass at its center.

An ocular having two planoconvex lenses that are formed from similar glass and that are separated by a space equal to half the sum of their focal lengths. This eyepiece is free of lateral chromatic...

An eyepiece consisting of a planoconvex field lens and a cemented doublet as the eye lens.

A metal tool used to grind lenses with loose abrasive (see diamond cutting tool). The functional surface of the lap is carefully formed to be opposite the curve to be produced on the glass (concave...

Laser optics refers to a broad category of optical components and systems designed for manipulating and controlling laser light. Laser optics play a crucial role in shaping the characteristics of...

A lens is a transparent optical device that focuses or diverges light, allowing it to pass through and form an image. Lenses are commonly used in optical systems, such as cameras, telescopes,...

A lens that has one convex surface and the other concave.

A permanent, transparent, and highly transmissive adhesive capable of withstanding extreme temperatures that is applied to optical surfaces for the purpose of cementing, or the sticking together of...

A telescopic eyepiece that produces a field of view between 40° and 50°. The eyepiece consists of a single element eyelens that is normally plano convex, and a cemented triplet that is...

A metal device of convex or concave curvature to which lens castings or semifinished lenses are cemented with only their edges in contact with the device.

An eyepiece consisting of two planoconvex lenses of the same focal length, with facing convex surfaces.

A form of Cassegrain telescope having a concave hyperbolic primary and a convex hyperbolic secondary. This form permits the simultaneous correction of spherical aberration and coma.

A term used to describe a saddle-shaped -- i.e., convex along one axis, concave along the other -- polished surface, generally an error, whose contours are apparent by the shape of Newton's rings.

The process of grinding the convex surface of a convexo-concave meniscus.

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.

A compound lens consisting of two negative lenses of flint glass. A double-convex lens of crown glass is cemented between the two negative lenses. With this system, it is possible to decrease...