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A burning apparatus consisting of two biconvex lens. A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction.A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis.
Different kinds of camera lenses, including wide angle, telephoto and speciality. A camera lens (also known as photographic lens or photographic objective) is an optical lens or assembly of lenses (compound lens) used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.
A telephoto lens, also known as telelens, is a specific type of a long-focus lens used in photography and cinematography, in which the physical length of the lens is shorter than the focal length. [ 1 ] : 93 This is achieved by incorporating a special lens group known as a telephoto group that extends the light path to create a long-focus lens ...
Contact lenses are typically inserted into the eye by placing them on the pad of the index or middle finger with the concave side upward and then using that finger to place the lens on the eye. Rigid lenses should be placed directly on the cornea. Soft lenses may be placed on the sclera (white of the eye) and then slid into place. Another ...
Prime lenses have large apertures, compared with zoom lenses. These 85 mm lenses have maximum apertures of f /1.8 (left) and f /1.2 (right). In film and photography, a prime lens is a fixed focal length photographic lens (as opposed to a zoom lens), typically with a maximum aperture from f2.8 to f1.2. The term can also mean the primary lens in ...
This is any lens with a focal length longer than the diagonal measure of the film or sensor. [121] The most common type of long focus lens is the telephoto lens, a design that uses a special telephoto group to be physically shorter than its focal length. [122] Modern zoom lenses may have some or all of these attributes.
A telecentric lens is a special optical lens (often an objective lens or a camera lens) that has its entrance or exit pupil, or both, at infinity. The size of images produced by a telecentric lens is insensitive to either the distance between an object being imaged and the lens, or the distance between the image plane and the lens, or both, and ...
A zoom lens is a system of camera lens elements for which the focal length (and thus angle of view) can be varied, as opposed to a fixed-focal-length (FFL) lens . A true zoom lens or optical zoom lens is a type of parfocal lens, one that maintains focus when its focal length changes. [1]