Lenses are classified into two types according to the shape and purpose of the lens, Concave lens and Convex lens, The convex lens is thick at the center and has less thickness at the tips, It collects the light rays falling on it, So, it is called the converging lens. Lenticular lenses are a group of microlenses that are used in lenticular printing, They produce images that have an illusion of depth. Fresnel lens is a lens whose optical surface is divided into narrow rings, This allows the lens to be much thinner and lighter than conventional lenses.
The aspheric lens is known as a non-spherical lens, Aspheric lens is the lens whose surface is not part of a sphere or a cylinder, The complex surface of the aspheric lens reduces or eliminates optical aberrations as compared to a simple lens, the single aspheric lens can replace the combination of simple lenses resulting in a system with a much-reduced size.Ĭylindrical Lenses have a curvature along only one axis, they convert laser diode elliptical light into a round beam or focus light into a line, such as motion picture anamorphic lenses. The simple lens is a single piece of magnifying material while the compound lens consists of a number of simple lenses arranged along a common axis, Optical aberrations are found in simple lenses while this property is eliminated in the compound lens, The magnification of compound lens can be adjusted as per the user’s requirements. Lenses are categorized as simple lenses or compound lenses. Lenses are basically magnifying glasses with curved sides. When the lens is biconcave or plano-concave, the collimated beam of light passing through the lens diverges (spread) the lens is called the negative or diverging lens, The beam, after passing through the lens, appears to emanate from a particular point on the axis in front of the lens, For a thin lens in air, the distance from this point to the lens is the focal length, though it is negative with respect to the focal length of a converging lens.Ĭonvex-concave (meniscus) lenses can be either positive or negative, depending on the relative curvatures of the two surfaces, The negative meniscus lens has a steeper concave surface and is thinner at the centre than at the periphery, Conversely, the positive meniscus lens has a steeper convex surface and is thicker at the centre than at the periphery. When one of the surfaces is flat, the lens is plano-convex or plano-concave depending on the curvature of the other surface, The lens with one convex and one concave side is convex-concave or meniscus, this type of lens is most commonly used in corrective lenses. Lenses are classified by the curvature of the two optical surfaces, The lens is biconvex (or double convex, or just convex) if both surfaces are convex, When both surfaces have the same radius of curvature, the lens is equiconvex, The lens with two concave surfaces is biconcave (or just concave). The lenses are used in Microscopes which are used to form magnified images of tiny bodies that can not be seen with the naked eye and they are used in making medical glasses to treat vision defects such as myopia and hypermetropia. Lenses can be used in a magnifying glass, they can be used in prosthetics for the correction of visual impairments, They can attenuate light, They are used in imaging systems, and they can be used in radar systems. The lenses are used in designing some optical devices such as Telescopes which are used for the formation of enlarged images of heavenly bodies. The person who fixes the watches uses a magnifier lens to see the minute parts of the watches, The lensesare used in the manufacture of many things as projectors, cameras, and magnifying lenses. Convex lenses are used in projectors, Multi-junction Solar cells, and peepholes in doors. The lenses are used in many things, They are used in medical eyeglasses either for reading or walking, They are used in wars, and the leaders use binoculars to follow the battles. Types and uses of lenses in our life Importance of lenses
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