Short Throw Projection Lenses for Projectors

Abstract

The invention discloses a short focus projection lens for a projector. The short focus projection lens is composed of an optical lens assembly, a prism and a chip; the optical lens assembly comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens, wherein the prism is located between the eighth lens and the chip, the sixth lens and the seventh lens are double bonding lenses, the double bonding lenses are located between the fifth lens and the eighth lens; the seventh lens is located at one side of eighth lens, the fourth lens is located between the third lens and the fifth lens, and the first lens and the second lens are double bonding lenses located in front of the third lens; the second lens is located at one side of the third lens, a projection lens comprises fourteen surfaces, a third surface is an elliptic aspheric surface and a fourteen surface is an even harmonic aspheric surface. According to the short focus projection lens provided by the invention, the quantity of the lenses can be reduced by the elliptic aspheric surface and the even harmonic aspheric surface, the size of the maximum aperture can be shortened and the optical overall length can be reduced.

Description

technical field [0001] The invention relates to a short-focus projection lens, in particular to a short-focus projection lens for a projector. Background technique [0002] Projectors are widely used in life, business, education and military fields, making people have higher and higher requirements for the efficiency and portability of projectors, so the requirements for projection lenses are getting higher and higher, and short-focus projection lenses can To project a large picture, such as 1m to 1.5m, to project a picture of 80 to 120 inches, the existing short-focus projection lens generally has nine or more lenses, so that the existing short-focus projection lens has the largest aperture size Large size, long optical length, heavy weight and small field of view. Contents of the invention [0003] The object of the present invention is to provide a short-focus projection lens for a projector in order to solve the above problems. [0004] In order to achieve the above ...

AI Technical Summary

Problems solved by technology

[0002] Projectors are widely used in life, business, education and military fields, making people have higher and higher requirements for the efficiency and portability of projectors, so the requirements for projection lenses are getting higher and higher, and short-focus projection lenses can To project a large picture, such as 1m to 1.5m, to project a picture of 80 to 120 inches, the existing short-focus projection lens generally has nine or more lenses, so that the existing short-focus projection lens has the largest aperture size Large size, long optical length, heavy weight and small field of view

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