Zoom lens

Abstract

This invention discloses one micro variable focus lens head, which orderly comprises negative diopter first lens set, positive diopter second lens set, positive third lens set, positive fourth lens set and positive fifth lens set, wherein, when the variable focus lens head changes from remote distance; the fourth lens set moves from object side to picture side. This invention adopts negative, positive, positive, positive and positive sets of lens structure to form short and compact variable lens head system.

Description

【Technical field】 [0001] The invention relates to a zoom lens, in particular to a zoom projection lens with miniaturization, high resolution and long back focal length which can be applied in an optical projection system. 【Background technique】 [0002] As one of the core components of the imaging and projection system, the primary performance index of the optical lens is to meet the requirements of high zoom ratio and high resolution. Usually, a high zoom ratio lens is realized by multi-group lens groups, multiple lenses, and a longer lens length type, and special low dispersion lenses and aspheric lenses are added to meet the resolution requirements. Existing zoom lenses are generally designed for imaging purposes, so the back focal length (back focal length) is usually not long, but it can meet the requirements of imaging in general photography. However, for the optical projection system, the existing general zoom lenses often cannot be used in the optical projection sys...

AI Technical Summary

Problems solved by technology

However, increasing the diopter of each lens group will also cause aberration fluctuations to become larger with the zooming process and it is difficult to make good corrections

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