Medium-focus large-aperture long-flange video lens with focal length of 50mm

By designing a medium-focus large aperture long flange video lens with a focal length of 50mm, using a combination of standard glass spherical lenses and glass aspherical lenses, the focal length ratio and structure of the optical system are optimized, and the shortcomings of existing medium-focus video lenses in MTF resolution, distortion, light-through aperture, chromatic aberration and overall optical length are solved, and a high-performance and compact structure video lens is achieved.

CN119535742AActive Publication Date: 2025-02-28ZHUHAI CHUANFU OPTICAL TECH
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Patent Information

Application Number
CN202510105129.7
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-01-23
Publication Date
2025-02-28
Estimated Expiration
2045-01-23

AI Technical Summary

Technical Problem

The existing midfocus video lenses have shortcomings in MTF resolution, distortion, light-through aperture, chromatic aberration and optical total length, and cannot meet the market demand for midfocus video shooting with long flange rear focus, especially video lenses with a focal length of 50mm.

Method used

A medium-focus large aperture long flange video lens with a focal length of 50mm was designed, and the optimized combination of 13 standard glass spherical lenses and 1 glass aspherical lens was used. Through the combination of the first lens group and the second lens group, the focal length ratio of 0.47 < f2/f1 < 0.56 was met, and the total optical length and rear focal distance were optimized.

Benefits of technology

It realizes the advantages of large optical aperture, high MTF resolution, small distortion, reduced achromatic aberration and long flange rear focal. The total optical length is between 155mm and 162mm, meeting the camera module needs of longer flange rear focals.

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Abstract

The invention relates to a medium-focus large-aperture long-flange video lens with a focal length of 50mm. The medium-focus large-aperture long-flange video lens comprises a first lens group, an iris diaphragm and a second lens group which are sequentially arranged along a light incidence direction of a light path, wherein the first lens group serves as an immovable fixed group, the focal power is positive, and the first lens group is composed of lenses L11-L17 which are sequentially arranged in the light incidence direction of a light path and comprises two groups of doublet lenses and a group of triplet lenses; the second lens group serves as a movable focusing group, the focal power is positive, and the second lens group is composed of lenses L21-L27 which are sequentially arranged in the light incidence direction of the light path and comprises two groups of doublet lenses and a glass aspheric lens; the focal length value f1 of the first lens group and the focal length value f2 of the second lens group satisfy 0.47 lt; f2 / f1lt; and 0.56% of the total weight. The lens achieves a large clear aperture, high MTF resolution, small distortion and reduced achromatism, is short in total optical length, and meets a camera module matched with a long flange back focus.
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Citation Information

Patent Citations

  • Aspheric wide-angle long flange video lens

    CN115185072A

Cited By

  • Medium-focus large-aperture long-flange video lens with focal length of 35mm

    CN119805716A

  • A medium focal length, large aperture, long flange video lens with a focal length of 35mm

    CN119805716B