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CN-120610376-B - Optical lens

CN120610376BCN 120610376 BCN120610376 BCN 120610376BCN-120610376-B

Abstract

The invention provides an optical lens which comprises seven lenses in total, a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with positive focal power, a convex object side and a concave image side, wherein the first lens with negative focal power, the object side and the image side are arranged from an object side to an imaging plane along an optical axis in sequence. The optical lens provided by the invention improves the imaging quality of the optical lens through specific surface shape collocation and reasonable focal power distribution, so that the lens has one or more advantages of large field angle, large aperture, large image height, high pixel, small distortion, high imaging quality and the like.

Inventors

  • HE XIAOYUAN
  • GAO BO
  • LI WEINA
  • JIANG JINGHONG
  • HUANG JIANXIN
  • LIANG ZIHAO

Assignees

  • 中山联拓光学有限公司

Dates

Publication Date
20260505
Application Date
20250624

Claims (10)

  1. 1. An optical lens comprising seven lenses in total, in order from an object side to an imaging surface along an optical axis, comprising: the first lens with negative focal power has a convex object side surface and a concave image side surface; a second lens with negative focal power, the object side of which is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; A fourth lens with positive focal power, the object side surface of which is a convex surface; A fifth lens having positive optical power, an image side surface of which is convex; A sixth lens element with negative refractive power having a concave object-side surface and a concave image-side surface; a seventh lens element with positive refractive power having a convex object-side surface and a concave image-side surface; The real image height IH corresponding to the maximum field angle of the optical lens and the total optical length TTL of the optical lens is 1.3< TTL/IH <1.6; the object-side curvature radius R11 of the sixth lens and the image-side curvature radius R12 of the sixth lens satisfy-0.72 < R11/R12< -0.62.
  2. 2. The optical lens according to claim 1, wherein an effective focal length f of the optical lens, a maximum field angle FOV of the optical lens, and a real image height IH corresponding to the maximum field angle of the optical lens satisfy 50 ° < (f x FOV)/IH <60 °.
  3. 3. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy-1.7 < f1/f < -1.6.
  4. 4. The optical lens of claim 1, wherein the object-side radius of curvature R13 of the seventh lens and the image-side radius of curvature R14 of the seventh lens satisfy-22 < (R13+R14)/(R13-R14) <76.
  5. 5. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f7 of the seventh lens satisfy 11< f7/f <35.
  6. 6. The optical lens of claim 1, wherein the object-side radius of curvature R1 of the first lens and the image-side radius of curvature R2 of the first lens satisfy 4< R1/R2<5.
  7. 7. The optical lens as claimed in claim 1, wherein a distance CT56 between the fifth lens and the sixth lens on the optical axis and a center thickness CT5 of the fifth lens satisfy 0.08< CT56/CT5<0.1.
  8. 8. The optical lens of claim 1, wherein the object-side light-passing half-caliber sagittal height SAG71 of the seventh lens, the image-side light-passing half-caliber sagittal height SAG72 of the seventh lens and the center thickness CT7 of the seventh lens satisfy-0.5 < (SAG 72-SAG 71)/CT 7< -0.15.
  9. 9. The optical lens of claim 1, wherein the object-side light-transmitting half-diameter DM11 of the first lens and the image-side light-transmitting half-diameter DM72 of the seventh lens satisfy 1.2< DM11/DM72<1.4.
  10. 10. The optical lens of claim 1, wherein a real image height IH corresponding to a maximum field angle of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy 6.5< IH/EPD <8.5.

Description

Optical lens Technical Field The invention relates to the technical field of imaging lenses, in particular to an optical lens. Background With the popularization of tele-office and online education, video conferences become an integral part of people's daily life and work, and the quality of video conferences depends largely on the optical lens of video conferences, which puts higher demands on video conference lenses. Video conference shots are often required to provide high resolution, such as 1080p or 4K, for example, to provide clear video quality, and are often required to be able to capture a larger range of shots, such as for efficient capturing of participants in a conference room. The conventional video conference lens has some limitations, such as low resolution, small shooting range, poor imaging effect in low light or dim environment, etc., so that it is highly desirable to provide an optical lens capable of meeting the use requirement of the video conference. Disclosure of Invention In view of the foregoing, an object of the present invention is to provide an optical lens having an advantage of excellent imaging quality. The invention provides an optical lens, seven lenses altogether, including in order from the object side to the imaging plane along the optical axis: the first lens with negative focal power has a convex object side surface and a concave image side surface; a second lens with negative focal power, the object side of which is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; A fourth lens with positive focal power, the object side surface of which is a convex surface; A fifth lens having positive optical power, an image side surface of which is convex; A sixth lens element with negative refractive power having a concave object-side surface and a concave image-side surface; a seventh lens element with positive refractive power having a convex object-side surface and a concave image-side surface; the real image height IH corresponding to the maximum field angle of the optical lens and the total optical length TTL of the optical lens is 1.3< TTL/IH <1.6. Further preferably, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens, and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 50 ° < (f×fov)/IH <60 °. Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy-1.7 < f1/f < -1.6. Further preferably, the object-side radius of curvature R13 of the seventh lens and the image-side radius of curvature R14 of the seventh lens satisfy-22 < (R13+R14)/(R13-R14) <76. Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy 11< f7/f <35. Further preferably, the object-side radius of curvature R1 of the first lens and the image-side radius of curvature R2 of the first lens satisfy 4< R1/R2<5. Further preferably, the distance CT56 between the fifth lens and the sixth lens on the optical axis and the center thickness CT5 of the fifth lens satisfy 0.08< CT56/CT5<0.1. Further preferably, the object-side light-transmitting half-caliber sagittal height SAG71 of the seventh lens, the image-side light-transmitting half-caliber sagittal height SAG72 of the seventh lens and the center thickness CT7 of the seventh lens satisfy-0.5 < (SAG 72-SAG 71)/CT 7< -0.15. Further preferably, the object side light-transmitting half aperture DM11 of the first lens and the image side light-transmitting half aperture DM72 of the seventh lens satisfy 1.2< DM11/DM72<1.4. Further preferably, the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens meet 6.5< IH/EPD <8.5. Compared with the prior art, the optical lens provided by the invention adopts seven lenses with specific focal power, and can improve the imaging quality of the optical lens, reduce the aberration and improve the imaging quality of the optical lens through specific surface shape collocation and reasonable focal power distribution, so that the lens has one or more advantages of large field angle, large aperture, large image height, high pixel, small distortion, high imaging quality and the like. Drawings The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which: Fig. 1 is a schematic structural diagram of an optical lens in embodiment 1 of the present invention. Fig. 2 is a graph showing a field curvature of an optical lens in embodiment 1 of the present invention. Fig. 3 is an F-Theta distortion graph of the optical lens in example 1 of the present invention. Fig. 4 is an axial aberration diagram o