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CN-119024526-B - Optical lens

CN119024526BCN 119024526 BCN119024526 BCN 119024526BCN-119024526-B

Abstract

The invention provides an optical lens which comprises eight lenses in sequence from an object side to an imaging surface along an optical axis, wherein the first lens is provided with negative focal power, the object side surface is a convex surface, the image side surface is a concave surface, the second lens is provided with positive focal power, the object side surface is a concave surface, the image side surface is a convex surface, the third lens is provided with negative focal power, the object side surface is a convex surface, the image side surface is a concave surface, the fourth lens is provided with positive focal power, the object side surface is a concave surface, the image side surface is a convex surface, the fifth lens is provided with positive focal power, the object side surface and the image side surface are convex surfaces, the sixth lens is provided with positive focal power, the object side surface and the image side surface are both convex surfaces, the seventh lens is provided with negative focal power, the object side surface and the image side surface are both concave surfaces, and the eighth lens is provided with positive focal power. The optical lens provided by the invention can improve the imaging quality of the optical lens, reduce the aberration and improve the imaging quality of the optical lens.

Inventors

  • WU HONGYU
  • CHEN WEIJIAN

Assignees

  • 江西联创电子有限公司

Dates

Publication Date
20260512
Application Date
20240930

Claims (10)

  1. 1. An optical lens comprising eight lenses in total, in order from an object side to an imaging plane along an optical axis: the first lens with negative focal power has a convex object side surface and a concave image side surface; a second lens element with positive refractive power having a concave object-side surface and a convex image-side surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a fifth lens element with positive refractive power having convex object-side and image-side surfaces; A sixth lens element with positive refractive power having convex object-side and image-side surfaces; A seventh lens with negative focal power, wherein the object side surface and the image side surface of the seventh lens are concave surfaces; an eighth lens element with positive refractive power having convex object-side and image-side surfaces; Wherein the object-side surface curvature radius R5 of the third lens and the object-side surface curvature radius R7 of the fourth lens satisfy-0.8 < (R5+R7)/(R5-R7) <0; The combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy-1.5 < f123/f45678< -0.7.
  2. 2. 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 2.1< IH/EPD <3.2.
  3. 3. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f2 of the second lens satisfy 13< f 2/f≤ 131.72, and an effective focal length f of the optical lens and a focal length f3 of the third lens satisfy-49.93≤f3/f < -10.
  4. 4. The optical lens of claim 1, wherein the object-side radius of curvature R5 of the third lens and the object-side radius of curvature R7 of the fourth lens satisfy-0.34 < (R5+R7)/(R5-R7) < -0.08; The combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy-1.24 < f123/f45678< -0.97.
  5. 5. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the object-side radius of curvature R5 of the third lens satisfy 8.1< R5/f <12.2, and the effective focal length f of the optical lens and the object-side radius of curvature R7 of the fourth lens satisfy-24 < R7/f < -9.9.
  6. 6. The optical lens of claim 1, wherein an object-side radius of curvature R5 of the third lens and an image-side radius of curvature R6 of the third lens satisfy 1.2< R5/R6<2.7, and wherein an object-side radius of curvature R5 of the third lens and an object-side radius of curvature R7 of the fourth lens satisfy-0.95 < R5/R7< -0.4.
  7. 7. The optical lens of claim 1, wherein an object-side radius of curvature R5 of the third lens and a focal length f3 of the third lens satisfy-1 < R5/f3< -0.1, and an object-side radius of curvature R7 of the fourth lens and a focal length f4 of the fourth lens satisfy-6.1 < R7/f4< -2.6.
  8. 8. The optical lens of claim 1, wherein the object-side radius of curvature R5 of the third lens and the image-side radius of curvature R6 of the third lens satisfy 0.1< (R5-R6)/(R5+R6) <0.5.
  9. 9. The optical lens of claim 1, wherein the object-side radius of curvature R7 of the fourth lens and the image-side radius of curvature R8 of the fourth lens satisfy 1.1< (R7+R8)/(R7-R8) <1.8.
  10. 10. The optical lens of claim 1, wherein the object-side light-transmitting half-aperture sagittal height Sag5 of the third lens and the object-side light-transmitting half-aperture d5 of the third lens satisfy 0< Sag5/d5<0.1, and the object-side light-transmitting half-aperture sagittal height Sag7 of the fourth lens and the object-side light-transmitting half-aperture d7 of the fourth lens satisfy-0.1 < Sag7/d7<0.

Description

Optical lens Technical Field The invention relates to the technical field of imaging lenses, in particular to an optical lens. Background Along with the continuous improvement of the requirements of people on driving experience, the vehicle-mounted application optical lens is increasingly used in intelligent driving, and the position of the vehicle-mounted optical lens in the related industries of automobiles is continuously improved. Advanced Driving Assistance Systems (ADASs) play an important role in intelligent driving, and collect environmental information through various lenses in combination with sensors to ensure driving safety of drivers. In addition to the light, thin, short, small, and high-pixel and high-resolution characteristics of the conventional ADAS system lens, the optical lens is required to be capable of clearly imaging under a low-illuminance condition, so that it is required to develop an optical lens with good imaging effect. 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. In order to achieve the above purpose, the invention adopts the following technical scheme: An optical lens comprising eight lenses in order from an object side to an imaging surface along an optical axis: the first lens with negative focal power has a convex object side surface and a concave image side surface; a second lens element with positive refractive power having a concave object-side surface and a convex image-side surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a fifth lens element with positive refractive power having convex object-side and image-side surfaces; A sixth lens element with positive refractive power having convex object-side and image-side surfaces; A seventh lens with negative focal power, wherein the object side surface and the image side surface of the seventh lens are concave surfaces; an eighth lens element with positive refractive power having convex object-side and image-side surfaces; the object-side surface curvature radius R5 of the third lens and the object-side surface curvature radius R7 of the fourth lens satisfy-0.8 < (R5+R7)/(R5-R7) <0. 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 that the ratio of IH/EPD is 2.1< 3.2. Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy f2/f >13, and the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy f3/f < -10. Further preferably, the combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45678 of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy-1.5 < f123/f45678< -0.7. Further preferably, the effective focal length f of the optical lens and the object side curvature radius R5 of the third lens meet 8.1< R5/f <12.2, and the effective focal length f of the optical lens and the object side curvature radius R7 of the fourth lens meet-24 < R7/f < -9.9. Further preferably, the object-side surface curvature radius R5 of the third lens and the image-side surface curvature radius R6 of the third lens satisfy 1.2< R5/R6<2.7, and the object-side surface curvature radius R5 of the third lens and the object-side surface curvature radius R7 of the fourth lens satisfy-0.95 < R5/R7< -0.4. Further preferably, the object-side radius of curvature R5 of the third lens and the focal length f3 of the third lens satisfy the condition that 1< R5/f3< -0.1, and the object-side radius of curvature R7 of the fourth lens and the focal length f4 of the fourth lens satisfy the condition that 6.1< R7/f4< -2.6. Further preferably, the object-side surface radius of curvature R5 of the third lens and the image-side surface radius of curvature R6 of the third lens satisfy 0.1< (R5-R6)/(R5+R6) <0.5. Further preferably, the object-side surface radius of curvature R7 of the fourth lens and the image-side surface radius of curvature R8 of the fourth lens satisfy 1.1< (R7+R8)/(R7-R8) <1.8. Further preferably, the object-side light-transmitting half-caliber sagittal height Sag5 of the third lens and the object-side light-transmitting half-caliber d5 of the third lens meet 0< Sag5/d5<0.1, and the object-side light-transmitting half-caliber sagittal height Sag7 of the fourth lens and the object-side light-transmitting half-caliber d7 of the fourth lens meet-0.1 < Sag7/d7<0. The optical lens provided by the invention adopts eight lenses with specific focal power, and can improve the imaging quality of the optical lens, reduce t