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CN-118671931-B - Optical lens

CN118671931BCN 118671931 BCN118671931 BCN 118671931BCN-118671931-B

Abstract

The invention provides an optical lens which comprises seven 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 and the image side are both concave surfaces, the second lens is provided with negative focal power, the object side is provided with a concave surface, the third lens is provided with positive focal power, the image side is provided with a convex surface, the fourth lens is provided with negative focal power, the object side and the image side are both concave surfaces, the fifth lens is provided with positive focal power, the image side is provided with a convex surface, the sixth lens is provided with positive focal power, the object side and the image side are both convex surfaces, the seventh lens is provided with negative focal power, the object side curvature radius R1 of the first lens and the image side curvature radius R2 of the first lens meet the conditions of 0.5< (R1-R2)/(R1 + R2) <1.5. The optical lens has a large field angle and high resolution through reasonable configuration of the lens surfaces and reasonable collocation of optical power, has good imaging quality and clear edge field imaging.

Inventors

  • LONG LEI
  • CHEN WEIJIAN
  • WANG KEMIN

Assignees

  • 江西联创电子有限公司

Dates

Publication Date
20260512
Application Date
20240628

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: A first lens having negative optical power, both the object-side surface and the image-side surface of which are concave surfaces; a second lens with negative focal power, the object side of which is a concave surface; a third lens having positive optical power, the image side surface of which is convex; A fourth lens element having negative optical power, both the object-side and image-side surfaces thereof being concave; A fifth lens having positive optical power, an image side surface of which is convex; A sixth lens element with positive refractive power having convex object-side and image-side surfaces; a seventh lens with negative focal power, the object side surface of which is a concave surface; Wherein the object-side surface curvature radius R1 of the first lens and the image-side surface curvature radius R2 of the first lens meet the requirement that 1.03 is more than or equal to (R1-R2)/(R1+R2) >1; The maximum field angle FOV of the optical lens and the aperture value FNo of the optical lens meet 70 DEG < FOV/FNo <95 DEG; The effective focal length f of the optical lens, the real image height IH corresponding to the maximum field angle and the radian theta of the maximum half field angle meet the requirement that 1.31 is more than or equal to (IH/2)/(f multiplied by theta) >1.2.
  2. 2. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy-5 < f7/f < -1.
  3. 3. The optical lens according to claim 1, wherein the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy that 3.89 is equal to or greater than IH/f >3.
  4. 4. The optical lens according to claim 1, wherein the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy that 2.47 is equal to or greater than BFL/f >1.5.
  5. 5. 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-6.64≤f1/f < -3.
  6. 6. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy-10.10≤f2/f < -3.
  7. 7. The optical lens as claimed in claim 1, wherein the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy-23.29≤f4/f < -15.
  8. 8. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the object-side radius of curvature R3 of the second lens satisfy-39.15 < R3/f < -5.
  9. 9. The optical lens as claimed in claim 1, wherein the effective focal length f of the optical lens and the image side radius of curvature R8 of the fourth lens satisfy 49.18. Gtoreq.R 8/f >10.
  10. 10. The optical lens of claim 1, wherein the image-side radius of curvature R6 of the third lens and the object-side radius of curvature R7 of the fourth lens satisfy-1 < (R6-R7)/(R6 + R7) <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. The side view lens of the existing ADAS system is required to be provided with a plurality of lenses on two sides of a vehicle body to realize view angle fusion, and the problem that imaging quality is poor and obstacles cannot be clearly distinguished exists at the edge of a view field. Disclosure of Invention The invention aims to provide an optical lens with the advantage of good edge view field imaging effect. In order to achieve the above purpose, the invention adopts the following technical scheme: an optical lens comprising seven lenses in order from an object side to an imaging surface along an optical axis: A first lens having negative optical power, both the object-side surface and the image-side surface of which are concave surfaces; a second lens with negative focal power, the object side of which is a concave surface; a third lens having positive optical power, the image side surface of which is convex; A fourth lens element having negative optical power, both the object-side and image-side surfaces thereof being concave; A fifth lens having positive optical power, an image side surface of which is convex; A sixth lens element with positive refractive power having convex object-side and image-side surfaces; a seventh lens with negative focal power, the object side surface of which is a concave surface; Wherein, the object side curvature radius R1 of the first lens and the image side curvature radius R2 of the first lens satisfy (R1-R2)/(R1+R2) >1. Further preferably, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy 70 ° < FOV/Fno <95 °. Further preferably, the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens meet IH/f >3. Further preferably, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy BFL/f >1.5. Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy f1/f < -3. Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy f2/f < -3. Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy f4/f < -15. Further preferably, the effective focal length f of the optical lens and the object side curvature radius R3 of the second lens meet R3/f < -5 >. Further preferably, the effective focal length f of the optical lens and the image side curvature radius R8 of the fourth lens satisfy R8/f >10. Further preferably, the image side radius of curvature R6 of the third lens and the object side radius of curvature R7 of the fourth lens satisfy-1 < (R6-R7)/(R6+R7) <0. The optical lens provided by the invention has a large field angle and high resolution through reasonable configuration of the surface types of the lenses and reasonable collocation of the optical power, and has good imaging quality and clear edge field imaging. 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 curve of the optical lens in embodiment 1 of the present invention. Fig. 4 is a graph showing the relative illuminance of the optical lens in embodiment 1 of the present invention. Fig. 5 is an MTF graph of the optical lens in example 1 of the present invention. Fig. 6 is a schematic structural diagram of an optical lens in embodiment 2 of the present invention. Fig. 7 is a graph showing a field curvature of an optical lens in embodiment 2 of the present invention. Fig. 8 is an F-theta distortion curve of the optical lens in embodiment 2 of the present invention. Fig. 9 is a graph showing the relative illuminance of the optical lens in embodiment 2 of the present invention. Fig. 10 is an MTF graph of the optical lens in example 2 of the present invention. Fig. 11 is a schematic structural diagram