Search

CN-118671932-B - Optical lens

CN118671932BCN 118671932 BCN118671932 BCN 118671932BCN-118671932-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 negative focal power, a fifth lens with positive focal power, a sixth lens with positive focal power, a seventh lens with negative focal power, and a seventh lens with negative focal power, wherein the object side surface of the first lens is concave, the object side surface of the second lens is convex, the image side surface of the second lens is convex, the third lens with positive focal power, the fourth lens with negative focal power, the fifth lens with positive focal power, the object side surface of the fifth lens with positive focal power are convex, the sixth lens with positive focal power, the image side surface of the sixth lens with positive focal power is convex, and the object side surface of the seventh lens with negative focal power is concave, and the object side surface of the second lens is concave, wherein the object side surface of the second lens and the object side surface of the second lens are provided with the radius of curvature R3 and the radius of curvature R4 of the object side surface of the second lens is satisfied with-1 < (R3-R4)/(R3+R 4) <0. 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, the image side surface of which is concave; the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; A third lens having positive optical power; a fourth lens having negative optical power; a fifth lens with positive focal power, the object side surface of which is a convex surface; a sixth lens element with positive refractive power having a convex image-side surface; a seventh lens with negative focal power, the object side surface of which is a concave surface; Wherein the object-side curvature radius R3 of the second lens and the image-side curvature radius R4 of the second lens satisfy-1 < (R3-R4)/(R3 + R4) <0; the total optical length TTL and the effective focal length f of the optical lens meet 15< TTL/f <30; The maximum field angle FOV of the optical lens and the aperture value FNo of the optical lens meet 70 DEG < FOV/FNo <100 DEG; The real image height IH corresponding to the maximum field angle of the optical lens and the real image height IHm corresponding to half of the value of the maximum field angle satisfy that 0.42 is less than or equal to IHm/IH is less than 0.5.
  2. 2. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f5 of the fifth lens satisfy 2< f5/f <15, and an effective focal length f of the optical lens and a focal length f6 of the sixth lens satisfy 2< f6/f <8.
  3. 3. 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.
  4. 4. 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 3.51 is equal to or greater than IH/f >3.
  5. 5. 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 2.07 is greater than or equal to BFL/f >1.5.
  6. 6. The optical lens system according to claim 1, wherein a distance Σct13 between the object side surface of the first lens element and the image side surface of the third lens element on the optical axis and an optical total length TTL of the optical lens system satisfy 0.5< Σct13/TTL <0.8.
  7. 7. 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-4.64≤f1/f < -2.
  8. 8. 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.
  9. 9. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f4 of the fourth lens satisfy-137.75≤f4/f < -15.
  10. 10. The optical lens as claimed in claim 1, wherein an effective focal length f of the optical lens and an image side curvature radius R2 of the first lens satisfy 3.06. Gtoreq.R 2/f >2.

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, the image side surface of which is concave; the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; A third lens having positive optical power; a fourth lens having negative optical power; a fifth lens with positive focal power, the object side surface of which is a convex surface; a sixth lens element with positive refractive power having a convex image-side surface; a seventh lens with negative focal power, the object side surface of which is a concave surface; wherein the object-side curvature radius R3 of the second lens and the image-side curvature radius R4 of the second lens satisfy-1 < (R3-R4)/(R3 + R4) <0. Further preferably, the optical total length TTL and the effective focal length f of the optical lens meet 15< TTL/f <30. Further preferably, the maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy 70 ° < FOV/Fno <100 °. 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 real image height IH corresponding to the maximum field angle and the real image height IHm corresponding to the center field angle of the optical lens satisfy IHm/IH <0.5. Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy f1/f < -2. 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 image side curvature radius R2 of the first lens satisfy R2/f >2. 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 of an optical lens in embodiment 3 of the present invention. Fig. 12 is a graph showing the field curvature of an o