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CN-118707689-B - Optical lens

CN118707689BCN 118707689 BCN118707689 BCN 118707689BCN-118707689-B

Abstract

The invention provides an optical lens which comprises six 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 and the image side surface of the first lens are concave, the second lens is provided with positive focal power, the third lens is provided with positive focal power, the fourth lens is provided with negative focal power, the object side surface of the fourth lens is concave, the image side surface of the fourth lens is convex, the fifth lens is provided with positive focal power, the sixth lens is provided with negative focal power, the object side surface of the sixth lens is concave, and the image side surface of the sixth lens is convex. The optical lens provided by the invention has one or more advantages of low cost, high resolution, high imaging quality and the like through specific surface shape collocation and reasonable focal power distribution.

Inventors

  • Xiao Pulu
  • WEI WENZHE
  • 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 six lenses 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 having positive optical power; A third lens having positive optical power; a fourth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; a fifth lens having positive optical power; a sixth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; Wherein the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy 0.6< f3/f <2.6; 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 the conditions that IH/EPD is 1.7< 2.5; The curvature radius R7 of the fourth lens object side surface and the curvature radius R8 of the fourth lens image side surface meet the condition that (R7-R8)/(R7 + R8) < -0.1 is minus 0.9 <.
  2. 2. The optical lens according to claim 1, wherein a focal length f4 of the fourth lens and an effective focal length f of the optical lens satisfy-2.7 < f4/f < -0.9.
  3. 3. The optical lens of claim 1, wherein the radius of curvature R11 of the object-side surface of the sixth lens element and the effective focal length f of the optical lens element satisfy-1.3 < R11/f < -0.2, and the radius of curvature R12 of the image-side surface of the sixth lens element and the effective focal length f of the optical lens element satisfy-8.4 < R12/f < -1.2.
  4. 4. The optical lens of claim 1, wherein the radius of curvature R7 of the fourth lens element object-side surface and the radius of curvature R8 of the fourth lens element image-side surface satisfy 0.1< R7/R8<0.5.
  5. 5. The optical lens of claim 1, wherein a radius of curvature R7 of the object-side surface of the fourth lens element and a focal length f4 of the fourth lens element satisfy 0.3< R7/f4<0.9, and a radius of curvature R8 of the image-side surface of the fourth lens element and a focal length f4 of the fourth lens element satisfy 1.5< R8/f4<3.3.
  6. 6. The optical lens of claim 1, wherein the radius of curvature R7 of the fourth lens element object-side surface and the radius of curvature R8 of the fourth lens element image-side surface satisfy-0.7 < (R7-R8)/(R7 + R8) < -0.4.
  7. 7. The optical lens according to claim 1, wherein the real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the radian θ of the maximum half field angle of the optical lens satisfy 0.85< (IH/2)/(f x θ) <1.00.
  8. 8. The optical lens according to claim 1, wherein a focal length f3 of the third lens and an effective focal length f of the optical lens satisfy 0.7< f3/f <2.4; 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 the requirement that IH/EPD is 1.9< 2.4.
  9. 9. The optical lens of claim 1, wherein the light-transmitting half-aperture d7 of the object side of the fourth lens and the light-transmitting half-aperture sagittal height Sag7 of the object side of the fourth lens satisfy-0.4 < Sag7/d7<0, and the light-transmitting half-aperture d8 of the image side of the fourth lens and the light-transmitting half-aperture sagittal height Sag8 of the image side of the fourth lens satisfy-0.2 < Sag8/d8<0.
  10. 10. The optical lens of claim 1, wherein the total optical length TTL of the optical lens and the sum of center thicknesses of the first, second, third, fourth, fifth and sixth lenses ΣCT satisfy 2.0< TTL/ΣCT <3.1.

Description

Optical lens Technical Field The invention relates to the technical field of imaging lenses, in particular to an optical lens. Background In modern automotive technology, vehicle cameras play a vital role. They include multiple types of cameras, such as inward looking, rearward looking, forward looking, side looking, and around looking cameras, each with its unique application scenario. For example, the rearview camera is mainly used for reversing images, and the looking-around camera provides 360-degree panoramic view, so that the perception capability of a driver is greatly enhanced. Among the vehicle-mounted cameras, a front-view camera is a core component of an ADAS (advanced driving assistance system), which is generally mounted on a front windshield, and is mainly responsible for forward collision early warning, lane departure warning, pedestrian detection, and the like. Currently, the price of a front-view camera is usually far higher than that of other types of cameras due to the complex algorithm and chip processing involved, which also reflects the importance of the front-view camera in a vehicle-mounted camera system. With the rapid development of advanced driving assistance systems, the requirements for the front view lens are also increasing. Therefore, it is necessary to develop an optical lens having a 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. The invention adopts the technical scheme that: An optical lens comprising six 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 having positive optical power; A third lens having positive optical power; a fourth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; a fifth lens having positive optical power; a sixth lens element with negative refractive power having a concave object-side surface and a convex image-side surface; Wherein the focal length f3 of the third lens and the effective focal length f of the optical lens meet 0.6< f3/f <2.6. Further preferably, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy-2.7 < f4/f < -0.9. Further preferably, the radius of curvature R11 of the object side surface of the sixth lens and the effective focal length f of the optical lens meet the condition that R11/f < -0.2 is 1.3, and the radius of curvature R12 of the image side surface of the sixth lens and the effective focal length f of the optical lens meet the condition that R12/f < -1.2 is 8.4. Further preferably, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy 0.1< R7/R8<0.5. Further preferably, the radius of curvature R7 of the object side surface of the fourth lens element and the focal length f4 of the fourth lens element satisfy 0.3< R7/f4<0.9, and the radius of curvature R8 of the image side surface of the fourth lens element and the focal length f4 of the fourth lens element satisfy 1.5< R8/f4<3.3. Further preferably, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy-0.9 < - (R7-R8)/(R7 + R8) < -0.1. Further preferably, the real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens and the radian theta of the maximum half field angle of the optical lens satisfy 0.85< (IH/2)/(f x theta) <1.00. 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 1.7< IH/EPD <2.5. Further preferably, the light transmission half-caliber d7 of the object side surface of the fourth lens and the light transmission half-caliber sagittal height Sag7 of the object side surface of the fourth lens meet the condition that the ratio of-0.4 < Sag7/d7<0, and the ratio of the light transmission half-caliber d8 of the image side surface of the fourth lens and the light transmission half-caliber sagittal height Sag8 of the image side surface of the fourth lens meet the condition that the ratio of-0.2 < Sag8/d8<0. Further preferably, the total optical length TTL of the optical lens and the sum ΣCT of the center thicknesses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens satisfy that 2.0< TTL/ΣCT <3.1. The optical lens provided by the invention adopts six lenses with specific focal power, and can improve the imaging quality of the optical lens, reduce the aberration, improve the imaging quality of the optical lens