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EP-4471480-B1 - OPTICAL LENS

EP4471480B1EP 4471480 B1EP4471480 B1EP 4471480B1EP-4471480-B1

Inventors

  • CHEN, WEIJIAN
  • XU, Yuxuan

Dates

Publication Date
20260506
Application Date
20230117

Claims (8)

  1. An optical lens, comprising a total of six lenses (L1, L2, L3, L4, L5, L6), wherein from an object side to an imaging plane (S17) along an optical axis of the optical lens, the optical lens sequentially comprises: a first lens (L1) with a negative focal power, an object side surface (S1) of the first lens (L1) being convex, and an image side surface (S2) of the first lens (L1) being concave; a second lens (L2) with a positive focal power, an object side surface (S3) of the second lens (L2) being concave, and an image side surface (S4) of the second lens (L2) being convex; a stop (ST); a third lens (L3) with a positive focal power, both an object side surface (S5) and an image side surface (S6) of the third lens (L3) being convex; a fourth lens (L4) with a positive focal power, both an object side surface (S7) and an image side surface (S8) of the fourth lens (L4) being convex; a fifth lens (L5) with a negative focal power, both an object side surface (S9) and an image side surface (S10) of the fifth lens (L5) being concave; and a sixth lens (L6) with a positive focal power, an object side surface (S11) of the sixth lens (L6) being convex, and an image side surface (S12) of the sixth lens (L6) being concave; wherein the fourth lens (L4) and the fifth lens (L5) are cemented to form a cemented lens; an effective focal length f of the optical lens and a true image height IH corresponding to a maximum field of view meets an expression: 0.6< f /IH<0.7; an effective aperture HD1 of the object side surface (S1) of the first lens (L1) corresponding to a half field of view of the optical lens and an effective aperture D1 of the object side surface (S1) of the first lens (L1) meet an expression: 0.55<HD1/D1<0.65; the effective focal length f of the optical lens and a focal length f 1 of the first lens (L1) meet an expression: -1.55< f 1/ f <-1.35; a radius of curvature R1 of the object side surface (S1) of the first lens (L1), a radius of curvature R2 of the image side surface (S2) of the first lens (L1), and a center thickness CT1 of the first lens (L1) meet an expression: 1.5< R1/(R2+CT1) <1.9; and the effective focal length f of the optical lens and a focal length f 3 of the third lens (L3) meet an expression: 1.5< f 3/ f <2.5; the effective focal length f of the optical lens and a focal length f 2 of the second lens (L2) meet an expression: 3.5< f 2/ f <9.0; a radius of curvature R3 of the object side surface (S3) and a radius of curvature R4 of the image side surface (S4) of the second lens (L2) meet an expression: 0.90<R3/R4<1.95; and a center thickness CT2 of the second lens (L2) and a total track length TTL of the optical lens meet an expression: 0.19≤CT2/TTL≤0.22.
  2. The optical lens of claim 1, wherein the effective focal length f of the optical lens meets an expression: 5.0mm< f <5.5mm.
  3. The optical lens of any one of claims 1 to 2, wherein an f-number of the optical lens meets an expression: 1.4<FNO≤1.6.
  4. The optical lens of any one of claims 1 to 3, wherein a chief ray angle CRA on the imaging plane (S17) at a full field of view of the optical lens meets an expression: 1°<CRA<10°.
  5. The optical lens of any one of claims 1 to 4, wherein a radius of curvature R5 of the object side surface (S5) of the third lens (L3) and the focal length f 3 of the third lens (L3) meet an expression: 0.85<R5/ f 3<1.15; and a center thickness CT3 of the third lens (L3) and the total track length TTL of the optical lens meet an expression: 0.16≤CT3/TTL≤0.24.
  6. The optical lens of any one of claims 1 to 5, wherein the effective focal length f of the optical lens and a focal length f4 of the fourth lens (L4) meet an expression: 1.5< f 4/ f <2.5.
  7. The optical lens of any one of claims 1 to 6, wherein the effective focal length f of the optical lens and a focal length f 5 of the fifth lens (L5) meet an expression: -1.6< f 5/ f <-1.0; and a radius of curvature R7 of the object side surface (S7) of fourth lens (L4) and a radius of curvature R10 of the image side surface (S10) of the fifth lens (L5) meet an expression: 0.90<R7/R10<1.65.
  8. The optical lens of any one of claims 1 to 7, wherein the effective focal length f of the optical lens and a focal length f 6 of the sixth lens (L6) meet an expression: 2.0< f 6/ f <3.5; and a radius of curvature R11 of the object side surface (S11) and a radius of curvature R12 of the image side surface (S12) of the sixth lens (L6) meet an expression: -1.9< (R11+R12)/(R11-R12) <-1.1.

Description

TECHNICAL FIELD The present disclosure relates to the technical field of imaging lens, and in particular to an optical lens. BACKGROUND In recent years, with the rapid development of the automatic driving assistance systems, image algorithms are upgrading. An automotive lens is a key component of the automatic driving assistance system to obtain external information, and it also needs to be upgraded to meet the requirements of the present stage. At present, for obtaining information in a single direction, the conventional automatic driving assistance system generally depends on a long-focus lens and a wide-angle lens. Although the long-focus lens has a long focal length, it has a small field of view, and it is generally used to capture objects at a longdistance for observation. Although the wide-angle lens has a large field of view, it has a short focal length, and it is generally used to capture objects at a short-distance for observation. Therefore, there is a need to design an optical lens which integrates functions of the long-focus lens and the wide-angle lens, and has a large aperture, a large field of view and a high resolution, so as to replace multiple lenses each having a single function in the traditional automatic driving assistance system. US11125971B2 discloses a vehicle lens. From an object side to an image side, the vehicle lens sequentially includes a first group with a negative refractive power, a stop, a second group with a positive refractive power, and a third group with a positive refractive power. The first group includes a first lens and a second lens. The second group includes at least a third lens. The third group includes a fourth lens, a fifth lens, and a sixth lens, wherein the fourth lens has a positive refractive power, a convex object side surface and a convex image side surface, the fifth lens has a negative refractive power and a concave object side surface, the sixth lens has a positive refractive power. The third group includes at least one aspheric lens. SUMMARY Embodiments of the present disclosure provide an optical lens with a large aperture, a large field of view and a high resolution. The invention is set out in the appended set of claims. Different from the related art, the embodiments of the present disclosure have beneficial effects as follows: a large aperture, a large field of view and a high resolution are enabled by reasonably matching the lens shapes among the lenses and combining the refractive power of various lenses. A part of additional aspects and advantages of the present disclosure are set forth in the following description, and a part thereof would become apparent from the following description, or be understood by practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and/or additional aspects and advantages of the present disclosure will become apparent and well understood from the following description of the embodiments in conjunction with the drawings, in which: FIG. 1 is a schematic view illustrating a structure of an optical lens according to Embodiment 1 of the present disclosure.FIG. 2 is a graph of field curvatures of the optical lens according to Embodiment 1 of the present disclosure.FIG. 3 is a graph of axial aberrations of the optical lens according to Embodiment 1 of the present disclosure.FIG. 4 is a graph of lateral chromatic aberrations of the optical lens according to Embodiment 1 of the present disclosure.FIG. 5 is a graph of Modulation Transfer Function (MTF) of the optical lens according to Embodiment 1 of the present disclosure.FIG. 6 is a schematic view illustrating a structure of an optical lens according to Embodiment 2 of the present disclosure.FIG. 7 is a graph of field curvatures of the optical lens according to Embodiment 2 of the present disclosure.FIG. 8 is a graph of axial aberrations of the optical lens according to Embodiment 2 of the present disclosure.FIG. 9 is a graph of lateral chromatic aberrations of the optical lens according to Embodiment 2 of the present disclosure.FIG. 10 is a graph of MTF of the optical lens according to Embodiment 2 of the present disclosure.FIG. 11 is a schematic view illustrating a structure of an optical lens according to Embodiment 3 of the present disclosure.FIG. 12 is a graph of field curvatures of the optical lens according to Embodiment 3 of the present disclosure.FIG. 13 is a graph of axial aberrations of the optical lens according to Embodiment 3 of the present disclosure.FIG. 14 is a graph of lateral chromatic aberrations of the optical lens according to Embodiment 3 of the present disclosure.FIG. 15 is a graph of MTF of the optical lens according to Embodiment 3 of the present disclosure.FIG. 16 is a schematic view illustrating a structure of an optical lens according to Embodiment 4 of the present disclosure.FIG. 17 is a graph of field curvatures of the optical lens according to Embodiment 4 of the present disclosure.FIG. 18 is a graph of a