Optical lens

Abstract

The invention provides an optical lens, which comprises five lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with positive focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a convex surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens near the optical axis is a convex surface; and the fifth lens has negative focal power, the object side surface of the fifth lens is a convex surface near the optical axis, and the image side surface of the fifth lens is a concave surface near the optical axis. The optical lens provided by the invention can be suitable for an infrared light band, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages of large field angle, large image surface, high imaging quality and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] The OMS (Occupancy Monitoring System) optical lens is a core component of the intelligent cockpit perception layer, mainly responsible for core functions such as DMS (Driver Monitoring System), passenger identification, child left detection, and cockpit behavior analysis. With the continuous popularization of intelligent driving and the mandatory landing of global child left safety regulations, cockpit monitoring has been upgraded from "single driver monitoring" to "full cockpit multi-target perception", which puts higher requirements on the performance of OMS lenses. Currently, OMS lenses mainly have poor resolution, low resolution, and are prone to defocus in high and low temperature environments, and can only be applied in good light conditions, which cannot meet the use requirements in low light conditions at night. Therefore, developing an OMS optical lens that takes into account full cockpit coverage, high detail capture, and clear imaging in low light has become an urgent need for the industry. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens with excellent imaging quality.

[0004] The technical scheme adopted by the present application is:

[0005] An optical lens has five lenses with optical power, which includes, along the optical axis from the object side to the imaging surface:

[0006] A first lens with negative optical power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface;

[0007] A second lens with positive optical power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface;

[0008] A third lens with positive optical power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface;

[0009] A fourth lens with positive optical power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface near the optical axis;

[0010] A fifth lens with negative optical power, the object side surface of which is a convex surface near the optical axis, and the image side surface of which is a concave surface near the optical axis;

[0011] Wherein, the combined focal length f12 of the first lens and the second lens and the combined focal length f35 of the third lens to the fifth lens satisfy: 3.6 < f12 / f35 < 5; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.5 < TTL / f < 6.7.

[0012] Further preferably, the focal length f1 of the first lens and the combined focal length f12 of the first lens and the second lens satisfy: -0.25 < f1 / f12 < -0.18.

[0013] Further preferably, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 45° < f x FOV / IH < 55°.

[0014] Further preferably, the object-side surface curvature radius R1 of the first lens and the image-side surface curvature radius R2 of the first lens satisfy: 1 < (R1+R2) / (R1-R2) < 1.35.

[0015] Further preferably, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.8 < f1 / f < -1.5; the object-side surface curvature radius R1 of the first lens and the effective focal length f of the optical lens satisfy: 7 < R1 / f < 10.5; the image-side surface curvature radius R2 of the first lens and the effective focal length f of the optical lens satisfy: 0.7 < R2 / f < 0.85.

[0016] Further preferably, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.8 < f1 / f2 < -0.65; the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 0.27 < f2 / f3 < 0.34.

[0017] Further preferably, the image-side surface half catadioptric radius SAG42 of the fourth lens, the object-side surface half catadioptric radius SAG41 of the fourth lens and the central thickness CT4 of the fourth lens satisfy: -0.5 < (SAG42-SAG41) / CT4 < -0.35.

[0018] Further preferably, the object-side surface half catadioptric radius DM11 of the first lens and the image-side surface half catadioptric radius DM52 of the fifth lens satisfy: 1.2 < DM11 / DM52 < 1.6.

[0019] Further preferably, the object-side surface half catadioptric radius DM11 of the first lens and the focal length f1 of the first lens satisfy: 1.8 < DM11 / f1 < 2.3.

[0020] Further preferably, the Abbe number Vd4 of the fourth lens and the Abbe number Vd5 of the fifth lens satisfy: 29 < Vd4-Vd5 < 35.

[0021] The optical lens provided by the application has five lenses with optical power, can be applied to an infrared light wave band, can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and has one or more advantages such as a large field of view, a large image surface and high imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0023] Figure 1 It is a structural schematic diagram of the optical lens in the embodiment 1 of the present application.

[0024] Figure 2 It is a field curvature curve diagram of the optical lens in the embodiment 1 of the present application.

[0025] Figure 3 It is an F-Theta distortion curve diagram of the optical lens in the embodiment 1 of the present application.

[0026] Figure 4 It is an axial aberration curve diagram of the optical lens in the embodiment 1 of the present application.

[0027] Figure 5 It is a lateral chromatic aberration curve diagram of the optical lens in the embodiment 1 of the present application.

[0028] Figure 6 It is an MTF curve diagram of the optical lens in the embodiment 1 of the present application.

[0029] Figure 7 It is a structural schematic diagram of the optical lens in the embodiment 2 of the present application.

[0030] Figure 8 It is a field curvature curve diagram of the optical lens in the embodiment 2 of the present application.

[0031] Figure 9 It is an F-Theta distortion curve diagram of the optical lens in the embodiment 2 of the present application.

[0032] Figure 10 It is an axial aberration curve diagram of the optical lens in the embodiment 2 of the present application.

[0033] Figure 11 It is a lateral chromatic aberration curve diagram of the optical lens in the embodiment 2 of the present application.

[0034] Figure 12 It is an MTF curve diagram of the optical lens in the embodiment 2 of the present application.

[0035] Figure 13 It is a structural schematic diagram of the optical lens in the embodiment 3 of the present application.

[0036] Figure 14 Field curvature curve for the optical lens in Example 3 of the present application.

[0037] Figure 15 F-Theta distortion curve for the optical lens in Example 3 of the present application.

[0038] Figure 16 Axial aberration curve for the optical lens in Example 3 of the present application.

[0039] Figure 17 Tangential chromatic aberration curve for the optical lens in Example 3 of the present application.

[0040] Figure 18 MTF curve for the optical lens in Example 3 of the present application.

[0041] Figure 19 Structure schematic diagram of the optical lens in Example 4 of the present application.

[0042] Figure 20 Field curvature curve for the optical lens in Example 4 of the present application.

[0043] Figure 21 F-Theta distortion curve for the optical lens in Example 4 of the present application.

[0044] Figure 22 Axial aberration curve for the optical lens in Example 4 of the present application.

[0045] Figure 23 Tangential chromatic aberration curve for the optical lens in Example 4 of the present application.

[0046] Figure 24 MTF curve for the optical lens in Example 4 of the present application.

[0047] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0048] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be understood that the detailed description is merely descriptive of embodiments of the present application and is not intended to limit the scope of the present application in any way. Throughout the description, like reference numerals refer to like elements. The expression “and / or” includes any and all combinations of one or more of the associated listed items.

[0049] It should be noted that the terms first, second, third, etc. in the present specification are only used to distinguish one feature from another, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0050] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn strictly to scale.

[0051] In this context, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0052] It should also be understood that the terms "comprise", "comprising", "have", "having", "include", and / or "including" when used in this specification, indicate the presence of the stated features, elements and / or components but do not preclude the presence or addition of one or more other features, elements, components and / or groups thereof. In addition, when expressions such as "at least one of" appear after a list of one or more items, the phrase "at least one of" modifies the entire list of items and does not modify the individual items of the list. Furthermore, when describing embodiments of the present application, the use of "may" indicates that one or more embodiments of the present application. Also, the term "exemplary" is intended to mean an example or an illustration.

[0053] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that the terms should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0054] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0055] The optical lens provided by the embodiments of the present application has five lenses with optical power, which are sequentially arranged along the optical axis from the object side to the imaging surface as the first lens, the second lens, the third lens, the fourth lens, and the fifth lens.

[0056] In some embodiments, the first lens can have a negative focal power, the object side surface thereof can be convex, and the image side surface thereof can be concave. The second lens can have a positive focal power, the object side surface thereof can be convex, and the image side surface thereof can be convex. The third lens can have a positive focal power, the object side surface thereof can be concave, and the image side surface thereof can be convex. The fourth lens can have a positive focal power, the object side surface thereof can be convex, and the image side surface thereof can be convex at the near optical axis. The fifth lens can have a negative focal power, the object side surface thereof can be convex at the near optical axis, and the image side surface thereof can be concave at the near optical axis.

[0057] In some embodiments, the optical lens can further include a diaphragm, which can be located between the second lens and the third lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging.

[0058] In some embodiments, the optical lens can further include a filter and a protective glass, which are sequentially arranged between the fifth lens and the imaging surface along the optical axis. The filter is used to filter out interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging. The protective glass plays a role in protecting the optical lens, preventing the photosensitive chip from being damaged, and can improve the impact resistance and scratch resistance of the optical lens, while having little effect on the imaging quality of the optical lens.

[0059] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f35 of the third lens to the fifth lens satisfy: 3.6 < f12 / f35 < 5; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5.5 < TTL / f < 6.7. Satisfying the above range, the focal power ratio of the lens group before and after the diaphragm is reasonably limited, which is conducive to correcting the chromatic aberration and field curvature of the optical system, slowing down the light deflection angle, reducing the sensitivity, and reducing the difficulty of lens forming. At the same time, the length of the lens can be effectively limited, which is conducive to the miniaturization of the optical lens.

[0060] In some embodiments, the focal length f1 of the first lens and the combined focal length f12 of the first lens and the second lens satisfy: -0.25 < f1 / f12 < -0.18. Satisfying the above range, by reasonably configuring the combined focal length of the first lens and the second lens, the field curvature of the optical imaging lens system can be shortened, and the on-axis spherical aberration can be reduced.

[0061] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV of the optical lens, and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 45° < f x FOV / IH < 55°. Satisfying the above range, by reasonably limiting the relationship between the focal length, the field of view, and the image height of the optical lens, the optical lens has good optical performance.

[0062] In some embodiments, the first lens satisfies: 1 < (R1+R2) / (R1-R2) < 1.35. Satisfying the above range, the curvature radius of the object side surface and the image side surface of the first lens is reasonably controlled, which is conducive to controlling the shape of the first lens, so that the aberration introduced by the first lens is controlled within a reasonable range, thereby reducing the difficulty of correcting the aberration of the subsequent optical system and improving the imaging quality.

[0063] In some embodiments, the first lens satisfies: -1.8 < f1 / f < -1.5; the first lens satisfies: 7 < R1 / f < 10.5; and the first lens satisfies: 0.7 < R2 / f < 0.85. Satisfying the above range, the proportion of the refractive power of the first lens is controlled, which is conducive to the first lens receiving light rays with a large angle of incidence into the optical lens, expanding the field angle range of the optical lens, and also conducive to reducing the sensitivity of the optical lens and realizing the miniaturization design of the optical lens. At the same time, the first lens as a whole is in a meniscus shape with a concave surface facing the second side, which can make the light rays enter the rear optical system gently, thereby slowing down the trend of the edge light rays, which is conducive to reducing the incidence angle of the chief ray of each field of view and improving the imaging quality of the optical lens.

[0064] In some embodiments, the first lens satisfies: -0.8 < f1 / f2 < -0.65; and the second lens satisfies: 0.27 < f2 / f3 < 0.34. Satisfying the above range, the first lens and the second lens form chromatic aberration compensation, and help to compress the system length and balance the field curvature. At the same time, the refractive power of the second lens and the third lens is reasonably distributed, which is conducive to the correction of chromatic aberration and improves the resolution capability of the system.

[0065] In some embodiments, the fourth lens satisfies: -0.5 < (SAG42-SAG41) / CT4 < -0.35. Satisfying the above range, by controlling the relationship between the height difference of the sag of the image side surface and the object side surface of the fourth lens and the central thickness of the fourth lens, the shape of the fourth lens can be constrained, which is conducive to the design and processing of the structure of the fourth lens, conducive to correcting the aberration of each field of view respectively, and conducive to improving the imaging quality of the optical lens.

[0066] In some embodiments, the half-aperture radius of the object-side surface of the first lens DM11 and the half-aperture radius of the image-side surface of the fifth lens DM52 satisfy: 1.2 < DM11 / DM52 < 1.6. By satisfying the above range, by reasonably setting the ratio of the apertures of the first and last lenses, the lens has a smaller head size while having a larger imaging surface, which can better meet the balance of miniaturization and high pixels.

[0067] In some embodiments, the half-aperture radius of the object-side surface of the first lens DM11 and the focal length f1 of the first lens satisfy: 1.8 < DM11 / f1 < 2.3. By satisfying the above range, the lens shape of the first lens is reasonably controlled so that the light is incident on the object-side surface of the first lens at the maximum incident angle, realizing the wide-angle of the optical system.

[0068] In some embodiments, the Abbe number Vd4 of the fourth lens and the Abbe number Vd5 of the fifth lens satisfy: 29 < Vd4-Vd5 < 35. By satisfying the above range, the third lens uses a high Abbe coefficient and a low infrared dispersion material, which can reduce the focal shift and correct the infrared resolution. The third lens and the fourth lens use high and low Abbe coefficient lens pairing, which can offset the axial chromatic aberration, which is conducive to realizing clear imaging under infrared light.

[0069] In some embodiments, the focal length f1 of the first lens and the focal length f5 of the fifth lens satisfy: 0.25 < f1 / f5 < 0.34. By satisfying the above range, by reasonably setting the focal length relationship of the first and last lenses in the lens, the area of the light entering the imaging surface is increased while ensuring as much light as possible enters the system, which is conducive to realizing large imaging of the lens, while increasing the amount of light entering, improving the relative luminance of the system.

[0070] In some embodiments, the focal length f5 of the fifth lens and the combined focal length f35 of the third lens to the fifth lens satisfy: -3.7 < f5 / f35 < -2.7. By satisfying the above range, the power of the fifth lens is reasonably distributed, which is conducive to reducing the total length of the stop rear group lens, realizing the miniaturization of the entire zoom optical system.

[0071] In some embodiments, the distance BL on the optical axis from the image-side surface of the fifth lens to the imaging surface and the total optical length TTL of the optical lens satisfy: 0.16 < BL / TTL < 0.19. By satisfying the above range, it is conducive to realizing the short back focus of the optical lens, and in the case of ensuring sufficient space for optical element installation and focusing, it is conducive to realizing the miniaturization of the optical lens.

[0072] In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.7 < IH / f < 3.4. By satisfying the above range, by reasonably controlling the ratio of the image height and the focal length of the optical lens, it is conducive to realizing the ultra-wide-angle characteristic.

[0073] In some embodiments, the total track length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.7 < TTL / IH < 2.2. Satisfying the above range, the total length of the optical system is short, the lens structure is compact, and miniaturization is achieved.

[0074] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 2.1 < f2 / f < 2.5; the object side surface curvature radius R3 of the second lens and the effective focal length f of the optical lens satisfy: 2.6 < R3 / f < 3.1; and the image side surface curvature radius R4 of the second lens and the effective focal length f of the optical lens satisfy: -5.7 < R4 / f < -4.5. Satisfying the above range, the second lens has a large positive focal length, can converge the front end incident light, is beneficial to correcting the aberration and the edge field distortion caused by the front end lens, makes the lens have a small distortion, and can provide a high-definition imaging effect. At the same time, the second lens is a double convex lens, is beneficial to gently converging and collecting the front light beam, is beneficial to improving the imaging quality of the optical lens, and reduces the aperture of the rear fourth lens, thereby achieving miniaturization.

[0075] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 6.6 < f3 / f < 8.5; the object side surface curvature radius R5 of the third lens and the effective focal length f of the optical lens satisfy: -2.2 < R5 / f < -1.8; and the image side surface curvature radius R6 of the third lens and the effective focal length f of the optical lens satisfy: -1.7 < R6 / f < -1.4. Satisfying the above range, the third lens has a positive refractive power, and the aberration of the front and rear optical systems is complementary, thereby achieving high imaging quality of the optical lens. At the same time, reasonably setting the surface type of the third lens can adjust the trend of the light rays, and also helps to reduce the aperture of the subsequent lens, thereby achieving low cost.

[0076] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 1.7 < f4 / f < 2.1; the object side surface curvature radius R7 of the fourth lens and the effective focal length f of the optical lens satisfy: 5.3 < R7 / f < 6.5; and the image side surface curvature radius R8 of the fourth lens and the effective focal length f of the optical lens satisfy: -1.3 < R8 / f < -1. Satisfying the above range, the effective focal length of the fourth lens is guaranteed to be within a certain range, which is beneficial to achieving high imaging quality. At the same time, the already converged light beam can be effectively converged and collected, which is helpful to high imaging quality and reduces the difficulty of lens forming and processing.

[0077] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -6.5 < f5 / f < -4.7; the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 1.4 < R9 / f < 1.7; and the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.9 < R10 / f < 1.1. Satisfying the above ranges, the fifth lens cooperates with the fourth lens to correct the image surface curvature, ensures the clarity of the edge and the center at the same time, balances various aberrations generated by the front group of lenses, and improves the imaging quality of the optical lens. Meanwhile, reasonably setting the radii of curvature of the object side surface and the image side surface of the fifth lens is conducive to balancing the aberrations generated by the front end lenses, collecting the light rays of the edge field of view, improving the imaging quality of the edge field of view, and increasing the imaging area of the optical lens.

[0078] In some embodiments, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 23° / mm < FOV / IH < 29° / mm. Satisfying the above range, under the premise of meeting the image height requirement, the optical lens can have a large field of view, thereby having good optical performance and capturing details of the object well.

[0079] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 65° < FOV / Fno < 88°. Satisfying the above range is conducive to expanding the field of view of the optical lens and increasing the aperture of the optical lens, thereby realizing the characteristics of wide angle and large aperture of the lens.

[0080] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the aperture value Fno of the optical lens satisfy: 2.5 mm < IH / Fno < 3.3 mm. Satisfying the above range can improve the edge brightness of the lens, improve the relative luminance of the entire optical system, and optimize the imaging quality.

[0081] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 5.5 < IH / EPD < 7. Satisfying the above range enables the optical lens to meet the large image surface while also meeting the sufficient image surface brightness of the edge field of view, thereby preventing the occurrence of dark corner phenomenon and improving the imaging quality.

[0082] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: 9 < R1 / R2 < 13. Satisfying the above range reasonably sets the surface shape of the first lens, enhances the collection ability of the first lens to light rays, and thereby realizes a large field of view.

[0083] In some embodiments, the object-side surface curvature radius R3 of the second lens and the image-side surface curvature radius R4 of the second lens satisfy: -0.33 < (R3+R4) / (R3-R4) < -0.26. Satisfying the above range is conducive to the contraction of the light rays of the wide-angle field of view, thereby adjusting the trend of the marginal light beam and ensuring that the optical lens has a larger field of view angle.

[0084] In some embodiments, the object-side surface curvature radius R9 of the fifth lens and the image-side surface curvature radius R10 of the fifth lens satisfy: 4 < (R9+R10) / (R9-R10) < 5.2. Satisfying the above range reasonably limits the surface shape of the fifth lens, which helps to control the trend of the light rays of the marginal field of view and improve the imaging quality of the marginal field of view.

[0085] In some embodiments, the central thickness CT1 of the first lens and the central thickness CT2 of the second lens satisfy: 33 < CT1 / CT2 < 54; and the central thickness CT2 of the second lens and the central thickness CT3 of the third lens satisfy: 1.1 < CT2 / CT3 < 1.5. Satisfying the above range can improve the stability of the lens and reduce temperature drift.

[0086] In some embodiments, the central thickness CT3 of the third lens and the central thickness CT4 of the fourth lens satisfy: 0.4 < CT3 / CT4 < 0.54. Satisfying the above range reasonably configures the ratio of the thickness of the third lens on the optical axis and the thickness of the fourth lens on the optical axis, and the third lens and the fourth lens can regulate each other while maintaining the characteristics of miniaturization of the optical system.

[0087] In some embodiments, the central thickness CT4 of the fourth lens and the central thickness CT5 of the fifth lens satisfy: 3.2 < CT4 / CT5 < 4. Satisfying the above range reasonably sets the thickness relationship of the fourth and fifth lenses, so that the central thickness satisfies the requirements of assembly stability while reducing the assembly deformation and ghost reflection energy of the lens and improving the imaging quality.

[0088] In some embodiments, the sum ΣCT of the central thicknesses of the five lenses and the total optical length TTL of the optical lens satisfy: 0.38 < ΣCT / TTL < 0.48. Satisfying the above range can effectively compress the total length of the lens, while being conducive to the structural design and production process of the lens.

[0089] In some embodiments, the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, and the focal length f3 of the third lens satisfy: 0.14 < (CT2+CT3) / f3 < 0.19. Satisfying the above range, the second lens and the third lens form a thick lens group, form a higher positive refractive power, and undertake the main convergence task, which helps to improve the structural stability and optical performance.

[0090] In some embodiments, the image-side half-aperture sagittal height of the fifth lens SAG52, the object-side half-aperture sagittal height of the fifth lens SAG51, and the central thickness of the fifth lens CT5 satisfy: -0.17 < (SAG52-SAG51) / CT5 < 0.1. By satisfying the above range, by controlling the height difference between the sagittal heights of the image side and the object side of the fifth lens and the central thickness of the fifth lens, the coma of the off-axis field of view is corrected, and the imaging quality of the optical lens off-axis field of view is improved.

[0091] In some embodiments, the object-side half-aperture diameter of the first lens DM11 and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.6 < DM11 / IH < 0.75. By satisfying the above range, the balance between the front end aperture of the optical lens and the image size can be ensured.

[0092] In some embodiments, the object-side curvature radius of the first lens R1, the image-side curvature radius of the first lens R2, and the central thickness of the first lens CT1 satisfy: 5.2 < R1 / (R2+CT1) < 7.2. By satisfying the above range, the correction difficulty of the edge field distortion can be reduced, and the distortion is controlled within a reasonable range.

[0093] In some embodiments, the image-side half-aperture diameter of the first lens DM12 and the image-side curvature radius of the first lens R2 satisfy: 0.63 < 2*DM12 / R2 < 0.78. By satisfying the above range, the lens can avoid being super-hemispherical, and the processing difficulty of the first lens is greatly reduced.

[0094] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view angle of the optical lens satisfy: 1 < (IH / 2) / (f*θ) < 1.25. By satisfying the above range, small distortion can be better achieved.

[0095] In some embodiments, the optical lens satisfies the following conditional expressions: 1.8 mm < f < 2.2 mm; 140° < FOV < 170°; 10 mm < TTL < 14 mm; 1.8 < Fno < 2.3; 5.2 mm < IH < 6.7 mm; 15° < CRA < 24°. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field of view angle of the optical lens, and CRA represents the chief ray incidence angle at the maximum image height of the optical lens. By satisfying the above range, the optical lens can be suitable for the infrared light waveband, and has one or more advantages such as large field of view angle, large image, high imaging quality, etc.

[0096] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristics of the glass itself. The optical lens provided by the present application adopts a five-piece lens structure composed of glass and plastic. More specifically, the first lens, the third lens, the fourth lens, and the fifth lens can be plastic lenses, and the second lens can be a glass lens. The glass-plastic hybrid structure can improve the thermal stability, effectively reduce the cost, correct the aberration, reduce the size, and provide an optical lens product with higher performance-price ratio.

[0097] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, and the fifth lens can be spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization. More specifically, the first lens, the third lens, the fourth lens, and the fifth lens in the optical lens provided by the present application can be aspherical lenses, and the second lens can be a spherical lens.

[0098] In various embodiments of the present application, when the lens is an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[0099]

[0100] wherein z is the distance of the curved surface from the vertex of the curved surface in the direction of the optical axis, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic surface coefficient, and B, C, D, E, F, and G are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, and fourteenth-order surface coefficients, respectively.

[0101] The present application will be further described in the following embodiments. In various embodiments, the thickness, the radius of curvature, and the material selection of each lens in the optical lens are different, and the specific differences can be referred to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present application, but the embodiments of the present application are not limited to the following embodiments, and any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present application should be regarded as equivalent replacement methods, and all are included in the protection scope of the present application.

[0102] Embodiment 1

[0103] Please refer to Figure 1Fig. 1 is a structural schematic diagram of an optical lens 100 provided in Embodiment 1 of the present application, which comprises, in sequence from the object side to the imaging surface along the optical axis, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a filter G1 and a protective glass G2.

[0104] wherein,

[0105] The first lens L1 has negative focal power, the object side S1 is a convex surface, and the image side S2 is a concave surface;

[0106] The second lens L2 has positive focal power, the object side S3 is a convex surface, and the image side S4 is a convex surface;

[0107] The third lens L3 has positive focal power, the object side S5 is a concave surface, and the image side S6 is a convex surface;

[0108] The fourth lens L4 has positive focal power, the object side S7 is a convex surface, and the image side S8 is a convex surface near the optical axis;

[0109] The fifth lens L5 has negative focal power, the object side S9 is a convex surface near the optical axis, and the image side S10 is a concave surface near the optical axis;

[0110] The object side S11 and the image side S12 of the filter G1 are both flat surfaces;

[0111] The object side S13 and the image side S14 of the protective glass G2 are both flat surfaces;

[0112] The imaging surface S15 is a flat surface.

[0113] The first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are plastic aspheric lenses, and the second lens L2 is a glass spherical lens.

[0114] The related parameters of the lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0115] Table 1-1

[0116]

[0117]

[0118] The surface type parameters of the aspheric lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0119] Table 1-2

[0120] Surface Number K B C D E F G S1 -1.00E+02 -4.01E-04 -6.79E-06 3.87E-06 -2.11E-07 2.19E-09 0.00E+00 S2 -9.23E-01 -6.00E-04 1.07E-02 -5.84E-03 1.67E-03 -1.83E-04 0.00E+00 S5 -2.17E+01 -5.96E-02 5.34E-02 -7.25E-02 6.58E-02 -2.50E-02 0.00E+00 S6 2.01E+00 1.01E-02 6.64E-03 -1.54E-03 8.87E-04 -1.41E-04 0.00E+00 S7 1.67E+01 6.32E-03 1.86E-03 1.96E-04 -1.02E-04 9.52E-06 0.00E+00 S8 -5.18E+00 -1.83E-02 6.27E-03 5.32E-04 -2.43E-04 5.13E-05 0.00E+00 S9 -2.72E+00 -3.50E-02 1.38E-03 3.86E-04 4.70E-05 -9.96E-06 2.21E-08 S10 -3.91E+00 -2.72E-02 6.32E-04 1.71E-04 6.39E-05 -1.20E-05 3.71E-07

[0121] In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, the transverse chromatic aberration curve, and the MTF curve of the optical lens 100 are shown in FIGS. 1-4, respectively. Figures 2 to 6

[0122] Figure 2 The field curvature curve of Example 1 is shown, which represents the curvature of light rays of different wavelengths on the meridional image surface and the sagittal image surface, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image surface and the sagittal image surface is controlled within -0.06mm~0.04mm, which shows that the optical lens 100 can well correct the field curvature.

[0123] Figure 3 The F-Theta distortion curve of Example 1 is shown, which represents the distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within 0%~20%, which shows that the optical lens 100 can well correct the distortion.

[0124] Figure 4 The axial aberration curve of Example 1 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. It can be seen from the figure that the offset of the axial aberration is controlled within -0.01mm~0.02mm, which shows that the optical lens 100 can well correct the axial aberration.

[0125] Figure 5 The transverse chromatic aberration curve of Example 1 is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.940μm) at different image heights on the imaging surface, the horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3μm~2μm, which shows that the optical lens 100 can very well correct the chromatic aberration of the edge field and the secondary spectrum of the entire image surface.

[0126] Figure 6 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the lens imaging modulation degree of different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of the present embodiment is above 0.3 within the full field of view, and within the range of 0~120lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in low frequency and high frequency cases.

[0127] ​Embodiment 2

[0128] Please refer to Figure 7 , which is a structural schematic diagram of the optical lens 200 provided in Embodiment 2 of the present application. Compared with Embodiment 1, the main difference is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0129] The related parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0130] Table 2-1

[0131]

[0132] The surface type parameters of the aspherical lens of the optical lens 200 in Embodiment 2 are shown in Table 2-2.

[0133] Table 2-2

[0134]

[0135]

[0136] In this embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, the transverse chromatic aberration curve and the MTF curve of the optical lens 200 are shown in Figures 8 to 12 , respectively.

[0137] As can be seen from Figure 8 , the field curvature of the meridional image surface and the sagittal image surface is controlled within-0.06mm-0.04mm, which shows that the optical lens 200 can well correct the field curvature. As can be seen from Figure 9 , the distortion of the optical lens is controlled within 0%-20%, which shows that the optical lens 200 can well correct the distortion. As can be seen from Figure 10 , the shift of the axial aberration is controlled within-0.01mm-0.02mm, which shows that the optical lens 200 can well correct the axial aberration. As can be seen from Figure 11 , the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2μm, which shows that the optical lens 200 can very well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image surface. As can be seen from Figure 12 , the MTF value of this embodiment is above 0.3 in the full field of view, and in the range of 0-120lp / mm, the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0138] Embodiment 3

[0139] Please refer to Figure 13The figure shown is a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0140] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0141] Table 3-1

[0142]

[0143]

[0144] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0145] Table 3-2

[0146] Surface Number K B C D E F G S1 -1.00E+02 -5.46E-04 -9.79E-06 3.95E-06 -2.03E-07 2.74E-09 0.00E+00 S2 -9.08E-01 1.07E-04 1.07E-02 -5.95E-03 1.63E-03 -1.72E-04 0.00E+00 S5 -2.25E+01 -6.03E-02 5.19E-02 -7.04E-02 7.00E-02 -3.06E-02 0.00E+00 S6 2.02E+00 1.05E-02 6.28E-03 -1.08E-03 9.89E-04 -3.00E-04 0.00E+00 S7 1.50E+01 6.64E-03 1.81E-03 2.02E-04 -9.94E-05 9.29E-06 0.00E+00 S8 -4.89E+00 -1.93E-02 6.18E-03 5.36E-04 -2.42E-04 4.91E-05 0.00E+00 S9 -2.83E+00 -3.55E-02 1.28E-03 3.76E-04 4.65E-05 -9.86E-06 8.42E-08 S10 -3.84E+00 -2.70E-02 6.24E-04 1.66E-04 6.40E-05 -1.19E-05 4.01E-07

[0147] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 300 are respectively as follows: Figures 14 to 18 As shown.

[0148] from Figure 14 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.06mm to 0.04mm, indicating that the optical lens 300 can effectively correct field curvature. From Figure 15 As can be seen, the distortion of the optical lens is controlled within 0% to 20%, indicating that the optical lens 300 can effectively correct distortion. From... Figure 16 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens 300 can effectively correct axial aberration. From Figure 17 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -3μm to 2μm, indicating that the optical lens 300 can excellently correct chromatic aberration at the edge of the field of view and the second-order spectrum of the entire image plane. From Figure 18 As can be seen, the MTF value of this embodiment is above 0.2 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0149] Example 4

[0150] Please see Figure 19The figure shown is a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0151] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0152] Table 4-1

[0153]

[0154]

[0155] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0156] Table 4-2

[0157] Surface Number K B C D E F G S1 -1.00E+02 -4.17E-04 -7.61E-06 3.86E-06 -2.09E-07 2.93E-09 0.00E+00 S2 -9.10E-01 -6.84E-04 1.07E-02 -5.83E-03 1.68E-03 -1.83E-04 0.00E+00 S5 -2.27E+01 -5.99E-02 5.36E-02 -7.23E-02 6.64E-02 -2.59E-02 0.00E+00 S6 1.99E+00 1.05E-02 6.66E-03 -1.55E-03 8.67E-04 -1.49E-04 0.00E+00 S7 1.67E+01 6.31E-03 1.85E-03 1.95E-04 -1.02E-04 9.51E-06 0.00E+00 S8 -5.33E+00 -1.81E-02 6.25E-03 5.25E-04 -2.43E-04 5.15E-05 0.00E+00 S9 -2.74E+00 -3.50E-02 1.50E-03 3.85E-04 4.67E-05 -1.01E-05 1.66E-08 S10 -3.83E+00 -2.74E-02 5.77E-04 1.66E-04 6.40E-05 -1.21E-05 3.64E-07

[0158] In this embodiment, the field curvature curve, F-Theta distortion curve, axial aberration curve, transverse chromatic aberration curve, and MTF curve of the optical lens 400 are respectively as follows: Figures 20 to 24 As shown.

[0159] from Figure 20 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.06mm to 0.04mm, indicating that the optical lens 400 can effectively correct field curvature. From Figure 21 As can be seen, the distortion of the optical lens is controlled within 0% to 15%, indicating that the optical lens 400 can effectively correct distortion. From... Figure 22 As can be seen, the axial aberration offset is controlled within ±0.01mm, indicating that the optical lens 400 can effectively correct axial aberration. From Figure 23 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2μm, indicating that the optical lens 400 can excellently correct chromatic aberration at the edge of the field of view and the second-order spectrum of the entire image plane. From Figure 24 As can be seen, the MTF value of this embodiment is above 0.3 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0160] Please refer to Table 5 for the optical characteristics of the above-mentioned embodiments, including the effective focal length f, the total track length TTL, the aperture value Fno, the chief ray angle of incidence CRA at the maximum image height, the real image height IH corresponding to the maximum field of view angle, the maximum field of view angle FOV of the optical lens, and the numerical value corresponding to each conditional expression in the embodiments.

[0161] Table 5

[0162]

[0163]

[0164] In summary, the optical lens provided by the present application has five pieces of lenses with refractive power, and through specific surface shape matching and reasonable refractive power distribution, the optical lens can be applied to the infrared light waveband, the imaging quality of the optical lens can be improved, the aberration can be reduced, the imaging quality of the optical lens can be improved, and the lens has one or more advantages such as a large field of view angle, a large image surface, and high imaging quality.

[0165] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily mean the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0166] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the present patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present patent should be subject to the appended claims.

Claims

1. An optical lens comprising five lenses having optical power, characterized in that, It successively includes from the object side to the imaging surface along the optical axis: A first lens with negative optical power, whose object side is convex and whose image side is concave; A second lens with positive optical power, whose object side is convex and whose image side is convex; A third lens with positive optical power, whose object side is concave and whose image side is convex; A fourth lens with positive optical power, whose object side is convex and whose image side is convex near the optical axis; A fifth lens with negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; Among them, the combined focal length f12 of the first lens and the second lens and the combined focal length f35 of the third lens to the fifth lens satisfy: 3.6 < f12 / f35 < 5; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy:

5. < TTL / f < 6.

7.

2. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens and the combined focal length f12 of the first lens and the second lens satisfy: -0.25 < f1 / f12 < -0.

18.

3. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens, the maximum field angle FOV of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 45° < f×FOV / IH < 55°.

4. The optical lens according to claim 1, characterized in that, The curvature radius R1 of the object side of the first lens and the curvature radius R2 of the image side of the first lens satisfy: 1 < (R1 + R2) / (R1 - R2) < 1.

35.

5. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.8 < f1 / f < -1.5; the curvature radius R1 of the object side of the first lens and the effective focal length f of the optical lens satisfy: 7 < R1 / f < 10.5; the curvature radius R2 of the image side of the first lens and the effective focal length f of the optical lens satisfy: 0.7 < R2 / f < 0.

85.

6. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.8 < f1 / f2 < -0.65; the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: 0.27 < f2 / f3 < 0.

34.

7. The optical lens according to claim 1, characterized in that, The sagittal height SAG42 of the image side clear aperture semi-diameter, the sagittal height SAG41 of the object side clear aperture semi-diameter of the fourth lens and the central thickness CT4 of the fourth lens satisfy: -0.5 < (SAG42 - SAG41) / CT4 < -0.

35.

8. The optical lens according to claim 1, characterized in that, The clear aperture semi-diameter DM11 of the object side of the first lens and the clear aperture semi-diameter DM52 of the image side of the fifth lens satisfy: 1.2 < DM11 / DM52 < 1.

6.

9. The optical lens according to claim 1, characterized in that, The clear aperture semi-diameter DM11 of the object side of the first lens and the focal length f1 of the first lens satisfy: 1.8 < DM11 / f1 < 2.

3.

10. The optical lens according to claim 1, characterized in that, The Abbe number Vd4 of the fourth lens and the Abbe number Vd5 of the fifth lens satisfy: 29 < Vd4 - Vd5 < 35.

Images