Optical lens

Abstract

The application discloses an optical lens, which comprises, in sequence from an object side to an imaging surface along an optical axis, an aperture stop, a first lens with positive refractive power, an object side of which is a convex surface, a second lens with negative refractive power, an image side of which is a concave surface, a third lens with negative refractive power, an object side of which is a concave surface near the optical axis, an image side of which is a convex surface near the optical axis, a fourth lens with refractive power, an object side of which is a concave surface, an image side of which is a convex surface, a fifth lens with negative refractive power, an object side of which is a concave surface, an image side of which is a convex surface, and a sixth lens with negative refractive power, an object side of which is a concave surface, an image side of which is a convex surface, wherein the total optical length of the optical lens satisfies TTL < 4.0 mm. The optical lens has the advantages of short total optical length, high pixels and small distortion.

Description

Technical Field

[0001] This invention relates to the field of imaging lens technology, and in particular to an optical lens. Background Technology

[0002] With the rapid development of mobile internet and the popularity of social media, video, and live streaming apps, people are increasingly inclined to communicate via video when conditions permit. As an emerging electronic product, smartwatches have attracted much attention, and with the introduction of video functionality, they have been widely adopted in the children's market. At the same time, consumer demand for smartwatches is also increasing, with consumers seeking not only a thinner and lighter wearing experience but also higher-definition imaging effects.

[0003] Because existing imaging lenses generally have a long optical length, electronic products using these lenses cannot be made thinner, which greatly affects the wearing experience. At the same time, the effective focal length of the lenses is short, resulting in poor imaging quality, making it difficult for these lenses to meet the needs of the smartwatch industry. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide an optical lens that has at least the advantages of short total optical length and high pixel count.

[0005] This invention provides an optical lens comprising, along the optical axis from the object side to the imaging plane, the following components in sequence: an aperture stop; a first lens with positive optical power, the object side of which is convex; a second lens with negative optical power, the image side of which is concave; a third lens with negative optical power, the object side of which is concave near the optical axis and the image side of which is convex near the optical axis; a fourth lens with optical power, the object side of which is concave and the image side of which is convex; a fifth lens with negative optical power, the object side of which is concave and the image side of which is convex; and a sixth lens with negative optical power, the object side of which is concave and the image side of which is convex; wherein the total optical length of the optical lens satisfies: TTL < 4.0 mm.

[0006] Compared to existing technologies, the optical lens provided by this invention employs a reasonable combination of six lenses with specific optical power and surface shape, giving it the advantages of short total optical length and long focal length. This enables high-definition imaging with minimal distortion and high fidelity. Furthermore, by rationally configuring the spacing between the lenses and controlling the total optical length, the space occupied by the lens within electronic products can be significantly reduced, increasing the optimization space for the product's structure, making it thinner and lighter, and better meeting the current market demand for lenses in the smartwatch industry. Attached Figure Description

[0007] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0008] Figure 1 This is a schematic diagram of the structure of the optical lens according to the first embodiment of the present invention;

[0009] Figure 2 This is a field curvature curve diagram of the optical lens according to the first embodiment of the present invention;

[0010] Figure 3 This is a distortion curve diagram of the optical lens according to the first embodiment of the present invention;

[0011] Figure 4 This is an axial chromatic aberration curve of the optical lens in the first embodiment of the present invention;

[0012] Figure 5 This is a chromatic aberration curve of the optical lens in the first embodiment of the present invention;

[0013] Figure 6 This is a schematic diagram of the structure of the optical lens according to the second embodiment of the present invention;

[0014] Figure 7 This is a field curvature curve diagram of the optical lens according to the second embodiment of the present invention;

[0015] Figure 8 This is a distortion curve diagram of the optical lens according to the second embodiment of the present invention;

[0016] Figure 9 This is an axial chromatic aberration curve of the optical lens in the second embodiment of the present invention;

[0017] Figure 10 This is a chromatic aberration curve of the optical lens in the second embodiment of the present invention;

[0018] Figure 11 This is a schematic diagram of the optical lens structure according to the third embodiment of the present invention;

[0019] Figure 12 This is a field curvature curve diagram of the optical lens according to the third embodiment of the present invention;

[0020] Figure 13 This is a distortion curve diagram of the optical lens according to the third embodiment of the present invention;

[0021] Figure 14 This is an axial chromatic aberration curve of the optical lens in the third embodiment of the present invention;

[0022] Figure 15 This is a chromatic aberration curve of the optical lens in the third embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present invention will be thorough and complete.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Throughout this specification, the same reference numerals refer to the same elements.

[0025] The present invention provides an optical lens, which includes, in sequence along the optical axis from the object side to the imaging plane: an aperture stop, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a filter.

[0026] The first lens has positive optical power, with its object side being convex and its image side being either concave or convex; the second lens has negative optical power, with its object side being either convex or concave and its image side being concave; the third lens has negative optical power, with its object side being concave near the optical axis and its image side being convex near the optical axis; the fourth lens has optical power, with its object side being concave and its image side being convex; the fifth lens has negative optical power, with its object side being concave and its image side being convex; and the sixth lens has optical power, with its object side being concave and its image side being convex.

[0027] As one implementation, the optical lens satisfies the following condition:

[0028] TTL < 4.0 mm; (1)

[0029] 0.55 < IH / TTL < 0.65; (2)

[0030] Wherein, IH represents the image height corresponding to the maximum half field of view of the optical lens, and TTL represents the total optical length of the optical lens. By satisfying the above conditions (1) and (2), the imaging quality of the lens can be guaranteed while meeting the requirements of the imaging range, and the total optical length of the optical lens can be coordinated, so that the optical lens has the characteristic of short total optical length.

[0031] As one implementation, the optical lens satisfies the following condition:

[0032] 4.2 mm / rad<IH / θ<4.6 mm / rad; (3)

[0033] Where θ represents the maximum half-field angle of the optical lens, and IH represents the image height corresponding to the maximum half-field angle of the optical lens. Satisfying the above condition (3) not only enables the optical lens to meet the imaging range requirements, but also enables the optical lens to have small optical distortion, and enables both the edge field of view and the center field of view of the optical lens to have high imaging quality.

[0034] As one implementation, the optical lens satisfies the following condition:

[0035] 0 < (f1 + f2) / f3 < 0.2; (4)

[0036] Where f1 represents the effective focal length of the first lens, f2 represents the effective focal length of the second lens, and f represents the effective focal length of the third lens. By satisfying the above condition (4) and reasonably coordinating the ratio of the effective focal lengths of the first lens, the second lens, and the third lens, the distortion of the optical system can be better balanced, the distortion value of the edge field of view can be reduced, and the imaging quality of the entire field of view can be improved.

[0037] In one embodiment, the second lens has negative optical power, and the optical lens satisfies the following condition:

[0038] 1.0 < R32 / R31 < 1.5; (5)

[0039] Wherein, R31 represents the radius of curvature of the object side of the third lens, and R32 represents the radius of curvature of the image side of the third lens. By satisfying the above condition (5) and reasonably setting the surface shape of the third lens, it is beneficial to control the exit angle of the light rays emitted from the third lens, so that the light beam can be transmitted to the imaging surface more effectively, thereby giving the optical lens a larger imaging surface.

[0040] As one implementation, the optical lens satisfies the following condition:

[0041] 1.5<(AC34+CT3) / CT4<2.5; (6)

[0042] 9<TTL / (CT3+AC34)<11; (7)

[0043] Where AC34 represents the air gap between the third lens and the fourth lens on the optical axis, CT3 represents the center thickness of the third lens, CT4 represents the center thickness of the fourth lens, and TTL represents the total optical length of the optical lens. By satisfying the above conditions (6) and (7), and by reasonably adjusting the center thickness of the third lens and the fourth lens as well as the air gap between the third lens and the fourth lens, it is beneficial to improve the MTF of the optical lens, thereby improving the overall image quality of the optical lens.

[0044] As one implementation, the optical lens satisfies the following condition:

[0045] -0.5<(R31-R32) / (R31+R32)<0; (8)

[0046] -13 < f3 / f < -4; (9)

[0047] Wherein, R31 represents the radius of curvature of the object side of the third lens, R32 represents the radius of curvature of the image side of the third lens, f represents the effective focal length of the optical lens, and f3 represents the effective focal length of the third lens. By satisfying the above conditions (8) and (9) and reasonably controlling the optical power and surface shape of the third lens, the diverged light rays can enter the rear system more smoothly, reducing the difficulty of aberration correction.

[0048] As one implementation, the optical lens satisfies the following condition:

[0049] -3.0 < f5 / f < -2.0; (10)

[0050] -5.5<(R51+R52) / (R51-R52)<-3.5; (11)

[0051] 14 < CT5 / AC56 < 17; (12)

[0052] Wherein, f5 represents the effective focal length of the fifth lens, f represents the effective focal length of the optical lens, R51 represents the radius of curvature of the object side of the fifth lens, R52 represents the radius of curvature of the image side of the fifth lens, CT5 represents the center thickness of the fifth lens, and AC56 represents the air gap between the fifth lens and the sixth lens on the optical axis. Satisfying the above conditions (10) to (12) can give the fifth lens a suitable optical power and surface shape, which is beneficial to balancing the astigmatism and aberration of the optical system and improving the imaging quality of the optical lens.

[0053] As one implementation, the optical lens satisfies the following condition:

[0054] 0.5 < CT4 / AC45 < 0.7; (13)

[0055] 0<(CT4+AC45) / TTL<0.5; (14)

[0056] Wherein, CT4 represents the center thickness of the fourth lens, AC45 represents the air gap between the fourth lens and the fifth lens on the optical axis, and TTL represents the total optical length of the optical lens. By satisfying the above conditions (13) and (14) and reasonably adjusting the thickness of the fourth lens, light rays can be better converged, the difficulty of aberration correction can be reduced, and the imaging quality can be improved, thus enhancing the imaging quality of the optical lens.

[0057] In one embodiment, the optical lens satisfies the following condition:

[0058] 0.9 < DM2 / DM3 < 1.0; (15)

[0059] Wherein, DM2 represents the optical effective diameter of the second lens, and DM3 represents the optical effective diameter of the third lens. Satisfying the above condition (15) ensures that the light beam entering the optical system through the second lens is transmitted to the rear lens to the maximum extent via the third lens, reducing the loss of light beam energy and improving image quality.

[0060] In one embodiment, the optical lens satisfies the following condition:

[0061] 0 < BFL / IH < 0.5; (16)

[0062] 4.5 < TTL / BFL < 5.5; (17)

[0063] Wherein, IH represents the image height corresponding to the maximum half field of view of the optical lens, TTL represents the total optical length of the optical lens, and BFL represents the optical back focal length of the optical lens. By satisfying the above conditions (16) and (17), and by reasonably controlling the ratio of the total optical length to the back focal length of the optical lens, as well as the ratio of the optical back focal length to the image height, the total length of the optical lens and the telephoto effect can be well balanced.

[0064] In one embodiment, the optical lens satisfies the following condition:

[0065] -28<(R41+R42) / (R41-R42)<22; (18)

[0066] Wherein, R41 represents the radius of curvature of the object side of the fourth lens, and R42 represents the radius of curvature of the image side of the fourth lens. Satisfying the above condition (18), by reasonably controlling the surface shape of the fourth lens, it is beneficial to improve the component tolerance, thereby improving the production yield of optical lenses.

[0067] In one implementation, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens can all be aspherical lenses, or they can be a combination of spherical and aspherical lenses; optionally, all of the above lenses are aspherical lenses, which can effectively reduce the number of lenses, correct aberrations, and provide better optical performance.

[0068] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0069] In various embodiments of the present invention, when the lens in the optical lens is an aspherical lens, the aspherical surface shape of the lens satisfies the following equation:

[0070]

[0071] Where z represents the distance vector from the aspherical surface to the vertex along the optical axis at a height of h, c is the paraxial curvature of the surface, k is the quadratic surface coefficient, and A 2i is the aspherical surface shape coefficient of the 2ith order.

[0072] First Embodiment

[0073] Please refer to Figure 1 The diagram shows a schematic of the structure of an optical lens 100 provided in the first embodiment of the present invention. The optical lens 100 consists of the following components along the near-optical axis from the object side to the imaging surface S15: aperture ST, first lens L1, second lens L2, third lens L3, fourth lens L4, fifth lens L5, sixth lens L6, and filter G1.

[0074] The first lens L1 has positive optical power, its object-side surface S1 is convex, and its image-side surface S2 is concave. The second lens L2 has negative optical power, its object-side surface S3 is convex, and its image-side surface S4 is concave. The third lens L3 has negative optical power, its object-side surface S5 is concave near the optical axis, and its image-side surface S6 is convex near the optical axis. The fourth lens L4 has negative optical power, its object-side surface S7 is concave, and its image-side surface S8 is convex. The fifth lens L5 has negative optical power, its object-side surface S9 is concave, and its image-side surface S10 is convex. The sixth lens L6 has negative optical power, its object-side surface S11 is concave, and its image-side surface S12 is convex. The filter G1 has an object-side surface S13 and an image-side surface S14.

[0075] To better correct aberrations in the optical system, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are all made of plastic aspherical lenses.

[0076] Specifically, the design parameters of the optical lens 100 provided in this embodiment are shown in Table 1.

[0077] Table 1

[0078]

[0079] In this embodiment, the aspherical parameters of each lens in the optical lens 100 are shown in Table 2.

[0080] Table 2

[0081]

[0082] Please refer to Figure 2 , Figure 3 , Figure 4 and Figure 5 The figures shown are the field curvature curve, distortion curve, axial chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 100.

[0083] Figure 2 The field curvature curve represents the degree of curvature of the meridional image plane and the sagittal image plane. Among them, Figure 2 The horizontal axis represents the offset (unit: mm), and the vertical axis represents the field of view (unit: degrees). From Figure 2 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.10mm, indicating that the field curvature correction of the optical lens 100 is good.

[0084] Figure 3 The distortion curve represents the distortion at different image heights on the imaging plane. Among them, Figure 3The horizontal axis represents the percentage of distortion, and the vertical axis represents the field of view (unit: degrees). From Figure 3 As can be seen, the distortion at different image heights on the imaging plane is controlled within ±2%, indicating that the distortion of the optical lens 100 is well corrected.

[0085] Figure 4 The axial chromatic aberration curve represents the aberration along the optical axis at the imaging plane. Among them, Figure 4 The horizontal axis represents the sphere value (unit: mm), and the vertical axis represents the normalized pupil radius. From Figure 4 As can be seen, the axial chromatic aberration offset is controlled within ±0.025mm, indicating that the axial chromatic aberration of the optical lens 100 is well corrected.

[0086] Figure 5 The transverse chromatic aberration curve represents the chromatic aberration between the longest and shortest wavelengths at different image heights on the imaging plane. Among them, Figure 5 The horizontal axis represents the transverse chromatic difference value (unit: micrometers) of each wavelength relative to the center wavelength, and the vertical axis represents the normalized field of view. From Figure 5 As can be seen, the transverse chromatic aberration between the longest and shortest wavelengths is controlled within ±2.5 micrometers, indicating that the optical lens 100 can effectively correct aberrations in the edge field of view and the secondary spectrum of the entire image plane.

[0087] Second Embodiment

[0088] Please see Figure 6 The figure shows a schematic diagram of the structure of the optical lens 200 provided in the second embodiment of the present invention. The optical lens 200 provided in this embodiment has a structure that is roughly the same as that of the optical lens 100 provided in the first embodiment. The main difference is that the image side S2 of the first lens is a convex surface, the object side S3 of the second lens is a concave surface, the fourth lens L4 has positive optical power, and the curvature radius and lens thickness of each lens are different.

[0089] The relevant parameters of each lens element in the optical lens 200 provided in this embodiment are shown in Table 3.

[0090] Table 3

[0091]

[0092]

[0093] The surface coefficients of each aspherical surface of the optical lens 200 in this embodiment are shown in Table 4.

[0094] Table 4

[0095]

[0096] Please refer to Figure 7 , Figure 8 , Figure 9 and Figure 10 The figures shown are the field curvature curve, distortion curve, axial chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 200.

[0097] Figure 7 The field curvature curve represents the degree of curvature of the meridional and sagittal image planes. From Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.07mm, indicating that the field curvature correction of the optical lens 200 is good.

[0098] Figure 8 The distortion curve represents the distortion at different image heights on the imaging plane. From Figure 8 As can be seen, the distortion at different image heights on the imaging plane is controlled within ±1.5%, indicating that the distortion of the optical lens 200 is well corrected.

[0099] Figure 9 The axial chromatic aberration curve represents the aberrations along the optical axis at the imaging plane. From Figure 9 As can be seen, the axial chromatic aberration offset is controlled within ±0.02mm, and the chromatic aberration curve is relatively concentrated, indicating that the axial chromatic aberration of the optical lens 200 is well corrected.

[0100] Figure 10 The transverse chromatic aberration curve represents the chromatic aberration at different image heights on the imaging plane for the longest and shortest wavelengths. From Figure 10 As can be seen, the transverse chromatic aberration between the longest and shortest wavelengths is controlled within ±1.0 micrometers, indicating that the optical lens 200 can effectively correct aberrations in the edge field of view and the secondary spectrum of the entire image plane.

[0101] Third Embodiment

[0102] Please see Figure 11 The figure shows a schematic diagram of the structure of the optical lens 300 provided in the third embodiment of the present invention. The optical lens 300 provided in this embodiment has a structure that is generally the same as that of the optical lens 100 provided in the first embodiment. The main difference is that the image side S2 of the first lens is convex, the object side S3 of the second lens is concave, the fourth lens L4 has positive optical power, and the curvature radius, lens thickness, material selection and shape of the third lens of each lens are different.

[0103] The relevant parameters of each lens element in the optical lens 300 provided in this embodiment are shown in Table 5.

[0104] Table 5

[0105]

[0106]

[0107] In this embodiment, the aspherical parameters of each lens in the optical lens 300 are shown in Table 6.

[0108] Table 6

[0109]

[0110] Please refer to Figure 12 , Figure 13 , Figure 14 and Figure 15 The figures shown are the field curvature curve, distortion curve, axial chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 300.

[0111] Figure 12 The field curvature curve represents the degree of curvature of the meridional and sagittal image planes. From Figure 12 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.05mm, indicating that the field curvature correction of the optical lens 300 is good.

[0112] Figure 13 The distortion curve represents the distortion at different image heights on the imaging plane. From Figure 13 As can be seen, the distortion at different image heights on the imaging plane is controlled within ±0.6%, indicating that the distortion of the optical lens 300 is well corrected.

[0113] Figure 14 The axial chromatic aberration curve represents the aberrations along the optical axis at the imaging plane. From Figure 14 As can be seen, the axial chromatic aberration offset is controlled within ±0.02mm, indicating that the axial chromatic aberration of the optical lens 300 is well corrected.

[0114] Figure 15 The transverse chromatic aberration curve represents the chromatic aberration at different image heights on the imaging plane for the longest and shortest wavelengths. From Figure 15 As can be seen, the transverse chromatic aberration between the longest and shortest wavelengths is controlled within ±1.5 micrometers, indicating that the optical lens 300 can effectively correct aberrations at the edge of the field of view and the secondary spectrum of the entire image plane.

[0115] Table 7 shows the optical characteristics corresponding to the three embodiments above, mainly including the total optical length TTL of the optical lens, the effective focal length f, the maximum field of view 2θ, the image height IH corresponding to the maximum half field of view, the effective focal length of each lens, and the values ​​corresponding to each of the above conditions.

[0116] Table 7

[0117]

[0118]

[0119] In summary, the optical lens provided by this invention has at least the following advantages:

[0120] (1) Six aspherical lenses with specific optical power are used. Through the reasonable combination of specific surface shape and different optical power, the optical lens has a small total optical length and small distortion. It can well balance the total length of the lens and high pixel count, and meet the current demand of the mobile phone watch market for high-definition lenses.

[0121] (2) The lens in this optical lens has a large aperture and moderate thickness, making it easy to form and process, which can effectively reduce production costs.

[0122] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0123] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. An optical lens comprising six lenses, characterized in that, Along the optical axis from the object side to the imaging plane, the following are included in sequence: Aperture; A first lens having positive optical power, wherein the object side of the first lens is convex; A second lens with negative optical power, wherein the image-side surface of the second lens is concave; A third lens with negative optical power, wherein the object-side surface of the third lens is concave near the optical axis and the image-side surface of the third lens is convex near the optical axis; A fourth lens with optical power, wherein the object-side surface of the fourth lens is concave and the image-side surface of the fourth lens is convex; A fifth lens with negative optical power, wherein the object-side surface of the fifth lens is concave and the image-side surface of the fifth lens is convex; A sixth lens with negative optical power, wherein the object-side surface of the sixth lens is concave and the image-side surface of the sixth lens is convex; The total optical length of the optical lens satisfies: TTL < 4.0 mm.

2. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 0.55 < IH / TTL < 0.65; Wherein, IH represents the image height corresponding to the maximum half field of view of the optical lens, and TTL represents the total optical length of the optical lens.

3. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 4.2 mm / rad<IH / θ<4.6 mm / rad; Wherein, θ represents the maximum half field of view of the optical lens, and IH represents the image height corresponding to the maximum half field of view of the optical lens.

4. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 0 < (f1 + f2) / f3 < 0.2; Where f1 represents the effective focal length of the first lens, f2 represents the effective focal length of the second lens, and f3 represents the effective focal length of the third lens.

5. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 1.0 < R32 / R31 < 1.5; Wherein, R31 represents the radius of curvature of the object side of the third lens, and R32 represents the radius of curvature of the image side of the third lens.

6. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 9 < TTL / (CT3+AC34) < 11; Wherein, AC34 represents the air gap between the third lens and the fourth lens on the optical axis, CT3 represents the center thickness of the third lens, and TTL represents the total optical length of the optical lens.

7. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: -3.0 < f5 / f < -2.0; -5.5<(R51+R52) / (R51-R52)<-3.5; 14 < CT5 / AC56 < 17; Wherein, f5 represents the effective focal length of the fifth lens, f represents the effective focal length of the optical lens, R51 represents the radius of curvature of the object side of the fifth lens, R52 represents the radius of curvature of the image side of the fifth lens, CT5 represents the center thickness of the fifth lens, and AC56 represents the air gap between the fifth lens and the sixth lens on the optical axis.

8. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 0.5 < CT4 / AC45 < 0.7; 0 < (CT4 + AC45) / TTL < 0.5; Wherein, CT4 represents the center thickness of the fourth lens, AC45 represents the air gap between the fourth lens and the fifth lens on the optical axis, and TTL represents the total optical length of the optical lens.

9. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 0.9 < DM2 / DM3 < 1.0; Wherein, DM2 represents the optical effective diameter of the second lens, and DM3 represents the optical effective diameter of the third lens.

10. The optical lens according to claim 1, characterized in that, The optical lens satisfies the following condition: 4.5 < TTL / BFL < 5.5; Wherein, TTL represents the total optical length of the optical lens, and BFL represents the back focal length of the optical lens; 3.98mm ≤ TTL < 4.0 mm; Wherein, TTL represents the total optical length of the optical lens.

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