A glass-plastic hybrid optical system and a camera module using the same

Abstract

The present invention provides a glass-plastic hybrid optical system and a camera module applied thereto, which is composed of 8 lenses. By selecting 1 spherical glass lens, 1 aspherical glass lens and 6 plastic aspherical lenses, and rationally configuring the refractive power and surface shape of each lens, the optical lens can have a large field of view angle while combining the characteristics of miniaturization, low cost and large aperture. At the same time, it can also better capture the detailed information of the object, improve the optical lens's ability to capture the details of the photographed object, improve the image quality of the optical lens, and improve the resolution and imaging clarity of the optical lens, so as to meet people's requirements for wide-angle and high-quality imaging of sports cameras.

Description

Technical Field

[0001] The present application relates to the field of optical imaging, and in particular to a glass-plastic hybrid optical system and a camera module using the same. Background Art

[0002] With the continuous advancement of science and technology and the continuous improvement of people's living standards, it is becoming increasingly popular for people to capture the wonderful moments of outdoor activities such as cycling and off-roading through photography and share them on social media. In terms of videography, action cameras require a wider field of view, increased light throughput, and higher image quality. At the same time, market demand for smaller lenses is increasing. However, reducing lens size significantly impacts image quality, especially for wide-angle lenses with a large field of view. Therefore, there is a need for high-quality imaging lenses that combine a wide field of view with a compact design. Summary of the Invention

[0003] The present application aims to provide a glass-plastic hybrid optical system that has a large field of view angle range while being miniaturized, low-cost and having a large aperture. At the same time, it can also better capture the detailed information of the object, improve the ability of the optical lens to capture the details of the photographed object, improve the image quality of the optical lens, and improve the resolution and imaging clarity of the optical lens to meet people's requirements for wide-angle and high-quality imaging of sports cameras.

[0004] A glass-plastic hybrid optical system, comprising, along the optical axis, from the object plane to the image plane, a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens. The first lens is a spherical glass lens, the third lens is a glass aspherical lens, and the second lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are plastic aspherical lenses, all separated by air.

[0005] The first lens has negative optical power, its object side surface is convex, and its image side surface is concave;

[0006] The second lens has positive refractive power and its image side surface is convex;

[0007] The third lens has positive refractive power, its object-side surface is convex, and its image-side surface is convex;

[0008] The fourth lens has positive refractive power and its image side surface is convex;

[0009] The fifth lens has negative optical power and its image side surface is concave;

[0010] The sixth lens has optical power, its object-side surface is convex, and its image-side surface is concave;

[0011] The seventh lens has positive refractive power and its object side surface is convex;

[0012] The eighth lens has a negative optical power, its object side is convex, and its image side is concave.

[0013] Preferably, the optical system satisfies the following relationship: f / EPD ≤ 2.8; where f is the effective focal length of the optical imaging system, and EPD is the entrance pupil diameter of the optical imaging lens.

[0014] Preferably, the optical system satisfies the following relationship: 26mm < TTL*DT11 / f < 30mm; where TTL is the on-axis distance from the object side of the first lens to the imaging surface, DT11 is the maximum effective radius of the object side of the first lens, and f is the effective focal length of the optical imaging system.

[0015] Preferably, the optical system satisfies the following relationship: 110° / mm < 2*HFOV / EPD < 130° / mm; where HFOV is half of the maximum field angle of the optical system, and EPD is the entrance pupil diameter of the optical system.

[0016] Preferably, the optical system satisfies the following relationship:

[0017] -14mm < f1*f4 / f < -12.9mm;

[0018] -6.1 ≤ f45 / f < -5.4;

[0019] 5.0 < f12 / f23 < 6.8;

[0020] 1.5 < f678 / (f123 + f456) ≤ 2.3;

[0021] -6.7 < f78 / (CT7 + 10*CT8) < -3.9;

[0022] Where f1 is the effective focal length of the first lens, f4 is the effective focal length of the fourth lens, f12 is the effective combined focal length of the first lens and the second lens, f23 is the effective combined focal length of the second lens and the third lens, f45 is the effective combined focal length of the fourth lens and the fifth lens, f78 is the effective combined focal length of the seventh lens and the eighth lens, f123 is the effective combined focal length of the first lens, the second lens and the third lens, f456 is the effective combined focal length of the fourth lens, the fifth lens and the sixth lens, f678 is the effective combined focal length of the sixth lens, the seventh lens and the eighth lens, f is the effective focal length of the optical imaging system, CT7 is the central thickness of the seventh lens on the optical axis, and CT8 is the central thickness of the eighth lens on the optical axis.

[0023] Preferably, the optical system satisfies the following relationship:

[0024] 6.0 ≤ (R1 + R2) / R2 < 7.0;

[0025] 2.2<|R15+R16 / (SAG15+SAG16)|<4.2;

[0026] Among them, R1 is the curvature radius of the object side of the first lens, R2 is the curvature radius of the image side of the first lens, R15 is the curvature radius of the object side of the eighth lens, R16 is the curvature radius of the image side of the eighth lens, SAG15 is the distance from the maximum effective aperture of the object side of the eighth lens to the intersection of the object side of the eighth lens and the optical axis in the direction parallel to the optical axis, and SAG16 is the distance from the maximum effective aperture of the image side of the eighth lens to the intersection of the image side of the eighth lens and the optical axis in the direction parallel to the optical axis.

[0027] Preferably, the optical system satisfies the following relationship:

[0028] -3.0 <DT52-DT51 / (SAG11+SAG10)<-2.0;

[0029] 4.9 ≤ (DT62-DT61) / |DT12-DT11|<6.9;

[0030] Among them, DT11 is the maximum effective radius of the objective side of the first lens, DT12 is the maximum effective radius of the image side of the first lens, DT51 is the maximum effective radius of the objective side of the fifth lens, DT52 is the maximum effective radius of the image side of the fifth lens, DT61 is the maximum effective radius of the objective side of the sixth lens, DT62 is the maximum effective radius of the image side of the sixth lens, SAG10 is the distance from the maximum effective aperture of the objective side of the fifth lens to the intersection of the objective side of the fifth lens and the optical axis in the direction parallel to the optical axis, and SAG11 is the distance from the maximum effective aperture of the image side of the fifth lens to the intersection of the image side of the fifth lens and the optical axis in the direction parallel to the optical axis.

[0031] Preferably, the maximum effective radius of the objective side of the first lens is ≤6.0 mm.

[0032] Preferably, the aperture of the optical system is located between the third lens and the third lens.

[0033] Preferably, the F number of the optical system is 2.8, the full field angle is greater than 157°, and the total length of the lens is ≤16.75 mm.

[0034] On the other hand, an embodiment of the present application also provides a camera module, which includes at least an optical lens, and the above-mentioned glass-plastic hybrid optical system is installed in the optical lens.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] The present invention provides a glass-plastic hybrid optical system and a camera module applied thereto, which is composed of 8 lenses. By selecting 1 spherical glass lens, 1 aspherical glass lens and 6 plastic aspherical lenses, and rationally configuring the refractive power and surface shape of each lens, the optical lens can have a large field of view angle while combining the characteristics of miniaturization, low cost and large aperture. At the same time, it can also better capture the detailed information of the object, improve the optical lens's ability to capture the details of the photographed object, improve the image quality of the optical lens, and improve the resolution and imaging clarity of the optical lens, so as to meet people's requirements for wide-angle and high-quality imaging of sports cameras. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments.

[0038] Figure 1 Schematic diagram of the structure of the optical system or camera module of Example 1 of the present application;

[0039] Figure 2 axial chromatic aberration, astigmatism, and distortion curves of the optical imaging lens of the optical system or camera module in Example 1 of the present application;

[0040] Figure 3 2 is a schematic structural diagram of an optical system or camera module according to embodiment 2 of the present application;

[0041] Figure 4 axial chromatic aberration, astigmatism, and distortion curves of the optical imaging lens of the optical system or camera module of Example 2 of the present application;

[0042] Figure 5 2 is a schematic structural diagram of the optical system or camera module according to Embodiment 3 of the present application;

[0043] Figure 6 axial chromatic aberration, astigmatism, and distortion curves of the optical imaging lens of the optical system or camera module of Example 3 of the present application;

[0044] Figure 7 Schematic diagram of the structure of the optical system or camera module according to Example 4 of the present application;

[0045] Figure 8 These are the on-axis chromatic aberration, astigmatism, and distortion curves of the optical imaging lens of the optical system or camera module of Example 4 of the present application. DETAILED DESCRIPTION

[0046] like Figure 1-8As shown, the present application provides a glass-plastic hybrid optical system, comprising a protective glass EO, a first lens E1, a second lens E2, a third lens E3, an aperture STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8, and an infrared filter E9, which are arranged in sequence from the object side. The first lens E1 is a spherical glass lens, the third lens E3 is a glass aspherical lens, the second lens E2, the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7 and the eighth lens E8 are plastic aspherical lenses, and are separated and arranged with air as the spacer; the first lens E1 has a negative optical power, its object side surface is convex, and its image side surface is concave; The second lens E2 has positive focal power, and its image side surface is convex; the third lens E3 has positive focal power, its object side surface is convex, and its image side surface is convex; the fourth lens E4 has positive focal power, and its image side surface is convex; the fifth lens E5 has negative focal power, and its image side surface is concave; the sixth lens E6 has focal power, its object side surface is convex, and its image side surface is concave; the seventh lens E7 has positive focal power, and its object side surface is convex; the eighth lens E8 has negative focal power, its object side surface is convex, and its image side surface is concave; the maximum effective radius of the object side surface of the first lens E1 is ≤6.0mm; the F number of the glass-plastic hybrid optical system and the camera module used therein is 2.8.

[0047] The optical system of the embodiment of the present application is composed of 8 lenses. By selecting 1 spherical glass lens, 1 aspherical glass lens and 6 plastic aspherical lenses, and rationally configuring the refractive power and surface shape of each lens, the optical lens can have a wide field of view while combining the characteristics of miniaturization, low cost and large aperture. At the same time, it can also better capture object detail information, improve the optical lens's ability to capture details of the photographed object, improve the image quality of the optical lens, and improve the resolution and imaging clarity of the optical lens to meet people's requirements for wide-angle and high-quality imaging of sports cameras.

[0048] Furthermore, the optical system satisfies the following relationships: f / EPD ≤ 2.8, 26mm < TTL*DT11 / f < 30mm, where TTL is the on-axis distance from the object side of the first lens E1 to the imaging surface, DT11 is the maximum effective radius of the object side of the first lens E1, f is the effective focal length of the optical imaging system, and EPD is the entrance pupil diameter of the optical imaging lens. When the above relationships are satisfied, the optical imaging system has the characteristics of a large aperture while meeting the wide-angle requirement, which is beneficial to the miniaturization and thinness of the optical lens. When the optical lens is applied to a camera module, it can be adapted to the large-size chip of the camera module, thereby being beneficial to improving the image plane brightness of the optical lens. When below the lower limit of the relationship, the field angle of the optical lens becomes smaller, and it is difficult to achieve the wide-angle effect of the optical lens; when exceeding the upper limit of the relationship, the overall length of the optical lens becomes longer, and the aperture of the first lens becomes larger, which is not conducive to the miniaturization and thinness of the optical lens.

[0049] Furthermore, the optical system satisfies the following relationship: 110° / mm < 2*HFOV / EPD < 130° / mm; where HFOV is half of the maximum field angle of the optical system, and EPD is the entrance pupil diameter of the optical system. By reasonably controlling the range of the above sub-formula, the light input amount and the field range of the optical lens can be controlled, so that the optical lens can have a large field angle, enabling the optical lens to have a wider imaging ability. At the same time, the optical lens can also have the effect of a large aperture and a longer depth of field range, that is, it can achieve clear imaging at infinity and large angles. For nearby scenes, the optical lens can still have a clear recognition ability, so as to ensure that the optical lens has a good effect on capturing various details of both distant and nearby scenes. When exceeding the upper limit of the above relationship, the field angle of the optical lens is too large, and the entrance pupil diameter is too small, which is likely to cause excessive off-axis field distortion, resulting in distortion and vignetting phenomena in the outer periphery of the image, and the imaging performance of the optical lens is reduced; when below the lower limit of the above relationship, it is not conducive to meeting the field angle range of the optical lens, and insufficient object space information can be obtained, unable to meet the design requirements of large-angle shooting.

[0050] Further, the optical system satisfies the following relationship: -14 mm < f1 * f4 / f < -12.9 mm, where f1 is the effective focal length of the first lens E1, f4 is the effective focal length of the fourth lens E4, and f is the effective focal length of the optical imaging system. Effect: By reasonably controlling the ratio range of the effective focal lengths of the first lens E1, the fourth lens E4, and the optical imaging system, the optical system can satisfy a large field angle while achieving high imaging resolution. Exceeding the upper limit of the relationship, the refractive power of the first lens E1 and the fourth lens E4 is insufficient, and it is difficult for large-angle light rays to enter the optical system, which is not conducive to expanding the field angle range of the optical system. Below the lower limit of the relationship, the refractive power of the first lens E1 and the fourth lens E4 is too strong, and strong astigmatism and chromatic aberration are easily generated, which is not conducive to high-resolution imaging characteristics.

[0051] Further, the optical system satisfies the following relationship: -6.1 ≤ f45 / f < -5.4, where f45 is the effective combined focal length of the fourth lens E4 and the fifth lens E5, and f is the effective focal length of the optical imaging system. The fourth lens E4 provides positive refractive power for the optical system, and the fifth lens E5 provides negative refractive power for the optical system. By using a structure with two lenses having positive and negative refractive powers in combination, it is beneficial for the mutual correction of aberrations. Below the lower limit of the relationship, the refractive power of the lens group is too small, and large marginal aberrations and chromatic aberration are easily generated, which is not conducive to improving the resolution performance. Exceeding the upper limit of the relationship, the overall refractive power of the fourth lens E4 and the fifth lens E5 is too strong, making the lens group prone to serious astigmatism, which is not conducive to improving the imaging quality.

[0052] Further, the optical system satisfies the following relationship: 5.0 < f12 / f23 < 6.8, where f12 is the effective combined focal length of the first lens E1 and the second lens E2, and f23 is the effective combined focal length of the second lens E2 and the third lens E3. By restricting the ratio of the combined focal lengths of the first lens E1, the second lens E2 and the combined focal lengths of the second lens E2, the third lens E3, the optical power from the first lens E1 to the third lens E3 can be reasonably distributed, effectively restricting the aberration change from the central field to the marginal field of the optical system, while avoiding excessive bending of the effective diameter area from the first lens E1 to the third lens E3, deteriorating the imaging performance of the optical system, and suppressing the sensitivity of lens eccentricity and tilt within a good range.

[0053] Furthermore, the optical system satisfies the following relationship: 1.5 < f678 / (f123 + f456) ≤ 2.3, where f123 is the effective combined focal length of the first lens E1, the second lens E2, and the third lens E3, f456 is the effective combined focal length of the fourth lens E4, the fifth lens E5, and the sixth lens E6, and f678 is the effective combined focal length of the sixth lens E6, the seventh lens E7, and the eighth lens E8. By defining the range of the above relational expression, the front lens group (the first lens E1, the second lens E2, and the third lens E3) of the optical system provides positive refractive power, which is beneficial for large-angle light beams to pass through and enter, so as to achieve the wide-angle design of the optical system, and is also beneficial for improving the brightness of the imaging surface of the optical system; while the rear lens group (the sixth lens E6, the seventh lens E7, and the eighth lens E8) of the optical system provides negative refractive power. On the one hand, it is beneficial for controlling the height of the light rays emitted by the optical system to reduce the high-order aberrations of the optical system and the outer diameters of each lens in the rear lens group; on the other hand, it can correct the field curvature generated by the front lens group to reduce the influence on the resolution of the optical system and improve the imaging quality of the optical system.

[0054] Furthermore, the optical system satisfies the following relationship: -6.7 < f78 / (CT7 + 10 * CT8) < -3.9, where f78 is the effective combined focal length of the seventh lens E7 and the eighth lens E8, CT7 is the central thickness of the seventh lens E7 on the optical axis, and CT8 is the central thickness of the eighth lens E8 on the optical axis. By reasonably allocating the ratio relationship between the combined focal length and the central thickness of the seventh lens E7 and the eighth lens E8, the refractive powers of the two lenses with one positive and one negative can also be reasonably matched, which is beneficial for correcting aberrations and thus beneficial for improving the imaging quality of the optical system. Therefore, by satisfying the above relational expression, it is possible to avoid too large a difference in the central thickness between the seventh lens E7 and the eighth lens E8, and at the same time, it is also possible to avoid too large a difference in the thermal deformation amounts generated by the seventh lens E7 and the eighth lens E8 in an environment with a large change in high and low temperature environments, which is beneficial for reducing the risk of poor reliability of the lens under high or low temperature conditions.

[0055] Furthermore, the optical system satisfies the following relationship: 6.0 ≤ (R1 + R2) / R2 < 7.0, where R1 is the curvature radius of the object side of the first lens E1, and R2 is the curvature radius of the image side of the first lens E1. By controlling the curvature radii of the object side and the image side of the first lens E1, it is possible to reasonably control the total deflection angle of the object side and the image side of the first lens E1 at the edge field of view within a reasonable range, and effectively reduce the sensitivity of the system.

[0056] Furthermore, the optical system satisfies the following relationship: 2.2 < |R15 + R16 / (SAG15 + SAG16)| < 4.2, where R15 is the radius of curvature of the object side surface of the eighth lens E8, R16 is the radius of curvature of the image side surface of the eighth lens E8, SAG15 is the distance parallel to the optical axis from the maximum effective clear aperture of the object side surface of the eighth lens E8 to the intersection of the object side surface of the eighth lens E8 and the optical axis, and SAG16 is the distance parallel to the optical axis from the maximum effective clear aperture of the image side surface of the eighth lens E8 to the intersection of the image side surface of the eighth lens E8 and the optical axis. By making the optical system satisfy the above relational expression, the ratio relationship between the radius of curvature at the optical axis of the object side surface and the image side surface of the eighth lens E8 and the sagitta at the maximum effective aperture can be controlled, providing a negative refractive power for the optical system, so that large-angle light rays can be incident on the optical system, expanding the field angle range of the optical system. When the ratio is higher than the upper limit of the relational expression, the bending force of the eighth lens E8 is too strong, and the imaging of the image plane is more sensitive to the change of the eighth lens E8, resulting in larger aberrations. When the ratio is lower than the lower limit of the relational expression, the sagitta at the maximum effective aperture of the object side surface of the eighth lens E8 is too large, and the eighth lens E8 is too curved, which is likely to generate ghost images and increase the risk of ghost images.

[0057] Furthermore, the optical system satisfies the following relationship: -3.0 < DT52 - DT51 / (SAG11 + SAG10) < -2.0, where DT51 is the maximum effective radius of the object side surface of the fifth lens E5, DT52 is the maximum effective radius of the image side surface of the fifth lens E5, SAG10 is the distance parallel to the optical axis from the maximum effective clear aperture of the object side surface of the fifth lens E5 to the intersection of the object side surface of the fifth lens E5 and the optical axis, and SAG11 is the distance parallel to the optical axis from the maximum effective clear aperture of the image side surface of the fifth lens E5 to the intersection of the image side surface of the fifth lens E5 and the optical axis. By limiting the range of the above embodiments, on the one hand, it can prevent the object side surface of the fifth lens E5 from being too curved, reducing the processing difficulty of the fifth lens E5, preventing uneven coating due to the excessive curvature of the fifth lens E5, and at the same time facilitating the incidence of large-angle light rays on the optical system, thereby improving the imaging quality of the optical system; on the other hand, it avoids the object side surface of the fifth lens E5 from being too flat, reducing the risk of generating ghost images. When it is higher than the upper limit of the relational expression, the optical effective aperture of the object side surface of the fifth lens E5 is too large, and the deflection of the object side light rays is insufficient, which is likely to cause an increase in the optical effective aperture of the object side lens, further leading to an increase in the optical effective aperture of the object side surface of the first lens E1, which is not conducive to reducing the head aperture and thus not conducive to the assembly between the lenses in the optical system; when it is lower than the lower limit of the relational expression, the sagitta of the object side surface of the fifth lens E5 increases, and the fifth lens E5 is too curved, increasing the processing difficulty.

[0058] Furthermore, the optical system satisfies the following relationship: 4.9 ≤ (DT62-DT61) / |DT12-DT11|<6.9; wherein DT11 is the maximum effective radius of the object-side surface of the first lens E1, DT12 is the maximum effective radius of the image-side surface of the first lens E1, DT61 is the maximum effective radius of the object-side surface of the sixth lens E6, and DT62 is the maximum effective radius of the image-side surface of the sixth lens E6. By limiting the maximum effective radius of the object-side and image-side surfaces of the first lens E1 and the sixth lens E6 to a reasonable range, the size of the lenses can be reduced, miniaturization of the lenses can be achieved, and the resolution can be improved. If the upper limit of the relationship is exceeded, the aperture of the first lens E1 is excessively compressed, affecting the improvement of the system's imaging quality. If the lower limit is below the lower limit, the aperture of the first lens E1 is too large, resulting in a larger overall system size, which is not conducive to miniaturization of the imaging system.

[0059] Example 1

[0060] Specifically, as a preferred embodiment of the present invention but not limiting, the following reference is made to Figures 1 to 2 The optical imaging lens according to Example 1 of the present application is described. Figure 1 A schematic structural diagram of an optical imaging lens according to Example 1 of the present application is shown.

[0061] like Figure 1 As shown, the optical imaging lens according to an exemplary embodiment of the present application includes, in order from the object side to the image side along the optical axis: a cover glass E0, a first lens E1, a second lens E2, a third lens E3, an STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, an infrared filter E9, and an imaging surface S19.

[0062] The cover glass E0 has an object-side surface S1 and an image-side surface S2. The first lens E1 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The second lens E2 has positive focal power, with its object-side surface S5 being convex and its image-side surface S6 being convex. The third lens E3 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fourth lens E4 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The fifth lens E5 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The sixth lens E6 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The seventh lens E7 has positive focal power, with its object-side surface S15 being convex and its image-side surface S16 being convex. The eighth lens E8 has negative focal power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E9 has an object-side surface S19 and an image-side surface S20. Light from an object passes through the surfaces S1 to S20 in sequence and is finally imaged on the imaging surface S21.

[0063] Table 1 shows the surface type, curvature radius, thickness, and material of each lens of the optical imaging lens of Example 1, wherein the units of curvature radius and thickness are both millimeters (mm).

[0064] Table 1

[0065]

[0066] In Table 1, the object side and image side of any one of the second lens element E2, the third lens element E3, the fourth lens element E4, the fifth lens element E5, the sixth lens element E6, the seventh lens element E7, and the eighth lens element E8 are all Q-type aspherical surfaces. The surface shape of each aspherical lens element can be defined by, but is not limited to, the following aspherical surface formula:

[0067]

[0068] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the aspheric vertex, K is the cone coefficient, Am is the aspheric coefficient, r is the radius of the aspheric surface, and c is the curvature of the aspheric vertex. max is the maximum radial radius coordinate, u=r / r max Table 4 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of the aspheric surfaces that can be used in the first embodiment.

[0069] Table 2

[0070]

[0071] Figure 2 The following graphs show the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 1. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The optical imaging lens of Example 1 can achieve excellent imaging quality.

[0072] Example 2

[0073] Specifically, as a preferred embodiment of the present invention but not limiting, the following reference is made to Figures 3 and 4 The optical imaging lens according to Example 2 of the present application is described. Figure 3 A schematic structural diagram of an optical imaging lens according to Example 2 of the present application is shown.

[0074] like Figure 3As shown, the optical imaging lens according to an exemplary embodiment of the present application includes, in order from the object side to the image side along the optical axis: a cover glass E0, a first lens E1, a second lens E2, a third lens E3, an STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, an infrared filter E9, and an imaging surface S19.

[0075] The cover glass E0 has an object-side surface S1 and an image-side surface S2. The first lens E1 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The second lens E2 has positive focal power, with its object-side surface S5 being concave and its image-side surface S6 being convex. The third lens E3 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fourth lens E4 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The fifth lens E5 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The sixth lens E6 has negative focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The seventh lens E7 has positive focal power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The eighth lens E8 has negative focal power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E9 has an object-side surface S19 and an image-side surface S20. Light from an object passes through the surfaces S1 to S20 in sequence and is finally imaged on the imaging surface S21.

[0076] Table 3 shows the surface type, curvature radius, thickness, and material of each lens of the optical imaging lens system of Example 2, where the units of curvature radius and thickness are both millimeters (mm).

[0077] Table 3

[0078]

[0079] In Table 3, the object side and image side of any one of the second lens element E2, the third lens element E3, the fourth lens element E4, the fifth lens element E5, the sixth lens element E6, the seventh lens element E7, and the eighth lens element E8 are all Q-type aspherical surfaces. The surface shape of each aspherical lens element can be defined by, but is not limited to, the following aspherical surface formula:

[0080]

[0081] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the aspheric vertex, K is the cone coefficient, Am is the aspheric coefficient, r is the radius of the aspheric surface, and c is the curvature of the aspheric vertex. max is the maximum radial radius coordinate, u=r / r maxTable 4 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of the aspheric surfaces that can be used in the first embodiment.

[0082] Table 4

[0083]

[0084] Figure 4 The following graphs show the axial chromatic aberration, astigmatism, and distortion curves for the optical imaging lens of Example 2. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The optical imaging lens of Example 2 achieves excellent imaging quality.

[0085] Example 3:

[0086] Specifically, as a preferred embodiment of the present invention but not limiting, the following reference is made to Figures 5 and 6 The optical imaging lens according to Example 3 of the present application is described. Figure 5 A schematic structural diagram of an optical imaging lens according to Example 3 of the present application is shown.

[0087] like Figure 5 As shown, the optical imaging lens according to an exemplary embodiment of the present application includes, in order from the object side to the image side along the optical axis: a cover glass E0, a first lens E1, a second lens E2, a third lens E3, an STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, an infrared filter E9, and an imaging surface S19.

[0088] The cover glass E0 has an object-side surface S1 and an image-side surface S2. The first lens E1 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The second lens E2 has positive focal power, with its object-side surface S5 being concave and its image-side surface S6 being convex. The third lens E3 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fourth lens E4 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The fifth lens E5 has negative focal power, with its object-side surface S11 being concave and its image-side surface S12 being concave. The sixth lens E6 has negative focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The seventh lens E7 has positive focal power, with its object-side surface S15 being convex and its image-side surface S16 being convex. The eighth lens E8 has negative focal power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E9 has an object-side surface S19 and an image-side surface S20. Light from an object passes through the surfaces S1 to S20 in sequence and is finally imaged on the imaging surface S21.

[0089] Table 5 shows the surface type, curvature radius, thickness, and material of each lens of the optical imaging lens system of Example 3, where the units of curvature radius and thickness are both millimeters (mm).

[0090] Table 5

[0091]

[0092] In Table 5, the object side and image side of any one of the second lens element E2, the third lens element E3, the fourth lens element E4, the fifth lens element E5, the sixth lens element E6, the seventh lens element E7, and the eighth lens element E8 are all Q-type aspherical surfaces. The surface shape of each aspherical lens can be defined by, but is not limited to, the following aspherical surface formula:

[0093]

[0094] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the aspheric vertex, K is the cone coefficient, Am is the aspheric coefficient, r is the radius of the aspheric surface, and c is the curvature of the aspheric vertex. max is the maximum radial radius coordinate, u=r / r max Table 4 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of the aspheric surfaces that can be used in the first embodiment.

[0095] Table 6

[0096]

[0097] Figure 6 The following plots show the axial chromatic aberration, astigmatism, and distortion of the optical imaging lens of Example 3. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The optical imaging lens of Example 3 achieves excellent imaging quality.

[0098] Example 4:

[0099] Specifically, as a preferred embodiment of the present invention but not limiting, the following reference is made to Figures 7 and 8 An optical imaging lens according to Example 4 of the present application is described. Figure 7 A schematic structural diagram of an optical imaging lens according to Example 4 of the present application is shown.

[0100] like Figure 7As shown, the optical imaging lens according to an exemplary embodiment of the present application includes, in order from the object side to the image side along the optical axis: a cover glass E0, a first lens E1, a second lens E2, a third lens E3, an STO, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, an infrared filter E9, and an imaging surface S19.

[0101] The cover glass E0 has an object-side surface S1 and an image-side surface S2. The first lens E1 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The second lens E2 has positive focal power, with its object-side surface S5 being concave and its image-side surface S6 being convex. The third lens E3 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fourth lens E4 has positive focal power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The fifth lens E5 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The sixth lens E6 has negative focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The seventh lens E7 has positive focal power, with its object-side surface S15 being convex and its image-side surface S16 being convex. The eighth lens E8 has negative focal power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E9 has an object-side surface S19 and an image-side surface S20. Light from an object passes through the surfaces S1 to S20 in sequence and is finally imaged on the imaging surface S21.

[0102] Table 7 shows the surface type, curvature radius, thickness, and material of each lens of the optical imaging lens system of Example 4, where the units of curvature radius and thickness are both millimeters (mm).

[0103] Table 7

[0104]

[0105] In Table 7, any one of the object side and image side surfaces of the second lens element E2, the third lens element E3, the fourth lens element E4, the fifth lens element E5, the sixth lens element E6, the seventh lens element E7, and the eighth lens element E8 is a Q-type aspherical surface. The surface shape of each aspherical lens can be defined by, but is not limited to, the following aspherical surface formula:

[0106]

[0107] Where Z is the distance from the corresponding point on the aspheric surface to the plane tangent to the vertex of the surface, r is the radial coordinate of the aspheric surface, c is the curvature of the aspheric vertex, K is the cone coefficient, Am is the aspheric coefficient, r is the radius of the aspheric surface, and c is the curvature of the aspheric vertex. max is the maximum radial radius coordinate, u=r / r maxTable 4 shows the conic coefficients and higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 of the aspheric surfaces that can be used in the first embodiment.

[0108] Table 8

[0109]

[0110] Figure 8 The following plots show the axial chromatic aberration, astigmatism, and distortion of the optical imaging lens of Example 4. Axial chromatic aberration indicates the deviation of light of different wavelengths from the focal point after passing through the lens; astigmatism represents meridional and sagittal image curvature; and distortion indicates the magnitude of distortion at different image heights. The optical imaging lens of Example 4 achieves excellent imaging quality.

[0111] In Examples 1-4, the basic data are as follows:

[0112] Table 9

[0113]

[0114] In Examples 1-4, each conditional expression satisfies the conditions in the following table:

[0115] Table 10

[0116]

[0117] A camera module includes at least an optical lens, in which the above-mentioned glass-plastic hybrid optical system is installed. The glass-plastic hybrid optical system configured in the present invention has the characteristics of miniaturization, low cost and large aperture while having a large field of view angle range. It has a compact structure and is easy to process and install. At the same time, the configuration of the large aperture can increase the amount of light entering the optical system and higher imaging quality.

[0118] The above descriptions are provided in conjunction with specific content to provide one or more embodiments, and the specific implementation of the present invention is not limited to these descriptions. Any similarity or similarity with the methods, structures, etc. of the present invention, or any technical deduction or substitution based on the concept of the present invention, shall be considered within the scope of protection of the present invention.

Claims

1. A glass-plastic hybrid optical system, characterized by: The optical system comprises a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens in order from the object plane to the image plane. The first lens is a spherical glass lens, the third lens is a glass aspherical lens, and the second lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are plastic aspherical lenses, and are separated by air. The first lens has negative optical power, its object side surface is convex, and its image side surface is concave; The second lens has positive refractive power and its image side surface is convex; The third lens has positive refractive power, its object-side surface is convex, and its image-side surface is convex; The fourth lens has positive refractive power and its image side surface is convex; The fifth lens has negative optical power and its image side surface is concave; The sixth lens has optical power, its object-side surface is convex, and its image-side surface is concave; The seventh lens has positive refractive power, and its object side surface is convex; The eighth lens has negative optical power, its object-side surface is convex, and its image-side surface is concave; The full field of view of the optical system is greater than 157°; The optical system satisfies the following relationships: 2.79 ≤ f / EPD ≤ 2.8, 26mm < TTL*DT11 / f < 30mm; Wherein, TTL is the on-axis distance from the object side of the first lens to the imaging surface, DT11 is the maximum effective radius of the object side of the first lens, f is the effective focal length of the optical system, and EPD is the entrance pupil diameter of the optical system.

2. The glass-plastic hybrid optical system according to claim 1, wherein: The optical system satisfies the following relationship: 110° / mm < 2*HFOV / EPD < 130° / mm; Among them, HFOV is half of the maximum field of view of the optical system, and EPD is the entrance pupil diameter of the optical system.

3. The glass-plastic hybrid optical system according to claim 1, wherein: The optical system satisfies the following relationship: -14mm < f1*f4 / f < -12.9mm; -6.1≤ f45 / f<-5.4; Wherein, f1 is the effective focal length of the first lens, f4 is the effective focal length of the fourth lens, f45 is the effective combined focal length of the fourth and fifth lenses, and f is the effective focal length of the optical system.

4. The glass-plastic hybrid optical system according to claim 1, wherein: The optical system satisfies the following relationship: 5.0 < f12 / f23 < 6.8; 1.5 < f678 / (f123+f456) ≤ 2.3; Among them, f12 is the effective combined focal length of the first and second lenses, f23 is the effective combined focal length of the second and third lenses, f123 is the effective combined focal length of the first, second and third lenses, f456 is the effective combined focal length of the fourth, fifth and sixth lenses, and f678 is the effective combined focal length of the sixth, seventh and eighth lenses.

5. The glass-plastic hybrid optical system according to claim 1, wherein: The optical system satisfies the following relationship: -6.7 < f78 / (CT7+10*CT8) <-3.9; Wherein, f78 is the effective combined focal length of the seventh lens and the eighth lens, CT7 is the center thickness of the seventh lens on the optical axis, and CT8 is the center thickness of the eighth lens on the optical axis.

6. The glass-plastic hybrid optical system according to claim 1, wherein: The optical system satisfies the following relationship: 6.0 ≤ (R1+R2) / R2 < 7.0; 2.2 < |R15+R16 / (SAG15+SAG16)| < 4.2; Among them, R1 is the curvature radius of the object side of the first lens, R2 is the curvature radius of the image side of the first lens, R15 is the curvature radius of the object side of the eighth lens, R16 is the curvature radius of the image side of the eighth lens, SAG15 is the distance from the maximum effective aperture of the object side of the eighth lens to the intersection of the object side of the eighth lens and the optical axis in the direction parallel to the optical axis, and SAG16 is the distance from the maximum effective aperture of the image side of the eighth lens to the intersection of the image side of the eighth lens and the optical axis in the direction parallel to the optical axis.

7. The glass-plastic hybrid optical system according to claim 1, characterized in that: The optical system satisfies the following relationship: -3.0 < DT52-DT51 / (SAG11+SAG10) < -2.0; 4.9 ≤ (DT62-DT61) / |DT12-DT11| < 6.9; Among them, DT11 is the maximum effective radius of the objective side of the first lens, DT12 is the maximum effective radius of the image side of the first lens, DT51 is the maximum effective radius of the objective side of the fifth lens, DT52 is the maximum effective radius of the image side of the fifth lens, DT61 is the maximum effective radius of the objective side of the sixth lens, DT62 is the maximum effective radius of the image side of the sixth lens, SAG10 is the distance from the maximum effective aperture of the objective side of the fifth lens to the intersection of the objective side of the fifth lens and the optical axis in the direction parallel to the optical axis, and SAG11 is the distance from the maximum effective aperture of the image side of the fifth lens to the intersection of the image side of the fifth lens and the optical axis in the direction parallel to the optical axis.

8. The glass-plastic hybrid optical system according to claim 1, wherein: The maximum effective radius of the object side of the first lens is ≤6.0mm; The aperture stop of this optical system is located between the third lens and the third lens.

9. The glass-plastic hybrid optical system according to claim 1, wherein: The F number of this optical system is 2.8, and the total lens length is ≤16.75 mm.

10. A camera module, comprising at least an optical lens, characterized in that: The optical lens is equipped with the glass-plastic hybrid optical system described in any one of claims 1 to 9.

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