Intrafocal wide-angle photographic lens and image pickup device

Abstract

The application is suitable for the field of photographic technology, and provides an inner focus wide-angle photographic lens and an image pickup device, which comprises, from an object side to an image side, a first lens group with negative focal length, a second lens group with positive focal length, an aperture diaphragm, a third lens group with negative focal length, and a fourth lens group with positive focal length; during the process of focusing from infinity to a close distance, the third lens group moves along the optical axis to the image side direction, and the first lens group, the second lens group and the fourth lens group remain unchanged relative to the image plane position; the inner focus wide-angle photographic lens satisfies the following conditional expressions: 1.0 <= F2 / F <= 2.0, (1); 1.0 <= F3 / F1 <= 3.0, (2); 0.7 <= F / BF <= 3.0, (3); the application effectively controls the size of the lens by reasonably designing the focal length range and the moving mode of the lens group, and simultaneously realizes the characteristics of high resolution, low dispersion and fast focusing while reducing the cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of photography technology, and particularly relates to an inner focus type wide-angle photographic lens and a camera device. BACKGROUND

[0002] In recent years, micro single cameras have achieved rapid expansion of demand in the photography market due to their small and light body advantages and increasingly advanced imaging performance. Compared with traditional single-lens reflex cameras, which have the shortcoming of being bulky and inconvenient to carry, micro single cameras not only meet the portable needs of professional photographers for outdoor fieldwork and mobile creation, but also achieve a leap in resolution and image quality as high-precision CMOS chip technology continues to mature, becoming the mainstream choice that balances professional creation and daily recording.

[0003] However, in the field of interchangeable lenses that are matched with micro single cameras, especially wide-angle lenses with large apertures, there are still industry pain points that are difficult to balance "performance, size, and cost". On the one hand, wide-angle lenses need to meet the light intake demand brought by large apertures to adapt to shooting scenes in low-light environments, while also needing to ensure the open field of view and spatial expression unique to wide-angle focal lengths. On the other hand, existing products often use complex optical structure designs to pursue higher imaging quality and suppress the distortion and dark corner problems that are prone to occur in wide-angle lenses, resulting in larger lens size, excessive weight, and a contradiction with the "portable gene" of micro single cameras. This also pushes up manufacturing costs, leaving consumers with the dilemma of "expensive high-performance lenses and compromised image quality of affordable lenses". In addition, some products, even if the size is controlled, still have the problem of insufficient sharpness, especially in the edge area of the image, and the detail resolution cannot meet the high-resolution requirements of professional creation.

[0004] Currently, the same type of lens products on the market generally have the problems of large size, slightly long focal length, and insufficient field of view. Some products use a design scheme of three aspherical lenses to optimize optical performance, but this leads to rising costs, and still has deficiencies in aperture size, distortion control, and other aspects, affecting the imaging quality, and the overall imaging sharpness also needs to be strengthened. SUMMARY

[0005] The purpose of the present application is to provide an inner focus type wide-angle photographic lens and a camera device, aiming to solve the problems of existing wide-angle lenses, such as large size, uneven imaging, high cost, and slow focusing.

[0006] In a first aspect, the present application provides an internal focusing wide-angle photographic lens, which comprises, in order from the object side to the image side, a first lens group with negative focal power, a second lens group with positive focal power, an aperture stop, a third lens group with negative focal power, and a fourth lens group with positive focal power, wherein during the internal focusing from infinity to close range, the third lens group moves along the optical axis towards the image side, and the first lens group, the second lens group and the fourth lens group remain unchanged relative to the image plane position.

[0007] The internal focusing wide-angle photographic lens satisfies the following conditional expressions:

[0008] 1.0≤F2 / F≤2.0, (1)

[0009] 1.0≤F3 / F1≤3.0, (2)

[0010] 0.7≤F / BF≤3.0, (3)

[0011] D / TTL≤0.5, (4)

[0012] wherein F1 represents the focal length of the first lens group, F2 represents the focal length of the second lens group, F3 represents the focal length of the third lens group, F represents the focal length of the internal focusing wide-angle photographic lens, BF represents the distance from the lens surface closest to the image plane to the image plane, D represents the maximum image plane diameter of the internal focusing wide-angle photographic lens, and TTL represents the total optical length of the internal focusing wide-angle photographic lens.

[0013] In some embodiments, the first lens group comprises at least one aspheric lens; and / or

[0014] The first lens group comprises at least one lens with an Abbe number Vd≥60; and / or

[0015] The first lens group comprises at least one lens with a refractive index Nd≥1.8.

[0016] In some embodiments, the first lens group comprises, in order from the object side to the image side, a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, and a fourth lens with positive focal power, wherein the second lens is an aspheric lens, the third lens has an Abbe number Vd≥60, the fourth lens has a refractive index Nd≥1.90, and the third lens and the fourth lens are combined into a first cemented lens.

[0017] In some embodiments, the first cemented lens satisfies the following conditional expressions:

[0018] -1.0≤Vd3 / fy3+Vd4 / fy4≤1, (5)

[0019] |Vd3-Vd4|≥40, (6);

[0020] wherein Vd3 represents an Abbe number of the third lens, Vd4 represents an Abbe number of the fourth lens, fy3 represents a focal length of the third lens, and fy4 represents a focal length of the fourth lens.

[0021] In some embodiments, the second lens group includes at least one lens with an Abbe number Vd≥60.

[0022] In some embodiments, the second lens group includes, in order from the object side to the image side, a fifth lens with positive refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with positive refractive power, wherein the seventh lens and the eighth lens have an Abbe number Vd≥60, and the sixth lens and the seventh lens combine to form a second cemented lens.

[0023] In some embodiments, the sixth lens and the seventh lens satisfy the following conditional expression:

[0024] |Vd6-Vd7|≥40, (7);

[0025] wherein Vd6 represents an Abbe number of the sixth lens, and Vd7 represents an Abbe number of the seventh lens.

[0026] In some embodiments, the third lens group includes at least one lens with a refractive index Nd≥1.8.

[0027] In some embodiments, the third lens group includes, in order from the object side to the image side, a ninth lens with negative refractive power and a tenth lens with positive refractive power, wherein the tenth lens has a refractive index Nd≥1.8.

[0028] In some embodiments, the fourth lens group includes at least one aspherical lens.

[0029] In some embodiments, the fourth lens group includes, in order from the object side to the image side, an eleventh lens with positive refractive power, a twelfth lens with negative refractive power, a thirteenth lens with negative refractive power, and a fourteenth lens with positive refractive power, wherein the thirteenth lens is an aspherical lens.

[0030] In a second aspect, the present application provides an image pickup device, comprising an image sensor configured to receive an optical image formed by the internal focusing wide-angle camera lens, and the internal focusing wide-angle camera lens as described above.

[0031] The internal focusing wide-angle camera lens in the present application effectively offsets the dispersion phenomenon by reasonably configuring the combination of positive and negative lenses, ensures that there is no obvious chromatic aberration in the in-focus and out-of-focus pictures, realizes the imaging effect of natural transition from high light to dark part and clear level, at the same time, with the help of scientific power distribution, the spherical aberration and coma are effectively corrected, further improving the clarity of the whole picture, meeting the professional resolution requirement, also by simplifying the number of lenses, matching the internal focusing structure design of only the third lens group moving, effectively offsetting the dispersion, and significantly reducing the weight of the focusing group, shortening the focusing stroke, improving the driving efficiency, realizing fast and accurate automatic focusing, especially suitable for dynamic shooting scenes, the internal focusing wide-angle camera lens in the present application effectively controls the overall size of the lens and reduces the manufacturing cost, and has the excellent characteristics of high resolution, low dispersion and fast focusing, which can perfectly match the micro single camera considering the use scene of portability and professional imaging capability. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a structural schematic diagram provided by an embodiment of the present application;

[0033] Figure 2 is a spherical aberration schematic diagram when the internal focusing wide-angle camera lens in the present application is in the infinity focus state;

[0034] Figure 3 is a field curvature and distortion schematic diagram when the internal focusing wide-angle camera lens in the present application is in the infinity focus state;

[0035] Figure 4 is a spherical aberration schematic diagram when the internal focusing wide-angle camera lens in the present application is in the closest focus state;

[0036] Figure 5 is a field curvature and distortion schematic diagram when the internal focusing wide-angle camera lens in the present application is in the closest focus state. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0038] It should be understood that the term "include" as used in this specification and in the following claims indicates the presence of the described features, integers, steps, operations, elements, and / or components but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The terminology used in this description of the application merely for the purpose of describing particular embodiments of the application and is not intended to be limiting of the application. As used in this description of the application and in the claims that follow, the singular forms "a", "an", and "the" include the plural forms unless the context clearly indicates otherwise. The terms "first", "second", and similar terms do not imply any order, quantity, or importance, but are used to distinguish one element from another, and the terms "connected", "coupled", and similar terms are not limited to direct or physical connections, but can include an electrical connection, whether direct or indirect. "Up", "down", "left", "right", and similar terms are used to describe relative positions and can change when the absolute position of the described object changes.

[0039] In order to keep the following description of the embodiments of the present application clear and concise, detailed description of some known functions and known components is omitted in this specification.

[0040] The present application provides an internal focusing wide-angle photographic lens, which comprises, in order from the object side to the image side, a first lens group with negative focal power, a second lens group with positive focal power, an aperture stop, a third lens group with negative focal power, and a fourth lens group with positive focal power. During focusing from infinity to close range, the third lens group moves along the optical axis towards the image side, and the first lens group, the second lens group, and the fourth lens group remain unchanged relative to the image plane position.

[0041] The internal focusing wide-angle photographic lens satisfies the following conditional expressions:

[0042] 1.0 ≤ F2 / F ≤ 2.0, (1)

[0043] 1.0 ≤ F3 / F1 ≤ 3.0, (2)

[0044] 0.7 ≤ F / BF ≤ 3.0, (3)

[0045] D / TTL ≤ 0.5, (4)

[0046] wherein F1 represents the focal length of the first lens group, F2 represents the focal length of the second lens group, F3 represents the focal length of the third lens group, F represents the focal length of the internal focusing wide-angle photographic lens, BF represents the distance from the lens surface closest to the image plane to the image plane, D represents the maximum image plane diameter of the internal focusing wide-angle photographic lens, and TTL represents the total optical length of the internal focusing wide-angle photographic lens.

[0047] The inner focus type wide-angle camera lens in the embodiment of the present application effectively offsets the dispersion phenomenon through reasonable refractive power distribution of four lens groups and precise layout of the aperture stop, ensures that there is no obvious chromatic aberration in the in-focus and out-of-focus pictures, realizes natural transition and distinct level of imaging effect from high light to dark part, and effectively corrects the spherical aberration and coma, further improves the full picture definition. The third lens group moves from the object side to the image side during focusing, significantly reduces the weight of the focusing group, shortens the focusing stroke, improves the driving efficiency, realizes fast and accurate automatic focusing, reduces the change of aberration, ensures that the picture always maintains high sharpness and stability under different focusing distances, and has the excellent characteristics of high resolution, low dispersion and fast focusing.

[0048] The second lens group in the embodiment of the present application has positive refractive power, so that the light entering the lens can be focused. In addition, the focal length of the second lens group and the focal length of the inner focus type wide-angle camera lens satisfy: 1.0≤F2 / F≤2.0, so that if the ratio of the focal length of the second lens group to the focal length of the inner focus type wide-angle camera lens exceeds the upper limit, the refractive power borne by the second lens group is weak, at this time, more lens groups or more complex optical structures need to be introduced to compensate for the aberration problem caused by the too weak refractive power of the second lens group, thereby increasing the overall length and weight of the lens. If the ratio of the focal length of the second lens group to the focal length of the inner focus type wide-angle camera lens exceeds the lower limit, the refractive power borne by the second lens group is strong, the tolerance requirements of key parameters such as lens curvature, aspherical coefficient and thickness will be greatly increased, and small manufacturing errors or assembly deviations will be amplified, which directly affects the imaging quality and reduces the product yield.

[0049] The third lens group in the embodiment of the present application moves from the object side to the image side to realize focusing, and the axial spacing between the third lens group and the second lens group is adjusted to make the total refractive power of the combination of the two groups adaptively change. In addition, the focal length of the third lens group and the focal length of the first lens group satisfy: 1.0≤F3 / F1≤3.0, so that if the ratio of the focal length of the third lens group to the focal length of the first lens group exceeds the upper limit, the distance that the third lens group needs to move during focusing increases significantly, resulting in the lengthening of the focusing stroke from infinity to the nearest object distance. The too long focusing stroke directly prolongs the focusing response time, which cannot meet the fast focusing demand, especially affecting the follow-up performance of dynamic scene shooting or automatic focusing. If the ratio of the focal length of the third lens group to the focal length of the first lens group exceeds the lower limit, the refractive power borne by the third lens group is strong, the precision requirements of parameters such as lens curvature and refractive index are sharply increased, thereby the sensitivity of manufacturing tolerance and assembly deviation is increased, which is not conducive to production and assembly, and small errors may cause aberration correction failure and imaging clarity decline.

[0050] The distance from the lens surface closest to the image plane to the image plane and the focal length of the inner focus type wide-angle camera lens in the embodiment of the present application satisfy: 0.7≤F / BF≤3.0. If the ratio of the distance from the lens surface closest to the image plane to the image plane and the focal length of the inner focus type wide-angle camera lens exceeds the upper limit, the last lens of the lens is very close to the imaging plane, resulting in a very compact overall structure, even compression, which greatly squeezes the internal mechanical space of the lens, and may cause component interference, assembly out of place and other problems. If the ratio of the distance from the lens surface closest to the image plane to the image plane and the focal length of the inner focus type wide-angle camera lens exceeds the lower limit, the optical design difficulty is increased, and the light is difficult to converge accurately during propagation, which is prone to optical defects such as aberration and distortion, and is not conducive to achieving high resolution, and cannot present clear and delicate image effects.

[0051] The maximum image plane diameter of the inner focus type wide-angle camera lens and the total optical length of the inner focus type wide-angle camera lens in the embodiment of the present application satisfy: D / TTL≤0.5. If the ratio of the maximum image plane diameter and the total optical length exceeds the upper limit, the design space of the overall length of the lens is compressed, and the number of optical elements needs to be increased or the lens layout needs to be adjusted, resulting in that the volume of the lens cannot be effectively reduced, which is not conducive to the miniaturization design of the lens.

[0052] In some embodiments, the first lens group at least includes one aspheric lens; and / or the first lens group at least includes one lens with an Abbe number Vd≥60; and / or the first lens group at least includes one lens with a refractive index Nd≥1.8. The aspheric lens is used to correct distortion and astigmatism, so that the edge and center of the picture are consistent and the clarity is uniform, the lens with high Abbe number is used to suppress the dispersion deviation of light rays of different wavelengths, eliminate picture color separation, and ensure color restoration accuracy, and the lens with high refractive index is used to improve light refraction efficiency, greatly reduce the diameter of the lens and the aperture of the lens, and reduce stray light, thereby improving the brightness and contrast of the picture.

[0053] In some embodiments, the first lens group sequentially includes a first lens with negative optical power, a second lens with negative optical power, a third lens with negative optical power, and a fourth lens with positive optical power from the object side to the image side, wherein the second lens is an aspheric lens, the Abbe number Vd of the third lens is greater than or equal to 60, and the refractive index Nd of the fourth lens is greater than or equal to 1.90. The third lens and the fourth lens are combined into a first cemented lens. In the first lens group, the second lens is designed as an aspheric lens, which can effectively reduce the aperture of the front end of the lens and correct distortion and astigmatism. The third lens and the fourth lens are combined into a first cemented lens, which can effectively correct the field curvature while effectively correcting the vertical chromatic aberration and axial chromatic aberration.

[0054] In some embodiments, the first cemented lens satisfies the following conditional expression:

[0055] -1.0≤Vd3 / fy3+Vd4 / fy4≤1, (5)

[0056] |Vd3-Vd4|≥40, (6);

[0057] wherein Vd3 represents the Abbe number of the third lens, Vd4 represents the Abbe number of the fourth lens, fy3 represents the focal length of the third lens, and fy4 represents the focal length of the fourth lens.

[0058] The embodiment of the present application balances the dispersion and focal length ratio of the two lenses, avoids overcompensation or insufficient compensation of dispersion, provides precise parameter constraints for chromatic aberration correction, ensures stable overall optical performance of the first cemented lens, does not affect the focusing accuracy and imaging consistency of the lens, utilizes the significant difference in Abbe numbers of the third lens and the fourth lens to form a strong dispersion complementary effect, efficiently offsets axial and lateral chromatic aberrations, effectively reduces field curvature, and greatly reduces the imaging deviation of light rays of different wavelengths.

[0059] In some embodiments, the second lens group at least includes a lens with an Abbe number Vd≥60, which can focus secondary correction of chromatic aberration, further offset the remaining dispersion deviation, make the color restoration of the picture more pure and without color deviation, and form a complement with the high-Abbe-number lens of the first lens group to strengthen the color uniformity of the full field of view and adapt to high-pixel imaging requirements.

[0060] In some embodiments, the second lens group sequentially includes, from the object side to the image side, a fifth lens with positive refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with positive refractive power, wherein the Abbe number Vd of the seventh lens and the eighth lens is greater than or equal to 60, the sixth lens and the seventh lens are combined into a second cemented lens, and two high-Abbe-number lenses are arranged in the second lens group. While ensuring high resolution of the maximum aperture F1.8, the axial chromatic aberration correction effect can be further optimized to ensure accurate color restoration of the lens in and out of focus without obvious color edge performance.

[0061] In some embodiments, the sixth lens and the seventh lens satisfy the following conditional expression:

[0062] |Vd6-Vd7≥40, (7);

[0063] wherein Vd6 represents the Abbe number of the sixth lens, and Vd7 represents the Abbe number of the seventh lens.

[0064] The sixth lens and the seventh lens in the embodiment of the present application have a significant Abbe number difference, can form effective complementary dispersion characteristics, can effectively offset axial and lateral chromatic aberrations, and greatly reduce the imaging deviation of light rays of different wavelengths, which helps to realize precise dispersion control in a compact structure, optimizes imaging color consistency, avoids picture edge color deviation and color separation, and ensures full field of view color restoration accuracy.

[0065] In some embodiments, the third lens group at least includes a lens with a refractive index Nd greater than or equal to 1.8, which can more effectively control the convergence state of edge light rays, significantly reduce coma, and improve the imaging clarity and shape restoration ability of the edge field of view of the lens. The lens with high refractive index also has strong light deflection ability, which helps to compress the lens curvature and aperture, thereby realizing the miniaturization design and high resolution output of the lens.

[0066] In some embodiments, the third lens group sequentially includes a ninth lens with negative refractive power and a tenth lens with positive refractive power from the object side to the image side, and the refractive index Nd of the tenth lens is greater than or equal to 1.8. The third lens group is a focusing group that can move, and the focusing group uses a high refractive index lens, which not only effectively shortens the focusing stroke, reduces the weight of the focusing group, and improves the focusing speed, but also helps to realize the miniaturization design of the lens.

[0067] In some embodiments, the fourth lens group at least includes an aspherical lens, which can concentrate on correcting astigmatism, field curvature and distortion, so that light rays of different fields of view can be accurately converged on the image plane, the picture flatness is higher, the optical structure is simplified, and the cost control and imaging quality stability are considered.

[0068] In some embodiments, the fourth lens group sequentially includes an eleventh lens with positive refractive power, a twelfth lens with negative refractive power, a thirteenth lens with negative refractive power, and a fourteenth lens with positive refractive power from the object side to the image side, and the thirteenth lens is an aspherical lens, which can effectively eliminate field curvature, distortion and coma, and further improve the overall optical imaging quality.

[0069] The inner focusing wide-angle camera lens in the application effectively offsets the dispersion phenomenon by reasonably configuring the combination of positive and negative lenses, ensures that there is no obvious chromatic aberration in the in-focus and out-of-focus pictures, realizes the imaging effect of natural transition from high light to dark part and clear level, at the same time, effectively corrects the spherical aberration and coma by means of scientific power distribution, further improves the full picture definition, meets the professional resolution requirement, also effectively offsets the dispersion by simplifying the number of lenses and matching the inner focusing structure design of only the third lens group moving, significantly reduces the weight of the focusing group, shortens the focusing stroke, improves the driving efficiency, realizes the rapid and accurate automatic focusing, especially suitable for dynamic shooting scenes, the inner focusing wide-angle camera lens in the application effectively controls the overall size of the lens and reduces the manufacturing cost, and has the excellent characteristics of high resolution, low dispersion and rapid focusing, which can perfectly match the micro single camera and consider the use scene of portability and professional imaging capability.

[0070] The specific implementation of the application is described in detail in combination with specific embodiments as follows:

[0071] Embodiment one:

[0072] Figure 1 The structure schematic diagram of the inner focusing wide-angle camera lens provided by the embodiment one of the application is shown. For the convenience of description, only the part related to the embodiment of the application is shown, and the details are as follows:

[0073] As shown in Figure 1 , in the embodiment, the first lens group G1 includes, from the object side to the image side, a first lens L01 with negative refractive power, a second lens L02 with negative refractive power, a third lens L03 with negative refractive power, a fourth lens L04 with positive refractive power, wherein the second lens L02 is an aspherical lens, the third lens L03 and the fourth lens L04 are combined into a first cemented lens, the Abbe number Vd3 of the third lens L03 is 81.61, the refractive index Nd4 of the fourth lens is 1.88. The second lens group G2 includes, from the object side to the image side, a fifth lens L05 with positive refractive power, a sixth lens L06 with negative refractive power, a seventh lens L07 with positive refractive power, and an eighth lens L08 with positive refractive power, wherein the sixth lens L06 and the seventh lens L07 are combined into a second cemented lens, the Abbe number Vd7 of the seventh lens L07 is 81.61, and the Abbe number Vd8 of the eighth lens L08 is 81.61. The third lens group G3 includes, from the object side to the image side, a ninth lens L09 with negative refractive power, a tenth lens L10 with positive refractive power, and the refractive index Nd10 of the tenth lens L10 is 1.99. The fourth lens group G4 includes, from the object side to the image side, an eleventh lens L11 with positive refractive power, a twelfth lens L12 with negative refractive power, a thirteenth lens L13 with negative refractive power, and a fourteenth lens L14 with positive refractive power.

[0074] The Abbe number of the third lens is Vd3 = 81.61 for light having a wavelength of 587.6 nm, the Abbe number of the fourth lens is Vd4 = 24.78 for light having a wavelength of 587.6 nm, and the following conditional expression is satisfied:

[0075] -1.0 ≤ Vd3 / fy3 + Vd4 / fy4 ≤ 1, (5);

[0076] |Vd3 - Vd4| ≥ 20, (6);

[0077] The Abbe number of the sixth lens is Vd6 = 26.48 for light having a wavelength of 587.6 nm, the Abbe number of the seventh lens is Vd7 = 81.61 for light having a wavelength of 587.6 nm, and the following conditional expression is satisfied:

[0078] |Vd5 - Vd6| ≥ 20, (7).

[0079] Figure 2 and Figure 3 Fig. 6 shows the spherical aberration, the field curve and the distortion curve at infinity of the optical lens assembly according to the first embodiment of the present application. The spherical aberration curve at infinity represents the spherical aberration curve at an aperture number of 1.0, wherein the F line, the D line and the C line represent the spherical aberration at a wavelength of 486 nm, a wavelength of 587 nm and a wavelength of 656 nm, respectively, the abscissa represents the spherical aberration value, and the ordinate represents the field. The field curve at infinity represents the field curve at a half field angle ω of 47.0°, wherein the dotted line S represents the value of the chief ray D line on the sagittal image plane, the solid line T represents the value of the chief ray D line on the tangential image plane, the abscissa represents the field curvature value, and the ordinate represents the field. The distortion curve at infinity represents the distortion curve at a half field angle ω of 47.0°, wherein the abscissa represents the distortion value, and the ordinate represents the field.

[0080] Figure 4 and Figure 5 Fig. 7 shows the spherical aberration, the field curve and the distortion curve at the closest distance of focus of the optical lens assembly according to the first embodiment of the present application. The spherical aberration curve at the closest distance of focus represents the spherical aberration curve at an aperture number of 1.0, wherein the F line, the D line and the C line represent the spherical aberration at a wavelength of 486 nm, a wavelength of 587 nm and a wavelength of 656 nm, respectively, the abscissa represents the spherical aberration value, and the ordinate represents the field. The field curve at the closest distance of focus represents the field curve at a half field angle ω of 45.3°, wherein the dotted line S represents the value of the chief ray D line on the sagittal image plane, the solid line T represents the value of the chief ray D line on the tangential image plane, the abscissa represents the field curvature value, and the ordinate represents the field. The distortion curve at the closest distance of focus represents the distortion curve at a half field angle ω of 45.3°, wherein the abscissa represents the distortion value, and the ordinate represents the field.

[0081] As can be seen from Figs. 2-5, the photographic lens of the first embodiment of the present application has good imaging effect.

[0082] In this embodiment, the specific numerical data of the inner focusing wide-angle photographic lens are shown in Tables 1-3:

[0083] Table 1

[0084]

[0085]

[0086] Each aspherical surface can be defined by, but not limited to, the following formula:

[0087]

[0088] wherein x is the sag of the aspherical surface at a position along the optical axis at a height of h from the vertex of the aspherical surface; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the inverse of the radius of curvature R in Table 1 above); k is the conic coefficient; and Ai is the correction coefficient of the i-th order of the aspherical surface.

[0089] Table 2 shows the conic coefficient k and the correction coefficient of each order of the aspherical surface.

[0090] Table 2

[0091]

[0092] Table 3

[0093]

[0094] The present application also provides an image pickup device comprising an image sensor configured to receive an optical image formed by the inner focusing wide-angle photographic lens and the inner focusing wide-angle photographic lens as described above.

[0095] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the scope of the disclosure involved in the above embodiments is not limited to the technical solutions formed by the specific combinations of the technical features described above, and should also cover other technical solutions formed by any combinations of the technical features described above or their equivalent features without departing from the above disclosed concept. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

[0096] Moreover, while operations are depicted in a particular order, this should not be understood as requiring such an order, unless otherwise specifically stated, e.g., "then" has no particular temporal requirement. One will further appreciate that a "process" could include any set of operations, which are activities or sub- processes, and can sometimes be referred to or described as, for example, "functions," "procedures," "methods," etc. Conversely, an individual operation of the process could be called out separately or can sometimes be described in a sub- process or function, although the operation can also be executed independently. One will also appreciate that a "process" could include some activities or steps that are combined with other activities or steps to further achieve an exchange of information between multiple devices, e.g., those of a service provider and a hardware vendor. These modifications do not result in a change of the essence of the representations and processes being exchanged.

Claims

1. An internal focusing wide-angle photographic lens characterized by comprising, in order from the object side, From the object side to the image side, the first lens group with negative focal length, the second lens group with positive focal length, the aperture stop, the third lens group with negative focal length and the fourth lens group with positive focal length are sequentially arranged, and during the focusing process from infinity to close range, the third lens group moves along the optical axis to the image side, and the first lens group, the second lens group and the fourth lens group remain unchanged relative to the image plane position; The first lens group is sequentially composed of a first lens with negative focal length, a second lens with negative focal length, a third lens with negative focal length and a fourth lens with positive focal length from the object side to the image side; the second lens group is sequentially composed of a fifth lens with positive focal length, a sixth lens with negative focal length, a seventh lens with positive focal length and an eighth lens with positive focal length from the object side to the image side; the third lens group is sequentially composed of a ninth lens with negative focal length and a tenth lens with positive focal length from the object side to the image side; the fourth lens group is sequentially composed of an eleventh lens with positive focal length, a twelfth lens with negative focal length, a thirteenth lens with negative focal length and a fourteenth lens with positive focal length from the object side to the image side; The inner focusing wide-angle photographic lens satisfies the following conditional expressions: 1.0≤F2 / F≤2.0, (1); 1.0≤F3 / F1≤3.0, (2); 0.7≤F / BF≤3.0, (3); D / TTL≤0.5, (4); Wherein, F1 represents the focal length of the first lens group, F2 represents the focal length of the second lens group, F3 represents the focal length of the third lens group, F represents the focal length of the inner focusing wide-angle photographic lens, BF represents the distance from the lens surface closest to the image plane to the image plane, D represents the maximum image plane diameter of the inner focusing wide-angle photographic lens, and TTL represents the total optical length of the inner focusing wide-angle photographic lens.

2. The internal focusing wide-angle photographic lens according to claim 1, characterized by The first lens group comprises at least one aspheric lens; and / or The first lens group comprises at least one lens with Abbe number Vd≥60; and / or The first lens group comprises at least one lens with refractive index Nd≥1.

8.

3. The internal focusing wide-angle photographic lens according to claim 1, wherein The second lens is an aspheric lens, the Abbe number Vd of the third lens is greater than or equal to 60, the refractive index Nd of the fourth lens is greater than or equal to 1.90, and the third lens and the fourth lens are combined into a first cemented lens.

4. The internal focusing wide-angle photographic lens according to claim 3, wherein The first cemented lens satisfies the following conditional expressions: -1.0≤Vd3 / fy3+Vd4 / fy4≤1, (5); |Vd3-Vd4|≥40, (6); Wherein, Vd3 represents the Abbe number of the third lens, Vd4 represents the Abbe number of the fourth lens, fy3 represents the focal length of the third lens, and fy4 represents the focal length of the fourth lens.

5. The internal focusing wide-angle photographic lens according to claim 1, wherein The second lens group comprises at least one lens with Abbe number Vd≥60.

6. The internal focusing wide-angle photographic lens according to claim 1, wherein The Abbe number Vd of the seventh lens and the eighth lens is greater than or equal to 60, and the sixth lens and the seventh lens are combined into a second cemented lens.

7. The internal focusing wide-angle photographic lens according to claim 6, wherein The sixth and seventh lenses satisfy the following conditional expression: | Vd6 - Vd7 | ≥ 40, (7); wherein Vd6 represents the Abbe number of the sixth lens, and Vd7 represents the Abbe number of the seventh lens.

8. The internal focusing wide-angle photographic lens according to claim 1, wherein The third lens group includes at least one lens having a refractive index Nd ≥ 1.

8.

9. The internal focusing wide-angle photographic lens according to claim 1, wherein The tenth lens has a refractive index Nd ≥ 1.

8.

10. The internal focusing wide-angle photographic lens according to claim 1, wherein The fourth lens group includes at least one aspheric lens.

11. The internal focusing wide-angle photographic lens according to claim 1, characterized in that, The thirteenth lens is an aspheric lens.

12. An image pickup device, characterized by comprising: An image sensor configured to receive an optical image formed by the intrafocal wide-angle photographic lens.

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