Internal focusing lens and camera module

Abstract

The invention provides an internal focusing lens and a camera module, and the internal focusing lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens. Wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens form an upper-group lens (group) and a lower-group lens (group), the upper-group lens (group) is located at the front end of the light incidence direction of the lower-group lens (group), and the lower-group lens (group) is located at the rear end of the light incidence direction of the lower-group lens (group). The upper group lens (group) can move along the optical axis direction relative to the lower group lens (group), and when the object distance changes, the position of the upper group lens (group) is adjusted to change the gap between the upper group lens (group) and the lower group lens (group), so that the image space position corresponding to the inner focusing lens is not changed.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging technology, and in particular to an internal focus lens and a camera module. Background Art

[0002] Today, people's lives have entered a rapidly developing digital age. Mobile phones, as essential electronic communication devices, have seen unprecedented performance improvements compared to traditional models. Especially in the field of mobile photography, new technologies are constantly emerging, improving, and maturing. The most obvious of these is the reduction in weight and thickness of mobile phones—this greatly improves the user experience, but also places higher demands on the optical design of mobile phone lenses: this means shorter overall lens lengths while maintaining the same satisfactory image quality.

[0003] Existing mobile phone lenses focus by shifting the image plane at different object distances. This approach shifts the image plane position further back at closer object distances, resulting in a longer overall optical length at close ranges. Clearly, this approach is detrimental to achieving thinner and lighter phones. To address this issue, a series of height-reduction solutions, such as liquid lenses and free-form surfaces, have been successfully implemented in mobile phone lens designs.

[0004] Although the use of liquid lenses or TLENS can achieve focusing at different object distances while ensuring that the image plane position remains unchanged by changing its own optical power, most mobile phone lenses currently use aspherical lenses. Changing the R value of the spherical surface and thus changing the optical power often introduces excessive field curvature. At the same time, due to the thickness limit of the liquid lens or TLENS itself, it is difficult to compress the total optical length in the initial state to a very ideal state. The main purpose of the free-form surface height reduction solution is to reduce the total optical length in the initial state, but the existing focusing method is still used. This is still not recommended for some lenses: for example, if a small head requires the TTL to remain unchanged to ensure that the head size remains unchanged, it is difficult to achieve this requirement through this method. In addition, for large image plane or telephoto lens designs, the ordinary focusing method causes the image plane to move too far at different object distances, and the free-form surface height reduction cannot compensate for this defect. Summary of the Invention

[0005] A major advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens uses internal focus technology, that is, at least one lens of the internal focus lens is driven by a motor, and the image plane position of the internal focus remains unchanged, thereby completing focusing at different object distances, which is beneficial to shortening the total length of the lens.

[0006] Another advantage of the present invention is that it provides an inner focus lens and a camera module, wherein the inner focus lens can effectively improve the field curvature under different object distances while keeping the image plane unchanged.

[0007] Another advantage of the present invention is that it provides an internal focus lens and camera module, wherein internal focus of the lens is achieved by moving the lens spacing while keeping the image plane position unchanged, thereby improving the image quality at close range to a certain extent.

[0008] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens maintains the image plane position unchanged by moving at least one lens (lens group), reducing the back focus, thereby facilitating a reduction in the total length of the lens (TTL).

[0009] Another advantage of the present invention is to provide an inner focus lens and a camera module, wherein the inner focus lens can reduce close-range field curvature, thereby improving image quality.

[0010] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens maintains the image plane position unchanged through internal focusing, achieves focusing at different object distances, and effectively reduces the module height.

[0011] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens maintains the image plane position unchanged through internal focusing, achieves focusing at different object distances, and can effectively improve the close-range performance of the camera module.

[0012] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens includes seven non-bonded aspheric lenses with optical focal length, and at least one lens is configured as a movable lens (group), which can be moved along the optical axis to provide positive optical focal length. When the object distance changes, the image space position corresponding to the moving group remains stationary, thereby making the object distance of the group corresponding to the moving group unchanged, thereby achieving the fixation of the image plane position.

[0013] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens achieves a larger object distance variation range through a smaller stroke, achieves a fixed image plane position compared to an ordinary lens, and greatly improves the field curvature performance of the lens compared to a TLENS lens.

[0014] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the first lens of the internal focus lens is a lens with positive optical power and the second lens is a lens with negative refractive power, which can effectively reduce the distortion of the optical system.

[0015] Another advantage of the present invention is that it provides an inner-focus lens and a camera module, wherein the seventh lens element of the inner-focus lens is a negative optical power lens and an M-type lens, which can effectively improve the field curvature of the optical system.

[0016] Another advantage of the present invention is that it provides an internal focus lens and a camera module, wherein the internal focus lens can effectively reduce the chromatic aberration of the imaging of the camera module, thereby improving the imaging quality.

[0017] According to one aspect of the present invention, an internal focus lens of the present invention that can achieve the aforementioned objects and other objects and advantages includes:

[0018] a first lens;

[0019] a second lens;

[0020] a third lens;

[0021] a fourth lens;

[0022] a fifth lens;

[0023] a sixth lens; and

[0024] a seventh lens, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are arranged in sequence along an optical axis from the object side to the image side, and are spaced apart from each other. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens form an upper lens group (group) and a lower lens group (group), wherein the upper lens group (group) is located at the front end of the lower lens group (group) in the light incident direction, and the upper lens group (group) is movable relative to the lower lens group (group) along the optical axis. When the object distance changes, the gap between the upper lens group (group) and the lower lens group (group) is changed by adjusting the position of the upper lens group (group), so that the image space position corresponding to the inner focus lens remains unchanged.

[0025] According to at least one embodiment of the present invention, the first lens, the second lens, the third lens, the fourth lens, and the fifth lens constitute the upper lens group, and the sixth lens and the seventh lens constitute the lower lens group.

[0026] According to at least one embodiment of the present invention, the first lens, the second lens, and the third lens constitute the upper lens group, the fifth lens, the sixth lens, and the seventh lens constitute the lower lens group, the fourth lens is configured as a middle lens group, and focusing is achieved by adjusting the position of the middle lens group.

[0027] According to at least one embodiment of the present invention, the first lens has a positive optical power, and the second lens has a negative optical power.

[0028] According to at least one embodiment of the present invention, the seventh lens has a negative optical power, and the seventh lens has the shape of an M-type lens.

[0029] According to at least one embodiment of the present invention, the focal length of the internal focusing lens is f, the focal length of the movable lens (group) is fM, the focal length of the nth lens is fn, the radius of curvature of the nth lens near the object side is RLnS1, the radius of curvature of the nth lens near the object side is RLnS2, and the maximum stroke of the movable lens (group) is AFD, which satisfies the following conditions: 0.8 < fM / f < 2.9; |∑fn| / f > 1.6; 1.84 < ∑RLnS1 / RLnS2 < 8; 0.09 < AFD < 0.5, and the upper group lens (group) and / or the lower group lens (group) provides positive optical power.

[0030] According to at least one embodiment of the present invention, let the thickness of the nth lens on the optical axis be CTn, the total optical length of the optical system of the internal focusing lens be TTL, and the semi-image height of the image plane be ImgeH. Focusing is achieved by moving the movable lens (group), which satisfies the following conditions: 0.05 < CT1 / TTL < 0.15; TTLmax - TTLmin < 0.5; 0.6 < TTL object distance / (2 * ImgeH) < 0.8; the gap between any two adjacent lens groups is greater than 0.18.

[0031] According to at least one embodiment of the present invention, the object side surface of the first lens is convex, the image side surface of the first lens is concave, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, the object side surface of the fourth lens is concave, the image side surface of the fourth lens is convex, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is concave, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is convex, the object side surface of the seventh lens is concave, and the image side surface of the seventh lens is concave.

[0032] According to at least one embodiment of the present invention, the aspheric curve equations of the respective lenses of the internal focusing lens are expressed as follows:

[0033]

[0034] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0035] According to another aspect of the present invention, the present invention further provides a camera module, comprising:

[0036] An internal focus lens;

[0037] a photosensitive component, wherein the inner focus lens is disposed on the photosensitive component; and

[0038] At least one inner focus motor, wherein the inner focus lens comprises:

[0039] a first lens;

[0040] a second lens;

[0041] a third lens;

[0042] a fourth lens;

[0043] a fifth lens;

[0044] a sixth lens; and

[0045] a seventh lens, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are arranged in sequence along an optical axis from the object side to the image side, and are spaced apart from each other. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens form an upper lens group and a lower lens group, wherein the upper lens group is located at the front end of the lower lens group in the light incident direction, and the upper lens group is movable relative to the lower lens group along the optical axis. When the object distance changes, the inner focus motor changes the gap between the upper lens group and the lower lens group by driving the upper lens group, so that the image space position corresponding to the inner focus lens remains unchanged.

[0046] According to at least one embodiment of the present invention, the first lens, the second lens, the third lens, the fourth lens, and the fifth lens constitute the upper lens group, and the sixth lens and the seventh lens constitute the lower lens group.

[0047] According to at least one embodiment of the present invention, the first lens, the second lens, and the third lens form the upper group of lenses (lens group), the fifth lens, the sixth lens, and the seventh lens form the lower group of lenses (lens group), the fourth lens is arranged as a middle group of lenses (lens group), and focusing is achieved by adjusting the position of the middle group of lenses (lens group).

[0048] According to at least one embodiment of the present invention, the first lens has a positive optical power, and the second lens has a negative optical power.

[0049] According to at least one embodiment of the present invention, the seventh lens has a negative optical power, and the seventh lens adopts the shape of an M-type lens.

[0050] According to at least one embodiment of the present invention, the focal length of the internal focusing lens is f, the focal length of the movable lens (lens group) is fM, the focal length of the nth lens is fn, the curvature radius of the nth lens near the object side is RLnS1, the curvature radius of the nth lens near the object side is RLnS2, the maximum stroke of the movable lens (lens group) is AFD, and it satisfies the following conditions: 0.8 < fM / f < 2.9; |∑fn| / f > 1.6; 1.84 < ∑RLnS1 / RLnS2 < 8; 0.09 < AFD < 0.5, and the upper group of lenses (lens group) and / or the lower group of lenses (lens group) provide positive optical power.

[0051] According to at least one embodiment of the present invention, let the thickness of the nth lens on the optical axis be CTn, the total optical length of the optical system of the internal focusing lens be TTL, and the semi-image height of the image plane be ImgeH. Focusing is achieved by moving the movable lens (lens group), and it satisfies the following conditions: 0.05 < CT1 / TTL < 0.15; TTLmax - TTLmin < 0.5; 0.6 < TTL object distance / (2 * ImgeH) < 0.8; the gap between any two adjacent lens groups is greater than 0.18.

[0052] According to at least one embodiment of the present invention, the object side surface of the first lens is convex, the image side surface of the first lens is concave, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, the object side surface of the fourth lens is concave, the image side surface of the fourth lens is convex, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is concave, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is convex, the object side surface of the seventh lens is concave, and the image side surface of the seventh lens is concave.

[0053] According to at least one embodiment of the present invention, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0054]

[0055] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0056] Further objects and advantages of the present invention will be fully apparent from an understanding of the following description and accompanying drawings.

[0057] These and other objects, features and advantages of the present invention will be more fully understood from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 FIG. 1 is a structural diagram of an inner focus lens according to a first preferred embodiment of the present invention.

[0059] Figure 2A and Figure 2B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the first preferred embodiment of the present invention.

[0060] Figure 3A and Figure 3B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the first preferred embodiment of the present invention.

[0061] Figure 4A and Figure 4B axial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the first preferred embodiment of the present invention.

[0062] Figure 5 FIG. 4 is a schematic structural diagram of an inner focus lens according to a second preferred embodiment of the present invention.

[0063] Figure 6A and Figure 6B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the second preferred embodiment of the present invention.

[0064] Figure 7A and Figure 7B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the second preferred embodiment of the present invention.

[0065] Figure 8A and Figure 8Baxial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the second preferred embodiment of the present invention.

[0066] Figure 9A and Figure 9B FIG. 4 is a schematic structural diagram of an inner focus lens according to a third preferred embodiment of the present invention.

[0067] Figure 10A and Figure 10B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the third preferred embodiment of the present invention.

[0068] Figure 11A and Figure 11B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the third preferred embodiment of the present invention.

[0069] Figure 12A and Figure 12B axial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the third preferred embodiment of the present invention.

[0070] Figure 13A and Figure 13B FIG. 4 is a schematic structural diagram of an inner focus lens according to a fourth preferred embodiment of the present invention.

[0071] Figure 14A and Figure 14B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the fourth preferred embodiment of the present invention.

[0072] Figure 15A and Figure 15B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the fourth preferred embodiment of the present invention.

[0073] Figure 16A and Figure 16B axial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the fourth preferred embodiment of the present invention.

[0074] Figure 17A and Figure 17B FIG. 4 is a structural diagram of an inner focus lens according to a fifth preferred embodiment of the present invention.

[0075] Figure 18A and Figure 18B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the fifth preferred embodiment of the present invention.

[0076] Figure 19A and Figure 19B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the fifth preferred embodiment of the present invention.

[0077] Figure 20A and Figure 20B axial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the fifth preferred embodiment of the present invention.

[0078] Figure 21A and Figure 21B FIG. 4 is a structural diagram of an inner focus lens according to a sixth preferred embodiment of the present invention.

[0079] Figure 22A and Figure 22B 1 is the distortion curve corresponding to different object distances of the inner focus lens according to the sixth preferred embodiment of the present invention.

[0080] Figure 23A and Figure 23B 1 is the astigmatism curve corresponding to different object distances of the inner focus lens according to the sixth preferred embodiment of the present invention.

[0081] Figure 24A and Figure 24B axial chromatic aberration curves corresponding to different object distances of the inner focus lens according to the sixth preferred embodiment of the present invention.

[0082] Figure 25 2 is a schematic diagram of a camera module using the inner focus lens of any of the above preferred embodiments of the present invention. DETAILED DESCRIPTION

[0083] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0084] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0085] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the elements may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0086] With reference to the accompanying drawings of the present invention Figures 1 to 4B As shown, an internal focus lens and a camera module according to the present invention are explained in the following description. The internal focus lens includes a first lens 10, a second lens 20, a third lens 30, a fourth lens 40, a fifth lens 50, a sixth lens 60 and a seventh lens 70, wherein the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, the fifth lens 50, the sixth lens 60 and the seventh lens 70 are arranged in sequence from the object side to the image side along the optical axis. It is worth mentioning that an aperture 100 (not shown in the figure) is located on the light incident side of the first lens 10, and at least one filter 200 is located on the light exit side of the seventh lens 70. The imaging light is incident on the first lens 10 of the internal focus lens through the aperture 100, and the optical fiber emitted by the seventh lens 70 is imaged at an image plane position S0 through the filter 200, that is, a photosensitive chip is located at the image plane position S0.

[0087] It is worth mentioning that, in this preferred embodiment of the present invention, each lens of the inner focus lens is a lens with optical power and a non-bonded aspheric surface, and at least one lens of the inner focus lens is a movable lens (group).

[0088] In detail, in this preferred embodiment of the present invention, at least one lens of the internal focus lens constitutes an upper group lens (group), and at least one lens constitutes a lower group lens (group), wherein the upper group lens (group) is movable relative to the lower group lens (group) along the optical axis, and the image plane position S0 is adjusted by adjusting the gap between the upper group lens (group) and the lower group lens (group) so that the image plane position S0 is maintained at the position of the photosensitive chip. In other optional embodiments of the present invention, at least one lens of the internal focus lens constitutes a middle group lens (group), wherein the middle group lens (group) is located between the upper group lens (group) and the lower group lens (group), and the position of the middle group lens (group) can be moved relative to the upper group lens (group) and / or the lower group lens (group) to achieve focusing of the camera module. In short, when the lenses of the inner focus lens are divided into three groups of lenses, the focusing of the lens is achieved by adjusting the position of the middle group lens (group), and the upper group lens (group) and the middle group lens (group) are movable lenses (groups); when the lenses of the inner focus lens are divided into two groups of lenses, the upper group lens (group) is a movable lens group, and the lower group lens group is a fixed position lens group. By moving the position of the movable lens (group), the image plane position S0 is always maintained at the position of the photosensitive chip.

[0089] The focal length of the inner focus lens is f, and the focal length of the movable lens (group) is f M The focal length of the upper lens group is f 上 , the focal length of the lower lens group is f 下 , let the focal length of the nth lens be fn, and the curvature radius of the nth lens close to the object be R LnS1 The curvature radius of the nth lens close to the object is R LnS2 The maximum stroke of the inner focus motor of the optical system of the inner focus lens is AFD max , which satisfies the following conditions: 0.8 <f M / f<2.9;|∑fn| / f>1.6;0.8<∑R LnS1 / R LnS2 <3.2; 0.09 <AFD max <0.5.

[0090] It is worth mentioning that the internal focusing motor drives the movable lens (group) of the internal focusing lens to move along the optical axis direction of the internal focusing lens, so that the movable lens provides a positive optical power. When the object distance changes, the image space position corresponding to the movable lens remains stationary. Thus, when the object distance changes, by adjusting the position of the movable lens (group), the fixed position of the image plane is achieved. Those skilled in the art can understand that the internal focusing lens according to the present invention realizes a larger object distance change range with a smaller stroke. Compared with ordinary lenses, the fixed position of the image plane is achieved. Compared with TLENS lenses, the field curvature performance of the lens is greatly improved. More worth mentioning is that for the internal focusing lens of the present invention with an object distance of 15 cm to 1.2 m, the field curvature of the full field of view can be less than 8 μm.

[0091] In the preferred embodiment of the present invention, the first lens 10 of the internal focusing lens has a positive optical power, and the second lens 20 has a negative optical power, effectively reducing the distortion of the optical system. And because the seventh lens 70 has a negative optical power and the seventh lens adopts the shape of an M-shaped lens, the field curvature of the optical system can be effectively improved.

[0092] Further, let the focal length of the upper group of lenses (group) be f 上 , the focal length of the lower group of lenses (group) be f 下 , the thickness of the nth lens on the optical axis be CTn, the total optical length of the optical system of the internal focusing lens be TTL, the back focal length of the internal focusing lens be BFL, the semi-image height of the chip D direction be ImgeH, and focusing is achieved by moving the movable lens (group). For the changing gap position, the gap between any two lens groups is SP, which satisfies the following conditions: 0.05 < CT1 / TTL < 0.15; TTL max -TTL min < 0.5; 0.6 < TTL / (2*ImgeH) < 0.8; SP ≥ 0.18; |f 上 / f 下 | < 1; 0.06 < BFL / TTL < 0.15; 0.015 < AFDmax / ImageH < 0.08. It is worth mentioning that if the internal focusing lens is divided into an upper group of lenses (group) and a lower group of lenses (group), then SP is the air gap between the upper group of lens groups and the lower group of lens groups; if the internal focusing lens is divided into an upper group of lenses (group), a middle group of lenses (group), and a lower group of lenses (group), then SP is the air gap between the upper group of lens groups and the middle group of lens groups, or the air gap between the middle group of lens groups and the lower group of lens groups.

[0093] Preferably, in this preferred embodiment of the present invention, the internal focusing lens satisfies the following conditional formula: 0.06 < BFL / TTL < 0.1.

[0094] The internal focusing lens of the present invention can be implemented as a small head lens, that is, the middle part of the first lens of the internal focusing lens is thicker, and the CT1 / TTL object distance value is relatively large, about 0.25, and it is necessary to ensure that the overall optical length is as small as possible and remains unchanged at different object distances. In this preferred embodiment of the present invention, the internal focusing lens can satisfy 0.6 < TTL / (2*ImgH) < 0.8 on the basis of keeping the overall optical length of the optical system unchanged, which can effectively solve the problem of small head lenses. The internal focusing lens of the present invention can also be implemented as a movable lens in two upper and lower groups or a movable lens in upper, middle and lower groups. The internal focusing lens of the present invention can also be implemented as a small image plane lens or a large image plane lens.

[0095] For a large image plane optical system, the change of the object distance of an ordinary lens will cause a large movement of the image plane position, which will lead to an increase in the overall module height. At the same time, the near field curvature of a large image plane usually has poor performance. The three-group internal focusing scheme can provide the smallest change in the overall length. By moving the upper group lens and the middle group lens, while keeping the image plane unchanged, the TTL change < 0.085. It is worth mentioning that, in addition to the three-group internal focusing scheme, the two-group internal focusing scheme can also greatly improve the field curvature at different object distances and can be used in optical systems with multiple object distances in most application scenarios.

[0096] It is worth mentioning that in the present invention, when the movable lens (group) of the internal focusing lens is in any effective position, the gap between it and the adjacent group opposite to it is > 0.18 mm, reserving enough space for structural design.

[0097] Summary of the invention; In the present invention, the lens is divided into several groups. The object corresponding to the first group (the upper group lens group) will form an intermediate image as the object of the second group (the middle group lens group or the lower group lens group), and so on, so as to form the final image on the final image plane. It can be seen that the position and image quality of the intermediate image of the penultimate group directly determine the presentation of the final image plane. When the object distance changes, the ordinary focusing method is to move the image plane to achieve focusing at the new object distance. In this way, the distance between the lenses does not change. Since the intermediate image of the penultimate group is the object of the last group, its position and image quality are almost impossible to be in the state of the object that provides the best imaging for the final imaging. When the object distance changes (usually at close range), at the focusing position of the central field of view, there is usually a large field curvature in most other outer fields of view. For a general mobile phone lens, it is hoped that focusing can be achieved from inf (infinity) to 10 cm. This focusing method seriously affects the close-range image quality. ?

[0098] Lens focusing achieves focus by moving the distance between lenses. When the object distance changes, the lens is split into several groups, and the spacing between the groups is altered, such as changing the spacing between the first and second groups, thereby changing the position and quality of the intermediate image. For example, when the object distance changes, the position of the intermediate image of the first group changes, causing the object distance of the second group to change. Optimizing the system by setting the spacing at different object distances as a variable helps us find the optimal relative position between the groups, ensuring that the intermediate image position and image quality of the penultimate group are more closely aligned to maximize final image quality. This, compared to traditional focusing solutions, is more conducive to improving field curvature.

[0099] Although too many groups can effectively improve image quality, the complex structure poses significant challenges to system stability and reliability. Here, we use a two-group or three-group focusing method to significantly improve the MTF image quality at close distances.

[0100] Referring to the accompanying drawings of the present invention Figures 1 to 4B As shown, an internal focus lens according to a first preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has positive focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has negative optical power, and the object side surface 51 of the fifth lens is concave, and the image side surface 52 of the fifth lens 50 is concave; the sixth lens 60 has positive optical power, wherein the object side surface 61 of the sixth lens 60 is convex, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative optical power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M The value of / f is 2.278877499; the value of |∑fn| / f is 1.68400519; ∑R LnS1 / R LnS2 The value is 1.61168; AFD max The value is 0.107; the CT1 / TTL value is 0.0979138; TTL max -TTL minThe value is 0.0711; the TTL / (2*ImgH) value is 0.658489; the SP value is 0.18; the BFL / TTL value is 0.112707574548256; the fup / fdown value is -0.92312612; and the ImageH value is 6.27.

[0101] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0102] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0103] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0104] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=6.58mm; Fno=1.8; and FOV=85 degrees.

[0105] Table 1 shows the structural parameters of each lens of the inner focus lens according to the first preferred embodiment of the present invention.

[0106] Table 1

[0107]

[0108]

[0109] Table 1 shows the detailed structural data of each lens of the inner-focus lens according to the first preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 2 shows the aspheric surface data of each lens of the inner-focus lens according to the first preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 1 and 2 of the embodiments and are not repeated here.

[0110] Table 2

[0111]

[0112]

[0113] Specifically, in this preferred embodiment of the present invention, the first lens 10, the second lens 20, and the third lens 30 of the inner focus lens comprise the upper lens group L1, the fifth lens 50, the sixth lens 60, and the seventh lens 70 comprise the lower lens group L2, and the fourth lens 40 is drivably disposed between the upper and lower lens groups. The fourth lens 40 of the inner focus lens is implemented as a movable lens, and the upper lens group is implemented as a movable lens group. That is, the fourth lens 40 can be driven by the inner focus motor to move along the optical axis, and the upper lens group can also be driven along the optical axis. It is understood that the fourth lens 40 can also be referred to as the middle lens group L3 of the inner focus motor. When the object distance changes, the inner focus motor drives the fourth lens 30 (the movable lens) to move to maintain the position of the image plane formed by the inner focus lens unchanged.

[0114] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, and the third lens 30 can be driven by the inner focus motor to move as a whole along the optical axis. The fourth lens 40, as a movable lens, can also be driven by the inner focus motor to move along the optical axis, thereby achieving a fixed imaging position of the inner focus lens. It is worth noting that in this preferred embodiment of the present invention, focusing is achieved by adjusting the position of the fourth lens 40 (the middle lens group).

[0115] Table 3 shows the basic parameters of the internal focus lens according to the first preferred embodiment of the present invention.

[0116] Table 3

[0117] Half image height 6.27 MIC 6.15 Fno 1.8 inf wavelength 650:610:555:510:470＝107:503:1000:503:91 TTL 8.1 inf 8.1711 30cm IR 0.21 FOV 85.00000643 inf 84.80918708 30cm DISTORTIONOPTICAL 2.30％ inf RI 25.00％ D direction Object distance range 30CM~INF Number of groups 3 AF Itinerary 35.7UM Upper group and middle group 107UM Middle group and lower group Upper-middle group gap 0.634398185 inf 0.598712732 30cm Middle and lower group gap 0.180000555 inf 0.287407939 30cm

[0118] In this preferred embodiment of the present invention, the image plane formed by the internal focus lens has a half-image height (ImgH) of 6.27. For example, the variable object distance is from 30 cm to infinity. When the object distance is infinite, the total optical length (TTL) of the optical system of the internal focus lens is 8.1 mm. When the object distance is 30 cm, the total optical length (TTL) of the internal focus lens is 8.1711 mm. When the object distance is infinite, the maximum angle of view (FOV) of the optical projection lens of the internal focus lens is 85.0000064280624. When the object distance is 30 cm, the maximum angle of view (FOV) of the optical projection lens of the internal focus lens is 84.8091870819496. In this preferred embodiment of the present invention, the travel distance along the optical axis between the upper lens group and the fourth lens 40 (movable lens) is 35.7 μm; the travel distance along the optical axis between the lower lens group and the fourth lens 40 (movable lens) is 107 μm. When the object distance is infinite, the gap between the fourth lens 40 and the upper lens group is 0.634398185366369 mm, and the gap between the fourth lens 40 and the lower lens group is 0.180000554563717. When the object distance is 30 cm, the gap between the fourth lens 40 and the upper lens group is 0.59871273237129 mm, and the gap between the fourth lens 40 and the lower lens group is 0.287407938865411.

[0119] Figure 2A and 2B The following diagram shows the distortion curves for the inner-focus lens according to the first preferred embodiment of the present invention at object distances of infinity and 30 cm. It can be seen that the inner-focus lens according to the first preferred embodiment of the present invention effectively reduces lens distortion. In particular, when the object distance is infinite, the distortion of the inner-focus lens is less than 2.30%. Figure 3A and Figure 3B 1. The astigmatism curves corresponding to the inner focus lens of the first preferred embodiment of the present invention when the object distance is infinite and 30 cm are shown; Figure 4A and Figure 4B The chromatic aberration curves on each axis for the inner focus lens of the first preferred embodiment of the present invention at object distances of infinity and 30 cm are shown. It can be seen that the inner focus lens of the first preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0120] Referring to the accompanying drawings of the present invention Figures 5 to 8BAs shown, an internal focus lens according to a second preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has positive focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has negative optical power, and the object side surface 51 of the fifth lens is concave, and the image side surface 52 of the fifth lens 50 is concave; the sixth lens 60 has positive optical power, wherein the object side surface 61 of the sixth lens 60 is convex, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative optical power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M The value of / f is 2.856874385; the value of |∑fn| / f is 2.131044602; ∑R LnS1 / R LnS2 The value is 1.48868; AFD max The value is 0.093; the CT1 / TTL value is 0.0872464; TTL max -TTL min The value is 0.0644; the TTL / (2*ImgH) value is 0.661929; the SP value is 0.19; the BFL / TTL value is 0.113696896591513; the fup / fdown value is -0.89123344; and the ImageH value is 5.42.

[0121] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0122] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0123] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0124] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=5.8mm; Fno=2; and FOV=85 degrees.

[0125] Table 4 shows the structural parameters of each lens of the inner focus lens according to the second preferred embodiment of the present invention.

[0126] Table 4

[0127]

[0128] Table 4 shows detailed structural data for each lens of the inner-focus lens according to the second preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 5 shows aspheric surface data for each lens of the inner-focus lens according to the second preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 4 and 5 of the embodiments and are not further elaborated here.

[0129] Table 5

[0130]

[0131] Specifically, in this preferred embodiment of the present invention, the first lens 10, the second lens 20, and the third lens 30 of the inner focus lens comprise the upper lens group L1, the fifth lens 50, the sixth lens 60, and the seventh lens 70 comprise the lower lens group L2, and the fourth lens 40 is drivably disposed between the upper and lower lens groups. The fourth lens 40 of the inner focus lens is implemented as a movable lens, and the upper lens group is implemented as a movable lens group. That is, the fourth lens 40 can be driven by the inner focus motor to move along the optical axis, and the upper lens group can also be driven along the optical axis. It is understood that the fourth lens 40 can also be referred to as the middle lens group L3 of the inner focus motor. When the object distance changes, the inner focus motor drives the fourth lens 30 (the movable lens) to move to maintain the position of the image plane formed by the inner focus lens unchanged.

[0132] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, and the third lens 30 can be driven by the inner focus motor to move as a whole along the optical axis; the fourth lens 40, as a movable lens, can also be driven by the inner focus motor to move along the optical axis, thereby achieving a fixed imaging position of the inner focus lens.

[0133] Table 6 shows the basic parameters of the internal focus lens according to the second preferred embodiment of the present invention.

[0134] Table 6

[0135] Half image height 5.42 MIC 5.52 Fno 2 inf wavelength 650:610:555:510:470＝107:503:1000:503:91 TTL 7.1767 inf 7.2411 30cm IR 0.21 FOV 85.00000643 inf 84.6 30cm DISTORTIONOPTICAL 2.40％ inf RI 25.00％ D direction Object distance range 30CM~INF Number of groups 3 AF Itinerary 29UM Upper group and middle group 93UM Middle group and lower group Upper-middle group gap 0.576058652 inf 0.547380335 30cm Middle and lower group gap 0.19 inf 0.283144533 30cm

[0136] In this preferred embodiment of the present invention, the image plane formed by the internal focus lens has a half-image height (ImgH) of 5.42. As an example, the variable object distance is 30 cm-inf (infinity). When the object distance is infinite, the total optical length (TTL) of the optical system of the internal focus lens is 7.1767 mm. When the object distance is 30 cm, the total optical length (TTL) of the internal focus lens is 7.2411 mm. When the object distance is infinite, the maximum field of view (FOV) of the optical projection lens of the internal focus lens is 85.0000064280624 mm; when the object distance is 30 cm, the maximum field of view (FOV) of the optical projection lens of the internal focus lens is 84.6 mm. In this preferred embodiment of the present invention, the travel distance along the optical axis between the upper lens group and the fourth lens 40 (movable lens) is 29 μm; and the travel distance along the optical axis between the lower lens group and the fourth lens 40 (movable lens) is 93 μm. When the object distance is infinite, the gap between the fourth lens 40 and the upper lens group is 0.576058651839191 mm, and the gap between the fourth lens 40 and the lower lens group is 0.19; when the object distance is 30 cm, the gap between the fourth lens 40 and the upper lens group is 0.547380334656721 mm, and the gap between the fourth lens 40 and the lower lens group is 0.283144532700109.

[0137] Figure 6A and 6B The following diagram shows the distortion curves for the inner focus lens according to the second preferred embodiment of the present invention at object distances of inf and 30 cm. It can be seen that the inner focus lens according to the second preferred embodiment of the present invention effectively reduces lens distortion. In particular, when the object distance is infinite, the distortion of the inner focus lens is less than 2.40%. Figure 7A and Figure 7Bshows the astigmatism curves corresponding to the inner focus lens of the second preferred embodiment of the present invention when the object distance is infinite and 30 cm; Figure 8A and Figure 8B The chromatic aberration curves on each axis for the inner focus lens of the second preferred embodiment of the present invention at object distances of infinity and 30 cm are shown. It can be seen that the inner focus lens of the second preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0138] Referring to the accompanying drawings of the present invention 9A to 12B As shown, an internal focus lens according to a third preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has negative focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has positive focal power, and the object side surface 51 of the fifth lens is convex, and the image side surface 52 of the fifth lens 50 is convex; the sixth lens 60 has positive focal power, wherein the object side surface 61 of the sixth lens 60 is concave, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative focal power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M The value of / f is 0.890931007847845; the value of |∑fn| / f is 3.2738202318575; ∑R LnS1 / R LnS2 The value is 2.39693; AFD max The value is 0.307432; the CT1 / TTL value is 0.121166; TTL max -TTL min The value is 0.307432; the TTL / (2*ImgH) value is 0.657226; the SP value is 0.18; the BFL / TTL value is 0.0792877; the fup / fdown value is -0.969469009643951; and the ImageH value is 5.12.

[0139] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0140] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0141] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0142] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=5.8mm; Fno=2; and FOV=85 degrees.

[0143] Table 7 shows the structural parameters of each lens of the inner focus lens according to the third preferred embodiment of the present invention.

[0144] Table 7

[0145]

[0146]

[0147] Table 7 shows detailed structural data for each lens of the inner-focus lens according to the third preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 8 shows aspheric surface data for each lens of the inner-focus lens according to the third preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 7 and 8 of the embodiments and are not further elaborated here.

[0148] Table 8

[0149]

[0150]

[0151] Specifically, in this preferred embodiment of the present invention, the internal focus lens comprises an upper lens group L1 and a lower lens group L2, wherein the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, and the fifth lens 50 constitute the upper lens group L1, and the sixth lens 60 and the seventh lens 70 constitute the lower lens group L2. The lenses of the lower lens group L2 are fixed in position, while the upper lens group L1 is movable as a whole relative to the lower lens group L2. That is, the upper lens group L1 can be driven by the internal focus motor to move along the optical axis. It is understood that when the object distance changes, the internal focus motor drives the upper lens group L1 (the movable lens) to move to maintain the position of the image plane formed by the internal focus lens unchanged.

[0152] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50 can be driven by the inner focus motor to move as a whole along the optical axis to achieve the fixing of the imaging position of the inner focus lens.

[0153] Table 9 shows the basic parameters of the internal focus lens according to the third preferred embodiment of the present invention.

[0154] Table 9

[0155]

[0156]

[0157] In this preferred embodiment of the present invention, the half-image height ImgH value of the image plane formed by the inner focus lens is 5.12. As an example, the variable distance of the object distance is 10cm-inf (infinity), wherein when the object distance is infinity, the total optical length TTL value of the optical system of the inner focus lens is 6.73mm, and when the object distance is 10cm, the total optical length TTL value of the inner focus lens is 7.0374. When the object distance is infinity (inf), the maximum angle of view of the optical projection lens of the inner focus lens is 80°; when the object distance is 10cm, the maximum angle of view of the optical projection lens of the inner focus lens is 78°. In this preferred embodiment of the present invention, the travel distance of the upper lens group L1 along the optical axis direction is 0.307431937mm. When the object distance is infinite, the gap between the lower lens group L2 and the upper lens group L1 is 0.18 mm; when the object distance is 10 cm, the gap between the lower lens group L2 and the upper lens group L1 is 0.487431937 mm.

[0158] Figure 10A and 10B The distortion curves corresponding to the inner focus lens of the third preferred embodiment of the present invention when the object distance is inf and 10 cm are shown. It can be seen that the inner focus lens of the third preferred embodiment of the present invention effectively improves the distortion of the lens. Figure 11A and Figure 11B shows the astigmatism curves corresponding to the inner focus lens of the third preferred embodiment of the present invention when the object distance is infinite and 10 cm; Figure 12A and Figure 12B The chromatic aberration curves on each axis for the inner focus lens of the third preferred embodiment of the present invention at object distances of infinity and 30 cm are shown. It can be seen that the inner focus lens of the third preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0159] Referring to the accompanying drawings of the present invention Figures 13A to 16B As shown, an internal focus lens according to a fourth preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has negative focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has positive focal power, and the object side surface 51 of the fifth lens is convex, and the image side surface 52 of the fifth lens 50 is convex; the sixth lens 60 has positive focal power, wherein the object side surface 61 of the sixth lens 60 is concave, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative focal power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M / f value is 0.885866176; |∑fn| / f value is 7.895225; ∑R LnS1 / R LnS2 The value is 2.72652; AFD max The value is 0.396615; the CT1 / TTL value is 0.11645; TTL max -TTL minThe value is 0.396615; the TTL / (2*ImgH) value is 0.652826; the SP value is 0.191748; the BFL / TTL value is 0.0848515; the fup / fdown value is -0.970083708286766; and the ImageH value is 5.82.

[0160] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0161] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0162] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0163] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=5.8mm; Fno=2; and FOV=85 degrees.

[0164] Table 10 shows the structural parameters of each lens of the inner focus lens according to the fourth preferred embodiment of the present invention.

[0165] Table 10

[0166]

[0167]

[0168] Table 10 shows detailed structural data for each lens of the inner-focus lens according to the fourth preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 11 shows aspheric surface data for each lens of the inner-focus lens according to the fourth preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 10 and 11 of the embodiments and are not further elaborated here.

[0169] Table 11

[0170]

[0171]

[0172] Specifically, in this preferred embodiment of the present invention, the internal focus lens comprises an upper lens group L1 and a lower lens group L2, wherein the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, and the fifth lens 50 constitute the upper lens group L1, and the sixth lens 60 and the seventh lens 70 constitute the lower lens group L2. The lenses of the lower lens group L2 are fixed in position, while the upper lens group L1 is movable as a whole relative to the lower lens group L2. That is, the upper lens group L1 can be driven by the internal focus motor to move along the optical axis. It is understood that when the object distance changes, the internal focus motor drives the upper lens group L1 (the movable lens) to move to maintain the position of the image plane formed by the internal focus lens unchanged.

[0173] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50 can be driven by the inner focus motor to move as a whole along the optical axis, thereby achieving a fixed imaging position of the inner focus lens.

[0174] Table 12 shows the basic parameters of the internal focus lens according to the fourth preferred embodiment of the present invention.

[0175] Table 12

[0176]

[0177] In this preferred embodiment of the present invention, the image plane formed by the inner focus lens has a half-image height (ImgH) of 5.82084578200054. As an example, the variable object distance is 10 cm-inf (infinity). When the object distance is infinite, the total optical length (TTL) of the optical system of the inner focus lens is 7.52 mm. When the object distance is infinite (inf), the maximum viewing angle (FOV) of the optical projection lens of the inner focus lens is 80°. In this preferred embodiment of the present invention, the travel distance of the upper lens group L1 along the optical axis is 0.397183 mm. When the object distance is infinite, the gap between the lower lens group L2 and the upper lens group L1 is 0.232654329754316 mm; when the object distance is 10 cm, the gap between the lower lens group L2 and the upper lens group L1 is 0.629837556671249 mm.

[0178] Figure 14A and 14BThe distortion curves corresponding to the inner focus lens of the fourth preferred embodiment of the present invention when the object distance is inf and 10 cm are shown. It can be seen that the inner focus lens of the fourth preferred embodiment of the present invention effectively improves the distortion of the lens. Figure 15A and Figure 15B 4 shows the astigmatism curves corresponding to the inner focus lens of the fourth preferred embodiment of the present invention when the object distance is infinite and 10 cm; Figure 16A and Figure 16B The chromatic aberration curves on each axis for the inner focus lens of the fourth preferred embodiment of the present invention at object distances of infinity and 10 cm are shown. It can be seen that the inner focus lens of the fourth preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0179] Referring to the accompanying drawings of the present invention 17A to 20B As shown, an internal focus lens according to the fifth preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has negative focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has positive focal power, and the object side surface 51 of the fifth lens is convex, and the image side surface 52 of the fifth lens 50 is concave; the sixth lens 60 has positive focal power, wherein the object side surface 61 of the sixth lens 60 is concave, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative focal power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M / f value is 0.889264706; |∑fn| / f value is 8.50639852941176; ∑R LnS1 / R LnS2 The value is 3.00093; AFD max The value is 0.397183; the CT1 / TTL value is 0.0968783; TTL max -TTL minThe value is 0.397183; the TTL / (2*ImgH) value is 0.645954; the SP value is 0.232654; the BFL / TTL value is 0.0914541; the fup / fdown value is -0.973466713459179; and the ImageH value is 5.82.

[0180] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0181] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0182] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0183] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=5.8mm; Fno=2; and FOV=85 degrees.

[0184] Table 13 shows the structural parameters of each lens of the inner focus lens according to the fifth preferred embodiment of the present invention.

[0185] Table 13

[0186]

[0187]

[0188] Table 13 shows detailed structural data for each lens of the inner-focus lens according to the fifth preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 14 shows aspheric surface data for each lens of the inner-focus lens according to the fifth preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 13 and 14 of the embodiments and are not further elaborated here.

[0189] Table 14

[0190]

[0191]

[0192] Specifically, in this preferred embodiment of the present invention, the internal focus lens comprises an upper lens group L1 and a lower lens group L2, wherein the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, and the fifth lens 50 constitute the upper lens group L1, and the sixth lens 60 and the seventh lens 70 constitute the lower lens group L2. The lenses of the lower lens group L2 are fixed in position, while the upper lens group L1 is movable as a whole relative to the lower lens group L2. That is, the upper lens group L1 can be driven by the internal focus motor to move along the optical axis. It is understood that when the object distance changes, the internal focus motor drives the upper lens group L1 (the movable lens) to move to maintain the position of the image plane formed by the internal focus lens unchanged.

[0193] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50 can be driven by the inner focus motor to move as a whole along the optical axis, thereby achieving a fixed imaging position of the inner focus lens.

[0194] Table 15 shows the basic parameters of the internal focus lens according to the fifth preferred embodiment of the present invention.

[0195] Table 15

[0196]

[0197]

[0198] In this preferred embodiment of the present invention, the image plane formed by the inner focus lens has a half-image height (ImgH) of 5.82084578200054. As an example, the variable object distance is 10 cm-inf (infinity). When the object distance is infinite, the total optical length (TTL) of the optical system of the inner focus lens is 7.52 mm. When the object distance is infinite (inf), the maximum viewing angle (FOV) of the optical projection lens of the inner focus lens is 80°. In this preferred embodiment of the present invention, the travel distance of the upper lens group L1 along the optical axis is 0.397183 mm. When the object distance is infinite, the gap between the lower lens group L2 and the upper lens group L1 is 0.232654329754316 mm; when the object distance is 10 cm, the gap between the lower lens group L2 and the upper lens group L1 is 0.629837556671249 mm.

[0199] Figure 18A and 18B The distortion curves corresponding to the inner focus lens of the fifth preferred embodiment of the present invention when the object distance is inf and 10 cm are shown. It can be seen that the inner focus lens of the fifth preferred embodiment of the present invention effectively improves the distortion of the lens. Figure 19A and Figure 19B 4 shows the astigmatism curves corresponding to the inner focus lens of the fifth preferred embodiment of the present invention when the object distance is infinite and 10 cm; Figure 20A and Figure 20B The chromatic aberration curves on each axis for the inner focus lens of the fifth preferred embodiment of the present invention at object distances of infinity and 10 cm are shown. It can be seen that the inner focus lens of the fifth preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0200] Referring to the accompanying drawings of the present invention Figures 21A to 24B As shown, an internal focus lens according to the sixth preferred embodiment of the present invention is explained in the following description. In this preferred embodiment of the present invention, the first lens 10 has positive focal power, and the object-side surface 11 of the first lens is convex, and the image-side surface 12 of the first lens 10 is concave; the second lens 20 has negative focal power, and the object-side surface 21 of the second lens is convex, and the image-side surface 22 of the second lens 20 is concave; the third lens 30 has positive focal power, and the object-side surface 31 of the third lens is convex, and the image-side surface 32 of the third lens 30 is concave; the fourth lens 40 has negative focal power, and the fourth lens The object side surface 41 of the lens is concave, and the image side surface 42 of the fourth lens 40 is convex; the fifth lens 50 has positive focal power, and the object side surface 51 of the fifth lens is convex, and the image side surface 52 of the fifth lens 50 is concave; the sixth lens 60 has positive focal power, wherein the object side surface 61 of the sixth lens 60 is concave, and the image side surface 62 of the sixth lens 60 is convex; the third lens 70 has negative focal power, wherein the object side surface 71 of the seventh lens 70 is concave, and the image side surface 72 of the seventh lens 70 is concave. Each lens of the inner focus lens meets the above conditional formula, and in this preferred embodiment of the present invention, it is preferably: f M / f value is 0.945422222; |∑fn| / f value is 2.75903333333333; ∑R LnS1 / R LnS2 The value is 3.14458; AFD max The value is 0.185924; the CT1 / TTL value is 0.114148; TTL max -TTL minThe value is 0.185924; the TTL / (2*ImgH) value is 0.662084; the SP value is 0.34777; the BFL / TTL value is 0.0646081; the fup / fdown value is -0.850344283101646; and the ImageH value is 4.2.

[0201] In each embodiment consistent with the above-mentioned implementation manner, the aspheric curve equation of each lens of the inner focus lens is expressed as follows:

[0202] X(Y)=(Y 2 / R) / (1+sqrt(1-(1+k)×(Y / R) 2 ))+∑(A i )×(Y i )

[0203] Where: X is the relative distance between the point on the aspheric surface and the intersection of the point tangent to the optical axis of the aspheric surface, which is Y away from the optical axis; Y is the perpendicular distance between the point on the aspheric curve and the optical axis; R is the radius of curvature; k is the cone coefficient; Ai is the i-th order aspheric coefficient.

[0204] In this preferred embodiment of the present invention, the focal length of the optical projection lens is f, the aperture value (f-number) of the optical projection lens is Fno, and the maximum viewing angle of the optical projection lens is FOV, whose values ​​are as follows: f=5.8mm; Fno=2; and FOV=85 degrees.

[0205] Table 16 shows the structural parameters of each lens of the internal focus lens according to the sixth preferred embodiment of the present invention.

[0206] Table 16

[0207]

[0208]

[0209] Table 16 shows detailed structural data for each lens of the inner-focus lens according to the sixth preferred embodiment of the present invention, with the units of curvature radius, thickness, and focal length expressed in mm. Table 17 shows aspheric surface data for each lens of the inner-focus lens according to the sixth preferred embodiment of the present invention, where K represents the conic coefficient in the aspheric curve equation, and A4-A20 represent the 4th-20th order aspheric coefficients of each surface. Furthermore, the tables in the following embodiments correspond to the schematic diagrams and aberration curves of each embodiment. The definitions of the data in the tables are the same as those in Tables 16 and 17 of the embodiments and are not further elaborated here.

[0210] Table 17

[0211]

[0212]

[0213] Specifically, in this preferred embodiment of the present invention, the internal focus lens comprises an upper lens group L1 and a lower lens group L2, wherein the first lens 10, the second lens 20, the third lens 30, the fourth lens 40, and the fifth lens 50 constitute the upper lens group L1, and the sixth lens 60 and the seventh lens 70 constitute the lower lens group L2. The lenses of the lower lens group L2 are fixed in position, while the upper lens group L1 is movable as a whole relative to the lower lens group L2. That is, the upper lens group L1 can be driven by the internal focus motor to move along the optical axis. It is understood that when the object distance changes, the internal focus motor drives the upper lens group L1 (the movable lens) to move to maintain the position of the image plane formed by the internal focus lens unchanged.

[0214] Simply put, in this preferred embodiment of the present invention, the upper lens group consisting of the first lens 10, the second lens 20, the third lens 30, the fourth lens 40 and the fifth lens 50 can be driven by the inner focus motor to move as a whole along the optical axis, thereby achieving a fixed imaging position of the inner focus lens.

[0215] Table 18 shows the basic parameters of the internal focus lens according to the sixth preferred embodiment of the present invention.

[0216] Table 18

[0217]

[0218] In this preferred embodiment of the present invention, the half-image height (ImgH) of the image plane formed by the inner-focus lens is 4.20591839714915. As an example, the variable object distance is 10 cm-inf (infinity). When the object distance is infinite, the total optical length (TTL) of the optical system of the inner-focus lens is 5.3232 mm. When the object distance is infinite (inf), the maximum viewing angle (FOV) of the optical projection lens of the inner-focus lens is 85°. In this preferred embodiment of the present invention, the travel distance of the upper lens group L1 along the optical axis is 0.185924327 mm. When the object distance is infinite, the gap between the lower lens group L2 and the upper lens group L1 is 0.34777018569938 mm; when the object distance is 10 cm, the gap between the lower lens group L2 and the upper lens group L1 is 0.533694512735 mm.

[0219] Figure 22A and 22BThe distortion curves corresponding to the inner focus lens of the sixth preferred embodiment of the present invention when the object distance is inf and 10 cm are shown. It can be seen that the inner focus lens of the sixth preferred embodiment of the present invention effectively improves the distortion of the lens. Figure 23A and Figure 23B 4 shows the astigmatism curves corresponding to the internal focus lens of the sixth preferred embodiment of the present invention when the object distance is infinite and 10 cm; Figure 24A and Figure 24B The chromatic aberration curves on each axis for the inner focus lens of the sixth preferred embodiment of the present invention at object distances of infinity and 10 cm are shown. It can be seen that the inner focus lens of the sixth preferred embodiment of the present invention effectively improves the astigmatism and chromatic aberration performance of the lens, which is beneficial for improving the imaging quality of the camera module.

[0220] Referring to the accompanying drawings of the present invention Figure 25 As shown, a camera module according to another aspect of the present invention is explained in the following description. The camera module includes an internal focus lens 300 as described above, a photosensitive component 400 and at least one internal focus motor 500, wherein the internal focus lens 300 is arranged along a photosensitive path of the photosensitive component 400, and the internal focus motor 500 is connected to at least one movable lens of the internal focus lens 300, and the movable lens is driven by the internal focus motor 300 so that when the object distance photographed by the camera module changes, the imaging position of the internal focus lens 300 remains unchanged. It is worth mentioning that in this preferred embodiment of the present invention, the internal focus motor 500 is the internal focus motor in the above-mentioned preferred embodiment.

[0221] Those skilled in the art will appreciate that the embodiments of the present invention described above and shown in the accompanying drawings are intended to be illustrative only and are not intended to limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and illustrated in the embodiments. Any variations or modifications may be made to the embodiments of the present invention without departing from the principles described.

Claims

1. An internal focus lens, characterized in that, Comprising: A first lens with a positive focal length; A second lens with a negative focal length; A third lens with a positive focal length; A fourth lens with a negative focal length; A fifth lens with a positive focal length; A sixth lens with a positive focal length; and A seventh lens with a negative focal length, wherein the first lens, the second lens, the third lens, the fourth lens, and the fifth lens form the upper group lens set, and the sixth lens and the seventh lens form the lower group lens set. The upper group lens set is a movable lens group, and focusing is achieved by moving the upper group lens set. During the focusing process, the lower group lens set remains in place. Let the thickness of the nth lens on the optical axis be CTn, the total optical length of the optical system of the internal focusing lens be TTL, and the semi-image height of the image plane be ImgeH. The following conditions are satisfied: 0.05 < CT1 / TTL < 0.15; 0.6 < TTL object distance / (2 * ImgeH) < 0.

8.

2. The internal focusing lens according to claim 1, wherein the seventh lens has the shape of an M-type lens.

3. The internal focusing lens according to claim 1, wherein the focal length of the internal focusing lens is f, the focal length of the movable lens group is fM, the focal length of the nth lens is fn, the curvature radius of the nth lens near the object side is RLnS1, the curvature radius of the nth lens near the object side is RLnS2, and the maximum stroke of the movable lens group is AFD. The following conditions are satisfied: 0.8 < fM / f < 2.9; 2.76 < |∑fn| / f < 8.5; 2.40 < ∑RLnS1 / RLnS2 < 3.14; 0.09 < AFD < 0.5, and the upper group lens set and / or the lower group lens set provides positive optical power.

4. The internal focusing lens according to claim 1, wherein the object side surface of the first lens is convex, the image side surface of the first lens is concave, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, the object side surface of the fourth lens is concave, the image side surface of the fourth lens is convex, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is concave, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is convex, the object side surface of the seventh lens is concave, and the image side surface of the seventh lens is concave.

5. The internal focusing lens according to claim 4, wherein the aspheric curve equations of each of the lenses of the internal focusing lens are expressed as follows: in: X is the relative distance of a point on the aspheric surface at a distance Y from the optical axis to the tangent plane at the intersection of the aspheric surface and the optical axis; Y is the perpendicular distance of a point on the aspheric curve from the optical axis; R is the radius of curvature; k is the conic coefficient; Ai is the i-th order aspheric coefficient.

6. A camera module, characterized in that: Comprising: An internal focusing lens; A photosensitive component, wherein the internal focusing lens is disposed on the photosensitive component; And At least one internal focusing motor, wherein the internal focusing lens comprises: A first lens with a positive focal length; A second lens with a negative focal length; A third lens with a positive focal length; A fourth lens with a negative focal length; A fifth lens with a positive focal length; A sixth lens with a positive focal length; and A seventh lens with a negative focal length, wherein the first lens, the second lens, the third lens, the fourth lens, and the fifth lens form the upper group lens set, and the sixth lens and the seventh lens form the lower group lens set. The upper group lens set is a movable lens group, and focusing is achieved by moving the upper group lens set. During the focusing process, the lower group lens set remains in place. Let the thickness of the nth lens on the optical axis be CTn, the total optical length of the optical system of the internal focusing lens be TTL, and the semi-image height of the image plane be ImgeH. The following conditions are satisfied: 0.05 < CT1 / TTL < 0.15; 0.6 < TTL object distance / (2 * ImgeH) < 0.

8.

7. The imaging module according to claim 6, wherein the seventh lens has the shape of an M-type lens.

8. The imaging module according to claim 7, wherein the focal length of the internal focusing lens is f, the focal length of the movable lens group is fM, the focal length of the nth lens is fn, the curvature radius of the nth lens near the object side is RlnS1, the curvature radius of the nth lens near the object side is RlnS2, and the maximum stroke of the movable lens group is AFD. The following conditions are satisfied: 0.8 < fM / f < 2.9; 2.76 < |∑fn| / f < 8.5; 2.40 < ∑RlnS1 / RlnS2 < 3.14; 0.09 < AFD < 0.5, and the upper group lens set and / or the lower group lens set provides positive optical power.

9. The imaging module according to claim 6, wherein the object side surface of the first lens is convex, the image side surface of the first lens is concave, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, the object side surface of the fourth lens is concave, the image side surface of the fourth lens is convex, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is concave, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is convex, the object side surface of the seventh lens is concave, and the image side surface of the seventh lens is concave.

10. The imaging module according to claim 9, wherein the aspheric curve equation of each lens of the internal focusing lens is expressed as follows: in: X is the relative distance of a point on the aspheric surface at a distance Y from the optical axis to the tangent plane at the intersection of the aspheric surface and the optical axis; Y is the perpendicular distance of a point on the aspheric curve from the optical axis; R is the radius of curvature; k is the conic coefficient; Ai is the ith-order aspheric coefficient.

Images