Optical lens, camera module, and electronic device

Abstract

An optical lens (102), a camera module (10), and an electronic device (1). The optical lens (102) comprises a first lens group (G1), a second lens group (G2), and a third lens group (G3). The first lens group (G1), the second lens group (G2), and the third lens group (G3) are sequentially arranged from an object side to an image side of the optical lens (102). The first lens group (G1) and the second lens group (G2) both have positive focal power, and the third lens group (G3) has negative focal power. The first lens group (G1), the second lens group (G2), and the third lens group (G3) are all used for moving along the optical axis (O) of the optical lens (102) and achieving zooming of the optical lens (102). In the process of the optical lens (102) switching from a first working state to a second working state, the first lens group (G1) and the third lens group (G3) both move towards the object side. The second lens group (G2) is configured to move towards the object side along the optical axis (O) once zooming of the optical lens (102) has been completed, so that focusing of the optical lens (102) is achieved, and the total track length of the optical lens (102) is reduced.

Description

Optical lenses, camera modules and electronic devices

[0001] This application claims priority to Chinese Patent Application No. 202411465269.7, filed on October 18, 2024, with the Chinese National Intellectual Property Administration, entitled "Optical Lens, Camera Module and Electronic Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of photography, and more particularly to an optical lens, a camera module, and an electronic device. Background Technology

[0003] To achieve optical zoom in mobile phone cameras, one existing solution is to place a zoom lens inside the camera, switching focal lengths by moving the lens elements within the zoom lens. However, the total track length (TTL) of the zoom lens in conventional solutions is relatively large, requiring the phone to be quite thick to meet the zoom requirements of the lens, which is not conducive to reducing the thickness of the phone. Summary of the Invention

[0004] This application provides an optical lens, a camera module, and an electronic device, which can reduce the TTL of the optical lens and facilitate the thinning of the electronic device.

[0005] In a first aspect, embodiments of this application provide an optical lens, including a first lens group, a second lens group, and a third lens group, arranged sequentially from the object side to the image side of the optical lens. The first and second lens groups each have positive optical power, while the third lens group has negative optical power. The first, second, and third lens groups are all used to move along the optical axis of the optical lens to achieve zoom, wherein: during the process of the optical lens changing from a short focal length to a long focal length, both the first and third lens groups move towards the object side; during the process of the optical lens changing from a first operating state to a second operating state, both the first and third lens groups move towards the object side; during the process of the optical lens changing from a second operating state to a first operating state, both the first and third lens groups move towards the image side; wherein the effective focal length of the optical lens in the first operating state is less than the effective focal length in the second operating state; the second lens group is used to move along the optical axis towards the object side after the optical lens has completed zooming to achieve focusing.

[0006] In this embodiment, by arranging lens groups with positive optical power, positive optical power, and negative optical power sequentially from the object side to the object side, a reverse telephoto architecture can be formed, making the total optical length (TTL) of the optical lens less than its effective focal length (EFFL). Since the EFFL of an optical lens is related to its specifications, by forming a reverse telephoto architecture, the TTL can be limited to a range less than the EFFL. This helps to reduce the TTL, allowing electronic devices to meet the zoom requirements of the optical lens without requiring a large thickness, thus facilitating the thinning of electronic devices.

[0007] In one implementation, during the zooming process of the optical lens, the displacement of the third lens group along the optical axis is greater than the displacement of the first lens group along the optical axis. This implementation, by making the displacement of the third lens group larger, not only allows the optical lens to have a larger zoom ratio, but also avoids excessively high TTL values ​​for the optical lens.

[0008] In one implementation, the total optical length (TTL) of the optical lens at its maximum focal length is... max Total optical length (TTL) at the smallest focal length min Effective focal length (EFFL) at maximum focal length max And the effective focal length EFFL at the smallest focal length min Satisfying the following relationship: TTL max -TTL min ≤EFFL max -EFFL min By limiting the TTL variation range to the above-mentioned range, excessive TTL variation can prevent the first lens group from having an excessively large stroke, which helps to simplify the optical lens drive mechanism and saves the space occupied by the drive mechanism (if the stroke is too large, the drive mechanism needs to be more complex and will also occupy more space).

[0009] In one implementation, the total optical length (TTL) of the optical lens at its maximum focal length is... max Total optical length (TTL) at the smallest focal length min Effective focal length (EFFL) at maximum focal length max And the effective focal length EFFL at the smallest focal length min Satisfying the following relationship: TTL max / TTL min ≤EFFL max / EFFL min By limiting the TTL variation range to the above-mentioned range, excessive TTL variation can prevent the first lens group from having an excessively large stroke, which helps to simplify the optical lens drive mechanism and saves the space occupied by the drive mechanism (if the stroke is too large, the drive mechanism needs to be more complex and will also occupy more space).

[0010] In one implementation, during the transition of the optical lens from a first operating state to a second operating state, the second lens group is moved toward the object side. By moving the second lens group toward the object side during zooming, the zoom ratio can be increased.

[0011] In one implementation, the first lens group is also used to move along the optical axis toward the object side after the optical lens has zoomed, so that the optical lens can focus. The displacement of the first lens group and the second lens group is the same. By moving the first and second lens groups synchronously after zooming, focusing can be achieved, and design freedom can be increased to meet certain product design requirements.

[0012] In one implementation, the optical lens has a retracted state, where its total optical length TTL0 is less than its total optical length TTL1 in the first operating state. This implementation achieves the "extension and contraction" of the optical lens through the movement of the lens group within the lens, thus enabling the optical lens to have both a retracted and an operating state. This design can be applied to height-adjustable camera modules, utilizing the external space of the electronic device to meet the lens travel requirements without increasing the thickness of the electronic device, thus balancing image quality and thinness.

[0013] In one implementation, the effective focal length EFFL2 of the second lens group and the effective focal length EFFL of the optical lens at its maximum focal length are... max and the effective focal length (EFFL) at the smallest focal length min It satisfies the following relationship: 0.3*EFFL max ≤EFFL2≤EFFL max 0.3*EFFL min ≤EFFL2≤EFFL min Or, 0.3*EFFL max ≤EFFL min 0.3*EFFL max ≤EFFL2≤EFFL min .

[0014] Since the optical power of the second lens group G2 is inversely proportional to EFFL2, the range of the optical power of the second lens group G2 can be limited by limiting the range of EFFL2. By limiting the optical power of the second lens group within the reasonable range mentioned above, good image quality and high motor accuracy can be guaranteed (excessive optical power will cause the second lens group to produce too many aberrations, making the image quality unsatisfactory during focusing; while insufficient optical power will result in an excessively long focusing stroke, thereby reducing the motor accuracy (focusing stroke and accuracy are usually inversely proportional)).

[0015] In one implementation, the effective focal length (EFFL) of the optical lens at its maximum focal length is... max With the effective focal length EFFL at the smallest focal length min Satisfy the following relationship: EFFL max / EFFL min ≥1.3. EFFL max / EFFL min This refers to the zoom ratio of the optical lens. By limiting the zoom ratio of the optical lens to this range, a wider field of view can be achieved, thus improving image quality.

[0016] In one implementation, 1.3 ≤ EFFL max / EFFL min ≤(1 / 0.3). This implementation method ensures that the zoom ratio is within a suitable range to meet product requirements.

[0017] In one implementation, the field of view (FOV1) of the optical lens in the first operating state is ≤50°. In this implementation, the optical lens can be a telephoto lens, and a reverse telephoto architecture can be implemented based on the telephoto lens, thereby reducing TTL. It can also enable optical zoom by the telephoto lens.

[0018] In one implementation, the effective focal length EFFL1 of the first lens group is greater than or equal to the effective focal length EFFL of the optical lens at its maximum focal length. max This implementation method can improve the zoom ratio of optical lenses.

[0019] In one implementation, the first lens group includes at least one lens, and / or the second lens group includes at least two lenses, and / or the third lens group includes at least two lenses. By setting the number of lenses in each lens group, better imaging results can be achieved, for example, aberration correction can be performed.

[0020] Secondly, embodiments of this application provide a camera module, including an image sensor and an optical lens, wherein the image sensor is located on the image side of the optical lens. The camera module of this application embodiment is small in size, occupies less internal space in the electronic device, and is beneficial for achieving thinner electronic devices.

[0021] In one implementation, the camera module is installed in an electronic device with its optical axis perpendicular to the device's display screen. This camera module can be a vertical camera module.

[0022] In one implementation, the camera module includes a module cover plate disposed on the object side of the optical lens and used to cover the opening in the electronic device. The module cover plate is also used to move along the optical axis of the optical lens. By setting a liftable module cover plate, the external space of the electronic device can be used to meet the travel requirements of the optical lens without increasing the thickness of the electronic device, thus balancing image quality and thinness.

[0023] In one implementation, the camera module also includes a variable aperture located on the light-incident side of the image sensor. The optical lens of this implementation can be used in conjunction with the variable aperture to achieve closer-range photography, while simultaneously improving the depth of field of the entire image in close-range photography.

[0024] In one implementation, the variable stop is located on the object side of the optical lens. By placing the variable stop forward, the TTL of the optical lens is not increased because the thickness of the variable stop is not included in the TTL of the optical lens.

[0025] Thirdly, embodiments of this application provide an electronic device, including a main body and a camera module, with the camera module disposed on the main body. The camera module of this application embodiment is small in size, occupying less internal space in the electronic device, thus allowing the electronic device to have a smaller overall size. Attached Figure Description

[0026] Figure 1 is a schematic diagram of the planar structure of an electronic device according to an embodiment of this application;

[0027] Figure 2 illustrates the schematic framework structure and working principle of a camera module according to one embodiment of this application;

[0028] Figure 3 is a side view of the optical lens and image sensor in a retracted state in one embodiment.

[0029] Figure 4 is a schematic diagram of the anti-photograph structure formed by the first lens group G1, the second lens group G2, and the third lens group G3.

[0030] Figure 5 illustrates the structure and positional relationship of the optical lens in Figure 3 in the first working state;

[0031] Figure 6 illustrates the structure and positional relationship of the optical lens in Figure 3 in the second working state;

[0032] Figure 7 illustrates the structure and positional relationship of the optical lens in Figure 3 in the third working state;

[0033] Figure 8 illustrates the structure and positional relationship of the optical lens in Figure 3 in the fourth working state;

[0034] Figure 9 illustrates the structure of the optical lens in Figure 3 in its fifth working state;

[0035] Figure 10 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 5.

[0036] Figure 11 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 6.

[0037] Figure 12 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 7.

[0038] Figure 13 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 8.

[0039] Figure 14 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 9.

[0040] Figure 15 illustrates the structure of the optical lens in the first working state in another embodiment;

[0041] Figure 16 illustrates the structure of the optical lens in a third operating state in another embodiment;

[0042] Figure 17 illustrates the structure of the optical lens in a fourth operating state in another embodiment;

[0043] Figure 18 illustrates the structure of the optical lens in the fifth operating state in another embodiment;

[0044] Figure 19 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 15.

[0045] Figure 20 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 16.

[0046] Figure 21 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 17.

[0047] Figure 22 illustrates the modulation transfer function contrast transfer curve of the optical lens in Figure 18. Detailed Implementation

[0048] For ease of understanding, the English abbreviations and related technical terms used in the embodiments of this application will be explained and described below.

[0049] Focal power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam; it characterizes the ability of an optical system to deflect light rays.

[0050] A lens or lens group with positive optical power, having a positive focal length, and having the effect of converging light.

[0051] A lens or lens group with negative optical power has a negative focal length and has the effect of diverging light.

[0052] Focal length, also known as focal length, is a measure of the convergence or divergence of light in an optical system. It refers to the perpendicular distance from the optical center of a lens or lens group to the focal plane when a distant object is projected into a sharp image. From a practical perspective, it can be understood as the distance from the center of the lens to the focal plane when the object is at infinity. For fixed-focus lenses, the position of their optical center remains constant; for optical lenses, changes in the optical center result in changes in the focal length.

[0053] The object side is defined by the lens; the side where the object is located is called the object side, and the surface of the lens closest to the object side is called the object side surface.

[0054] The image side is the side on which the image of the object is located, with the lens as the boundary. The surface of the lens closest to the image side is called the image side surface.

[0055] An aperture diaphragm is a device used to control the amount of light passing through the lens and entering the sensor inside the camera body; it is usually located inside the lens.

[0056] Aperture value, also known as F-number (Fno), is a relative value derived from the lens's focal length and entrance pupil diameter (the reciprocal of the relative aperture). A smaller aperture value allows more light to enter the lens in the same unit of time. A larger aperture value results in a shallower depth of field, blurring the background and creating an effect similar to that of an optical lens.

[0057] Total track length (TTL) refers to the total length from the surface of the lens closest to the object to the imaging plane. TTL is a major factor in determining the height of the camera.

[0058] The imaging plane is located on the image side of all lenses in an optical lens, and is the surface on which light rays pass through each lens in the optical lens in sequence to form an image.

[0059] The optical axis is a perpendicular axis passing through the center of a lens. The lens optical axis is the axis passing through the centers of all the individual lenses in the lens. When light rays parallel to the optical axis enter a convex lens, an ideal convex lens should cause all light rays to converge at a single point behind the lens; this point of convergence is the focal point. The direction of the optical axis is the direction in which the optical axis extends.

[0060] The focal point is the point where parallel light rays converge after being refracted by a lens or lens group.

[0061] The image-side focal plane, also known as the back focal plane or the second focal plane, is a plane that passes through the image-side focal point (also known as the back focal point or the second focal point) and is perpendicular to the optical axis of the system.

[0062] The Abbe number, also known as the dispersion coefficient, is the ratio of the difference in refractive index of an optical material at different wavelengths, representing the degree of dispersion of the material.

[0063] The field of view (FOV) in optical instruments is the angle between the two edges of the lens, representing the maximum range through which the image of the target object can pass through the lens. The size of the FOV determines the field of view of the optical instrument; a larger FOV results in a wider field of view but a lower optical magnification.

[0064] Half-image height (ImgH) represents half the diagonal length of the effective pixel area on the image sensor, which is also the image height of the imaging surface.

[0065] The chief ray angle (CRA) is the maximum angle between the light ray originating from the center of the optical lens, passing through the optical lens, and reaching the sensor surface, and the normal to the sensor surface.

[0066] Aberrations are the properties of an ideal optical system in the paraxial region. Paraxial rays emitted from a point on an object intersect the image plane at a single point (i.e., the paraxial image point). However, in reality, rays passing through different apertures of a lens rarely intersect perfectly at a single point. Instead, they deviate from the position of the paraxial image point. These differences are collectively referred to as aberrations.

[0067] Axial spherical aberration, also known as longitudinal chromatic aberration, positional chromatic aberration, or axial aberration, occurs when a beam of light parallel to the optical axis converges at different positions after passing through a lens. This aberration is called positional chromatic aberration or axial chromatic aberration. This is because the lens images different wavelengths of light at different positions, causing the image-side focal planes of different colors of light to not coincide, resulting in the dispersion of polychromatic light.

[0068] Distortion, also known as image distortion, refers to the degree of distortion in the image formed by an optical system relative to the object itself. Distortion occurs due to the spherical aberration of the aperture. The height of the intersection point between the principal ray from different fields of view and the Gaussian image plane is not equal to the ideal image height; this difference is the distortion. Therefore, distortion only changes the imaging position of an off-axis object point on the ideal plane, causing a distortion in the image shape, but it does not affect the image's sharpness.

[0069] Astigmatism occurs because the object point is not on the optical axis of the optical system, and the emitted beam of light has an angle with the optical axis. After refraction by a lens, the convergence points of the meridional and sagittal beams are not at the same point. That is, the beam cannot be focused on a single point, resulting in an unclear image, hence astigmatism. The meridional and sagittal beams are the names of beams in two perpendicular planes within a rotationally symmetric optical system.

[0070] The meridional plane is the plane formed by the principal ray (principal beam) of an object point outside the optical axis and the optical axis.

[0071] The sagittal surface is the plane that passes through the principal ray (principal beam) of an object point outside the optical axis and is perpendicular to the meridional plane.

[0072] Field curvature refers to the difference in optical axis between the position of the sharpest image point after rays from the off-center field of view pass through an optical lens assembly and the position of the sharpest image point in the central field of view. When a lens has field curvature, the intersection of the entire beam does not coincide with the ideal image point. Although a sharp image point can be obtained at each specific point, the entire image plane is a curved surface.

[0073] This application provides an electronic device, including but not limited to mobile phones (candybar phones or foldable phones), tablet computers, laptops, in-vehicle devices, wearable devices, augmented reality (AR) glasses, AR helmets, virtual reality (VR) glasses, VR helmets, laptop computers, personal digital assistants (PDAs), or cameras and other devices with camera functions.

[0074] As shown in Figure 1, for ease of description, the width direction of electronic device 1 can be defined as the X-axis, the length direction as the Y-axis, and the thickness direction as the Z-axis. It is understood that the coordinate system of electronic device 1 can be flexibly set according to specific practical needs and is not limited to those described above.

[0075] As shown in Figures 1 and 2, the electronic device 1 may include a camera module 10, a housing 20, and a display screen 30, etc. It is understood that the figures in this embodiment only schematically show some components of the electronic device 1, and the actual structure, size, position, and quantity of these components are not limited by the figures shown. In this embodiment, the part of the electronic device 1 other than the camera module 10 can be referred to as the main body. It is readily understood that the main body includes the housing 20 and the display screen 30, etc., and the camera module 10 is installed in the main body.

[0076] As shown in Figures 1 and 2, schematically, the housing 20 may include a first housing 201 and a second housing 202. The first housing 201 may be, for example, a rear housing (hereinafter referred to as rear housing 201), and the second housing 202 may be, for example, a mid-frame (hereinafter referred to as mid-frame 202). The rear housing 201 and the display screen 30 may be respectively connected to the two sides of the mid-frame 202. The rear housing 201 and the mid-frame 202 can enclose the internal space of the electronic device 1. Various devices, such as batteries, receivers, and microphones, can be arranged inside the electronic device 1.

[0077] The display screen 30 shown in Figure 2 is merely an illustration and does not limit the actual structure and installation method of the display screen 30. The display screen 30 of the housing 20 can be a flat screen or a curved screen. When the electronic device 1 is some other type of device, the electronic device 1 may not include the display screen 30.

[0078] As shown in Figures 1 and 2, an opening 20a can be formed on the housing 20, the opening 20a connecting the inner and outer spaces of the housing 20, or in other words, connecting the inner and outer spaces of the electronic device 1. In one embodiment, the opening 20a can be provided on the rear housing 201. In another embodiment, the opening 20a can be provided on the display screen 30, or simultaneously on the rear housing 201 and the display screen 30.

[0079] Figures 1 and 2 show a camera module 10 of electronic device 1. This is merely illustrative and does not limit the number of camera modules 10. Electronic device 1 may also have multiple camera modules 10 as needed.

[0080] In this embodiment, the camera module 10 can be a rear camera module that collects light from the rear cover 201. Alternatively, the camera module 10 can be a front camera module that collects light from the display screen 30.

[0081] In this embodiment, the camera module 10 can be a regular camera module, and the optical axis of the camera module 10 is the Z-axis direction.

[0082] The camera module 10 may include an optical lens and an image sensor. The optical lens may include multiple lenses and is used to receive and process ambient light. The optical lens will be described in detail later. The image sensor is located on the image side of the optical lens. Ambient light passing through the optical lens can be projected onto the image sensor to form an image. In one embodiment, the camera module 10 may also include an aperture stop, used to control the amount of light entering the camera. This aperture stop may include, but is not limited to, a variable aperture stop. The position of the aperture stop can be determined as needed, including but not limited to being located on the object side of the optical lens (aperture stop in front) or between the lenses in the optical lens (aperture stop in the center). As shown in Figures 1 and 2, in one embodiment, the camera module 10 may include a module cover plate 101. The module cover plate 101 is exposed, and the user can see the module cover plate 101 from the outside of the electronic device 1. Ambient light passes through the module cover plate 101 and enters the optical lens. In the initial state, the module cover plate 101 can be housed within and cover the opening 20a. For example, the camera module 10 can be a rear-facing camera module, with the module cover 101 housed within an opening 20a on the rear housing 201. The light-incident side of the camera module 10 faces away from the display surface 30a of the display screen 30, where the display surface 30a is the surface on the display screen 30 that displays images. If the camera module 10 is a front-facing camera module, the module cover 101 is housed within the opening 20a on the display screen 30. It is understood that the electronic device 1 can also include a camera module 10 that is both a rear-facing and a front-facing camera module.

[0083] In this embodiment, the module cover 101 can move along the normal direction of the display screen 30 of the electronic device 1, for example, along the Z direction in FIG2. Referring to FIG2, in one embodiment, the module cover 101 can rise along the Z direction and disengage from the opening 20a to protrude from the rear shell 201. The module cover 101 can also descend along the Z direction and fall back into the opening 20a. The module cover 101 can be raised and lowered under the drive of a driving device (e.g., a motor, transmission mechanism, etc.), which can be part of the camera module 10 or independent of the camera module 10.

[0084] In this embodiment, when the camera module 10 is in working mode, some lenses in the optical lens can move along the optical axis of the optical lens (e.g., the Z-axis in Figure 2) to enable the camera module 10 to zoom. Referring to Figure 2, when the module cover plate 101 rises, the lenses have space to move upwards, enabling long-stroke autofocus (AF) movement, achieving multi-focal length shooting, improving focusing speed, and enhancing focusing performance in low-light environments. In some cases, the camera module 10 may also have space for optical image stabilization (OIS) movement, facilitating improved image quality through OIS movement.

[0085] In this embodiment, when the camera module 10 is in a non-working mode, that is, when the camera module 10 is not in any specific operation or function setting state, such as power-off state, standby state, fault state, etc., the lens in the optical lens can return to the retracted state (to be further described below), and the module cover plate 101 can be lowered and housed in the opening 20a. At this time, the electronic device 1 returns to its initial appearance and does not affect the thickness of the electronic device 1.

[0086] Therefore, by setting a liftable module cover 101, this embodiment can utilize the external space of the electronic device 1 to meet the travel requirements of the optical lens without increasing the thickness of the electronic device 1, thus achieving both imaging quality and thinness.

[0087] In another embodiment, the internal space of the electronic device 1 can accommodate the travel requirements of the optical lens, and the module cover 101 can be fixed without needing to be raised or lowered. Accordingly, the optical lens does not have a retracted state.

[0088] The above provides an overview of the basic structure of the camera module 10. The following section will describe in detail the optical lens in the camera module 10.

[0089] Figure 3 is a side view schematic diagram of the optical lens 102 in one embodiment. Figure 3 also illustrates the aperture 103 and image sensor 104 in the camera module 10. Exemplarily, the aperture 103, optical lens 102, and image sensor 104 can be arranged sequentially along the optical axis O (e.g., along the Z direction in Figure 3), with the aperture 103 located on the object side of the optical lens 102 (which can be referred to as front-mounted aperture), and the image sensor 104 located on the image side of the optical lens 102. In this embodiment, the optical lens 102, when paired with the aperture 103, can achieve closer object distance photography, which is beneficial for improving the depth of field range of the entire image in close-range photography.

[0090] In the front-positioned aperture architecture of this embodiment, since the thickness of the aperture 103 is not included in the TTL of the optical lens 102, it is beneficial to reduce the TTL of the optical lens 102. In another embodiment, the aperture 103 can be positioned in other locations as needed, including but not limited to being positioned between the first lens group G1 and the second lens group G2 in the optical lens 102 (which can be referred to as a center-positioned aperture).

[0091] As shown in Figure 3, in this embodiment, the optical lens 102 may include at least three lens groups, each lens group including a plurality of lenses. For example, the optical lens 102 may include a first lens group G1, a second lens group G2, and a third lens group G3, arranged sequentially along the direction from the object side to the image side, and arranged along the optical axis O. The optical axis O is along the Z direction in Figure 3.

[0092] In this embodiment, the first lens group G1 may include at least one lens, such as lens G11 and lens G12 illustrated in Figure 3. The structure of each lens can be determined as needed, and this embodiment does not impose any limitations. The first lens group G1 may have positive optical power.

[0093] In this embodiment, the second lens group G2 may include several lenses, for example, at least two lenses, as illustrated in Figure 3, which shows three lenses: lens G21, lens G22, and lens G23. The structure of each lens can be determined as needed, and this embodiment does not impose any limitations. The second lens group G2 may have positive optical power.

[0094] In this embodiment, the third lens group G3 may include several lenses, for example, at least two lenses, as illustrated in Figure 3, which shows three lenses: lens G31, lens G32, and lens G33. The structure of each lens can be determined as needed, and this embodiment does not impose any limitations. The third lens group G3 may have negative optical power.

[0095] In this embodiment, the lens parameters in the optical lens 102 can be determined as needed. Various lens parameters in the optical lens 102 will be listed in tabular form below as an example.

[0096] Table 1a illustrates some lens parameters of the optical lens 102 in this embodiment, including the names of each lens group, the names of each lens in each lens group, the incident surface S1 and the exit surface S2 of each lens, the central radius of curvature of each lens surface, the central thickness, the refractive index nd, and the Abbe number of each lens. The central thickness refers to the gap between each lens surface and the next adjacent lens surface. For example, the gap between the central thickness 2.07E+00 of the incident surface S1 of lens G11 and the exit surface S2 of lens G11, and so on. Among them, the light-emitting surface S2 of lens G12 corresponds to five center thickness values ​​(5.76E+00, 5.64E+00, 5.82E+00, 5.99E+00, and 1.46E+00), each center thickness value corresponding to a working state (72mm focal length state, 96mm focal length state, 108mm focal length state, 120mm focal length state, and macro state at 120mm focal length). This means that the gap between the light-emitting surface S2 of lens G12 and the light-incident surface S1 of lens G21 is different in different working states, hence they are listed separately. Similarly, the light-emitting surface S2 of lens G23 also corresponds to five center thickness values, the meaning of which is as described above. The following will explain that relative movement can occur between lens groups (lenses within the same lens group will not have relative movement). Therefore, the gap between two adjacent lenses belonging to different lens groups can be variable. For example, the gap between lens G12 of the first lens group G1 and lens G21 of the second lens group G2 can be variable. This variable gap is reflected in Table 1a, which shows the different center thickness values ​​corresponding to different operating states.

[0097] Table 1a Partial lens parameters of optical lens 102

[0098] For example, the aspherical surface profile of each lens can be defined using the following aspherical formula:

[0099] Where x is the sag of the aspherical surface, c is the curvature of the vertex sphere of the aspherical surface, c is the reciprocal of the radius of curvature of the center, y is the diameter of the aspherical surface, k is the quadratic surface constant, and a, b, c, etc. are the aspherical coefficients of the 4th, 6th, and 8th orders, respectively.

[0100] Tables 1b and 1c illustrate the other lens parameters for each lens surface in Table 1a, including the quadratic surface constant k and the aspheric coefficients of each order. For example, the 4th order aspheric coefficient is the value in column 4th, the 30th order aspheric coefficient is the value in column 30th, and so on.

[0101] Table 1b contains partial lens parameters for optical lens 102.

[0102] Table 1c shows some lens parameters of optical lens 102.

[0103] In this embodiment, the first lens group G1, the second lens group G2, and the third lens group G3 can form a reverse telephoto architecture, which will be described below.

[0104] Figure 4 illustrates the schematic principle of the reverse telephoto structure formed by the first lens group G1, the second lens group G2, and the third lens group G3. As shown in Figure 4, when a ray of light parallel to the optical axis at infinity enters the optical lens 102, it first passes through the first lens group G1 and the second lens group G2, which have positive optical power, and converges to a certain extent. After converging, the ray of light passes through the third lens group G3, which has negative optical power, and diverges to a certain extent, finally illuminating the image sensor 104 to achieve imaging. According to optical principles, the relationship between the total optical length TTL and the effective focal length EFFL of the optical lens 102 can be determined by plotting: the distance from the object side of the first lens group G1 to the imaging plane is TTL. The distance along the optical axis between the point of intersection of the incident ray to the image sensor 104 and the incident ray parallel to the optical axis is EFFL. As shown in Figure 4, TTL < EFFL, that is, the optical lens 102 has a reverse telephoto structure.

[0105] The EFFL of the optical lens 102 is related to the specifications of the optical lens 102. In this embodiment, by making the optical lens 102 form a reverse telephoto architecture, the TTL can be limited to a range smaller than the EFFL. This is beneficial to reduce the TTL, so that the electronic device 1 does not need to have a large thickness to meet the zoom requirements of the optical lens 102, which is beneficial to the thinning of the electronic device 1.

[0106] For example, as shown in Figure 3, when the camera module 10 is in non-operating mode, the optical lens 102 can be in a retracted state. In the retracted state, the first lens group G1, the second lens group G2, and the third lens group G3 can be brought together, and the total optical length TTL0 of the optical lens 102 is minimized. As mentioned above, when the camera module 10 includes a retractable module cover 101, the module cover 101 can be accommodated within the opening 20a, thus maintaining a smaller thickness for the electronic device 1.

[0107] In this embodiment, when the camera module 10 is in working mode, the drive mechanism (e.g., including a motor) in the camera module 10 can drive the lens group in the optical lens 102 to move along the optical axis, so that the optical lens 102 changes from a retracted state to a working state, realizing zoom and focus. This will be explained below.

[0108] In this embodiment, the optical lens 102 can have multiple operating states. For example, the operating states of the optical lens 102 may include a first operating state (Figure 5), a second operating state (Figure 6), a third operating state (Figure 7), a fourth operating state (Figure 8), and a fifth operating state (Figure 9). The focal lengths of the first, second, third, and fourth operating states increase sequentially; for example, the focal lengths of the first, second, third, and fourth operating states may be 72mm, 96mm, 108mm, and 120mm, respectively.

[0109] For example, the optical lens 102 can be a telephoto lens, for instance, its field of view (FOV1) in the first working state (e.g., corresponding to a 72mm focal length) can be up to 50°, that is, FOV1 ≤ 50°. Depending on the needs, FOV1 can be 40°, 50°, etc. The solution of this embodiment can implement a reverse telephoto architecture based on a telephoto lens, thereby reducing TTL.

[0110] The above description of the working state corresponding to the 72mm focal length as the first working state and the working state corresponding to the 96mm focal length as the second working state is merely an example and not a limitation on the embodiments of this application. In practice, in the embodiments of this application, the working states corresponding to any two different effective focal lengths can be referred to as the first working state and the second working state, respectively, wherein the effective focal length in the first working state is less than the effective focal length in the second working state. For example, the working state corresponding to the 96mm focal length can also be referred to as the first working state, and the working state corresponding to the 120mm focal length can be referred to as the second working state.

[0111] For example, the aperture values ​​of the aperture 103 in the first working state, the second working state, the third working state, and the fourth working state can be 1.28, 1.70, 1.92, and 2.13, respectively.

[0112] Referring to Figures 3 and 5, exemplarily, during the transition of the optical lens 102 from the retracted state to the first working state, the first lens group G1 and the second lens group G2 can both move along the optical axis O towards the object side, while the third lens group G3 can remain stationary. It can be understood that during the transition from the retracted state to the first working state, the TTL of the optical lens 102 increases; the TTL1 of the optical lens 102 in the first working state is greater than the TTL0 in the retracted state. In another embodiment, during the transition of the optical lens 102 from the retracted state to the first working state, the first lens group G1, the second lens group G2, and the third lens group G3 can all move along the optical axis O towards the object side.

[0113] Referring to Figures 5 and 6, during the transition from the first operating state to the second operating state of the optical lens 102, both the first lens group G1 and the third lens group G3 move along the optical axis towards the object side of the optical lens 102, increasing the distance between the first lens group G1 and the third lens group G3 and the imaging plane. For example, the displacement of the third lens group G3 can be greater than the displacement of the first lens group G1. During the transition from the first operating state to the second operating state, the optical lens 102 can achieve zoom from short focal length to long focal length, for example, from a 72mm focal length to a 96mm focal length. It can be understood that the TTL2 of the optical lens 102 in the second operating state is greater than the TTL1 in the first operating state.

[0114] Referring to Figures 5 and 6, by way of example, during the transition of the optical lens 102 from the first operating state to the second operating state, the second lens group G2 may remain stationary. As will be described below, the second lens group G2 is used to move towards the object side after zooming to achieve focusing.

[0115] In another example, during zooming, as the optical lens 102 changes from a first operating state to a second operating state, the second lens group G2 can also move towards the object side. This design is beneficial for increasing the zoom ratio of the optical lens 102.

[0116] Referring to Figures 6 and 7, during the transition from the second to the third operating state of the optical lens 102, both the first lens group G1 and the third lens group G3 move towards the object side of the optical lens 102, and the distance between the first lens group G1 and the third lens group G3 and the imaging plane continues to increase. For example, the displacement of the third lens group G3 can be greater than the displacement of the first lens group G1. During the transition from the second to the third operating state, the optical lens 102 can achieve zoom from short focal length to long focal length, for example, from a 96mm focal length to a 108mm focal length. It can be understood that the TTL3 of the optical lens 102 in the third operating state is greater than the TTL2 in the second operating state. Referring to Figures 7 and 8, during the transition from the third to the fourth operating state of the optical lens 102, both the first lens group G1 and the third lens group G3 move towards the object side of the optical lens 102, and the distance between the first lens group G1 and the third lens group G3 and the imaging plane continues to increase. For example, the displacement of the third lens group G3 can be greater than the displacement of the first lens group G1. During the transition from the third to the fourth operating state, the optical lens 102 can achieve zoom from a short focal length to a long focal length, for example, from a 108mm focal length to a 120mm focal length. It can be understood that the TTL4 of the optical lens 102 in the fourth operating state is greater than the TTL3 in the third operating state. In summary, the optical lens 102 can switch from a retracted state to an operating state to achieve zoom, and the total optical length TTL0 of the optical lens 102 in the retracted state is less than the total optical length in any operating state, that is, less than the total optical length TTT1 in the first operating state.

[0117] The above example illustrates how the optical lens 102 sequentially changes from a retracted state to the first, second, third, and fourth working states. This is merely an example. In reality, the optical lens 102 can directly change from one state to another, such as directly changing from the retracted state to the second, third, or fourth working state, or directly changing from the first working state to the third or fourth working state, and so on.

[0118] In another embodiment, the optical lens 102 may not have a retracted state, and the initial position of the optical lens 102 may be set to any working state position. After use, the optical lens 102 may remain in the working state at the last use or the initial position.

[0119] As can be easily understood from Figures 5-8 and the above description, the zoom process from telephoto to focal length is the reverse of the zoom process from focal length to telephoto. That is, during the zoom process from telephoto to focal length, both the first lens group G1 and the third lens group G3 move towards the image side of the optical lens 102. For example, during the transition from the fourth operating state to the third operating state, both the first lens group G1 and the third lens group G3 move towards the image side of the optical lens 102. During the zoom process from telephoto to focal length, the optical lens 102 can zoom sequentially to gradually decrease the focal length, or it can zoom abruptly from a larger focal length to a smaller focal length (e.g., directly zooming from a 120mm focal length to a 96mm focal length).

[0120] According to optical principles, the relative motion between the first lens group G1, which has positive optical power, and the third lens group G3, which has negative optical power, has a significant impact on the EFFL of the optical lens 102. To improve the zoom ratio of the optical lens 102, i.e., to increase the effective focal length EFFL of the optical lens 102 at its maximum focal length... max With the minimum effective focal length EFFL min During zooming, the ratio of the first lens group G1 to the third lens group G3 along the optical axis can be adjusted to either result in a larger displacement of the first lens group G1 or a larger displacement of the third lens group G3 along the optical axis. However, a larger displacement of the first lens group G1 along the optical axis would lead to a higher TTL for the optical lens 102. In contrast, a larger displacement of the third lens group G3 along the optical axis would not only allow the optical lens 102 to have a larger zoom ratio but also prevent the TTL of the optical lens 102 from becoming too high. Therefore, in this embodiment, during zooming, the displacement of the third lens group G3 along the optical axis can be greater than the displacement of the first lens group G1 along the optical axis.

[0121] It is understood that, as needed, in another embodiment, the displacement relationship between the third lens group G3 and the first lens group G1 during zooming may not be limited. For example, the displacements of the third lens group G3 and the first lens group G1 may be substantially the same or the former may be less than the latter.

[0122] In this embodiment, after the optical lens 102 completes zooming, the first lens group G1 and the third lens group G3 can remain stationary in their working positions, while the second lens group G2 can move along the optical axis toward the object side to enable the optical lens 102 to focus and ensure clear imaging. For example, as shown in Figure 9, at the maximum focal length (e.g., 120mm), when the object to be photographed is relatively close to the optical lens 102 (e.g., the object distance is about 30mm, also known as macro mode), the second lens group G2 can move a greater distance toward the object side to ensure clear imaging on the image sensor 104 and guarantee image quality. The state of the optical lens 102 shown in Figure 9 can be referred to as the fifth working state.

[0123] The optical lens 102 described above has four focal length states, enabling zoom across four focal lengths. This is merely an example and not a limitation on the embodiments of this application. In fact, the optical lens 102 of this application embodiment may have at least two focal length states, enabling zoom across at least two focal lengths.

[0124] In this embodiment, the optical lens 102 can form a reverse telephoto architecture at any focal length. By enabling the optical lens 102 to form a reverse telephoto architecture, it is beneficial to reduce the TTL of the optical lens 102, allowing the electronic device 1 to meet the zoom requirements of the optical lens 102 without requiring a large thickness, thus facilitating the thinning of the electronic device 1. In addition, the optical lens 102 achieves zooming through the movement of the lens group, and the TTL is variable during zooming, breaking the limitation of the fixed TTL in traditional solutions during zooming, thereby releasing design freedom and meeting more imaging requirements. Furthermore, each lens group in the optical lens 102 moves along the optical axis, allowing external light to continuously enter the optical lens 102 and be incident on the image sensor 104 during zooming and focusing, avoiding the black screen phenomenon during state switching.

[0125] In this embodiment, the total optical length (TTL) of the optical lens 102 at its maximum focal length is... max Total optical length (TTL) at the smallest focal length min Effective focal length (EFFL) at maximum focal length max And the effective focal length EFFL at the smallest focal length min The following relationship can be satisfied: TTL max -TTL min ≤EFFL max -EFFL min .

[0126] In this embodiment, the TTL of the optical lens 102 min TTL max EFFL min and EFFL max It can also satisfy the following relationship: TTL max / TTL min ≤EFFL max / EFFL min For example, TTL max / TTL min It can be (1, 3] or (1, 1.5], for example, 1.12, 1.5, 2.23, etc.; EFFL max / EFFL min It can be (1, 3] or (1, 1.5], for example, 1.47, 1.5, 2, etc.

[0127] Among them, for example:

[0128] TTL max For example, it can be between 11.5mm and 46mm, or between 16.1mm and 29.9mm. Specific values ​​could be 11.5mm, 16.1mm, 23mm, 29.9mm, 46mm, etc.

[0129] TTL min For example, it can be between 10.3mm and 41.2mm, or between 14.42mm and 26.78mm. Specific values ​​could be 10.3mm, 14.42mm, 20.6mm, 26.78mm, 41.2mm, etc.

[0130] EFFL max It can be between 8mm and 80mm, or between 9.75mm and 39mm, or between 13.65mm and 25.35mm. Specific values ​​are, for example, 8mm, 9.75mm, 13.65mm, 19.5mm, 25.35mm, 39mm, 80mm, etc.

[0131] EFFL min The thickness can be between 4mm and 40mm, or between 6.63mm and 26.52mm, or between 9.282mm and 17.238mm. Specific values ​​include, for example, 4mm, 6.63mm, 9.282mm, 13.26mm, 17.238mm, 26.52mm, and 40mm.

[0132] TTL in optical lens 102 min TTL max EFFL min and EFFL max It can satisfy either of the two relations mentioned above, or both at the same time.

[0133] In this embodiment, TTL max -TTL min With TTL max / TTL min It can indicate the range of TTL variation. By limiting the range of TTL variation to the above range, it is possible to avoid excessive TTL variation that would cause excessive travel of the first lens group G1, which is beneficial to simplify the drive mechanism of the optical lens 102 and also saves the space occupied by the drive mechanism (if the travel is too large, the drive mechanism needs to be more complex and will also occupy more space).

[0134] In another embodiment, TTL may not be required. max -TTL minand / or TTL max / TTL min The above restrictions apply.

[0135] In this embodiment, the effective focal length EFFL2 of the second lens group G2 and the effective focal length EFFL of the optical lens 102 at its maximum focal length are... max And the effective focal length EFFL of optical lens 102 at its minimum focal length min The following relationship can be satisfied: 0.3*EFFL max ≤EFFL2≤EFFL max And 0.3*EFFL min ≤EFFL2≤EFFL min Or satisfy 0.3*EFFL max ≤EFFL min And 0.3*EFFL max ≤EFFL2≤EFFL min Or satisfy 0.6*EFFL max ≤EFFL min And 0.6*EFFL max ≤EFFL2≤EFFL min EFFL2 can be determined as needed, for example, it can be 10.6 mm. max With EFFL min The value can be as described above.

[0136] Since the optical power of the second lens group G2 is inversely proportional to EFFL2, the range of the optical power of the second lens group G2 can be limited by limiting the range of EFFL2. By limiting the optical power of the second lens group G2 within the reasonable range mentioned above, good image quality and high motor accuracy can be guaranteed (excessive optical power will cause the second lens group G2 to generate too many aberrations, making the image quality unsatisfactory during focusing; while excessive optical power will result in an excessively long focusing stroke, thereby reducing the accuracy of the motor (focusing stroke and accuracy are usually inversely proportional)).

[0137] In another embodiment, EFFL2 may not be subject to the above limitations.

[0138] In this embodiment, the effective focal length EFFL of the optical lens 102 at its maximum focal length max And the effective focal length EFFL of optical lens 102 at the minimum effective focal length min Satisfy the following relationship: EFFL max / EFFL min ≥1.3. For example, 1.3≤EFFL max / EFFL min ≤1 / 0.3, or 1.3≤EFFLmax / EFFL min ≤1 / 0.6. Wherein, EFFL max With EFFL min The value of EFFL max / EFFL min The value can be as described above. EFFL max / EFFL min This refers to the zoom ratio of the optical lens. By limiting the zoom ratio of the optical lens to this range, a wider field of view can be achieved, thus improving image quality.

[0139] In this embodiment, the effective focal length EFFL1 of the first lens group G1 is greater than or equal to the effective focal length EFFL of the optical lens 102 at its maximum focal length. max EFFL1 can be determined as needed, for example, it can be between 18.3mm and 73.2mm, such as 18.3mm, 36.6mm, 73.2mm, etc. EFFL max It can be as described above, for example, 19.5mm. An example is EFFL1 / EFFL. max It can be between 1 and 4, for example, 1.88, etc. This is achieved by limiting EFFL1 and EFFL. max The relationship can improve the zoom ratio of the optical lens 102.

[0140] In another embodiment, the effective focal length EFFL1 of the first lens group G1 may not be limited as described above.

[0141] Figures 10, 11, 12, 13, and 14 illustrate the modulation transfer function (MTF) contrast transfer curves of the optical lens 102 in the first operating state (72mm focal length), the second operating state (96mm focal length), the third operating state (108mm focal length), the fourth operating state (120mm focal length), and the fifth operating state (macro mode at 120mm focal length) in this embodiment, respectively. The horizontal axis represents the defocusing position, and the vertical axis represents the contrast ratio. Each continuous curve represents the MTF contrast transfer curve corresponding to different field of view angles. The more concentrated the curves (i.e., the peak of the sinc function appears near zero on the horizontal axis), the better the image quality.

[0142] As shown in Figures 10-14, most of the peaks of the sinc function are concentrated at the zero position on the horizontal axis, indicating that the imaging quality after adopting the scheme of this embodiment is better.

[0143] In the above embodiments, after zooming is completed, the first lens group G1 and the third lens group G3 remain in their current positions, while the second lens group G2 moves along the optical axis toward the object side to achieve focusing. Based on the above embodiments, the embodiments described below will adjust the focusing process from solely using the movement of the second lens group G2 to the joint movement of the first lens group G1 and the second lens group G2 to achieve focusing.

[0144] In the embodiments shown in Figures 15-18, after the optical lens 102 completes zooming, the third lens group G3 can remain in its current position, while the first lens group G1 and the second lens group G2 can both move along the optical axis towards the object side to enable the optical lens to focus. Specifically, the displacements of the first lens group G1 and the second lens group G2 are the same. This ensures that the displacements of the first lens group G1 and the second lens group G2 are identical, making it easier for the motor of the lens group to determine the focusing position and reducing the control complexity of the lens group's drive mechanism.

[0145] In the operating state illustrated in Figure 15, the focal length of the optical lens 102 can be, for example, 72mm. In the operating state illustrated in Figure 16, the focal length of the optical lens 102 can be, for example, 108mm. In the operating state illustrated in Figure 17, the focal length of the optical lens 102 can be, for example, 120mm. In the operating state illustrated in Figure 18, the focal length of the optical lens 102 can be, for example, 120mm, and the optical lens 102 is in macro mode (e.g., object distance of 30mm).

[0146] Table 2a illustrates some lens parameters of the optical lens 102 in this embodiment, including the name of each lens group, the name of each lens in each lens group, the light-incident surface S1 and the light-outceasing surface S2 of each lens, the central radius of curvature of each lens surface, the central thickness, the refractive index nd, and the Abbe number of each lens.

[0147] Table 2a Partial lens parameters of optical lens 102

[0148] Tables 2b and 2c illustrate other lens parameters for each lens surface in Table 2a, including the quadratic surface constant k and the aspherical coefficients of each order.

[0149] For example, the 4th order aspherical coefficient is the value in column 4th, the 30th order aspherical coefficient is the value in column 30th, and so on.

[0150] Table 2b contains partial lens parameters for optical lens 102.

[0151] Table 2c shows some lens parameters for optical lens 102.

[0152] In this embodiment, after zooming is completed, focusing can be achieved by moving both the first lens group G1 and the second lens group G2. This also increases design freedom and meets some product design requirements.

[0153] In this embodiment, the TTL of the optical lens 102 max TTL min EFFL max and EFFL min The following relationship can be satisfied: TTL max -TTL min ≤EFFL max -EFFL min .

[0154] For example, the TTL of optical lens 102 min TTL max EFFL min and EFFL max It can also satisfy the following relationship: TTL max / TTL min ≤EFFL max / EFFL min For example, TTL max / TTL min It can be (1, 3] or (1, 1.5], for example, 1.12, 1.5, 2.23, etc.; EFFL max / EFFL min It can be (1, 3] or (1, 1.5], for example, 1.47, 1.5, 2, etc.

[0155] Among them, for example:

[0156] TTL max For example, it can be between 11.5mm and 46mm, or between 16.1mm and 29.9mm. Specific values ​​could be 11.5mm, 16.1mm, 23mm, 29.9mm, 46mm, etc.

[0157] TTL min For example, it can be between 10mm and 40mm, or between 14mm and 26mm. Specific values ​​can be, for example, 10mm, 14mm, 20mm, 26mm, 40mm, etc.

[0158] EFFL maxIt can be between 8mm and 80mm, or between 9.75mm and 39mm, or between 13.65mm and 25.35mm. Specific values ​​are, for example, 8mm, 9.75mm, 13.65mm, 19.5mm, 25.35mm, 39mm, 80mm, etc.

[0159] EFFL min The thickness can be between 4mm and 40mm, or between 6.65mm and 26.6mm, or between 9.31mm and 17.29mm. Specific values ​​include, for example, 4mm, 6.65mm, 9.31mm, 13.3mm, 17.29mm, 26.6mm, and 40mm.

[0160] TTL in optical lens 102 min TTL max EFFL min and EFFL max It can satisfy either of the two relations mentioned above, or both at the same time.

[0161] In this embodiment, TTL max -TTL min With TTL max / TTL min Both can indicate the range of TTL variation. By limiting the range of TTL variation to the above range, it is possible to avoid excessive TTL variation leading to excessive travel of the first lens group G1, which helps to simplify the drive mechanism of the optical lens 102 and also saves the space occupied by the drive mechanism (if the travel is too large, the drive mechanism needs to be more complex and will also occupy more space).

[0162] In another embodiment, TTL may not be required. max -TTL min and / or TTL max / TTL min The above restrictions apply.

[0163] In this embodiment, the effective focal length EFFL2 of the second lens group G2 and the effective focal length EFFL of the optical lens 102 at its maximum focal length are... max And the effective focal length EFFL of optical lens 102 at its minimum focal length min The following relationship can be satisfied: 0.3*EFFL max ≤EFFL2≤EFFL max And 0.3*EFFL min ≤EFFL2≤EFFL min Or satisfy 0.3*EFFL max ≤EFFL min And 0.3*EFFLmax ≤EFFL2≤EFFL min Or satisfy 0.6*EFFL max ≤EFFL min And 0.6*EFFL max ≤EFFL2≤EFFL min EFFL2 can be determined as needed, for example, it can be 10.6 mm. max With EFFL min The value can be as described above.

[0164] Since the optical power of the second lens group G2 is inversely proportional to EFFL2, the range of the optical power of the second lens group G2 can be limited by limiting the range of EFFL2. By limiting the optical power of the second lens group G2 within the reasonable range mentioned above, good image quality and high motor accuracy can be guaranteed (excessive optical power will cause the second lens group G2 to generate too many aberrations, making the image quality unsatisfactory during focusing; while excessive optical power will result in an excessively long focusing stroke, thereby reducing the accuracy of the motor (focusing stroke and accuracy are usually inversely proportional)).

[0165] In another embodiment, EFFL2 may not be subject to the above limitations.

[0166] In this embodiment, the effective focal length EFFL of the optical lens 102 at its maximum effective focal length max And the effective focal length EFFL of optical lens 102 at the minimum effective focal length min Satisfy the following relationship: EFFL max / EFFL min ≥1.3. For example, 1.3≤EFFL max / EFFL min ≤1 / 0.3, or 1.3≤EFFL max / EFFL min ≤1 / 0.6. Wherein, EFFL max With EFFL min The value of EFFL max / EFFL min The value can be as described above. EFFL max / EFFL min This refers to the zoom ratio of the optical lens. By limiting the zoom ratio of the optical lens to this range, a wider field of view can be achieved, thus improving image quality.

[0167] In this embodiment, the effective focal length EFFL1 of the first lens group G1 is greater than or equal to the effective focal length EFFL of the optical lens 102 at its maximum focal length. maxEFFL1 can be determined as needed, for example, it can be between 16.65mm and 66.6mm, such as 16.65mm, 33.3mm, 66.6mm, etc. EFFL max It can be as described above, for example, 19.5mm. An example is EFFL1 / EFFL. max It can be between 1 and 4, for example, 1.71, etc. This is achieved by limiting EFFL1 and EFFL. max The relationship can improve the zoom ratio of the optical lens 102.

[0168] Figures 19, 20, 21, and 22 illustrate the MTF contrast transfer curves of the optical lens 102 at different focal lengths. Figures 19 to 22 correspond one-to-one with Figures 15 to 18. As shown in Figures 19-22, most of the peaks of the sinc function are concentrated at the zero point on the horizontal axis, indicating that the imaging quality after adopting the scheme of this embodiment is better.

[0169] For ease of understanding, the relevant technical terms involved in the embodiments of this application will be explained and described below.

[0170] In the description of the embodiments in this application, unless otherwise stated, "multiple" means two or more.

[0171] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Features specified as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0172] The term "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. Similarly, "fixation" should also be interpreted broadly. For example, "fixation" can be direct fixation or indirect fixation through an intermediate medium.

[0173] The directional terms mentioned in the embodiments of this application, such as "upper," "lower," "front," "rear," "left," "right," "inner," "outer," "side," "top," and "bottom," are only for reference to the directions in the accompanying drawings. These directional terms are used to better and more clearly explain and understand the embodiments of this application, and are not intended to explicitly or implicitly suggest that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, etc., and therefore should not be construed as limiting the embodiments of this application.

[0174] In the description of the embodiments in this application, unless otherwise stated, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone.

[0175] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An optical lens, characterized in that, The optical lens comprises a first lens group, a second lens group, and a third lens group, arranged sequentially from the object side to the image side. The first lens group and the second lens group both have positive optical power, and the third lens group has negative optical power. The first lens group, the second lens group, and the third lens group are all used to move along the optical axis of the optical lens and enable the optical lens to zoom, wherein: During the process of the optical lens changing from the first working state to the second working state, both the first lens group and the third lens group move toward the object side, wherein the effective focal length of the optical lens in the first working state is less than the effective focal length in the second working state. The second lens group is used to move along the optical axis toward the object side after the optical lens has completed zooming, so that the optical lens can achieve focus.

2. The optical lens according to claim 1, characterized in that, During the zooming process of the optical lens, the displacement of the third lens group along the optical axis is greater than the displacement of the first lens group along the optical axis.

3. The optical lens according to claim 1 or 2, characterized in that, The total optical length (TTL) of the optical lens at its maximum focal length max Total optical length (TTL) at the smallest focal length min Effective focal length (EFFL) at maximum focal length max And the effective focal length EFFL at the smallest focal length min Satisfying the following relationship: TTL max -TTL min ≤EFFL max -EFFL min .

4. The optical lens according to claims 1-3, characterized in that, The total optical length (TTL) of the optical lens at its maximum focal length max Total optical length (TTL) at the smallest focal length min Effective focal length (EFFL) at maximum focal length max And the effective focal length EFFL at the smallest focal length min Satisfying the following relationship: TTL max / TTL min ≤EFFL max / EFFL min .

5. The optical lens according to claims 1-4, characterized in that, During the process of the optical lens changing from the first working state to the second working state, the second lens group is used to move toward the object side.

6. The optical lens according to any one of claims 1-5, characterized in that, The first lens group is also used to move along the optical axis toward the object side after the optical lens has completed zooming, so that the optical lens can achieve focusing, wherein the displacement of the first lens group is the same as that of the second lens group.

7. The optical lens according to any one of claims 1-6, characterized in that, The optical lens has a retracted state, and the total optical length TTL0 of the optical lens in the retracted state is less than the total optical length TTL1 in the first working state.

8. The optical lens according to any one of claims 1-7, characterized in that, The effective focal length EFFL2 of the second lens group and the effective focal length EFFL of the optical lens at its maximum focal length. max and the effective focal length (EFFL) at the smallest focal length min It satisfies the following relationship: 0.3*EFFL max ≤EFFL min 0.3*EFFL max ≤EFFL2≤EFFL min .

9. The optical lens according to any one of claims 1-8, characterized in that, The effective focal length (EFFL) of the optical lens at its maximum focal length max With the effective focal length EFFL at the smallest focal length min Satisfy the following relationship: EFFL max / EFFL min ≥1.

3.

10. The optical lens according to claim 9, characterized in that, 1.3≤EFFL max / EFFL min ≤1 / 0.3。 11. The optical lens according to any one of claims 1-10, characterized in that, The effective focal length EFFL1 of the first lens group is greater than or equal to the effective focal length EFFL of the optical lens at its maximum focal length. max .

12. The optical lens according to any one of claims 1-11, characterized in that, The field of view (FOV1) of the optical lens in the first working state is ≤50°.

13. The optical lens according to any one of claims 1-12, characterized in that, The first lens group includes at least one lens, and / or the second lens group includes at least two lenses, and / or the third lens group includes at least two lenses.

14. A camera module, characterized in that, It includes an image sensor and an optical lens as described in any one of claims 1-13, wherein the image sensor is located on the image side of the optical lens.

15. The camera module according to claim 14, characterized in that, The camera module is used to be installed in an electronic device, and the optical axis is perpendicular to the display screen of the electronic device.

16. The camera module according to claim 15, characterized in that, The camera module includes a module cover plate, which is disposed on the object side of the optical lens and is used to cover the opening of the electronic device. The module cover plate is also used to move along the optical axis of the optical lens.

17. The camera module according to any one of claims 14-16, characterized in that, The camera module also includes a variable aperture, which is located on the light-incident side of the image sensor.

18. The camera module according to claim 17, characterized in that, The variable aperture is located on the object side of the optical lens.

19. An electronic device, characterized in that, It includes a main body and a camera module as described in any one of claims 14-18, wherein the camera module is disposed on the main body.

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