Lens module and electronic equipment

Abstract

The embodiment of the invention provides a lens module and electronic equipment, the lens module comprises a supporting piece and a lens, the supporting piece is provided with a supporting groove, and the circumferential edge of the lens is connected in the supporting groove; wherein the sign of the thermal expansion coefficient of the supporting piece is opposite to that of the thermal expansion coefficient of the lens. According to the lens module provided by the embodiment of the invention, the stable performance in the environment temperature change process is ensured under the condition that the structural complexity is not improved.

Description

Technical Field

[0001] This application belongs to the field of camera technology, specifically relating to a lens module and an electronic device. Background Technology

[0002] As the functionality of camera modules improves, their power consumption also increases. The image sensor, voice coil motor, and image processing chip within the camera module generate significant heat during prolonged operation, causing lens expansion and resulting in issues such as focus shift, blurring, and lag, thus affecting the camera module's performance.

[0003] In related technologies, methods such as adding heat dissipation structures, adjusting algorithms, and changing lens materials can, to some extent, compensate for the performance degradation of camera modules caused by thermal expansion of the lenses. However, these methods increase the complexity of the camera system and have limited effect on improving the performance of the camera module. Summary of the Invention

[0004] This application aims to provide a lens module and electronic device that can solve the problem of performance degradation of existing camera modules caused by thermal expansion of the lens.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application propose a lens module, the lens module comprising: a support member and a lens, the support member being provided with a support groove, and the circumferential edge of the lens being connected within the support groove; The coefficient of thermal expansion of the support member has the opposite sign to that of the coefficient of thermal expansion of the lens.

[0006] Secondly, embodiments of this application provide an electronic device including a lens module as described in any of the preceding claims.

[0007] In this embodiment, the lens module includes a support member and a lens. The support member has a support groove. Since the circumferential edge of the lens is connected to the support groove of the support member, the support member can support the lens through the support groove, thus maintaining the stability of the lens during the operation of the lens module. In this embodiment, since the thermal expansion coefficient of the support member has the opposite sign to that of the lens, when the lens tends to deform under changes in ambient temperature, the support member can undergo the opposite deformation under the same ambient temperature change conditions. This can limit the deformation of the lens to a certain extent through its own deformation, thereby reducing problems such as focus shift, defocus blur, and response lag caused by changes in ambient temperature. This ensures stable performance during ambient temperature changes without increasing the complexity of the lens module.

[0008] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0009] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a simplified cross-sectional diagram of a camera module in related technologies; Figure 2 This is a simplified cross-sectional diagram of a lens module in related technologies; Figure 3 This is a schematic diagram of the thermal deformation of the support components and lens elements of a lens module in related technologies; Figure 4 This is a schematic diagram of the thermal deformation of the support member and lens of the lens module in one embodiment of this application; Figure 5 This is a simplified cross-sectional view of the lens module in another embodiment of this application; Figure 6 This is a schematic diagram of the thermal deformation of the lens module support and lens in another embodiment of this application; Figure 7 This is a schematic diagram of the connection structure between the piezoelectric actuator and the support in an embodiment of this application.

[0010] Reference numerals: 10-Support member, 11-First support member, 12-Second support member, 20-Lens, 30-Lens barrel, 40-Piezoelectric actuator, 41-Flexible circuit board, 50-Image sensor, 60-Lens mount, 70-Printed circuit board. Detailed Implementation

[0011] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0012] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0013] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0014] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0015] As the functionality of camera modules improves, their power consumption also increases. For example... Figure 1 The diagram shows the structure of a camera module in related technologies. In these technologies, the image sensor 50, voice coil motor, and image processing chip within the camera module all generate significant heat during prolonged operation. Specifically, the image sensor 50, as the core heat source, consumes 0.5-1.5 W / cm² of power per unit area during high-speed read / write and high-pixel data processing. The heat it generates is transmitted through the air... Figure 1The heat is transmitted upwards to the lens mount and lens element 20, as indicated by the middle arrow. Since the lens element 20 in the lens module is typically made of optical resin or glass, its coefficient of thermal expansion (CTE) is positive (approximately 6-10 ppm / ℃). Therefore, the lens element 20 receives heat from the image sensor 50, causing its temperature to rise and resulting in expansion along the lens module axis. Furthermore, during focusing and optical image stabilization operations, the coil resistance of the voice coil motor generates Joule heat, with a peak power of 0.2-0.5W. This heat is primarily transferred to the lens mount through the stator frame, causing the lens barrel 30 and lens element 20 to heat up. When the lens 20 expands due to increased temperature, it can easily cause problems such as focus shift (temperature drift), defocus blur, and response lag in the lens module, affecting the performance of the camera module. Among them, focus shift is caused by the increased radius of curvature and longer focal length of the lens after it expands due to heat, resulting in the image focus shifting backward. Defocus blur is caused by the superposition of deformation of multiple lens 20s in the lens, resulting in aberrations such as astigmatism and field curvature, which seriously affects image quality. Response lag is because the software algorithm needs to wait for the temperature sensor to feed back the temperature signal to compensate for the temperature drift of the lens 20, and cannot correct the dynamic deformation of the lens 20 in real time.

[0016] like Figure 2 The diagram shown is a simplified cross-sectional view of a lens module in a 25°C environment. The circumferential edge of the lens 20 extends into the support groove of the support member 10. The support member 10 is made of metal or plastic, and its coefficient of thermal expansion is positive, just like that of the lens 20. This type of support member 10 also exhibits thermal expansion and contraction deformation characteristics when subjected to heat generated by components such as the image sensor 50 or the voice coil motor. Figure 3 The figure shows a simplified cross-sectional diagram of a lens module in a 60°C environment. As shown, this type of support 10 operates in an environment where the temperature changes from... Figure 2 The temperature in the middle rose to 25°C. Figure 3At 60℃, both the lens 20 and the lens element 20 expand along the lens module axis, and the temperature drift caused by the expansion of the lens 20 cannot be compensated. In related technologies, some measures have been taken to compensate for the temperature drift caused by the thermal expansion of the lens 20 and the resulting performance degradation of the camera module. For example, passive heat dissipation is achieved by adding heat dissipation structures, such as applying graphene patches to the lens module or using metal brackets to improve heat dissipation. However, this passive heat dissipation method can only slow down the rate of temperature increase and has limited effect on adjusting lens performance. Alternatively, software algorithms can be adjusted to adjust the focus position based on a temperature table, but this method cannot correct the optical aberrations of the lens 20. Furthermore, the material of the lens 20 can be replaced with a glass material with a lower coefficient of thermal expansion. This increases the cost of the lens to some extent, and such glass has a higher density, which contradicts the trend of lens miniaturization and the trend of thinner and lighter electronic devices.

[0017] This application provides a lens module, which includes a support member 10 and a lens 20. The support member 10 is provided with a support groove, and the circumferential edge of the lens 20 is connected to the support groove. The thermal expansion coefficient of the support member 10 has the opposite sign to that of the thermal expansion coefficient of the lens 20.

[0018] In this embodiment, the lens module includes a support member 10 and a lens 20. The support member 10 is provided with a support groove. Since the circumferential edge of the lens 20 is connected to the support groove of the support member 10, the support member 10 can support the lens 20 through the support groove, and the lens 20 can be kept stable during the operation of the lens module. In this embodiment, since the thermal expansion coefficient of the support member 10 and the thermal expansion coefficient of the lens 20 have opposite signs, when the lens 20 tends to deform under the same temperature change, the support member 10 can undergo opposite deformation under the same temperature change conditions. This can limit the deformation of the lens 20 to a certain extent through its own deformation, thereby reducing problems such as focus shift, defocus blur, and response lag caused by the temperature change of the lens 20. This ensures the performance stability during the temperature change process without increasing the complexity of the lens module.

[0019] In specific applications, the lens module also includes a lens barrel 30, which is a cylindrical structure with an internal cavity. The support member 10 is disposed inside the cavity. The lens barrel 30 serves as the main support structure of the lens module, protecting the internal support member 10 and lens 20 from external impacts or scratches, ensuring the integrity and safety of the lens module. The support member 10 is connected to the inner wall of the lens barrel 30 and can contract or expand along the axial direction of the lens module when the ambient temperature changes. The support member 10 is designed as a ring structure adapted to the structure of the lens barrel 30, ensuring good contact and support with the lens barrel 30 along the circumference of the support member 10. The support groove is an annular groove disposed along the circumference of the support member 10 on the inner wall of the support member 10. The depth (radial direction) and width (axial direction) of the support groove can be flexibly designed according to the thickness and diameter of the lens 20, etc., and this embodiment does not specifically limit this. As a core functional component of the lens module, the lens 20 can change the direction of light propagation through its surface curvature, thereby converging incident light from different angles onto the focal plane. The lens module typically includes multiple lenses 20, which are spaced apart along the axial direction of the lens module to form a lens group. These lenses cooperate to precisely control the light path, projecting external scene information onto the image sensor 50 of the camera module to form a clear image. The lens 20 is a circular lens, with its circumferential edge connected to the support groove of the support member 10. With the circumferential edge of the lens 20 connected to the support groove, the projection of the lens 20 along the axial direction of the lens module at least partially overlaps with the projection of the support groove. Therefore, a mutual force can be generated between the circumferential edge of the lens 20 and the support groove of the support member 10. In this embodiment, the axial direction of the lens module is as follows... Figures 2 to 6 As indicated by the middle arrow Z.

[0020] In this embodiment, since the thermal expansion coefficients of the support member 10 and the lens 20 have opposite signs, the deformation directions of the support member 10 and the lens 20 are opposite when the ambient temperature inside the lens barrel 30 changes. In this embodiment, the thermal expansion coefficient of the support member 10 is negative, and the thermal expansion coefficient of the lens 20 is positive. Figure 4As shown, when the ambient temperature rises from 25°C to 60°C, the lens 20 expands along the axial direction of the lens module, while the support 10 contracts along the axial direction of the lens module. Since the circumferential edge of the lens 20 is connected within the support groove, i.e., along the axial direction of the lens module, the projection of the lens 20 at least partially overlaps with the projection of the support groove. The contraction of the support 10 along the axial direction of the lens module can suppress the expansion of the lens 20 along the axial direction of the lens module, thus achieving a temperature drift compensation effect for the lens 20, reducing the focal length change caused by the radial expansion of the lens 20, and avoiding defocusing and image degradation under high-temperature conditions. Since the support 10 is a structure already existing in related technologies, this application achieves control over the image quality of the lens module under high-temperature conditions by changing the material of the support 10, without increasing the complexity of the lens module. It is also compatible with existing camera module production line processes, achieving the goal of cost control. Furthermore, through this structural physical self-compensation mechanism, real-time suppression of thermal deformation of the lens module can be achieved, resulting in faster response speed and no algorithm delay.

[0021] In some optional embodiments of this application, such as Figure 4 As shown, there are multiple lenses 20, which are spaced apart along the axial direction of the lens module. The support member 10 has multiple support grooves, also spaced apart along the axial direction of the lens module. One lens 20 is connected to one support groove. When there are multiple lenses 20, they can work together to achieve functions such as focusing, zooming, optical image stabilization, and filtering. In this embodiment, by providing multiple support grooves on the support member 10 and connecting one lens 20 to one groove, one support member 10 can simultaneously compensate for temperature drift of multiple lenses 20. This simplifies the structural complexity of the lens module, facilitates processing and assembly, reduces material and manufacturing tolerances, and ensures the precision of the lens module.

[0022] Optionally, the coefficient of thermal expansion β of the support 10 and the coefficient of thermal expansion α of the lens 20 satisfy the following: , In specific applications, elemental doping during the solid-state sintering process in the manufacturing process of support component 10 (e.g., in Sc2W3O) can be achieved. 12 Medium-doped Mo 6+ or Si 4+ The negative thermal expansion coefficient β of the support 10 is finely adjusted so that the thermal expansion coefficient β of the support 10 and the thermal expansion coefficient α of the lens 20 satisfy the above relationship.

[0023] It should be noted that when the lens module contains multiple lens elements 20, the total expansion amount ΔD of the multiple lens elements 20 along the lens module axis is... total for: , Among them, D i The effective thickness (mm) of the i-th lens 20. i Let D be the coefficient of thermal expansion (ppm / ℃) of the i-th lens. i , i The value is determined when the lens 20 leaves the factory, and ΔT is the operating temperature rise (°C). The amount of contraction ΔL of the support member 10 in the lens module axial direction is: , Where L is the effective compensation dimension of the support 10 (mm), β is the coefficient of thermal expansion of the support 10 (ppm / ℃), L, The support component is determined at the time of manufacture, and ΔT is the operating temperature rise (°C). The ideal compensation conditions are: That is, the shrinkage of the support 10 is equal to the total expansion of the multiple lenses 20 to achieve the optimal compensation effect, i.e.: , After simplification, we get: ,Right now .

[0024] It should be understood that the coefficient of thermal expansion of the support component 10 may vary slightly between different production batches. This may be related to differences in raw materials, fluctuations in the process environment, and equipment conditions. Therefore, in practical applications, the coefficient of thermal expansion of the support component 10 will vary. The coefficient of thermal expansion of the lens 20 The above equation may not be fully satisfied; in practical applications, it can be controlled. The tolerance between them is within ±5% to ensure that the support component 10 inhibits the thermal expansion of the lens 20. Specifically, the materials of each production batch of support component 10 and lens 20 can be sampled and inspected using a thermomechanical analyzer (TMA) to ensure that the coefficients of thermal expansion of support component 10 and lens 20 are within the specified range.

[0025] Optionally, there may be multiple support members 10, which are spaced apart along the axial direction of the lens module. This reduces the number and weight of lenses 20 supported by a single support member 10, thereby enhancing its support stability. Simultaneously, when the lens module is subjected to external forces, the multiple support members 10 can better distribute the external load. For example, when the lens module is subjected to vibration, impact, or other external forces, the multiple support members 10 can work together, distributing the external force across each support member 10, reducing the stress on each support member 10, thus improving the overall impact and vibration resistance of the lens module and extending its service life.

[0026] For example, in such Figure 5 In the lens module shown, the support member 10 includes a first support member 11 (S1 in the figure) and a second support member 12 (S2 in the figure). The number of lenses 20 is four, including lens L1, lens L2, lens L3, and lens L4 along the direction of incident light. The circumferential edges of lenses L1 and L2 are connected to the support grooves of the first support member 11, and the circumferential edges of lenses L3 and L4 are connected to the support grooves of the second support member 12. Figure 6 As shown, when the temperature inside the lens barrel 30 rises to 60°C, lenses L1, L2, L3, and L4 all expand along the lens module axis, while the first support member 11 and the second support member 12 both contract along the lens module axis. The contraction of the first support member 11 can suppress the expansion of lenses L1 and L2, while the contraction of the second support member 12 suppresses the expansion of lenses L3 and L4. Thus, the pressure exerted by a single support member 10 on the expansion of lens 20 is smaller, thereby enhancing the suppression effect.

[0027] In specific applications, the diameters and thicknesses of multiple lenses 20 may be different. By setting multiple support members 10, one support member 10 can support multiple lenses 20 of the same size. That is, the dimensions of multiple support grooves on one support member 10 can be the same, which can simplify the manufacturing process of the support member 10 and help control production costs.

[0028] In some optional embodiments of this application, the multiple support members 10 have the same coefficient of thermal expansion, thereby enabling them to expand or contract synchronously in the same direction along the axial direction of the lens module when the temperature changes. This results in a more uniform constraint force on the multiple lenses 20 along the axial direction, which can more evenly suppress the curvature changes of the lenses 20 caused by temperature variations. Furthermore, in the design and manufacturing process of the support members 10, there is no need to consider the complex interactions between different support members 10 due to differences in their coefficients of thermal expansion. Multiple support members 10 can be manufactured using a single material and process, reducing manufacturing difficulty and cost, and improving production efficiency.

[0029] In some alternative embodiments of this application, the multiple support members 10 have different coefficients of thermal expansion. Specifically, the support members 10 with different coefficients of thermal expansion can be designed specifically according to the thermal expansion characteristics of different parts of the lens 20. It should be noted that when the lens 20 is located at different positions within the lens barrel 30, the degree of deformation during temperature changes may vary due to factors such as material differences, structural characteristics, and distance from the heat source. By setting multiple support members 10 with different coefficients of thermal expansion, each support member 10 can produce a deformation that matches the corresponding part of the lens 20 during temperature changes, thereby more precisely limiting the deformation of the lens 20, further improving the performance stability of the lens during temperature changes, and reducing the occurrence of problems such as focus shift and blurring.

[0030] Optionally, the absolute values ​​of the coefficients of thermal expansion of the plurality of support members 10 increase from the light-incident side toward the direction away from the light-incident side.

[0031] It should be noted that the absolute value of the coefficient of thermal expansion reflects the degree of deformation of the support member 10 under temperature changes. That is, the larger the absolute value of the coefficient of thermal expansion of the support member 10, the greater the degree of deformation caused by temperature changes. In specific applications, the lens module is usually connected to the lens mount of the camera module. The lens 20 further away from the light-incident side is closer to the heat sources such as the image sensor 50 and voice coil motor in the camera module, and therefore the temperature rise is more obvious. That is, from the light-incident side to the direction away from the light-incident side, the temperature of multiple lenses 20 tends to rise. In this embodiment, since the absolute value of the coefficient of thermal expansion of multiple support members 10 increases from the light-incident side to the direction away from the light-incident side, the temperature and deformation gradient of multiple lenses 20 can be matched. This can more accurately suppress the difference in deformation caused by uneven temperature distribution within the lens barrel 30 of different lenses 20, and reduce various problems caused by uneven deformation of different lenses 20.

[0032] Optionally, the coefficient of thermal expansion of the lens 20 is positive, and the coefficient of thermal expansion of the support 10 is negative. The material of the support 10 includes Sc2W3O. 12 At least one of ZrV2O7 and polymer-based composite materials.

[0033] In this embodiment, the coefficient of thermal expansion of the lens 20 is positive, matching the commonly used lens 20 structure. Therefore, the existing technology can be directly used in the selection of lens 20 materials, reducing the design difficulty of the lens 20. The coefficient of thermal expansion of the support 10 is negative, so that the lens 20 can shrink and deform while it is heated and expanded, thereby suppressing the expansion of the lens 20 along the lens module axis and optimizing the problems of temperature drift, focus shift, and defocus blur caused by temperature changes in the lens module.

[0034] Among them, Sc2W3O 12ZrV2O7 is a typical negative thermal expansion material (NTE material), and Sc2W3O 12 The coefficient of thermal expansion of the support 10 can reach -8.7 ppm / ℃, which is more compatible with the common coefficient of thermal expansion of lens 20 (about 6-10 ppm / ℃), thus enabling more targeted deformation suppression. ZrV2O7, on the other hand, has a coefficient of thermal expansion of -12.5 ppm / ℃. Due to its larger absolute value, it can achieve higher temperature drift compensation efficiency. In specific applications, polymer-based composite materials can achieve a negative coefficient of thermal expansion by selecting appropriate polymer matrices and reinforcing phases and adjusting their proportions and preparation processes. This material offers high design flexibility, allowing for precise control of the coefficient of thermal expansion of the support 10 according to the specific needs of the lens, ensuring a better match with the thermal expansion characteristics of lens 20. For example, in some optional embodiments of this application, polyimide + carbon nanotube composite material can be used as the material for the support 10, controlling its coefficient of thermal expansion within the range of -5 to -15 ppm / ℃. Alternatively, ZrV2O7-PI composite material can be used. This application does not limit the specific type of composite material used.

[0035] Optionally, the lens module also includes a lens barrel 30, with a support member 10 connected to the inner wall of the lens barrel 30, and a preload force between the support member 10 and the inner wall of the lens barrel 30.

[0036] It should be noted that in practical applications, there may be an assembly gap between the support member 10 and the lens barrel 30 during assembly. In the presence of such an assembly gap, the support member 10 will lag in compensating for the temperature drift of the lens 20 during temperature changes, affecting the sensitivity of the support member 10 in compensating for the temperature drift of the lens 20. Specifically, when the temperature inside the lens barrel 30 changes, if there is an assembly gap at the beginning of the assembly, and the support member 10 is free to deform without being restricted by the lens barrel 30, then the deformation of the support member 10 may be absorbed by the assembly gap first, and thus cannot effectively compensate for the deformation of the lens 20.

[0037] In this embodiment, by applying a preload between the support member 10 and the inner wall of the lens barrel 30, the deformation of the support member 10 is constrained by the lens barrel 30. Therefore, the deformation of the support member 10 can more efficiently compensate for the deformation of the lens 20, achieving more precise suppression of the deformation of the lens 20. Furthermore, with a preload between the support member 10 and the inner wall of the lens barrel 30, the contact between them is tighter. This prevents relative displacement or loosening between the support member 10 and the lens barrel 30 in vibration and impact environments, maintaining the stability of the lens 20 and thus helping to maintain the optical accuracy of the lens module.

[0038] In specific applications, the machining dimensions of the support component 10 can be controlled to keep the tolerance within ±10μm, thereby ensuring the accuracy of temperature drift compensation for the lens module.

[0039] like Figure 7 As shown, the lens module also includes a piezoelectric actuator 40, which is connected to the support member 10. The piezoelectric actuator 40 is used to generate deformation along the axial direction of the lens module when energized, and drives the support member 10 to generate deformation along the axial direction of the lens module. In this way, the piezoelectric actuator 40 can serve as an adjustment component to eliminate residual defocus in the lens module and improve the temperature drift compensation accuracy of the entire lens module.

[0040] It should be noted that different batches of the support member 10 and lens 20 may have different coefficients of thermal expansion. Under temperature changes, even if the support member 10 provides some temperature drift compensation for the lens 20, residual defocus may still occur. The amount of defocus is essentially the axial offset of the image plane relative to the sensor plane. In this embodiment, by adding a piezoelectric actuator 40, when the piezoelectric actuator 40 is energized, it will deform along the axial direction of the lens module, thereby driving the support member 10 connected to it to deform along the axial direction of the lens module. In this process, the piezoelectric actuator 40 compensates for the temperature drift of the lens 20, which is essentially changing the optical path by finely adjusting the spacing of the lens 20, thereby accurately pulling the image plane back to the sensor plane. The specific compensation process is as follows: Voltage drive: When the piezoelectric actuator 40 is energized, a voltage is applied, and the piezoelectric actuator 40 extends or contracts along the axial direction of the lens module. Stress transmission: The elongation or contraction of the piezoelectric actuator 40 in the lens module axial direction is transmitted to the support member 10 through the adhesive layer, and a pressure or tension in the lens module axial direction is applied to the support member 10. Finally, the support member 10 applies the corresponding force to the lens 20, thereby completing the compensation.

[0041] In practical applications, the piezoelectric actuator 40 and the support 10 can be bonded together with a very thin layer of high-rigidity, high-thermal-conductivity epoxy resin adhesive (such as silver paste). The two are fixed as a rigid whole within the lens barrel 30. This ensures both mechanical and thermal coupling between them; that is, the displacement of the piezoelectric actuator 40 can be transmitted to the support 10 without loss, and the support 10 can quickly sense temperature changes within the lens barrel 30. Figure 7 As shown, the piezoelectric actuator 40 can be electrically connected to the printed circuit board 70 of the camera module to supply power to the piezoelectric actuator 40. In practical applications, the piezoelectric actuator 40 can be a piezoelectric ceramic actuator, and the piezoelectric actuator 40 can be electrically connected to the printed circuit board 70 of the camera module via a flexible circuit board 41.

[0042] Optionally, when there are multiple support members 10, the support member 10 away from the incident light side is the target support member 10, and the piezoelectric actuator 40 is connected to the side of the target support member 10 away from the incident light.

[0043] As mentioned earlier, in the camera module, the lens 20 and support 10, which are furthest from the light-incident side, are closer to heat sources such as the image sensor 50 and voice coil motor. The heat emitted by these heat sources is... Figure 7 The direction indicated by the middle arrow is upward. Near the heat source, the lens 20 experiences the most significant thermal deformation, acting as an "amplifier" for the compensation effect, resulting in the highest calibration efficiency. Furthermore, in practical applications, it has been found that even small changes in the spacing between the lenses 20 on this side have the most significant impact on the focal point. In this embodiment, the support 10 furthest from the incident light side is defined as the target support 10, and the piezoelectric actuator 40 is connected to the side of the target support 10 closest to the heat source. This maximizes calibration efficiency and improves the accuracy of eliminating residual defocus. Additionally, the side of the lens module closest to the image sensor 50 typically has more space, making it easier to arrange the piezoelectric actuator 40 and reducing spatial layout complexity.

[0044] Optionally, the lens module also includes a drive module with a voltage memory function. The drive module is electrically connected to the piezoelectric actuator 40 and is used to apply a preset voltage to the piezoelectric actuator 40 when it is at a preset temperature, wherein the preset temperature and the preset voltage correspond one-to-one.

[0045] In this embodiment, the driving module has a voltage memory function, and the preset temperature corresponds one-to-one with the preset voltage. Thus, when the lens module has different residual defocus under different temperature changes, the piezoelectric actuator 40 is driven to deform accordingly by the preset voltage related to the temperature, and the piezoelectric actuator 40 automatically compensates for the deformation of the lens 20, thereby improving the accuracy and sensitivity of temperature drift compensation for the lens 20.

[0046] In specific applications, the coordination between the drive module and the piezoelectric actuator 40 includes initial calibration and operational compensation. The working process between the drive module and the piezoelectric actuator 40 in these two processes is as follows: First, during the initial calibration process, the assembled camera module is placed in a high-temperature test chamber, and the temperature of the test chamber is adjusted to a preset temperature (e.g., 60°C) to perform the "memory" writing process. This process is completed before the camera module leaves the factory, and the specific steps are as follows: Step S101: Photograph the standard test chart using a high-temperature test chamber; Step S102: Measure its modulation transfer function (MTF) value through a high-temperature test chamber. At this time, even if the support 10 has passive temperature drift compensation for the lens 20, there may still be residual defocus (e.g., +3μm). Step S103: Send a control signal to the drive module of the lens module through the high temperature test chamber. The drive module applies a calibration voltage to the piezoelectric actuator 40 according to the control signal. The piezoelectric actuator 40 generates a precise axial displacement according to the inverse piezoelectric effect. This displacement will apply a pressure or tension along the axial direction of the lens module to the support member 10. The support member 10 transmits this force to the lens 20. Step S104: Monitor MTF in real time through the high temperature test chamber. When MTF reaches its peak value, it means that residual defocus has been eliminated. At this time, send a "write to memory" command to the drive module. After receiving the command, the drive module stops applying voltage. The corresponding voltage value at this time is the preset voltage at the preset temperature. The drive module records and stores the preset voltage to complete the "memory" writing process.

[0047] In step S102, applying a calibration voltage to the piezoelectric actuator 40 via the lens module's drive module ensures that the lens module can independently reproduce the calibration state within the test chamber even after leaving the high-temperature test chamber. The drive module may include a electrically erasable programmable read-only memory (EROM), in which the aforementioned preset voltage data can be stored. When the camera module is activated, the drive module can read the temperature data within the lens barrel 30 and apply the corresponding preset voltage stored in the EROM at that temperature to the piezoelectric actuator 40, thereby driving the piezoelectric actuator 40 to deform and thus deform the support member 10.

[0048] Secondly, the compensation process during the lens module's operation, namely the "memory" reading and restoration process, is as follows: Step S201: When the user is using the mobile phone normally, the camera module is powered on, and the driver module will immediately and automatically apply a preset voltage corresponding to the current temperature; Step S202: The piezoelectric actuator 40 instantly deforms to a state corresponding to the preset voltage, causing the support 10 to accurately reproduce the optimal "compensation shape" in the initial calibration process, thus completing the compensation for residual defocus.

[0049] In this embodiment, the piezoelectric actuator 40 works in conjunction with the support member 10. The support member 10 provides passive, rapid, and continuous real-time thermal compensation to cope with instantaneous temperature changes, while the piezoelectric actuator 40 provides active, precise, and discrete calibration values ​​to correct systematic deviations caused by material tolerances, machining errors, and assembly stresses.

[0050] In summary, the lens module provided in this application embodiment may include at least the following advantages: In this embodiment, the lens module includes a support member 10 and a lens 20. The support member 10 is provided with a support groove. Since the circumferential edge of the lens 20 is connected to the support groove of the support member 10, the support member 10 can support the lens 20 through the support groove, and the lens 20 can be kept stable during the operation of the lens module. In this embodiment, since the thermal expansion coefficient of the support member 10 and the thermal expansion coefficient of the lens 20 have opposite signs, when the lens 20 tends to deform under the same temperature change, the support member 10 can undergo opposite deformation under the same temperature change conditions. This can limit the deformation of the lens 20 to a certain extent through its own deformation, thereby reducing problems such as focus shift, defocus blur, and response lag caused by the temperature change of the lens 20. This ensures the performance stability during the temperature change process without increasing the complexity of the lens module.

[0051] This application also provides a camera module, including the lens module as described in any of the above embodiments.

[0052] Specifically, such as Figure 7 As shown, the camera module also includes an image sensor 50 and a lens mount 60. The lens mount 60 is connected to the light-incident side of the image sensor 50, and the lens module is connected to the side of the lens mount 60 that is circumferentially away from the image sensor 50. A printed circuit board 70 is provided on the side of the image sensor 50 away from the lens mount 60 for powering the image sensor 50. The piezoelectric actuator 40 in the lens module is electrically connected to the printed circuit board 70 through a flexible circuit board 41 to compensate for the defocus of the lens module when powered on.

[0053] In this embodiment, the lens module includes a support member 10 and a lens 20. The support member 10 is provided with a support groove. Since the circumferential edge of the lens 20 is connected to the support groove of the support member 10, the support member 10 can support the lens 20 through the support groove, and the lens 20 can be kept stable during the operation of the lens module. In this embodiment, since the thermal expansion coefficient of the support member 10 and the thermal expansion coefficient of the lens 20 have opposite signs, when the above-mentioned lens module is applied to the camera module in this embodiment, when the lens 20 tends to deform under the change of ambient temperature, the support member 10 can undergo opposite deformation under the same ambient temperature change conditions. This can limit the deformation of the lens 20 to a certain extent through its own deformation, thereby reducing problems such as focus shift, defocus blur, and response lag caused by changes in ambient temperature. Without increasing the complexity of the lens module, the performance stability during the process of ambient temperature change is guaranteed, and the performance of the camera module is improved.

[0054] This application provides an electronic device, including a lens module or camera module as described above.

[0055] It should be noted that in the embodiments of this application, the structure of the lens module or camera module is the same as that of the lens module or camera module in any of the above embodiments, and its beneficial effects are also similar, so it will not be described in detail here.

[0056] This application provides an electronic device, including a lens module or camera module as described in any of the preceding claims.

[0057] It should be noted that in the embodiments of this application, the structure of the lens module or camera module is the same as that of the lens module or camera module in any of the above embodiments, and its beneficial effects are also similar, so it will not be described in detail here.

[0058] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0059] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A lens module, characterized in that, The lens module includes a support member and a lens element. The support member is provided with a support groove, and the circumferential edge of the lens element is connected to the support groove. The coefficient of thermal expansion of the support member has the opposite sign to that of the coefficient of thermal expansion of the lens.

2. The lens module according to claim 1, characterized in that, The number of lenses is multiple, and the multiple lenses are spaced apart along the axial direction of the lens module. The support member is provided with multiple support grooves, and the multiple support grooves are spaced apart along the axial direction of the lens module. One lens is connected to one support groove.

3. The lens module according to claim 1, characterized in that, The number of the support members is multiple, and the multiple support members are spaced apart along the axial direction of the lens module. The multiple support members may have the same or different coefficients of thermal expansion.

4. The lens module according to claim 3, characterized in that, The absolute values ​​of the coefficients of thermal expansion of the plurality of support members increase from the light-incident side toward the direction away from the light-incident side.

5. The lens module according to any one of claims 1 to 4, characterized in that, The lens has a positive coefficient of thermal expansion, while the support has a negative coefficient of thermal expansion. The support is made of Sc2W3O. 12 At least one of ZrV2O7 and polymer-based composite materials.

6. The lens module according to any one of claims 1 to 4, characterized in that, The lens module also includes a lens barrel, the support member is connected to the inner wall of the lens barrel, and there is a preload force between the support member and the inner wall of the lens barrel.

7. The lens module according to any one of claims 1 to 4, characterized in that, The lens module also includes a piezoelectric actuator, which is bonded to the support member. The piezoelectric actuator is used to generate deformation along the axial direction of the lens module when energized, and to drive the support member to generate deformation along the axial direction of the lens module.

8. The lens module according to claim 7, characterized in that, When there are multiple supports, the support furthest from the incident light side is the target support, and the piezoelectric actuator is connected to the side of the target support furthest from the incident light.

9. The lens module according to claim 7, characterized in that, The lens module also includes a drive module with a voltage memory function. The drive module is electrically connected to the piezoelectric actuator and is used to apply a preset voltage to the piezoelectric actuator when it is at a preset temperature, wherein the preset temperature and the preset voltage correspond one-to-one.

10. An electronic device, characterized in that, Includes the lens module as described in any one of claims 1 to 9.

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