Optical lens, camera module and assembly method thereof

Abstract

The present invention provides an optical lens, comprising: a first lens component, which includes at least one first lens; a second lens component, which includes a second lens barrel and at least one second lens installed in the second lens barrel, the at least one first lens and the at least one second lens together constitute an imageable optical system, and the at least one first lens and the at least one second lens have at least one free-form surface lens; and a connecting medium, which is suitable for fixing the first lens component and the second lens component together. The present invention also provides a corresponding camera module and an optical lens and a camera module assembly method. The present invention can reduce the distortion of optical lenses with small size and large aperture, can reduce the total optical length of the camera module, can effectively avoid product defects caused by inaccurate positioning of the free-form surface lens in the rotation direction of the lens barrel, and can effectively improve the installation accuracy of the free-form surface lens.

Description

Technical Field

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

[0002] With the popularization of mobile electronic devices, the relevant technologies of camera modules used in mobile electronic devices to help users obtain images (such as videos or images) have been rapidly developed and improved, and in recent years, camera modules have been widely used in many fields such as medical treatment, security, industrial production, etc.

[0003] In order to meet the increasingly broad market demand, high pixel, small size, and large aperture are the irreversible development trend of existing camera modules. Large aperture lenses can bring a large field of view, but this also causes the problem of longer optical length of the lens and larger field of view distortion. For example, the distortion of a mobile phone lens with a 130° field of view is >10%. In the field of small-size optical devices, the above problems will be more prominent and difficult to solve.

[0004] In recent years, free-form technology has become increasingly mature, and lenses with free-form surfaces can be obtained using free-form technology. Based on free-form technology, the progressive multifocal surface can be processed on the front or back surface of the lens through free-form design software during optical design, and then the complex surface can be processed by, for example, a lathe. At present, free-form technology has been widely used in the high-end eyeglass industry. If free-form lenses are used in the field of small-sized optical devices (such as mobile phone camera modules), it will help reduce the distortion of large field angles and reduce the total optical length of the camera module to a certain extent. Taking the above-mentioned 130° field angle mobile phone lens as an example, using free-form lenses is expected to reduce distortion to less than 2%. If free-form lenses are used as ordinary autofocus modules, the total optical length can be reduced by about 10%, the MTF design value can be increased by 8%, and the distortion can be reduced to less than 1%. In other words, free-form lenses can reduce or minimize the aberrations of the optical system, realize the functions of correcting aberrations and reducing distortion, and can also reduce the total optical length and / or volume of the module.

[0005] However, a free-form surface is a complex aspheric surface, which is irregular and asymmetric in most cases, and has multiple axes of symmetry. In the field of small-sized optical devices (such as the field of mobile phone camera modules), typical optical lenses on the market are currently assembled by embedding them piece by piece. Specifically, a lens barrel with a stepped bearing surface on the inside is prepared in advance, and then each lens is embedded into the stepped bearing surface on the inside of the lens barrel piece by piece to obtain a complete optical lens. Due to the limitations of the installation process, the lens surface selected in the lens barrel is usually a spherical or aspherical surface with rotational symmetry. If a free-form surface lens is used, the assembly process of the traditional compact camera module lens cannot be accurately installed. Because in an optical system with a free-form surface lens, it is difficult to find the optical center because the non-rotationally symmetric free-form surface lens does not have a single optical axis to make it symmetrical, and the optical axis alignment and correction problems cannot be controlled. The lens surface size of the camera module is often less than 0.7cm. In the installation of small-sized lenses, higher installation requirements and faster installation capabilities are required. The above problems make it difficult for free-form surface lenses to be applied to compact camera modules. Summary of the invention

[0006] The present invention aims to provide a solution that overcomes at least one of the drawbacks of the prior art.

[0007] According to one aspect of the present invention, there is provided an optical lens, comprising: a first lens component, which includes at least one first lens; a second lens component, which includes a second lens barrel and at least one second lens installed in the second lens barrel, the at least one first lens and the at least one second lens together constitute an imageable optical system, and the at least one first lens and the at least one second lens have at least one free-form surface lens; and a connecting medium, suitable for fixing the first lens component and the second lens component together.

[0008] In one embodiment, the connecting medium is a glue material, which is suitable for supporting and fixing the first lens component and the second lens component, and making the relative position of the first lens component and the second lens component maintain the relative position determined by active calibration. In another embodiment, the connecting medium can also be a welding medium.

[0009] In one embodiment, an axis of the first lens component and an axis of the second lens component have a non-zero angle therebetween.

[0010] In one embodiment, the number of the first lenses is one, and the first lens is a free-form lens.

[0011] In one embodiment, the number of the at least one second lens is plural, and the at least one second lens includes a free-form surface lens.

[0012] In one embodiment, the at least one first lens has a free-form surface lens, and the at least one second lens also has a free-form surface lens.

[0013] In one embodiment, the first lens component further includes a first lens barrel, and the at least one first lens is mounted on an inner side of the first lens barrel.

[0014] In one embodiment, the first lens component and / or the second lens component has an identification characterizing the surface direction information of the free-form surface lens contained therein.

[0015] In one embodiment, the free-form surface lens has a reference plane perpendicular to its thickness direction, the free-form surface lens has a reference direction within the reference plane, and the first lens component and / or the second lens component has an identification of the reference direction to characterize the surface direction information of the free-form surface lens.

[0016] In one embodiment, the connecting medium is a glue material, which is suitable for supporting and fixing the first lens component and the second lens component, and making the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design no more than 0.05 degrees.

[0017] In one embodiment, there is a gap between the first lens component and the second lens component along the optical axis direction of the optical lens.

[0018] According to another aspect of the present invention, a camera module is provided, comprising the optical lens described in any one of the aforementioned embodiments.

[0019] According to another aspect of the present invention, there is also provided an optical lens assembly method, comprising: preparing a first lens component and a second lens component to be separated from each other, wherein the first lens component comprises at least one first lens, the second lens component comprises a second lens barrel and at least one second lens installed in the second lens barrel, and the at least one first lens and the at least one second lens have at least one free-form surface lens; pre-positioning the first lens component and the second lens component so that the at least one first lens and the at least one second lens together constitute an imageable optical system; adjusting and determining the relative position of the first lens component and the second lens component based on active calibration; and bonding the first lens component and the second lens component by adhesive material so that the first lens component and the second lens component are fixed and maintained at the relative position determined by the active calibration.

[0020] In one embodiment, in the preparation step, the at least one first lens has at least one free-form surface lens, and the at least one second lens also has at least one free-form surface lens.

[0021] In one embodiment, the active calibration includes: adjusting and determining the relative position relationship between the first lens component and the second lens component by clamping or adsorbing the first lens component and / or the second lens component according to the measured resolution of the optical system.

[0022] In one embodiment, the active calibration also includes: adjusting the relative position relationship between the first lens component and the second lens component so that the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design is no more than 0.05 degrees, wherein the reference direction is used to characterize the surface direction information of the free-form surface lens.

[0023] In one embodiment, the active calibration further comprises: moving the first lens component along an adjustment plane, and determining the relative position between the first lens component and the second lens component in a moving direction along the plane according to a measured resolution of the optical system, wherein the movement comprises a rotation on the adjustment plane.

[0024] In one embodiment, in the active calibration step, the movement further includes a translation on the adjustment plane.

[0025] In one embodiment, the active calibration further comprises: adjusting and determining an angle between an axis of the first lens component and an axis of the second lens component according to a measured resolution of the optical system.

[0026] In one embodiment, the active calibration further includes: moving the first lens component along a direction perpendicular to the adjustment plane, and determining the relative position between the first lens component and the second lens component in the direction perpendicular to the adjustment plane based on the measured resolution of the optical system.

[0027] In one embodiment, in the preparation step, the first lens component further includes a first lens barrel, and the at least one first lens is mounted on an inner side of the first lens barrel.

[0028] In one embodiment, in the pre-positioning step, a gap is provided between the bottom surface of the first lens component and the top surface of the second lens component; and in the bonding step, the adhesive is arranged in the gap.

[0029] According to another aspect of the present invention, there is also provided a camera module assembly method, comprising: assembling an optical lens using the optical lens assembly method of any one of the aforementioned embodiments; and assembling a camera module based on the optical lens.

[0030] Compared with the prior art, the present invention has at least one of the following technical effects:

[0031] 1. The present invention can reduce distortion by applying a free-form surface lens to an optical lens of small size and large aperture.

[0032] 2. The present invention can reduce distortion by applying free-form surface lenses to high-pixel, small-size, and large-aperture camera modules.

[0033] 3. The present invention can reduce the total optical length of the camera module, thereby reducing the volume of the camera module.

[0034] 4. The present invention can effectively avoid product defects caused by the undesired rotation of the free-form surface lens in the lens barrel or inaccurate positioning of the rotation direction during assembly. The sensitivity of free-form surface lens assembly errors, especially rotation errors, is very high. If an optical lens or camera module containing a free-form surface lens is assembled based on traditional processes, the free-form surface lens is prone to undesired rotation or inaccurate positioning of the rotation direction in the lens barrel, which in turn leads to problems such as substandard product imaging quality or even failure to image. The present invention can effectively solve the above problems.

[0035] 5. The present invention can effectively improve the installation accuracy of free-form surface lenses in the field of small-sized optical devices, thereby improving the imaging quality of optical lenses or camera modules.

[0036] 6. The present invention can effectively improve the production efficiency of optical lenses or camera modules containing free-form surface lenses and increase the product yield, and is suitable for mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Exemplary embodiments are shown in the referenced drawings. The embodiments and drawings disclosed herein are to be considered illustrative rather than restrictive.

[0038] Figure 1 A cross-sectional schematic diagram of an optical lens 1000 according to an embodiment of the present invention is shown;

[0039] Figure 2 A three-dimensional schematic diagram of a free-form surface lens in one embodiment of the present invention is shown;

[0040] Figure 3 A cross-sectional schematic diagram of a camera module 2000 according to an embodiment of the present invention is shown;

[0041] Figure 4FIG. 1 is a cross-sectional schematic diagram of an optical lens 1000a according to another embodiment of the present invention;

[0042] Figure 5 Shown based on Figure 4 A cross-sectional schematic diagram of a photosensitive component 2000a of an optical lens 1000a;

[0043] Figure 6 FIG. 1 is a cross-sectional schematic diagram of an optical lens 1000b according to another embodiment of the present invention;

[0044] Figure 7 Shown based on Figure 6 A cross-sectional schematic diagram of a photosensitive component 2000b of an optical lens 1000b;

[0045] Figure 8 A flow chart showing an optical lens assembly method in one embodiment of the present invention is shown;

[0046] Figure 9a The relative position adjustment method in active calibration in one embodiment of the present invention is shown;

[0047] Figure 9b shows the rotation adjustment in active calibration of another embodiment of the present invention;

[0048] Fig.9c A relative position adjustment method with added v and w direction adjustments in active calibration of yet another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0049] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0050] It should be noted that in this specification, the expressions of first, second, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the feature. Therefore, without departing from the teaching of this application, the first subject discussed below can also be referred to as the second subject.

[0051] In the drawings, the thickness, size and shape of objects have been slightly exaggerated for ease of explanation. The drawings are only examples and are not drawn strictly to scale.

[0052] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, wholes, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, parts and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0053] As used herein, the terms "substantially," "approximately," and similar terms are used as terms of approximation, not degree, and are intended to account for the inherent variations in measurements or calculations that would be recognized by those of ordinary skill in the art.

[0054] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0055] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0056] Figure 1 A cross-sectional schematic diagram of an optical lens 1000 according to an embodiment of the present invention is shown. The optical lens 1000 includes a first lens component 100, a second lens component 200, and a glue material (not shown in the figure) for bonding the first lens component 100 and the second lens component 200 together. The first lens component 100 includes a first lens barrel 101 and a first lens 102, and the first lens 102 is a free-form lens. The second lens component 200 includes a second lens barrel 201 and five second lenses 202. The glue material is arranged in a gap 400 between the first lens component 100 and the second lens component 200 to fix the first lens component 100 and the second lens component 200 together. In this embodiment, the glue material supports and fixes the first lens component and the second lens component, and enables the relative position of the first lens component and the second lens component to maintain the relative position determined by active calibration.

[0057] In this embodiment, the free-form lens has a complex optical surface formed by processing based on the free-form technology. The complex optical surface can be obtained by, for example, designing a progressive multi-focal surface on the front or back surface of the lens through free-form design software during optical design, and then processing it through steps such as fine grinding and polishing on a high-precision CNC lathe. Figure 2 FIG. 1 shows a three-dimensional schematic diagram of a free-form surface lens in one embodiment of the present invention. Figure 2 It can be seen that the free-form surface is a complex aspheric surface, which is irregular and asymmetric in most cases. For a free-form surface lens, it has a strong directionality on a plane perpendicular to its thickness direction. In this embodiment, the relative position relationship between the first lens component 100 and the second lens component 200 can be adjusted in the active calibration stage to make the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design no more than 0.05 degrees (wherein the reference direction is used to characterize the surface direction information of the free-form surface lens), and then the first lens component 100 and the second lens component 200 are supported and fixed by the glue material located in the gap 400, so that the relative position of the first lens component 100 and the second lens component 200 remains the relative position determined by the active calibration, thereby ensuring the imaging quality of the optical lens.

[0058] In contrast, in the traditional optical lens assembly process, multiple lenses are assembled in the same lens barrel. Moreover, the non-rotationally symmetrical free-form surface lenses do not have the inherent property of optical axis symmetry, that is, they cannot rely on the optical axis of the lens for assembly positioning, adjustment and other operations, resulting in great difficulty in assembly, especially in the traditional process. The rotational positioning of the free-form surface lenses in the lens barrel is very difficult. In other words, the sensitivity of free-form surface lens assembly errors, especially rotational errors, is very high. If an optical lens or camera module containing a free-form surface lens is assembled based on the traditional process, the free-form surface lens is prone to unexpected rotation or inaccurate positioning of the rotation direction in the lens barrel, which in turn leads to problems such as substandard product imaging quality or even failure to image.

[0059] Further, Figure 3 FIG. 2 is a cross-sectional schematic diagram of a camera module 2000 according to an embodiment of the present invention. The camera module 2000 includes: Figure 1The optical lens 1000 and the photosensitive component 300 shown in the figure. The photosensitive component 300 includes a circuit board 301, a photosensitive chip 302 mounted on the circuit board 301, a cylindrical support body 303 mounted on the circuit board 301 and surrounding the photosensitive chip, and a color filter 304 mounted on the cylindrical support body 303. Further, the second lens component 200 may also include a motor, and the second lens barrel 201 may be mounted in a carrier of the motor. The motor is mounted on the top surface of the cylindrical support body 303 to fix the second lens component 200 and the photosensitive component 300 together. It should be noted that in other embodiments of the present invention, the motor may also be replaced by other structures such as a cylindrical support body, or it may also be cancelled and the second lens barrel 201 may be directly mounted on the top surface of the cylindrical support body 303. It should be noted that in other embodiments, the motor may also be replaced by other types of optical actuators, such as SMA (shape memory alloy) actuators, MEMS actuators, etc. Among them, the optical actuator refers to a device used to cause the optical lens to move relative to the photosensitive chip.

[0060] The above-mentioned embodiments can reduce distortion by applying the free-form surface lens to a small-sized, large-aperture optical lens, and can reduce distortion by applying the free-form surface lens to a high-pixel, small-sized, large-aperture camera module; the total optical length of the camera module can be reduced, thereby reducing the volume of the camera module; and product defects caused by the free-form surface lens's unexpected rotation in the lens barrel or inaccurate positioning of the rotation direction during assembly can be effectively avoided.

[0061] Further, in one embodiment, the size of the gap 400 along the optical axis direction of the optical lens is 30-100 μm.

[0062] Further, Figure 4 FIG. 2 is a cross-sectional schematic diagram of an optical lens 1000a according to another embodiment of the present invention. Figure 4 As shown, this embodiment and Figure 1 The difference of the optical lens 1000 shown is that the second lens component 200 has a free-form surface lens 209. The first lens of the first lens component 100 is a conventional lens. Figure 5 Shown based on Figure 4 A schematic cross-sectional view of a photosensitive component 2000a of an optical lens 1000a.

[0063] Further, Figure 6 FIG. 1 is a cross-sectional schematic diagram of an optical lens 1000b according to another embodiment of the present invention. Figure 6 As shown, this embodiment and Figure 1The difference between the optical lens 1000 shown is that the first lens component 100 and the second lens component 200 respectively have free-form surface lenses 209a and 209b. Under this design, in the active calibration stage, the relative positions of the first lens component 100 and the second lens component 200 can be adjusted to make the surface directions of the free-form surface lenses 209a and 209b complementary, thereby better adjusting the actual imaging quality of the optical system. Further, Figure 7 Shown based on Figure 6 Since the relative positions of the first lens component 100 and the second lens component 200 can be adjusted during the active calibration phase to make the free-form surface lenses 209a and 209b complementary in their surface directions, the camera module can have better imaging quality.

[0064] It should be noted that in the above embodiment, the number of lenses of the first lens component and the second lens component can be adjusted as needed. For example, the number of lenses of the first lens component and the second lens component can be two and four, three and three, four and two, or five and one. The total number of lenses of the entire optical lens can also be adjusted as needed, for example, the total number of lenses of the optical lens can be six, five, or seven.

[0065] It should also be noted that the optical lens of the present application is not limited to two lens components. For example, the number of lens components can also be three or four, which is a number greater than two. When the number of lens components constituting the optical lens exceeds two, the two adjacent lens components can be respectively regarded as the first lens component and the second lens component described above. For example, when the number of lens components of the optical lens is three, the optical lens may include two first lens components and a second lens component located between the two first lens components, and all the first lenses of the two first lens components and all the second lenses of the one second lens component together constitute an imageable optical system for active calibration. When the number of lens components of the optical lens is four, the optical lens may include two first lens components and two second lens components, and they are arranged from top to bottom in the order of the first lens component, the second lens component, the first lens component, and the second lens component, and all the first lenses of the two first lens components and all the second lenses of the two second lens components together constitute an imageable optical system for active calibration. Other variations such as these are not described one by one in this article.

[0066] Further, Figure 8 FIG. 1 is a flow chart showing an optical lens assembly method in one embodiment of the present invention. Figure 8 , the method comprising:

[0067] Step 10, preparing a first lens component and a second lens component separated from each other, wherein the first lens component includes a first lens barrel and at least one first lens installed in the first lens barrel, and the second lens component includes a second lens barrel and at least one second lens installed in the second lens barrel. Among the first lens and the second lens, at least one free-form surface lens exists.

[0068] Step 20, pre-positioning the first lens component and the second lens component so that the at least one second lens and the at least one first lens together form an imageable optical system.

[0069] Step 30: adjusting and determining the relative position of the first lens component and the second lens component based on active calibration.

[0070] Step 40, bonding the first lens component and the second lens component by adhesive material. In this step, the first lens component and the second lens component are supported and fixed by the cured adhesive material, so that the relative position of the first lens component and the second lens component is maintained at the relative position determined by the active calibration.

[0071] Further, in one embodiment, before executing step 30, adhesive material may be applied to the gap between the first lens component and the second lens component, and then step 30 is executed to adjust and determine the relative position of the first lens component and the second lens component. After the relative position is determined, step 40 is executed to cure the adhesive material, so that the first lens component and the second lens component are supported by the cured adhesive material, and the relative position of the first lens component and the second lens component is maintained at the relative position determined by active calibration. In another embodiment, step 30 may be executed first to adjust and determine the relative position of the first lens component and the second lens component. After the relative position is determined, the first lens component (or the second lens component) is temporarily moved away, and then adhesive material is applied, and then the first lens component (or the second lens component) is moved back based on the determined relative position. Finally, the adhesive material is cured to maintain the relative position of the first lens component and the second lens component at the relative position determined by active calibration.

[0072] Furthermore, the active calibration described in the present application can adjust the relative position of the first lens component and the second lens component in multiple degrees of freedom. Figure 9aThe relative position adjustment method in active calibration in one embodiment of the present invention is shown. In this adjustment method, the first lens component (which can also be the first lens) can move relative to the second lens component along the x, y, and z directions (that is, the relative position adjustment in this embodiment has three degrees of freedom). The z direction is the direction along the optical axis, and the x and y directions are the directions perpendicular to the optical axis. The x and y directions are both in an adjustment plane P, and the translation in the adjustment plane P can be decomposed into two components in the x and y directions.

[0073] Figure 9b FIG. 2 shows the rotation adjustment in active calibration of another embodiment of the present invention. In this embodiment, the relative position adjustment has Figure 9a In addition to the three degrees of freedom, a rotational degree of freedom, i.e., adjustment in the r direction, is added. In this embodiment, the adjustment in the r direction is a rotation within the adjustment plane P, i.e., a rotation around an axis perpendicular to the adjustment plane P.

[0074] Further, Fig.9c The figure shows a relative position adjustment method with added v and w direction adjustments in the active calibration of another embodiment of the present invention. The v direction represents the rotation angle of the xoz plane, the w direction represents the rotation angle of the yoz plane, and the rotation angles of the v and w directions can be synthesized into a vector angle, which represents the overall tilt state. In other words, by adjusting the v and w directions, the tilt posture of the first lens component relative to the second lens component (that is, the tilt of the optical axis of the first lens component relative to the optical axis of the second lens component) can be adjusted.

[0075] The adjustment of the six degrees of freedom x, y, z, r, v, and w may affect the imaging quality of the optical system (for example, the resolution). In other embodiments of the present invention, the relative position adjustment method may be to adjust only any one of the six degrees of freedom, or a combination of any two or more thereof.

[0076] In particular, in one embodiment, the active calibration includes at least calibration in the r direction. Specifically, the active calibration step (step 30) includes: adjusting and determining the relative position relationship between the first lens component and the second lens component by clamping or adsorbing the first lens component and / or the second lens component according to the measured resolution of the optical system (in the present invention, the resolution can be obtained by the measured MTF curve or SFR curve, but the method for obtaining the resolution is not limited thereto). The first lens component is moved along the adjustment plane, and the relative position between the first lens and the second lens component in the moving direction along the plane is determined according to the measured resolution of the optical system, wherein the movement includes rotation on the adjustment plane, i.e., movement in the r direction. In this embodiment, the first lens component and / or the second lens component has an identifier that characterizes the surface direction information of the free-form surface lens contained therein.

[0077] In one embodiment, the free-form surface lens has a reference plane perpendicular to its thickness direction, the free-form surface lens has a reference direction in the reference plane, and the first lens component and / or the second lens component have an identification of the reference direction to characterize the surface direction information of the free-form surface lens. The free-form surface lens is very sensitive to rotational positioning in the reference plane, and in the active calibration stage, the first lens component and the second lens component are relatively moved and adjusted along the r direction, which can improve the installation accuracy of the actual reference direction of the free-form surface lens. For example, the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design can be made no more than 0.05 degrees, thereby obtaining a small-size, large-aperture optical lens or camera module with high imaging quality. In this embodiment, when the free-form surface lens is rotated and corrected relative to other lenses, the aberration adjustment data can be collected and obtained in real time and corrected, so that the lens and / or camera module with the free-form surface lens can obtain a better imaging effect. By adjusting, the optical system composed of the two lens components has better imaging performance, such as small distortion around the imaging and small aberration of the optical system. The adjustment index of active calibration can be set according to different requirements, so that the optical lens after active calibration with different adjustment indexes can meet different optical performances.

[0078] On the other hand, in the pre-positioning stage, the identification of the reference direction can help the free-form surface lens to quickly pre-position to the direction determined by the optical design, and then actively adjust based on the pre-positioning. This will help improve the production efficiency of the optical lens or camera module. In another embodiment, the surface direction of the free-form surface lens can also be machine-recognized based on machine vision technology, and the r direction is pre-positioned based on the recognition result, and then active adjustments are made based on the pre-positioning.

[0079] Furthermore, in one embodiment, in the active calibration step, the movement also includes translation on the adjustment plane, ie, movement in the x and y directions.

[0080] Furthermore, in one embodiment, the active calibration further comprises: adjusting and determining the angle between the axis of the first lens component and the axis of the second lens component according to the measured resolution of the optical system, that is, adjustment in the w and v directions. In the assembled optical lens or camera module, the axis of the first lens component and the axis of the second lens component may have a non-zero angle.

[0081] Furthermore, in one embodiment, the active calibration also includes: moving the first lens component along a direction perpendicular to the adjustment plane (i.e., adjustment in the z direction), and determining the relative position between the first lens component and the second lens component in the direction perpendicular to the adjustment plane based on the measured resolution of the optical system.

[0082] Further, in one embodiment, in the pre-positioning step (step 20), a gap is provided between the bottom surface of the first lens component and the top surface of the second lens component; and in the bonding step (step 40), the adhesive is arranged in the gap.

[0083] Further, in one embodiment, in the preparation step (step 10), the first lens component may not have a first lens barrel. For example, the first lens component may be composed of a single first lens. In the pre-positioning step (step 20), a gap is provided between the bottom surface of the first lens and the top surface of the second lens component; and in the bonding step (step 40), the adhesive is arranged in the gap. In this embodiment, the first lens may be formed by a plurality of sub-lenses that are interlocked to form an integral body. In this embodiment, the side and top surfaces of the non-optical surface of the first lens that are not used for imaging may form a light-shielding layer. The light-shielding layer may be formed by screen-printing a light-shielding material on the side and top surfaces of the first lens.

[0084] In one embodiment, in the active calibration step, the second lens component can be fixed, the first lens component can be clamped by a fixture, and the first lens component can be moved under the drive of a six-axis motion mechanism connected to the fixture, thereby achieving relative movement between the first lens component and the second lens component in the above six degrees of freedom. The fixture can be supported or partially supported on the side of the first lens component, thereby clamping the first lens component.

[0085] Furthermore, according to an embodiment of the present invention, a camera module assembly method is also provided, comprising: assembling an optical lens using the optical lens assembly method of any of the aforementioned embodiments, and then using the assembled optical lens to manufacture a camera module.

[0086] Further, according to another embodiment of the present invention, a flowchart of another camera module assembly method is provided, the method comprising:

[0087] Step 100, preparing a first lens component and a camera module component, wherein the camera module component includes a second lens component and a photosensitive module that are combined together, and the first lens component includes a first lens barrel and at least one first lens installed in the first lens barrel, and the second lens component includes a second lens barrel and at least one second lens installed in the second lens barrel. In addition, there is at least one free-form surface lens in the first lens and the second lens.

[0088] Step 200: pre-position the first lens component and the second lens component so that the at least one second lens and the at least one first lens together form an imageable optical system.

[0089] Step 300: adjusting and determining the relative position of the first lens component and the second lens component based on active calibration.

[0090] Step 400: bonding the first lens component and the second lens component by adhesive.

[0091] It can be seen that, compared with the previous embodiment, in this embodiment, the second lens component and the photosensitive module are first assembled together to form a camera module component, and then the camera module component is assembled with the first lens component to obtain a complete camera module. The process of assembling the camera module component with the first lens component can also have multiple variations, for example, the multiple embodiments of the optical lens assembly method described above can be referred to to realize the assembly of the camera module component with the first lens component.

[0092] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. An optical lens, characterized in that: include: A first lens component including at least one first lens element; A second lens component includes a second lens barrel and at least one second lens installed in the second lens barrel, wherein the at least one first lens and the at least one second lens together constitute an imageable optical system, and at least one of the at least one first lens and the at least one second lens has at least one free-form surface lens; as well as a connecting medium, adapted to fix the first lens component and the second lens component together, wherein an angle between an axis of the first lens component and an axis of the second lens component is non-zero; and At least one of the first lens component and the second lens component has an identification characterizing the surface direction information of the free-form surface lens contained therein, wherein the identification of the reference direction includes an identification for machine recognition.

2. The optical lens according to claim 1, characterized in that: The connecting medium is a glue material, which is suitable for supporting and fixing the first lens component and the second lens component, and making the relative position of the first lens component and the second lens component maintain the relative position determined by active calibration.

3. The optical lens according to claim 1, characterized in that: The number of the first lenses is one, and the first lens is a free-form surface lens.

4. The optical lens according to claim 1, characterized in that: The number of the at least one second lens is plural, and the at least one second lens includes a free-form surface lens.

5. The optical lens according to claim 1, characterized in that: The at least one first lens has a free-form surface lens, and the at least one second lens has a free-form surface lens.

6. The optical lens according to claim 1, characterized in that: The first lens component further includes a first lens barrel, and the at least one first lens is installed inside the first lens barrel.

7. The optical lens according to claim 1, characterized in that: The free-form surface lens has a reference plane perpendicular to its thickness direction, the free-form surface lens has the reference direction in the reference plane, and the first lens component and / or the second lens component have an identification of the reference direction to characterize the surface direction information of the free-form surface lens.

8. The optical lens according to claim 7, characterized in that: The connecting medium is a glue material, which is suitable for supporting and fixing the first lens component and the second lens component, and making the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design no more than 0.05 degrees.

9. The optical lens according to claim 1, characterized in that: There is a gap between the first lens component and the second lens component along the optical axis direction of the optical lens.

10. A camera module, characterized in that: Comprising the optical lens as described in any one of claims 1-9.

11. An optical lens assembly method, characterized in that: include: Prepare a first lens component and a second lens component to be separated from each other, wherein the first lens component includes at least one first lens, the second lens component includes a second lens barrel and at least one second lens installed in the second lens barrel, and the at least one first lens and the at least one second lens have at least one free-form surface lens; Pre-positioning the first lens component and the second lens component so that the at least one first lens and the at least one second lens together form an imageable optical system; adjusting and determining a relative position of the first lens component and the second lens component based on active calibration; as well as The first lens component and the second lens component are bonded by adhesive material so that the first lens component and the second lens component are fixed and maintained at a relative position determined by active calibration, wherein an angle between an axis of the first lens component and an axis of the second lens component is non-zero; and At least one of the first lens component and the second lens component has an identification characterizing the surface direction information of the free-form surface lens contained therein, wherein the identification of the reference direction includes an identification for machine recognition.

12. The optical lens assembly method according to claim 11, characterized in that: In the preparation step, at least one of the at least one first lens has at least one free-form surface lens, and at least one of the at least one second lens also has at least one free-form surface lens.

13. The optical lens assembly method according to claim 11, characterized in that: The active calibration includes: adjusting and determining the relative position relationship between the first lens component and the second lens component by clamping or adsorbing the first lens component and / or the second lens component according to the measured resolution of the optical system.

14. The optical lens assembly method according to claim 13, characterized in that: The active calibration also includes: by adjusting the relative position relationship between the first lens component and the second lens component, the difference between the actual reference direction of the free-form surface lens and the reference direction determined by the optical design is not greater than 0.05 degrees, wherein the reference direction is used to characterize the surface direction information of the free-form surface lens.

15. The optical lens assembly method according to claim 13, characterized in that: The active calibration also includes: moving the first lens component along the adjustment plane, and determining the relative position between the first lens and the second lens component in the moving direction along the plane according to the measured resolution of the optical system, wherein the movement includes rotation on the adjustment plane.

16. The optical lens assembly method according to claim 15, characterized in that: In the active calibration step, the movement further includes translation on the adjustment plane.

17. The optical lens assembly method according to claim 13, characterized in that: The active calibration further includes: adjusting and determining the angle between the axis of the first lens component and the axis of the second lens component according to the measured resolution of the optical system.

18. The optical lens assembly method according to claim 15, characterized in that: The active calibration further includes: moving the first lens component along a direction perpendicular to the adjustment plane, and determining a relative position between the first lens component and the second lens component in the direction perpendicular to the adjustment plane according to a measured resolution of the optical system.

19. The optical lens assembly method according to claim 14, characterized in that: In the preparation step, the first lens component further includes a first lens barrel, and the at least one first lens is installed on the inner side of the first lens barrel.

20. The optical lens assembly method according to claim 14, characterized in that: In the pre-positioning step, a gap is provided between the bottom surface of the first lens component and the top surface of the second lens component; and In the bonding step, the adhesive material is arranged in the gap.

21. A camera module assembly method, characterized in that: Assembling an optical lens using the optical lens assembly method according to any one of claims 11 to 20; and A camera module is assembled based on the optical lens.

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