Film attaching method

Abstract

This application relates to the field of film bonding technology, and its embodiments provide a film bonding method. In this method, by hot-pressing the first optical film before determining the target position of the second optical film, the deformation of the first optical film caused by hot-pressing can be compensated by adjusting the position of the second optical film when determining the target position of the second optical film. This avoids the situation where the optical axis shifts due to hot-pressing the first optical film after determining the target position of the second optical film, thus improving the optical defects of the lens.

Description

Technical Field

[0001] This application relates to the field of film bonding technology, and in particular to a film bonding method. Background Technology

[0002] In related technologies, multiple optical films need to be bonded to the lens, and the relative positions between the optical films need to be corrected to improve the lens's imaging effect. Optical defects can easily occur during this process. Summary of the Invention

[0003] Therefore, it is necessary to provide a coating method to improve the optical defects of lenses.

[0004] This application provides a film application method for a lens, wherein the lens has a first curved surface and a second curved surface disposed opposite to each other, the first curved surface being a concave surface recessed toward the second curved surface, and the second curved surface being a convex surface protruding away from the first curved surface; the film application method includes:

[0005] The first optical film is bonded to the first curved surface by a hot-pressing process, and the first optical parameters of the bonded first optical film are obtained; the first optical parameters include the polarization angle.

[0006] The second optical film is aligned with the second curved surface, and the second optical parameters of the aligned second optical film are obtained; the second optical parameters include the optical axis angle.

[0007] Based on the first optical parameters and the second optical parameters, determine the target position where the second optical film is attached to the second curved surface;

[0008] The second optical film is attached to the target location.

[0009] In one embodiment, the step of attaching the first optical film to the first curved surface via a hot-pressing process specifically includes:

[0010] The first optical film is heated to soften it; wherein the first optical film is located on the first curved surface;

[0011] The softened first optical film is pressed onto the first curved surface of the lens.

[0012] In one embodiment, heating the first optical film specifically includes:

[0013] On the side of the first optical film that is away from the lens, the first optical film is heated in a preset manner;

[0014] The preset method includes either a contact heating method or a non-contact heating method.

[0015] In one embodiment, the film application method further includes evacuating the first optical film and the lens during the hot pressing process.

[0016] In one embodiment, obtaining the first optical parameters of the bonded first optical film specifically includes:

[0017] The laser is emitted onto the first optical film after bonding on the second curved surface side, and the laser passing through the first optical film and the lens is received.

[0018] A third optical parameter is obtained for the laser light passing through the first optical film and the lens; the third optical parameter includes the grayscale value of the laser spot.

[0019] The first optical parameters of the first optical film after lamination are determined based on the third optical parameters.

[0020] In one embodiment, determining the first optical parameters of the bonded first optical film based on the third optical parameters specifically includes:

[0021] The laser is emitted at a varying polarization angle to the first optical film after bonding, and the laser passing through the first optical film and the lens is received.

[0022] Obtain the third optical parameters of the current laser passing through the first optical film and the lens;

[0023] If the third optical parameter of the current laser satisfies the first preset condition, then the polarization angle corresponding to the current laser is taken as the polarization angle of the first optical film.

[0024] In one embodiment, in the step of emitting laser light onto the bonded first optical film at a varying laser polarization angle, the laser polarization angle varies continuously.

[0025] In one embodiment, obtaining the second optical parameters of the aligned second optical film specifically includes:

[0026] On the side of the second optical film opposite to the second curved surface after alignment, a laser is emitted toward the second optical film, and a laser that passes through the second optical film, the lens, and the first optical film is received.

[0027] Rotate the second optical film;

[0028] Obtain the fourth optical parameters of the current laser passing through the second optical film, the lens, and the first optical film;

[0029] If the fourth optical parameter of the current laser satisfies the second preset condition, then the angle of rotation of the second optical film corresponding to the current laser is taken as the optical axis angle of the second optical film.

[0030] In one embodiment, attaching the second optical film to the target location specifically includes:

[0031] The second optical film is attached to the target location using a rolling process.

[0032] In one embodiment, the surface shape of the first surface is any one of a freeform surface, an ellipsoid, a sphere, and a parabola; and / or

[0033] The second curved surface has an arc shape.

[0034] In one embodiment, the first optical film is any one of a polarizing film, a quarter-wave plate, a half-wave plate, an anti-reflective film, an anti-scratch film, a light scattering film, and an anti-fog film; and / or

[0035] The second optical film is any one of the following: polarizing film, quarter-wave plate, half-wave plate, anti-reflective film, scratch-resistant film, light scattering film, and anti-fog film.

[0036] In one embodiment, the first optical film has a multilayer structure.

[0037] In the above-described film application method, by hot-pressing the first optical film before determining the target position of the second optical film, the deformation of the first optical film caused by hot-pressing can be compensated by adjusting the position of the second optical film when determining the target position of the second optical film. This avoids the situation where the optical axis shifts due to hot-pressing the first optical film after determining the target position of the second optical film, thus improving alignment accuracy and mitigating optical defects in the lens.

[0038] Additional aspects and advantages of embodiments 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 embodiments of this application. Attached Figure Description

[0039] Figure 1 This is a schematic diagram showing the lens in an aligned state in one embodiment of the related technology;

[0040] Figure 2 This is a schematic diagram of the polarization angle when an unattached first optical film is placed at a target position in one embodiment of the related technology.

[0041] Figure 3 This is a schematic diagram of the polarization angle after hot-pressing and bonding the first optical film in one embodiment of the related technology.

[0042] Figure 4 This is a schematic flowchart of a film application method in one embodiment of this application;

[0043] Figure 5 This is a schematic diagram of the lens structure in one embodiment of this application;

[0044] Figure 6 This is a schematic diagram showing the lens in an aligned state according to one embodiment of this application;

[0045] Figure 7 This is a schematic diagram of the process of attaching the first optical film to the first curved surface by hot pressing in one embodiment of this application;

[0046] Figure 8 This is a schematic diagram of hot-pressing bonding of a first optical film in one embodiment of this application;

[0047] Figure 9 This is a schematic diagram of the process for obtaining the first optical parameters of the bonded first optical film in one embodiment of this application;

[0048] Figure 10 This is a schematic diagram of the process for obtaining the second optical parameters of the aligned second optical film in one embodiment of this application;

[0049] Figure 11 This is a schematic diagram of the polarization angle when the unattached second optical film is placed at the target position in one embodiment of this application;

[0050] Figure 12 This is a schematic diagram of the polarization angle after the second optical film is attached in one embodiment of this application;

[0051] Figure 13 This is a schematic diagram of the second optical film being attached in one embodiment of this application.

[0052] Brief explanation of component symbols:

[0053] 100: Lens 101: First Curved Surface

[0054] 102: Second curved surface; 200: First optical film

[0055] 300: Second optical film; 410: Laser emitting unit

[0056] 420: Laser receiving unit; 500: Hot pressing device

[0057] 510: Heating unit; 520: Pressurization unit

[0058] 530: Vacuum pumping unit; 600: Roller

[0059] x: laser a: cavity

[0060] F1: First Direction

[0061] M, N: Region Detailed Implementation

[0062] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific implementation methods of the embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the embodiments of this application. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application. The embodiments of this application can be implemented in many ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention. Therefore, the embodiments of this application are not limited to the specific embodiments disclosed below.

[0063] It is understood that the terms "first," "second," etc., used in this application may be used to describe various technical terms, but should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. However, unless specifically stated otherwise, these technical terms are not limited to these terms. These terms are only used to distinguish one technical term from another. For example, without departing from the scope of this application, the first surface and the second surface are different surfaces. In the description of embodiments of this application, "a plurality of" or "several" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0065] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the horizontal height of the first feature is higher than the horizontal height of the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0066] It should be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0067] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application and in its specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0068] In the field of optical imaging, coatings are often applied to optical lenses to improve their imaging performance. Taking AR (Augmented Reality) or VR (Virtual Reality) displays as examples, applying coatings to the lenses in display devices can create immersive visual effects, providing users with an immersive experience. To achieve even stronger enhanced display effects, curved lenses are typically used for imaging.

[0069] Figure 1 A schematic diagram of a lens 100 in an aligned state is shown in one embodiment of the related art; for ease of explanation, only the parts related to one embodiment of the related art are shown.

[0070] like Figure 1 As shown, one embodiment of the related technology provides a lens 100, which has a first curved surface 101 and a second curved surface 102 disposed opposite to each other along a first direction F1. The first curved surface 101 is a 3D curved surface recessed toward the second curved surface 102, and the second curved surface 102 is a 2.5D curved surface protruding away from the first curved surface 101. It can be understood that a 3D curved surface refers to a surface formed by deformation along a multi-axis curved surface, and a 2.5D curved surface refers to a surface formed by deformation along a single-axis curved surface. Typically, firstly, a second optical film 300 is attached to the second curved surface 102 of the lens 100; secondly, the position of the first optical film 200 is corrected by a laser emitting unit 410 and a laser receiving unit 420; and finally, the first optical film 200 is attached to the first curved surface 101 of the lens 100.

[0071] The inventors of this application have noted that, since the first curved surface 101 of the lens 100 is a 3D curved surface formed by deformation along a multi-axis surface, in order to better adhere the first optical film 200 to the first curved surface 101 of the lens 100, the first optical film 200 is usually heated to improve its extensibility. However, this heating of the first optical film 200 after calibration causes it to stretch and deform, resulting in a loss of optical axial accuracy of the adhered lens 100, and consequently, optical defects such as optical axis angle misalignment. Furthermore, the stretching deformation of the first optical film 200 is non-uniform and cannot be quantitatively compensated for. Figure 2 and Figure 3 For example, Figure 2 This diagram illustrates the polarization angle when an unattached first optical film 200 is placed at a target position, according to an embodiment of the related technology. Figure 3 A schematic diagram of the polarization angle after hot-pressing the first optical film 200 in one embodiment of the related technology is shown. It can be seen that the axial distribution of the corrected first optical film 200 is uniform. However, after the first optical film 200 is heated and then bonded to the first curved surface 101 of the lens 100, the axial distribution of the bonded first optical film 200 is not uniform, and the contrast is particularly significant in the corrected area M.

[0072] Based on this, the inventors of this application have improved the bonding process to avoid optical defects caused by changes in the axial direction of the optical film before and after correction. The bonding method provided in this application will be further described below with reference to the accompanying drawings and some embodiments.

[0073] Figure 4 A schematic flowchart of a film application method according to an embodiment of this application is shown; Figure 5 A schematic diagram of the structure of the lens 100 in one embodiment of this application is shown; Figure 6 A schematic diagram showing the lens 100 in an aligned state according to an embodiment of this application is shown; for ease of explanation, only the parts related to an embodiment of this application are shown.

[0074] In some embodiments, please refer to Figure 4 This application provides a film application method, which is applied to a lens 100. Figure 5 Taking the illustrated lens 100 as an example, the lens 100 has a first curved surface 101 and a second curved surface 102 disposed opposite to each other along a first direction F1. The first curved surface 101 is a concave surface recessed towards the second curved surface 102, and the second curved surface 102 is a convex surface protruding away from the first curved surface 101. The film application method includes the following steps:

[0075] S110. The first optical film 200 is bonded to the first curved surface 101 by hot pressing process, and the first optical parameters of the bonded first optical film 200 are obtained; the first optical parameters include the polarization angle.

[0076] Specifically, the hot-pressing process softens the first optical film 200 at a preset temperature to improve its ductility, facilitating its molding and bonding onto the first curved surface 101. During the hot-pressing process, the first optical film 200 undergoes stretching deformation due to heat. After bonding, the first optical film 200 reaches a stable state. Based on this, the first optical parameters of the bonded first optical film 200 are obtained, which facilitates the subsequent determination of the position of the second optical film 300.

[0077] It should be noted that the preset temperature can be determined based on the type and material of the first optical film 200, and this embodiment does not impose specific limitations on this. The optical parameters of the optical element include its optical power, optical cylinder power, optical cylinder axis, and optical center in the visual reference area. In this embodiment, the first optical parameter of the selected first optical film 200 includes the polarization angle, which is used to adjust the position of the subsequent second optical film 300. Of course, other optical parameters can also be combined or used for adjustment, depending on the specific adjustment process. This embodiment does not impose specific limitations on this, as long as the adjustment of the position of the second optical film 300 can be achieved.

[0078] S120: Align the second optical film 300 with the second curved surface 102 and obtain the second optical parameters of the aligned second optical film 300; the second optical parameters include the optical axis angle.

[0079] Specifically, such as Figure 6 As shown, after attaching the first optical film 200, the second optical film 300 is aligned with the second curved surface 102. The second optical parameters of the aligned second optical film 300 can be used as an initial reference to facilitate subsequent adjustments. The alignment position can be either where the central axis of the second optical film 300 coincides with the central axis of the lens 100, or it can be where they do not coincide. To facilitate subsequent adjustments, the aforementioned coincident position can be used; this embodiment does not impose specific limitations on this.

[0080] It is understood that in the embodiments of this application, the second optical parameters of the selected second optical film 300 include the optical axis angle. Of course, it can also be adjusted in combination with other optical parameters, which can be obtained according to the specific adjustment process. The embodiments of this application do not impose specific limitations on this.

[0081] S130. Determine the target position where the second optical film 300 is attached to the second curved surface 102 based on the first optical parameters and the second optical parameters.

[0082] Specifically, since the first optical parameter is the optical parameter of the deformed first optical film 200, and combined with the second optical parameter, adjustments can be made based on the position of the second optical film 300 to compensate for the polarization angle of the first optical film 200. By adjusting the position of the second optical film 300, different optical axis angles of the second optical film 300 can be obtained and matched with the polarization angle of the first optical film 200, thus obtaining the target position where the second optical film 300 is attached to the second curved surface 102.

[0083] It should be noted that before performing the step of "determining the target position of the second optical film 300 attached to the second curved surface 102", the required target position can be obtained by calculation based on the first optical parameters and the second optical parameters, or the position of the second optical film 300 can be adjusted to determine whether it is the required target position. The executing entities for the actions of "calculation" and "determination" can be the same entity or different entities; this application embodiment does not specifically limit this.

[0084] S140, attach the second optical film 300 to the target position.

[0085] Specifically, since the target position of the second optical film 300 attached to the second curved surface 102 of the lens 100 is determined, and the determination of the target position is carried out after the hot pressing process, it can compensate for the changes in the first optical parameters caused by the stretching deformation of the first optical film 200 during the hot pressing process.

[0086] Therefore, by hot-pressing the first optical film 200 before determining the target position of the second optical film 300, the deformation of the first optical film 200 caused by hot-pressing can be compensated by adjusting the position of the second optical film 300 when determining the target position of the second optical film 300. This avoids the situation where the optical axis shifts due to hot-pressing the first optical film 200 after determining the target position of the second optical film 300, thus improving alignment accuracy and mitigating optical defects in the lens 100.

[0087] Figure 7 The diagram shows a process flow diagram of attaching the first optical film 200 to the first curved surface 101 by hot pressing in one embodiment of this application; for ease of explanation, only the parts related to one embodiment of this application are shown.

[0088] In order to allow the first optical film 200 to better adhere to the first curved surface 101 of the lens 100, in some embodiments, such as Figure 7As shown, the process of attaching the first optical film 200 to the first curved surface 101 via hot pressing specifically includes:

[0089] S111. The first optical film 200 is heated to soften it; wherein the first optical film 200 is located on the first curved surface 101.

[0090] Specifically, when heating the first optical film 200, it can be heated on the side of the first optical film 200 away from the lens 100 using a preset method. The preset method includes either a contact heating method or a non-contact heating method. The contact heating method can use a metal pressure head with a preset temperature to heat the first optical film 200. The non-contact heating method can use infrared heating. The choice can be made according to the actual usage, and this embodiment does not impose specific limitations on this.

[0091] S112. Press the softened first optical film 200 onto the first curved surface 101 of the lens 100.

[0092] Specifically, by means of pressing, an adhesion pressure can be provided, so that the softened first optical film 200 can be adhered to the first curved surface 101 of the lens 100 by pressure.

[0093] Of course, in some other embodiments, a vacuum process can be performed on the first optical film 200 and the lens 100 before performing steps S111 and S112. In this way, the generation of air bubbles during the bonding process of the first optical film 200 and the lens 100 can be avoided, thus preventing optical defects.

[0094] Figure 8 A schematic diagram of the hot-press bonding of the first optical film 200 in one embodiment of this application is shown; for ease of explanation, only the parts related to one embodiment of this application are shown.

[0095] Specifically, such as Figure 8As shown, the first optical film 200 and the lens 100 can be placed in cavity a, with the first optical film 200 located on the first curved surface 101 of the lens 100. A vacuum is then applied to cavity a using a vacuum unit 530. During the vacuuming process, a negative pressure can be generated within cavity a, with a magnitude of 0.1 MPa. The magnitude of the negative pressure can be set according to actual usage, and this embodiment does not impose specific limitations on this. After vacuuming, the side of the first optical film 200 facing away from the lens 100 is heated and softened by a heating unit 510 to improve its extensibility, facilitating the adhesion of the planar first optical film 200 to the first curved surface 101 of the lens 100. Then, a pressurizing unit 520 located within cavity a applies pressure to the first optical film 200 on the side facing away from the lens 100. At this time, the pressure unit 520 can provide the attachment pressure, so that the first optical film 200 can be attached to the first curved surface 101 of the lens 100 by the attachment pressure.

[0096] Figure 9 A schematic flowchart illustrating the process of obtaining the first optical parameters of the bonded first optical film 200 in one embodiment of this application is shown; for ease of explanation, only the parts related to one embodiment of this application are shown.

[0097] To facilitate adjustment of the second optical film 300, such as Figure 9 As shown, in some embodiments, obtaining the first optical parameters of the bonded first optical film 200 specifically includes:

[0098] S113, emit laser x to the first optical film 200 after bonding on the second curved surface 102 side, and receive laser x passing through the first optical film 200 and the lens 100;

[0099] Specifically, in conjunction with reference Figure 6 A laser emitting unit 410 can be disposed on one side of the second curved surface 102 of the lens 100, and a laser receiving unit 420 can be disposed on one side of the first curved surface 101 of the lens 100. The laser emitting unit 410 and the laser receiving unit 420 are disposed opposite to each other along the first direction F1. A polarizer and an extinction plate can be disposed on the path of the laser x emitted by the laser emitting unit 410 before it reaches the lens 100, and the laser x emitted by the laser emitting unit 410 can be polarized into stable linearly polarized light by the polarizer and the extinction plate.

[0100] S114. Obtain the third optical parameters of the laser x passing through the first optical film 200 and the lens 100; the third optical parameters include the grayscale value of the laser spot;

[0101] Specifically, in conjunction with step S113, in step S114, the laser x, which is polarized into stable linearly polarized light, is then emitted sequentially through lens 100 and the first optical film 200 to laser receiving unit 420. Laser receiving unit 420 can detect the grayscale value of the laser x spot based on the received laser x, which is polarized into stable linearly polarized light. Optionally, laser receiving unit 420 can be a camera.

[0102] S115. Determine the first optical parameters of the first optical film 200 after bonding based on the third optical parameters.

[0103] Specifically, since the third optical parameter can reflect the linear polarization angle of the first optical film 200, in some embodiments, a laser x can be emitted towards the bonded first optical film 200 with a varying polarization angle of the laser x, and the laser x passing through the first optical film 200 and the lens 100 can be received. Then, the third optical parameter of the current laser x passing through the first optical film 200 and the lens 100 is obtained by the laser receiving unit 420. If the third optical parameter of the current laser x satisfies a first preset condition, the polarization angle corresponding to the current laser x is taken as the polarization angle of the first optical film 200.

[0104] In other words, the laser emitting unit 410 can be rotated so that when the grayscale value of the laser spot detected by the laser receiving unit 420 meets the first preset condition, the linear polarization angle of the light passing through the extinction plate is made consistent with the polarization angle of the first optical film 200. When the linear polarization angle of the light passing through the extinction plate is consistent with the polarization angle of the first optical film 200, the angle of rotation of the laser emitting unit 410 is the polarization angle of the first optical film 200.

[0105] It should be noted that the first preset condition refers to the situation where the grayscale value of the laser spot detected by the laser receiving unit 420 can characterize the situation where the linear polarization angle of the light passing through the extinction plate is consistent with the polarization angle of the first optical film 200. The specific value is determined according to the parameters of the laser x, and this application embodiment does not impose specific limitations on this.

[0106] Specifically, in some embodiments, when laser x is emitted onto the bonded first optical film 200 with a varying polarization angle, the polarization angle of laser x can be made to change continuously. This ensures that the grayscale value of the laser spot detected by the laser receiving unit 420 meets a first preset condition.

[0107] Figure 10 A schematic flowchart illustrating the process of obtaining the second optical parameters of the aligned second optical film 300 in one embodiment of this application is shown; for ease of explanation, only the parts related to one embodiment of this application are shown.

[0108] To further facilitate adjustments to the second optical film 300, such as Figure 10As shown, in some embodiments, obtaining the second optical parameters of the aligned second optical film 300 specifically includes:

[0109] S121. On the side of the second optical film 300 that is opposite to the second curved surface 102 after alignment, laser x is emitted toward the second optical film 300, and laser x passing through the second optical film 300, the lens 100 and the first optical film 200 is received.

[0110] Specifically, in conjunction with reference Figure 6 The relevant content in step S113 will not be repeated here.

[0111] S122, Rotating second optical film 300;

[0112] Specifically, the second optical film 300 can be rotated by a rotating device, and the laser receiving unit 420 receives the alternating bright and dark laser x.

[0113] S123. Obtain the fourth optical parameter of the current laser x passing through the second optical film 300, the lens 100 and the first optical film 200;

[0114] Specifically, in conjunction with step S123, in the steps of this application embodiment, the laser receiving unit 420 can detect changes in laser energy by alternating between light and dark.

[0115] S124. If the fourth optical parameter of the current laser x satisfies the second preset condition, then the rotation angle of the second optical film 300 corresponding to the current laser x is taken as the optical axis angle of the second optical film 300.

[0116] Specifically, the optical axis angle of the second optical film 300 is obtained based on the detected change in laser energy.

[0117] In this process, for example, if the polarization angle of the first optical film 200 is 1° before bonding, and the polarization angle becomes 2° after bonding due to stretching deformation, then before bonding the second optical film 300, adjusting and correcting the rotation angle of the second optical film 300 only requires an additional compensation of 1°. This process will not cause any additional offset to the angle between the first optical film 200 and the second optical film 300.

[0118] It should be noted that the second preset condition refers to the situation where the change in laser energy detected by the laser receiving unit 420 can characterize a good optical effect. The specific laser energy is determined according to the parameters of laser x and the optical film. This application embodiment does not impose specific limitations on this.

[0119] Therefore, based on the obtained first and second optical parameters, the polarization angle of the laser emitting unit 410, the polarization angle of the first optical film 200, and the optical axis angle of the second optical film 300 can be calculated to obtain a suitable matching angle between the polarization angle of the first optical film 200 and the optical axis angle of the second optical film 300. The target position of the second optical film 300 attached to the second curved surface 102 can be determined, and a lens 100 with good optical performance can be obtained.

[0120] It should be noted that in some of the above embodiments, the process of correcting the target position of the second optical film 300 is merely an exemplary process. Of course, other correction methods can also be used to obtain the target position of the second optical film 300, and this application embodiment does not impose specific limitations on this. The focus of this application embodiment is that the process of correcting the target position of the second optical film 300 is placed after the process of hot-pressing and bonding the first optical film 200, as long as the second optical film 300 can be corrected.

[0121] Figure 11 This illustration shows a schematic diagram of the polarization angle when the unattached second optical film 300 is placed at the target position in one embodiment of this application. Figure 12 This illustration shows a schematic diagram of the polarization angle after the second optical film 300 is attached in one embodiment of this application; for ease of explanation, only the parts related to one embodiment of this application are shown.

[0122] In conjunction with the film-applying methods provided in the above embodiments, since the second optical film 300 does not require application under heating and vacuum conditions, the second optical film 300 will not experience optical axial stretching deformation before and after correction, thus avoiding any loss of optical axis angle accuracy after application. Figure 11 and Figure 12 As shown, the axial distribution of the second optical film 300 is uniform before and after correction, and there is no change in the comparison at the corrected region N.

[0123] Figure 13 A schematic diagram of the second optical film 300 being bonded in one embodiment of this application is shown; for ease of explanation, only the parts relevant to one embodiment of this application are shown.

[0124] In some embodiments, such as Figure 13 As shown, the second optical film 300 can be attached to the target position using a roller 600 and a rolling process. This process can be carried out in an atmospheric environment.

[0125] In some embodiments, the surface shape of the first curved surface 101 of the lens 100 is any one of a freeform surface, an ellipsoid, a sphere, or a parabola. In other embodiments, the surface shape of the second curved surface 102 of the lens 100 is an arc surface. When the surface shape of the first curved surface 101 of the lens 100 is any one of a freeform surface, an ellipsoid, a sphere, or a parabola, since these surface shapes are multi-axis curved surfaces, a 3D curved surface is formed. Combined with the film application method provided in the embodiments of this application, the first optical film 200 can be well attached to the first curved surface 101 of the lens 100 using a hot pressing process. When the surface shape of the second curved surface 102 of the lens 100 is an arc surface, since the surface shape of the arc surface is a uniaxial curved surface, a 2.5D curved surface is formed. For the second curved surface 102 with a curvature of 2.5, there is no need to heat the second optical film 300 during the process of bonding the second optical film 300 onto it. The second optical film 300 can be well bonded onto the second curved surface 102 by using a rolling method, and the second optical film 300 will not be stretched or deformed before or after bonding.

[0126] In some embodiments, the first optical film 200 is any one of a polarizing film, a quarter-wave plate, a half-wave plate, an anti-reflective film, an anti-scratch film, a light scattering film, and an anti-fog film. In other embodiments, the first optical film 200 has a multilayer structure. In still other embodiments, the second optical film 300 is any one of a polarizing film, a quarter-wave plate, a half-wave plate, an anti-reflective film, an anti-scratch film, a light scattering film, and an anti-fog film.

[0127] In this way, the required type of optical film can be applied to the first curved surface 101 and the second curved surface 102 of the lens 100 according to the usage requirements. Because the film application method provided in this embodiment is used, while satisfying the multi-functional use of the lens 100, optical defects caused by applying multiple optical film layers can be avoided, thus meeting the user's needs.

[0128] It should be noted that the technical solutions described above can be implemented as independent embodiments or combined with each other as combined embodiments in actual implementation. The technical solutions described above are exemplary solutions, and the specific combination for implementation can be selected according to actual needs; this application does not impose specific limitations. Furthermore, the description of the embodiments of this application is based solely on the idea of ​​convenient explanation, and different embodiments are described in a corresponding order, such as according to the preset order required in the actual implementation process, rather than limiting the execution order between different embodiments. Accordingly, in actual implementation, if multiple embodiments provided by this application need to be implemented, it is not necessary to follow the execution order provided when describing the embodiments in this invention; instead, the execution order between different embodiments can be arranged according to needs.

[0129] It should be understood that although the steps in the flowchart are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowchart may include multiple steps or stages, which are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps.

[0130] In summary, in the film application method provided in this application embodiment, the first optical film 200 is first heat-pressed together, causing stretching deformation of the optical angle of the first optical film 200. Since the first optical film 200 does not require optical correction with the second optical film 300 at this time, the stretching deformation of the first optical film 200 has no effect. Although the first optical film 200 has already undergone stretching deformation during heat-pressing, it can be adjusted and corrected before the second optical film 300 is applied, which can compensate for the angle of the deformed first optical film 200. After the adjustment and correction are completed, since the application of the second optical film 300 does not require a heating process, the second optical film 300 will not be stretched or deformed during application. Thus, the optical axis misalignment caused by heat-pressing the first optical film 200 is avoided, the alignment accuracy is improved, and the optical defects of the lens 100 are improved.

[0131] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0132] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A film application method, applied to lenses, characterized in that, The lens has a first curved surface and a second curved surface arranged opposite to each other. The first curved surface is a concave surface that is recessed toward the direction of the second curved surface, and the second curved surface is a convex surface that is protruding away from the direction of the first curved surface. The film application method includes: The first optical film is bonded to the first curved surface by a hot-pressing process, and the first optical parameters of the bonded first optical film are obtained; the first optical parameters include the polarization angle. The second optical film is aligned with the second curved surface, and the second optical parameters of the aligned second optical film are obtained; the second optical parameters include the optical axis angle. Based on the first optical parameters and the second optical parameters, determine the target position where the second optical film is attached to the second curved surface; The second optical film is attached to the target location; Specifically, obtaining the first optical parameters of the first optical film after bonding includes: The laser is emitted onto the first optical film after bonding on the second curved surface side, and the laser passing through the first optical film and the lens is received. A third optical parameter is obtained for the laser light passing through the first optical film and the lens; the third optical parameter includes the grayscale value of the laser spot. The first optical parameters of the first optical film after lamination are determined based on the third optical parameters.

2. The film application method according to claim 1, characterized in that, The process of attaching the first optical film to the first curved surface via hot pressing specifically includes: The first optical film is heated to soften it; wherein the first optical film is located on the first curved surface; The softened first optical film is pressed onto the first curved surface of the lens.

3. The method of claim 2, wherein, The heating of the first optical film specifically includes: On the side of the first optical film that is away from the lens, the first optical film is heated in a preset manner; The preset method includes either a contact heating method or a non-contact heating method.

4. The method of claim 1, wherein, The film application method further includes evacuating the first optical film and the lens during the hot pressing process.

5. The method of claim 1, wherein, The step of determining the first optical parameters of the bonded first optical film based on the third optical parameters specifically includes: The laser is emitted at a varying polarization angle to the first optical film after bonding, and the laser passing through the first optical film and the lens is received. Obtain the third optical parameters of the current laser passing through the first optical film and the lens; If the third optical parameter of the current laser satisfies the first preset condition, then the polarization angle corresponding to the current laser is taken as the polarization angle of the first optical film; the first preset condition is that the grayscale value of the laser spot detected by the laser receiving unit indicates that the linear polarization angle after passing through the extinction plate is consistent with the polarization angle of the first optical film.

6. The method of claim 5, wherein, In the step of emitting laser light onto the first optical film after bonding with a varying laser polarization angle, the laser polarization angle varies continuously.

7. The method of claim 1, wherein, The acquisition of the second optical parameters of the aligned second optical film specifically includes: On the side of the second optical film opposite to the second curved surface after alignment, a laser is emitted toward the second optical film, and a laser that passes through the second optical film, the lens, and the first optical film is received. Rotate the second optical film; Obtain the fourth optical parameters of the current laser passing through the second optical film, the lens, and the first optical film; If the fourth optical parameter of the current laser satisfies the second preset condition, then the rotation angle of the second optical film corresponding to the current laser is taken as the optical axis angle of the second optical film; the second preset condition is that the change in laser energy detected by the laser receiving unit represents a good optical effect.

8. The method of claim 1, wherein, The step of attaching the second optical film to the target location specifically includes: The second optical film is attached to the target location using a rolling process.

9. The film application method according to any one of claims 1-8, characterized in that, The surface shape of the first surface is any one of the following: freeform surface, ellipsoid, sphere, parabola; and / or The second curved surface has an arc shape.

10. The film attaching method according to any one of claims 1 to 8, wherein The first optical film is any one of the following: a polarizing film, a quarter-wave plate, a half-wave plate, an anti-reflective film, an anti-scratch film, a light scattering film, and an anti-fog film; and / or The second optical film is any one of the following: polarizing film, quarter-wave plate, half-wave plate, anti-reflective film, scratch-resistant film, light scattering film, and anti-fog film.

11. The film attaching method according to any one of claims 1 to 8, wherein The first optical film has a multilayer structure.

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