A manufacturing method of a lens module

Abstract

The present invention provides a lens module and a manufacturing method thereof. The lens module comprises: a lens assembly comprising, from top to bottom, a first glass lens, a first resin lens, a second glass lens, and a second resin lens pressed together; and an image sensor bonded to the second resin lens. The lens module is a hybrid structure of glass and resin, with the glass and resin lenses alternately stacked to form a stacked structure. No air layer exists between the glass and resin lenses, resulting in a more compact lens module. There is also no air layer within the resin lenses, thereby meeting higher optical requirements and reducing module size. The lens module is lightweight and thin, offering improved optical performance and higher ambient temperature adaptability, allowing for a wider range of applications.

Description

Technical Field

[0001] The present invention belongs to the field of camera module manufacturing, and in particular relates to a lens module and a manufacturing method thereof. Background Art

[0002] The main components of a lens module include a lens and an image sensor. Its primary operating principle is: the optical image of the scene is projected onto the surface of the image sensor, which then converts it into an electrical signal. The lens, composed of a combination of different lenses, is a crucial component of the lens module and plays a crucial role in imaging quality. The lens primarily determines image clarity, image display range, and maximum pixel count. The image sensor, the core module of the lens module, converts light into electrical signals.

[0003] Wafer-level optics (WLO) refers to optical components manufactured using wafer-level lens manufacturing technology and processes. Unlike traditional optical component processing techniques, the WLO process uses semiconductor technology to batch-replicate lens modules on a single wafer. Multiple lens wafers are then laminated together and cut into individual lens modules. As product imaging requirements continue to increase, higher demands are being placed on lens design height, optical performance, and stability. Conventional lens module performance breakthroughs have reached a bottleneck. Summary of the Invention

[0004] The object of the present invention is to provide a lens module and a manufacturing method thereof, so as to obtain a more compact lens module without an air layer inside the resin lens, thereby meeting higher optical requirements and reducing the module size.

[0005] The present invention provides a method for manufacturing a lens module, comprising:

[0006] forming a first glass layer comprising a plurality of first glass lenses, each of which comprises a curved surface area and a flat surface area surrounding the curved surface area;

[0007] Providing a second glass layer, and forming a first resin layer located between the first glass layer and the second glass layer by lamination, wherein the first resin layer includes a plurality of first resin lenses; and the second glass layer includes a plurality of second glass lenses;

[0008] forming a second resin layer on a surface of the second glass layer away from the first resin layer, wherein the second resin layer includes a plurality of second resin lenses;

[0009] Cutting a lens stack layer composed of the first glass layer, the first resin layer, the second glass layer, and the second resin layer to form a lens assembly at a grain level; the lens assembly includes, from top to bottom, the first glass lens, the first resin lens, the second glass lens, and the second resin lens that are pressed together;

[0010] An image sensor is provided, and the image sensor is bonded to the second resin lens.

[0011] Furthermore, the first glass layer is formed by a compression molding process, specifically comprising:

[0012] Providing a first mold, wherein the upper surface of the first mold is a plane; providing a second mold, wherein the lower surface of the second mold is formed with a plurality of equally spaced protrusions or depressions;

[0013] The first glass layer is formed between the first mold and the second mold by pressing and then heated and cured.

[0014] Furthermore, the first mold and the second mold are made of metal.

[0015] Furthermore, the first glass layer is wafer-level glass.

[0016] Furthermore, the number, size and position of the curved surface areas of the first resin layer correspond to the number, size and position of the curved surface areas of the second resin layer, respectively.

[0017] The present invention also provides a lens module, comprising:

[0018] A lens assembly, the lens assembly comprising, from top to bottom, a first glass lens, a first resin lens, a second glass lens, and a second resin lens pressed together;

[0019] An image sensor is bonded to the second resin lens.

[0020] Furthermore, the first glass lens includes a recessed area and a flat area surrounding the recessed area; the first resin lens includes a raised area and a flat area surrounding the raised area; the recessed area matches the raised area and is embossed together; the second resin lens includes a curved area and a flat area surrounding the curved area, and the curved area corresponds to the raised area in the thickness direction.

[0021] Furthermore, the second resin lens further includes a support portion extending from a planar area surrounding the curved area along the thickness direction, and the support portion is bonded to the image sensor; an air layer is formed between the second resin lens and the image sensor.

[0022] Furthermore, the surface of the second glass lens on the side close to the first resin lens is a plane or includes a curved portion and a plane portion surrounding the curved portion.

[0023] Furthermore, the lens module also includes a light-shielding layer, which covers the side walls and top of the lens module. The light-shielding layer has an opening in the middle area of the top of the lens module, and the opening corresponds to the position of the recessed area of the first glass lens in the thickness direction.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention provides a lens module and a manufacturing method thereof. The lens module comprises: a lens assembly comprising, from top to bottom, a first glass lens, a first resin lens, a second glass lens, and a second resin lens pressed together; and an image sensor bonded to the second resin lens. The lens module is a hybrid structure of glass and resin, with the glass and resin lenses alternately stacked to form a stacked structure. No air layer exists between the glass and resin lenses, resulting in a more compact lens module. There is also no air layer within the resin lenses, thereby meeting higher optical requirements and reducing module size. The lens module is lightweight and thin, offering improved optical performance and higher ambient temperature adaptability, allowing for a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 2 is a flow chart of a method for manufacturing a lens module according to an embodiment of the present invention.

[0027] Figures 2 to 5 Schematic diagram of each step of a method for manufacturing a lens module according to an embodiment of the present invention.

[0028] Figure 6 2 is a schematic diagram of an exemplary structure of a lens module according to an embodiment of the present invention.

[0029] Figure 7 FIG. 2 is another structural diagram of an exemplary lens module according to an embodiment of the present invention.

[0030] The accompanying drawings are numerals as follows:

[0031] 11-first mold; 12-first glass layer; 13-second mold; 14-first resin layer; 15-second glass layer; 16-second resin layer; 17-third mold; 18-adhesive layer; 19-light-shielding layer; 20-image sensor; 21-solder ball; 120-first glass lens; 140-first resin lens; 150-second glass lens; 150'-second glass lens; 160-second resin lens; 161-curved area; 162-flat area; 163-support part; K-opening. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are not to exact scale, and are only used for the purpose of conveniently and clearly illustrating the embodiments of the present invention.

[0033] For ease of description, some embodiments of the present application may use spatially relative terms such as "above," "below," "top," "below," etc. to describe the relationship between one element or component and another (or other) elements or components as shown in the various figures of the embodiments. It should be understood that, in addition to the orientations described in the figures, the spatially relative terms are also intended to include different orientations of the device in use or operation. For example, if the device in the figures is turned over, the elements or components described as being "below" or "beneath" other elements or components will subsequently be positioned as being "above" or "above" other elements or components. The terms "first," "second," etc., hereinafter, are used to distinguish between similar elements and are not necessarily used to describe a specific order or chronological sequence. It is to be understood that, where appropriate, these terms used in this manner are interchangeable.

[0034] The embodiment of the present invention provides a method for manufacturing a lens module, such as Figure 1 As shown, including:

[0035] Step S1, forming a first glass layer, which includes a plurality of first glass lenses, each of which includes a curved surface area and a flat surface area surrounding the curved surface area;

[0036] Step S2: providing a second glass layer, and forming a first resin layer between the first glass layer and the second glass layer by lamination, wherein the first resin layer includes a plurality of first resin lenses; and the second glass layer includes a plurality of second glass lenses;

[0037] Step S3, forming a second resin layer on a surface of the second glass layer away from the first resin layer, wherein the second resin layer includes a plurality of second resin lenses;

[0038] Step S4: cutting the lens stack layer composed of the first glass layer, the first resin layer, the second glass layer, and the second resin layer to form a lens assembly at a grain level; the lens assembly includes, from top to bottom, the first glass lens, the first resin lens, the second glass lens, and the second resin lens that are pressed together;

[0039] Step S5: providing an image sensor, and bonding the image sensor to the second resin lens.

[0040] The following combination Figures 2 to 7 The steps of the method for manufacturing the lens module according to the embodiment of the present invention are described in detail.

[0041] See also Figure 2 A first mold 11 is provided, the upper surface of which is flat. Next, a first glass layer 12 is formed on the upper surface of the first mold 11, covering the surface of the first mold 11. In this embodiment, the first glass layer 12 can be applied to the surface of the first mold 11 using a coating process. At this point, the first glass layer 12 is in a fluid, gel-like state. A second mold 13 is provided, the lower surface of which is formed with a plurality of equally spaced protrusions or depressions. The size of the protrusions or depressions is related to the size of the first glass lens to be formed.

[0042] Then, if Figure 2 and Figure 6 As shown, the second mold 13 is aligned and pressed against the first mold 11 to press the first glass layer 12 into a fixed shape. The first mold 11 and the second mold 13 are made of metal. The first glass layer 12 is then heated to solidify. The solidified first glass layer 12 includes a plurality of first glass lenses 120, which are now completely connected. The first glass layer 12 is formed into a first glass wafer (glass wafer-level lens) through a hot pressing molding process. Each first glass lens 120 includes a curved surface area and a flat surface area surrounding the curved surface area. The curved surface area is formed by pressing the protrusions on the surface of the second mold 13 together, while the flat surface area is formed by pressing the surfaces of the second mold 13 and the first mold 11 together. Typically, the center area of the curved surface area serves as the light-transmitting area, while the edge areas of the curved surface area have poor imaging quality due to astigmatism or distortion. The flat surface area serves as the fixed area. After the first glass layer 12 is solidified, the first mold 11 and the second mold 13 are demolded from the first glass layer 12.

[0043] Then, if Figure 3 and Figure 6 As shown, a first resin layer 14 is formed on the surface of the first glass layer 12. The first resin layer 14 fills the depressions on the surface of the first glass layer 12 and extends to cover the upper surface of the first glass layer 12. In this embodiment, the first resin layer 14 is, for example, a polymer and is applied to the surface of the first glass layer 12 using a coating process. At this point, the first resin layer 14 is in a fluid, gel-like state. A second glass layer 15 is provided, and both the upper and lower surfaces of the second glass layer 15 are planar.

[0044] Next, the second glass layer 15 is aligned and pressed against the first glass layer 12, and the first resin layer 14 is pressed into a fixed shape. The first resin layer 14 is then cured using ultraviolet radiation, forming a first resin wafer. The cured first resin layer 14 (first resin wafer) comprises a plurality of first resin lenses 140, which are now completely connected. Each first resin lens 140 includes a curved surface area and a flat surface area surrounding the curved surface area. The curved surface area is formed by pressing together the concave surface of the first glass layer 12.

[0045] like Figure 4 and Figure 6 As shown, a third mold 17 is provided. The surface of the third mold 17 is formed with a number of equally spaced depressions, with grooves disposed between adjacent depressions. The cross-sectional shape of the grooves is, for example, an inverted trapezoid. The dimensions of the depressions and grooves are related to the dimensions of the second resin lens 160 to be formed. A second resin layer 16 is formed on the surface of the third mold 17. The second resin layer 16 fills the depressions and grooves on the surface of the third mold 17 and extends to cover the upper surface of the third mold 17.

[0046] The side surface of the second glass layer 15 away from the first resin layer 14 is aligned and pressed with the third mold 17 to press the second resin layer 16 into a fixed shape to form a second resin wafer.

[0047] like Figure 5 and Figure 6 As shown, the third mold 17 is demoulded and removed to form a lens stack layer which is sequentially stacked by the second resin layer 16, the second glass layer 15, the first resin layer 14 and the first glass layer 12. The wafer-level lens stack layer is cut to form a grain-level lens assembly, as shown in FIG. Figure 6 As shown, the lens assembly includes, from bottom to top, a second resin lens 160, a second glass lens 150, a first resin lens 140, and a first glass lens 120. In this embodiment, the number, size, and position of the curved surface areas of the first resin layer 14 correspond to the number, size, and position of the curved surface areas of the second resin layer 16.

[0048] The first glass layer 12 is a WLG wafer-level glass lens. The glass has better light transmittance and a higher refractive index, which can obtain a larger amount of light. The second glass layer 15 is a conventional glass substrate or a WLG wafer-level glass lens. The glass has low dispersion and multi-layer coating to improve image quality. The integration of WLG wafer-level glass lenses and resin lenses has a high degree of freedom in lens design, a smaller module volume, better optical performance, lower thermal expansion and contraction effects, and higher adaptability to ambient temperature. The lens assembly can be designed as a square and modular design, and can be expanded to a 2x2 lens module in the future. The WLO process is more suitable for mobile consumer electronic devices, especially when the structure of the 3D vision transmitter is complex. Wafer-level optical elements can effectively reduce the volume space. At the same time, the device has good consistency, light weight, low height, and high beam quality. The use of semiconductor technology has cost advantages after large-scale mass production.

[0049] like Figure 6 As shown, the lens assembly and image sensor 20 are assembled. Specifically, glue or an adhesive layer 18 can be applied to the image sensor 20. Next, the lens assembly and image sensor 20 are aligned and bonded to each other via the adhesive layer 18 to form a lens module. Solder balls 21 are formed on the side of the image sensor 20 facing away from the second resin lens 160. An air layer is formed between the second resin lens 160 and the image sensor 20.

[0050] The second glass lens 150 is made by a hot pressing molding process, and its design shape is adjusted according to optical imaging simulation. It can be a flat lens structure or a lens structure with a certain curvature. Figure 6 The figure shows a case where the surface of the second glass lens 150 close to the first resin lens 140 is a flat surface. Figure 7 The second glass lens 150' is shown to have a curved surface and a flat surface surrounding the curved surface on the side close to the first resin lens 140. That is, the second glass lens 150' is a curved lens structure with a certain curvature, and the curved surface corresponds to the position of the concave area of the first glass lens 120 in the thickness direction. For example, the curved surface includes a plurality of protrusions or depressions. Figure 7 The curved portion includes two protrusions, and the projection of the concave area of the first glass lens 120 onto the second glass lens 150 ′ covers the two protrusions of the curved portion.

[0051] Next, a light-shielding layer 19 is formed on the side walls and top of the lens module. The light-shielding layer 19 is located in the middle area of the top of the lens module and has an opening K for light to enter. The light-shielding layer 19 is, for example, a black photoresist, which is a material with a photosensitivity effect and can be opaque after curing. The black photoresist is exposed to form the opening K. Since the light-shielding layer 19 is formed by an exposure process in this embodiment, the process is simple and easy to control, and the shape and size of the light-shielding layer 19 can be very precise. Of course, the material of the light-shielding layer 19 is not limited to black photoresist, but can also be plastic or metal materials, so as to have stronger wear resistance and stability; the light-shielding layer 19 can also be black paint, which can be formed by spraying and baking processes. The process of forming the light-shielding layer 19 is not limited to the exposure process, but can also be a coating or sputtering process.

[0052] Optionally, before forming the first glass layer 12 on the surface of the first mold 11 or before aligning and pressing the second mold 13 with the first mold 11, a release adhesive may be applied to the surfaces of the second mold 13 and the first mold 11 to facilitate demoulding. Figure 2 The first mold 11 and the second mold 13 are only schematically shown, but should not be limited thereto. The shapes and sizes of the first mold 11 and the second mold 13 can be designed according to the shape and size of the lens to be formed. Figure 4 The shape and size of the third mold 17 can be designed according to the shape and size of the lens to be formed.

[0053] Based on this, Figure 6 As shown, this embodiment also provides a lens module, including:

[0054] The lens assembly includes, from top to bottom, a first glass lens 120, a first resin lens 140, a second glass lens 150, and a second resin lens 160 that are pressed together;

[0055] The image sensor 20 is bonded to the second resin lens 160 .

[0056] Specifically, the optical areas of each lens of the lens assembly are projected onto the image sensor 20 in an overlapping or close manner. The light-sensitive surface of the image sensor 20 faces the lens assembly. The lens assembly is mounted on the light-sensitive surface of the image sensor 20. The image sensor 20 is bonded to the second resin lens 160.

[0057] The first glass lens 120 includes a recessed area and a planar area surrounding the recessed area; the first resin lens 140 includes a raised area and a planar area surrounding the raised area; the recessed area matches the raised area and is embossed together; the second resin lens 160 includes a curved area and a planar area surrounding the curved area, and the curved area of the second resin lens 160 corresponds to the position of the raised area of the first resin lens 140 in the thickness direction.

[0058] The second resin lens 160 further includes a support portion 163 extending from the flat area 162 surrounding the curved area 161 in the thickness direction. The support portion 163 is bonded to the image sensor 20 . An air layer is formed between the second resin lens 160 and the image sensor 20 .

[0059] The lens module also includes a shading layer 19, which covers the side walls and top of the lens module. The shading layer 19 has an opening K in the middle area of the top of the lens module, and the opening K corresponds to the position of the recessed area of the first glass lens 120 in the thickness direction.

[0060] The first glass lens 120 and the first resin lens 140 both include a curved area and a flat area surrounding the curved area. The curved areas of the first glass lens 120 and the first resin lens 140 correspond to each other in thickness direction, and the flat areas also correspond to each other in thickness direction.

[0061] As an optional embodiment, the lens assembly in the present invention is not limited to including 4 lenses, but may also include 3, 5, 6 or even more lenses, depending on actual needs.

[0062] In summary, the present invention provides a lens module and a method for manufacturing the same. The lens module comprises: a lens assembly, which comprises, from top to bottom, a first glass lens, a first resin lens, a second glass lens, and a second resin lens pressed together; and an image sensor, which is bonded to the second resin lens. The lens module is a hybrid structure of glass and resin, with the glass and resin lenses arranged in an alternating and stacked configuration to form a more compact lens module. There is no air layer between the glass and resin lenses, resulting in a more compact lens module. There is also no air layer within the resin lens, thereby meeting higher optical requirements and reducing module size. The lens module is lightweight and thin, offering better optical performance and higher ambient temperature adaptability, allowing for a wider range of applications.

[0063] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. The methods disclosed in the embodiments are described briefly because they correspond to the devices disclosed in the embodiments. For relevant details, refer to the method description.

[0064] The above description is only a description of the preferred embodiment of the present invention, and does not limit the scope of the rights of the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for manufacturing a lens module, characterized in that: include: forming a first glass layer comprising a plurality of first glass lenses, each of which comprises a curved surface area and a flat surface area surrounding the curved surface area; Providing a second glass layer, and forming a first resin layer located between the first glass layer and the second glass layer by lamination, wherein the first resin layer includes a plurality of first resin lenses; and the second glass layer includes a plurality of second glass lenses; forming a second resin layer on a surface of the second glass layer away from the first resin layer, wherein the second resin layer includes a plurality of second resin lenses; Cutting a lens stack layer composed of the first glass layer, the first resin layer, the second glass layer, and the second resin layer to form a lens assembly at a grain level; the lens assembly includes, from top to bottom, the first glass lens, the first resin lens, the second glass lens, and the second resin lens that are pressed together; An image sensor is provided, and the image sensor is bonded to the second resin lens.

2. The method for manufacturing a lens module according to claim 1, wherein: The first glass layer is formed by a compression molding process, specifically comprising: Providing a first mold, wherein the upper surface of the first mold is a plane; providing a second mold, wherein the lower surface of the second mold is formed with a plurality of equally spaced protrusions or depressions; The first glass layer is formed between the first mold and the second mold by pressing and then heated and cured.

3. The method for manufacturing a lens module according to claim 2, wherein: The first mold and the second mold are made of metal.

4. The method for manufacturing a lens module according to claim 1, wherein: The first glass layer is wafer-level glass.

5. The method for manufacturing a lens module according to claim 1, wherein: The number, size, and position of the curved surface areas of the first resin layer correspond to the number, size, and position of the curved surface areas of the second resin layer, respectively.

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