Optical filter, camera module and terminal equipment

Abstract

The utility model discloses an optical filter, camera module and terminal equipment, the optical filter comprises a base material, a filter film layer, a spin coating film layer, an antireflection film layer and an inorganic matter layer, the base material has a first surface and a second surface which are arranged back to back, the filter film layer is arranged on the first surface, the spin coating film layer is arranged on the second surface, and the antireflection film layer is arranged on the second surface. The antireflection film layer is arranged on the side, away from the second surface, of the spin-coating film layer, the inorganic matter layer is arranged between the second surface and the spin-coating film layer, and the inorganic matter layer is configured to enable the spin-coating film layer to be connected to the second surface. According to the optical filter, the camera module and the terminal equipment provided by the utility model, the adhesive force between the spin-coating film layer and the base material can be improved, and the stability of the overall structure of the optical filter is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of optical elements, in particular to a filter, a camera module and a terminal device. Background Art

[0002] The filter is usually arranged on the light-sensitive surface side of the light-sensitive chip of the camera module to filter the light converged by the camera module. With the increasing requirements for the imaging quality of the camera module, as an important component that can improve the imaging quality of the camera module, higher requirements are also imposed on the filter.

[0003] In the related art, the filter usually includes a glass substrate, and a spin-coated film layer is formed on the surface of the glass substrate. However, the adhesion between the spin-coated film layer and the glass substrate is poor, and the spin-coated film layer is easy to fall off, thereby affecting the stability of the overall structure of the filter. Summary of the Utility Model

[0004] Embodiments of the utility model disclose a filter, a camera module and a terminal device, which can improve the adhesion between the spin-coated film layer and the substrate and enhance the stability of the overall structure of the filter.

[0005] To achieve the above object, in a first aspect, embodiments of the utility model disclose a filter, including:

[0006] A substrate having a first surface and a second surface disposed opposite to each other;

[0007] A filter film layer disposed on the first surface;

[0008] A spin-coated film layer disposed on the second surface;

[0009] An anti-reflection film layer disposed on a side of the spin-coated film layer away from the second surface; and,

[0010] An inorganic layer disposed between the second surface and the spin-coated film layer, and the inorganic layer is configured to connect the spin-coated film layer to the second surface.

[0011] By adding an inorganic layer between the substrate and the spin-coated film layer, the filter of the utility model uses the inorganic substance as the bonding layer between the spin-coated film layer and the substrate, can overcome the heterogeneity between the spin-coated film layer and the substrate, improve the adhesion between the spin-coated film layer and the substrate, avoid the peeling off of the spin-coated film layer, improve the stability of the overall structure of the filter, and further enhance the optical performance of the filter.

[0012] As an optional implementation manner, in the embodiment of the first aspect, the material of the inorganic layer includes a low refractive index material, and the refractive index range of the low refractive index material is 1.4 - 1.7.

[0013] By adopting an inorganic layer made of a low-refractive-index material, the transmittance and reflectivity of light can be improved, the light loss in optical devices can be effectively reduced, and the light utilization rate can be increased. Moreover, the inorganic layer formed by the low-refractive-index material can have good mechanical strength and stability, which is more conducive to the firmness between the spin-coated film layer and the substrate.

[0014] As an alternative embodiment, in the embodiment of the first aspect, the low-refractive-index material includes at least one of silicon dioxide, silicon oxide, and magnesium oxide.

[0015] By using materials such as silicon dioxide, silicon oxide, and magnesium oxide to form an inorganic layer, the adhesion between the substrate and the spin-coated film layer can be effectively improved, the spin-coated film layer can be prevented from falling off, and thus the stability of the filter can be improved.

[0016] As an alternative embodiment, in the embodiment of the first aspect, in the direction perpendicular to the substrate, the thickness of the inorganic layer is 5 nm - 20 nm.

[0017] As a bonding layer between the substrate and the spin-coated film layer, by controlling the thickness of the inorganic layer within a reasonable range, the bonding degree between the spin-coated film layer and the substrate can be improved, the spin-coated film layer can be more firmly attached to the substrate, and thus the firmness of the spin-coated film layer can be improved.

[0018] As an alternative embodiment, in the embodiment of the first aspect, the inorganic layer has a plurality of nano-scale columnar microstructures, and the plurality of columnar microstructures are connected to each other and are distributed in the direction perpendicular to the substrate, and the length of each columnar microstructure extends in the direction perpendicular to the substrate.

[0019] The microstructure of the inorganic layer is columnar, and the extending direction of the length of the columnar structure is consistent with the thickness direction of the entire filter. Such a continuously distributed structure can enable the inorganic layer to have a good bonding interface with the substrate and the spin-coated film layer, resulting in a better bonding effect, and thus improving the bonding strength between the spin-coated film layer and the substrate.

[0020] As an alternative embodiment, in the embodiment of the first aspect, the inorganic layer is formed on the second surface by an evaporation process.

[0021] Forming the inorganic layer by evaporation can make the inorganic layer more uniform, dense, and have strong adhesion. It should be noted that before forming the inorganic layer, the surface of the substrate needs to be pretreated to ensure the cleanliness of the substrate surface to obtain better adhesion. In addition, before starting the plating, it is necessary to be far away from the plasma source to avoid affecting the evaporation process.

[0022] As an alternative embodiment, in the embodiment of the first aspect, the substrate is white glass or blue glass.

[0023] By using a glass substrate, the filter can have excellent optical properties and stability.

[0024] As an alternative embodiment, in the embodiment of the first aspect, along the direction perpendicular to the substrate, the thickness of the substrate is 0.07 mm - 0.31 mm, and / or the thickness of the filter film layer is 2500 nm - 4500 nm, and / or the thickness of the anti-reflection film layer is 2000 nm - 6000 nm.

[0025] By reasonably controlling the thickness ranges of the substrate, the filter film layer, and the anti-reflection film layer, while enabling these film layers to have good optical effects, the thickness will not be too thick, which is beneficial to the thinning of the filter.

[0026] In a second aspect, the present utility model discloses a camera module, which includes a lens assembly, an image sensor, and a filter as described in the first aspect, and the filter is disposed between the lens assembly and the image sensor.

[0027] In a third aspect, the present utility model discloses a terminal device, which includes a housing and a camera module as described in the second aspect, and the camera module is disposed on the housing.

[0028] Compared with the prior art, the beneficial effects of the present utility model are:

[0029] The present utility model provides a filter, which includes a substrate, a filter film layer, a spin-coated film layer, an anti-reflection film layer, and an inorganic layer. The substrate has a first surface and a second surface disposed opposite to each other. The filter film layer is disposed on the first surface, the spin-coated film layer is disposed on the second surface, the anti-reflection film layer is disposed on the side of the spin-coated film layer away from the second surface, and the inorganic layer is disposed between the second surface and the spin-coated film layer. The inorganic layer is configured to connect the spin-coated film layer to the second surface. By adding an inorganic layer between the substrate and the spin-coated film layer, and using the inorganic substance as the bonding layer between the spin-coated film layer and the substrate, the heterogeneity between the spin-coated film layer and the substrate can be overcome, the adhesion between the spin-coated film layer and the substrate can be improved, the peeling off of the spin-coated film layer can be avoided, the stability of the overall structure of the filter can be improved, and thus the optical performance of the filter can be enhanced. Description of the Drawings

[0030] To more clearly illustrate the technical solutions in the embodiments of the present utility model, the accompanying drawings required for use in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present utility model. For those skilled in the art of traditional technology, other accompanying drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 Schematic three-dimensional structure diagram of the filter disclosed by the present utility model;

[0032] Figure 2 Schematic side view of the filter disclosed by the present utility model;

[0033] Figure 3 Schematic diagram of the optical performance curve of the filter disclosed by the present utility model;

[0034] Figure 4 Schematic diagram of the reflection performance curve of the filter disclosed by the present utility model;

[0035] Figure 5 Schematic three-dimensional structure diagram of the camera module disclosed by the present utility model;

[0036] Figure 6 Schematic three-dimensional structure diagram when the terminal device disclosed by the present utility model is a mobile phone.

[0037] Explanation of reference numerals:

[0038] 100, filter; 10, substrate; 20, filter film layer; 30, spin-coated film layer; 40, antireflection film layer; 50, inorganic layer; 200, camera module; 201, lens assembly; 202, image sensor; 300, terminal device; 301, housing. Specific embodiments

[0039] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art of traditional technology without creative efforts fall within the scope of protection of the present utility model.

[0040] In the present utility model, terms such as "upper" and "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly used to better describe the present utility model and its embodiments, and are not used to limit that the indicated device, element or component must have a specific orientation, or be constructed and operated in a specific orientation.

[0041] Moreover, in addition to being used to indicate orientation or positional relationship, some of the above terms may also be used to express other meanings. For example, the term "upper" may also be used to indicate a certain attachment relationship or connection relationship in some cases. For those skilled in the art of traditional technology, the specific meanings of these terms in the present utility model can be understood according to specific circumstances.

[0042] In addition, the terms "provided with" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, components or parts. For those skilled in the art of traditional technology, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0043] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, components or parts (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, components or parts. Unless otherwise specified, the meaning of "a plurality" is two or more.

[0044] The technical solution of the present utility model will be further described below in conjunction with embodiments and drawings.

[0045] Please refer to Figure 1 and Figure 2 together. An embodiment of the present utility model discloses a filter 100. Among them, the filter 100 includes a substrate 10, a filter film layer 20, a spin coating layer 30, an antireflection film layer 40, and an inorganic layer 50. The substrate 10 has a first surface 11 and a second surface 12 disposed opposite to each other. The filter film layer 20 is disposed on the first surface 11, the spin coating layer 30 is disposed on the second surface 12, the antireflection film layer 40 is disposed on a side of the spin coating layer 30 away from the second surface 12, and the inorganic layer 50 is disposed between the second surface 12 and the spin coating layer 30. The inorganic layer 50 is configured to connect the spin coating layer 30 to the second surface 12.

[0046] By adding the inorganic layer 50 between the substrate 10 and the spin coating layer 30, the filter 100 of the present utility model uses the inorganic substance as the bonding layer between the spin coating layer 30 and the substrate 10, which can overcome the heterogeneity between the spin coating layer 30 and the substrate 10, improve the adhesion between the spin coating layer 30 and the substrate 10, avoid the peeling off of the spin coating layer 30, improve the stability of the overall structure of the filter 100, and thus enhance the optical performance of the filter 100.

[0047] Optionally, the filter film layer 20 can be an infrared cut-off film, which can filter out light in other wavelength bands such as infrared light and only allow visible light to pass through, making the imaging more in line with the visual experience of the human eye. Of course, in other embodiments, the filter film can also be an ultraviolet cut-off film for filtering out ultraviolet light in the light, which can be selected according to actual needs and is not specifically limited in this embodiment.

[0048] Further, in the direction perpendicular to the substrate 10, the thickness of the filter film layer 20 can be 2500nm - 4500nm, such as 3000nm, 3500nm, 4000nm, etc. By reasonably controlling the thickness range of the filter film layer 20, while enabling the filter film layer 20 to have good optical effects, the thickness will not be too thick, which is beneficial to the thinning of the filter 100.

[0049] In addition, the filter film layer 20 can be formed by plating multiple layers of films to ensure a high transmittance in the visible light band. The number of film layers of the filter film layer 20 can be in the range of 30 - 50 layers, such as 34 layers, 36 layers or 40 layers, etc. The specific number of layers can be selected and designed according to actual needs as long as it can meet the requirement of having good optical effects. Further, the material of the filter film layer 20 can be one or more of titanium trioxide, silicon dioxide, titanium dioxide, magnesium oxide, etc.

[0050] Optionally, in the direction perpendicular to the substrate 10, the thickness of the anti-reflection film layer 40 can be 2000nm - 6000nm, such as 2500nm, 3000nm, 4000nm, etc. By reasonably controlling the thickness range of the anti-reflection film layer 40, while enabling the anti-reflection film layer 40 to have good optical effects, the thickness will not be too thick, which is beneficial to the thinning of the filter 100.

[0051] In addition, the anti-reflection film layer 40 can include multiple film layers. The number of film layers can be in the range of 4 - 50 layers, such as 45 layers, 47 layers or 49 layers, etc. The specific number of layers can be selected and designed according to actual needs as long as it can meet the requirement of having good transmission effect at a suitable thickness. Further, the material of the anti-reflection film layer 40 can be one or more of magnesium fluoride, titanium trioxide, titanium dioxide, magnesium oxide, etc.

[0052] In some possible implementation manners, the thickness of the substrate 10 is 0.07mm - 0.31mm, such as 0.11mm, 0.20mm or 0.25mm, etc. By controlling the thickness of the substrate 10 within a reasonable range, the substrate 10 can have sufficient strength while the thickness will not be too high, which is beneficial to the thinning of the filter 100 and thus beneficial to the overall thinning of the camera module 200.

[0053] Optionally, the material of the substrate 10 can be white glass or blue glass. By using a glass substrate, the filter 100 can have excellent optical properties and stability. Of course, in other embodiments, materials such as plastic or resin can also be used, and the specific material selection can be based on application requirements such as optical properties, mechanical strength, heat resistance, and cost.

[0054] It can be understood that taking the filter film layer 20 as an infrared cut-off film as an example, when the substrate 10 is blue glass, the filter 100 is an absorption type filter, and infrared light can be filtered by absorption. The blue glass can further absorb the reflected infrared light and will not show color deviation with the increase of the angle, and can greatly control optical phenomena such as glare and ghosting. When the substrate 10 is white glass, the filter 100 is a reflection type filter, and it plays a filtering role by reflecting infrared rays and some other rays.

[0055] In some possible embodiments, the material of the inorganic layer 50 can include a low refractive index material, and the refractive index of the low refractive index material ranges from 1.4 to 1.7. For example, it can be 1.56, 1.61, 1.67, etc. By using the inorganic layer 50 made of a low refractive index material, the transmittance and reflectivity of light can be improved, the light loss in the optical device can be effectively reduced, and the light utilization rate can be improved. Moreover, the inorganic layer 50 formed by the low refractive index material can have good mechanical strength and stability, which is more conducive to the firmness between the spin-coated film layer 30 and the substrate 10.

[0056] Optionally, the low refractive index material can include at least one of silicon dioxide, silicon oxide, and magnesium oxide. By using the materials of silicon dioxide, silicon oxide, and magnesium oxide to form the inorganic layer 50, the adhesion between the substrate 10 and the spin-coated film layer 30 can be effectively improved, the spin-coated film layer 30 can be prevented from falling off, and thus the stability of the filter 100 can be improved.

[0057] In some possible embodiments, along the direction perpendicular to the substrate 10, the thickness of the inorganic layer 50 is 5 nm - 20 nm. For example, it can be 8 nm, 12 nm, or 15 nm, etc. As a bonding layer between the substrate 10 and the spin-coated film layer 30, by controlling the thickness of the inorganic layer 50 within a reasonable range, the bonding degree between the spin-coated film layer 30 and the substrate 10 can be improved, and the spin-coated film layer 30 can be more firmly attached to the substrate 10, thereby improving the firmness of the spin-coated film layer 30.

[0058] Furthermore, the inorganic layer 50 may have a plurality of nanoscale columnar microstructures. The plurality of columnar microstructures are interconnected and distributed in a direction perpendicular to the substrate 10, and the length of each columnar microstructure extends in a direction perpendicular to the substrate 10. That is, the microstructure of the inorganic layer 50 is columnar, and the extending direction of the length of the columnar structure is consistent with the thickness direction of the entire filter 100. Such a continuously distributed structure can enable the inorganic layer 50 to have a good bonding interface with the substrate 10 and the spin-coated film layer 30, resulting in a better bonding effect, thereby improving the bonding strength between the spin-coated film layer 30 and the substrate 10.

[0059] It should be noted that the columnar microstructures of the inorganic layer of the present utility model can be the microscopic morphology of the surface of the inorganic layer, and this microstructure can be obtained by observing through microscopy techniques.

[0060] In some possible implementation manners, the inorganic layer 50 can be formed on the second surface 12 by an evaporation process. Forming the inorganic layer 50 by evaporation can make the inorganic layer 50 more uniform, dense, and have strong adhesion. It should be noted that before forming the inorganic layer 50, the surface of the substrate 10 needs to be pretreated to ensure the cleanliness of the surface of the substrate 10 to obtain better adhesion. In addition, before starting the plating, it is necessary to stay away from the plasma source to avoid affecting the evaporation process.

[0061] Of course, in other embodiments, the inorganic layer 50 can also be formed by processes such as sputtering, electroplating, or electroless plating. Similarly, the inorganic layer 50 can be formed on the second surface 12 of the substrate 10. The specific method can be selected according to actual needs as long as it can achieve good bonding between the spin-coated film layer 30 and the substrate 10.

[0062] In addition, it should also be noted that the spin-coated film layer 30 in this embodiment is an absorption layer formed by a spin-coating process, which can enable the substrate 10 to have the function of absorbing red light or near-infrared light. This technology is a publicly known technology in the art, and this embodiment will not elaborate on it in detail. Only a simple comparison of the optical properties of the filter 100 formed by this spin-coating process with those of the related art is made. It can be understood that the filter formed by the related technology can be a filter formed by a non-spin-coating process technology.

[0063] Please refer to Figure 3 , Figure 3It is an optical performance curve graph of the filter 100 formed by the spin coating process in the related art. In the graph, the horizontal axis represents the spectral wavelength, and the vertical axis represents the transmittance. Curve L1 is the transmittance curve of the blue glass filter in the related art at an incident angle of 0°, curve L2 is the transmittance curve of the blue glass filter in the related art at an incident angle of 30°, curve L3 is the transmittance curve of the blue glass filter formed by the spin coating process at an incident angle of 0°, and curve L4 is the transmittance curve of the blue glass filter formed by the spin coating process at an incident angle of 30°. It can be seen that there is a large drift in the transmittance curve of the blue glass filter 100 in the related art between 0° and 30°, and the transmittance curves of the blue glass filter 100 formed by the spin coating process between 0° and 30° can have good coincidence, which is beneficial to reducing petal-shaped stray light and reducing aberration.

[0064] Please refer to Figure 4 , Figure 4 It is a reflectance curve graph of the filter 100 formed by the spin coating process in the related art. In the graph, the horizontal axis represents the spectral wavelength, and the vertical axis represents the reflectance. Curve L5 is the reflectance curve of the blue glass filter 100 in the related art, and curve L6 is the reflectance curve of the blue glass filter 100 formed by the spin coating process. It can be seen that the reflectance of the blue glass filter 100 in the related art shows a rapid upward trend after 670 nm. The blue glass filter 100 formed by the spin coating process has a lower reflectance in a wider red light band, has a lower reflectance, higher imaging brightness, and can reduce halos and ghosts at the same time.

[0065] The present utility model also discloses an imaging module 200. Refer to Figure 5 , the imaging module 200 includes a lens assembly 201, an image sensor 202, and the filter 100 as described in the above embodiment. The filter 100 is disposed between the lens assembly 201 and the image sensor 202, and is used to filter out some of the light in the object-side light from the lens assembly 201, so that the other part of the light is provided to the image sensor 202 for effective and accurate imaging. Among them, the image sensor 202 can be a Complementary Metal Oxide Semiconductor (CMOS) or a Charge-coupled Device (CCD). The imaging module 200 can be an imaging module integrated on the terminal device 300 or an independent lens. It can be understood that the imaging module 200 having the above filter 100 has all the technical effects of the above filter 100. Since the above technical effects have been described in detail in the embodiment of the filter 100, they will not be repeated here.

[0066] Please refer to Figure 6, the present utility model also discloses a terminal device 300, which includes a housing 301 and the camera module 200 as described in the above embodiments, and the camera module 200 is disposed on the housing 301. Among them, the terminal device 300 may include, but is not limited to, mobile phones, tablet computers, laptop computers, smart watches, vehicle-mounted devices, drones, monitors, etc. Taking the terminal device 300 as a mobile phone as an example, at this time, the camera module 200 can be arranged on the housing 301.

[0067] It can be understood that the terminal device 300 having the above camera module 200 also has all the technical effects of the above filter 100. Since the above technical effects have been described in detail in the embodiments of the filter 100, they will not be repeated here.

[0068] The above has introduced in detail the filter, the camera module and the terminal device disclosed in the embodiments of the present utility model. Specific examples are used in this article to elaborate on the principle and implementation manner of the present utility model. The description of the above embodiments is only used to help understand the filter, the camera module and the terminal device of the present utility model and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present utility model, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present utility model.

Claims

1. A filter, characterized in that: include: A substrate having a first surface and a second surface disposed opposite to each other; A filter film layer, the filter film layer is disposed on the first surface; A spin-coated film layer, wherein the spin-coated film layer is disposed on the second surface; an anti-reflection film layer, the anti-reflection film layer being arranged on a side of the spin-coated film layer away from the second surface; as well as, The inorganic layer is disposed between the second surface and the spin-on film layer, and the inorganic layer is configured to connect the spin-on film layer to the second surface.

2. The optical filter according to claim 1, characterized in that: The material of the inorganic layer includes a low refractive index material, and the refractive index of the low refractive index material is in the range of 1.4-1.

7.

3. The optical filter according to claim 2, characterized in that: The low refractive index material is one of silicon dioxide, silicon oxide and magnesium oxide.

4. The optical filter according to claim 1, characterized in that Along the direction perpendicular to the substrate, the thickness of the inorganic layer is 5nm-20nm.

5. The optical filter according to claim 1, characterized in that: The inorganic layer has a plurality of nanometer-scale columnar microstructures, the plurality of columnar microstructures are interconnected and distributed along a direction perpendicular to the substrate, and the length of each columnar microstructure extends along a direction perpendicular to the substrate.

6. The optical filter according to claim 1, characterized in that: The inorganic layer is formed on the second surface by an evaporation process.

7. The optical filter according to any one of claims 1 to 6, characterized in that: The substrate is white glass or blue glass.

8. The optical filter according to claim 7, characterized in that: Along the direction perpendicular to the substrate, the thickness of the substrate is 0.07mm-0.31mm, and / or the thickness of the filter film layer is 2500nm-4500nm, and / or the thickness of the anti-reflection film layer is 2000nm-6000nm.

9. A camera module, characterized in that: The camera module includes a lens assembly, an image sensor, and a filter as described in any one of claims 1 to 8, wherein the filter is arranged between the lens assembly and the image sensor.

10. A terminal device, characterized in that: The terminal device includes a shell and a camera module as described in claim 9, and the camera module is arranged on the shell.

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