Camera module and electronic device

Abstract

The embodiment of the present disclosure belongs to the technical field of optical imaging, and particularly relates to a camera module and an electronic device, which are used to improve the problem that the resolution of the camera module is difficult to be further improved. The camera module comprises a body and a cover, the body and the cover cooperate to form a sealed cavity; an image sensor and a microlens array are arranged in the sealed cavity; and an optical matching medium is filled in the sealed cavity; wherein the cover comprises an objective lens, the center line of the image sensor coincides with the optical axis of the objective lens, the microlens array is located between the image sensor and the objective lens, the optical matching medium is arranged between the objective lens and the microlens array, and the refractive index of the optical matching medium is greater than the refractive index of air. Compared with the fact that the medium between the objective lens and the image sensor in a common camera module is air, the embodiment of the present disclosure is beneficial to improving the resolution of the camera module by arranging the optical matching medium with high refractive index between the objective lens and the microlens array.

Description

Technical Field

[0001] This disclosure relates to the field of optical imaging technology, and more particularly to a camera module and electronic device. Background Technology

[0002] A camera module typically includes an objective lens, an image sensor, and a printed circuit board electrically connected to the image sensor. The objective lens and image sensor are positioned relative to each other. Incident light is projected onto the image sensor through the objective lens, and the light signal is processed into an electrical signal by the image sensor and transmitted to the printed circuit board. However, current camera modules still suffer from the problem of difficulty in further improving resolution. Summary of the Invention

[0003] This disclosure provides a camera module and electronic device to improve the problem that the resolution of camera modules is difficult to further improve in related technologies.

[0004] In a first aspect, embodiments of this disclosure provide a camera module, including:

[0005] The body and the cover are fitted together to form a sealed cavity;

[0006] An image sensor and a microlens array are disposed within the sealed cavity;

[0007] An optical matching medium is filled into the sealed cavity;

[0008] The cover includes an objective lens, the centerline of the image sensor coincides with the optical axis of the objective lens, the microlens array is located between the image sensor and the objective lens, and the optical matching medium is located between the objective lens and the microlens array. The refractive index of the optical matching medium is greater than that of air.

[0009] In one possible implementation, the optical matching medium includes a first medium and a second medium, the first medium and the second medium being distributed along the direction from the objective lens to the microlens array, the first medium being located on the side of the second medium closer to the objective lens, and the first medium and the second medium having different refractive indices.

[0010] In one possible implementation, both the first medium and the second medium are solids.

[0011] In one possible implementation, one of the first medium and the second medium is a solid, and the other of the first medium and the second medium is a liquid.

[0012] In one possible implementation, the optical matching medium further includes a third medium located between the first medium and the second medium, wherein the first medium and the second medium are both liquids and the third medium is a solid.

[0013] In one possible implementation, the refractive index of the optical matching medium gradually increases in a direction parallel to the optical axis of the objective lens and pointing from the objective lens toward the microlens array.

[0014] In one possible implementation, the refractive indices of the first medium, the second medium, and the third medium gradually increase in a direction parallel to the optical axis of the objective lens and pointing from the objective lens toward the microlens array.

[0015] In one possible implementation, when the optical matching medium comprises a liquid, the body is provided with a first opening and a second opening, the first opening being configured to allow the liquid in the optical matching medium to enter or exit the sealed cavity, and the second opening being configured to cooperate with the first opening to allow the liquid in the optical matching medium to enter or exit the sealed cavity.

[0016] In one possible implementation, when the optical matching medium comprises a liquid, the body is provided with a first opening and the cover is provided with a second opening, the first opening being configured to allow the liquid in the optical matching medium to enter or exit the sealed cavity, and the second opening being configured to cooperate with the first opening to allow the liquid in the optical matching medium to enter or exit the sealed cavity.

[0017] In one possible implementation, the end of the optical matching medium near the objective lens is in contact with the objective lens, and the end of the optical matching medium near the microlens array is in contact with the microlens array.

[0018] In one possible implementation, the refractive index of the microlens array is greater than or equal to the refractive index of the optical matching medium.

[0019] In one possible implementation, when the optical matching medium comprises a liquid, the liquid includes one or more of water, glycerin, cedar oil, benzene, and carbon tetrachloride.

[0020] In one possible implementation, the image sensor includes a charge-coupled device or a complementary metal-oxide-semiconductor device.

[0021] In one possible implementation, a lens assembly is also included, located on the side of the objective lens away from the sealed cavity, and the lens assembly is detachably connected to the body or the cover. The objective lens includes multiple lenses arranged sequentially along the optical axis.

[0022] In one possible implementation, the microlens array includes multiple microlenses arranged in an array, and the image sensor includes multiple photosensitive units arranged in an array, with each microlens corresponding to one of the photosensitive units.

[0023] Secondly, embodiments of this disclosure also provide an electronic device, including the camera module described in the above embodiments, the camera module being configured to acquire optical images; the electronic device further includes a display module electrically connected to the camera module, the display module being configured to display the optical images.

[0024] This disclosure provides a camera module and electronic device, including a body and a cover, which cooperate to form a sealed cavity; an image sensor and a microlens array are disposed within the sealed cavity; and an optical matching medium is filled within the sealed cavity. The cover includes an objective lens, the centerline of the image sensor coincides with the optical axis of the objective lens, the microlens array is located between the image sensor and the objective lens, and an optical matching medium with a refractive index greater than that of air is provided between the objective lens and the microlens array. Compared to conventional camera modules where the medium between the objective lens and the image sensor is air, this disclosure, by providing a high-refractive-index optical matching medium between the objective lens and the microlens array, helps to reduce the size of the image projected onto the image sensor. This allows for the placement of smaller, more precisely-pitched photosensitive units on the image sensor, thereby improving the resolution of the camera module. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A schematic diagram of the structure of a camera module provided in this embodiment of the present disclosure. Figure 1 ;

[0027] Figure 2 A schematic diagram of the structure of a camera module provided in this embodiment of the present disclosure. Figure 2 ;

[0028] Figure 3A schematic diagram of a microlens array provided in this embodiment of the present disclosure. Figure 1 ;

[0029] Figure 4 A schematic diagram of a microlens array provided in this embodiment of the present disclosure. Figure 2 ;

[0030] Figure 5 A schematic diagram of the structure of a camera module provided in this embodiment of the present disclosure. Figure 3 ;

[0031] Figure 6 A schematic diagram of the structure of a camera module provided in this embodiment of the present disclosure. Figure 4 ;

[0032] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present disclosure. Detailed Implementation

[0033] A camera module typically includes an objective lens, an image sensor, and a printed circuit board electrically connected to the image sensor. The objective lens and image sensor are positioned relative to each other. Incident light is projected onto the image sensor through the objective lens, and the light signal is processed into an electrical signal by the image sensor and transmitted to the printed circuit board. It's worth noting that when light propagates in a medium with a low refractive index, because the refractive index is inversely proportional to the wavelength, the wavelength of light in the medium is longer, resulting in a larger diameter of the corresponding image and thus lower resolution between adjacent images. In typical camera modules, the medium between the objective lens and the image sensor is air. Air has a low refractive index, leading to low resolution in the camera module. For example, in typical camera modules, the resolution is generally only around 0.5 micrometers (µm); in this case, even using an image sensor with a higher resolution cannot improve the overall resolution of the camera module.

[0034] In view of this, embodiments of the present disclosure provide a camera module and electronic device, including: an objective lens and a microlens array, wherein an optical matching medium is provided between the objective lens and the microlens array, and the refractive index of the optical matching medium is greater than that of air. Compared to the conventional camera module where the medium between the objective lens and the image sensor is air, the present disclosure, by providing a high-refractive-index optical matching medium between the objective lens and the microlens array, facilitates shortening the wavelength of light in the medium, thereby reducing the diameter of the corresponding image. This allows for the placement of smaller, more precisely-pitched photosensitive units on the image sensor, ultimately improving the resolution of the camera module.

[0035] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions in the embodiments of this disclosure will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this disclosure. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this disclosure, and should not be construed as limiting this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure. The embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0036] It is worth noting that the camera module in this embodiment can be applied to the camera systems of electronic devices such as personal computers, portable display devices, and smartphones.

[0037] Reference Figure 1 and Figure 2 The camera module includes a body 10 and a cover 20, which cooperate to form a sealed cavity 301. An image sensor 11 and a microlens array 12 are disposed within the sealed cavity 301, which is also filled with an optical matching medium 30. For example, the body 10 may be a barrel-shaped structure, including a bottom wall and side walls connected to the bottom wall. The side walls surround the bottom wall, and one end of the side wall opposite to the bottom wall forms an opening. The cover 20 is used to seal this opening and is sealed to the body 10, thus forming the sealed cavity 301. In some embodiments, a sealant or sealing ring may be provided between the cover 20 and the body 10 to prevent the optical matching medium 30 from leaking from the sealed cavity 301. The image sensor 11 and the microlens array 12 are disposed within the sealed cavity 301, preventing them from contacting the external environment, which is beneficial for improving image quality and extending the lifespan of the camera module.

[0038] The cover 20 includes an objective lens 202 for optical imaging. The surface of the objective lens 202 closest to the image sensor 11 contacts the optical matching medium 30, while the surface furthest from the image sensor 11 does not contact the optical matching medium 30. In this embodiment, the centerline of the image sensor 11 coincides with the optical axis of the objective lens 202, so that the image sensor 11 and the objective lens 202 are positioned relative to each other. Specifically, the distance between the image sensor 11 and the image can be set so that the focal point of the objective lens 202 is aligned with the image sensor 11, allowing the objective lens 202 to image an optical image onto the image sensor 11.

[0039] For example, the cover 20 may also include a cover plate 201, through which the objective lens 202 can be connected to the body 10. For example, the objective lens 202 can be engaged with the cover plate 201, but is not limited thereto. The cover plate 201 can block the opening of the body 10 and form a sealed connection with the body 10, and the objective lens 202 is sealed to the cover plate 201, so that the cover plate 201, the objective lens 202 and the body 10 together form a sealed cavity 301.

[0040] In this embodiment, the image sensor 11 includes a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) device. The image sensor 11 converts the light signal imaged by the objective lens 202 into an electrical signal. A CCD image sensor, also known as a charge-coupled device image sensor, is a semiconductor device capable of converting optical images into digital signals. CCD image sensors are characterized by high image quality and high image resolution, and also have low power consumption and are easy to integrate. A CMOS image sensor, also known as a complementary metal-oxide-semiconductor (CMOS) image sensor, is a voltage-controlled amplification device. CMOS image sensors are characterized by fast processing speed and low cost. In this embodiment, the appropriate image sensor 11 can be selected according to different actual usage requirements. The microlens array 12 may include multiple microlenses arranged in an array. Of course, in some other embodiments, the image sensor 11 may also be one or more of the following image sensors: a photodiode array, a focal plane array, a multispectral sensor, etc.

[0041] For example, a printed circuit board (PCB) may also be disposed within the sealed cavity 301. The PCB is located on the side of the image sensor 11 facing away from the objective lens 202. The image sensor 11 is electrically connected to the PCB. For example, the image sensor 11 can be connected to the PCB via a ball grid array, so that the electrical signal generated by the incident light in the image sensor 11 is transmitted to the PCB, and the PCB outputs a digital image signal. Specifically, the PCB may be connected to the bottom wall of the body 10 so that the PCB is mounted on the body 10.

[0042] In this embodiment, the microlens array 12 is located between the image sensor 11 and the objective lens 202. The microlens array 12 is an array composed of lenses with apertures and relief depths in the micrometer range. The microlens array 12 may include multiple microlenses arranged in an array. The microlenses in the microlens array 12 may all be convex lenses to converge incident light.

[0043] It is worth noting that CMOS image sensors have pixel arrays, which are key functional modules directly related to image reproduction capabilities. Pixel arrays include front-side illuminated (FSI) pixel arrays and back-side illuminated (BSI) pixel arrays. This embodiment can select either a front-side illuminated or back-side illuminated pixel array according to actual needs, and no specific limitation is made here.

[0044] In the structure of a front-illuminated pixel array, a color filter layer (i.e., a color filter array), a metal layer, and a photosensitive layer can be stacked sequentially. A microlens array 12 covers the side of the color filter layer facing away from the metal layer. The color filter layer may include, for example, color filters arranged in repeating RGBW units. These color filters filter incident light to obtain light of the corresponding color; R may represent a red filter, G a green filter, B a blue filter, and W a white filter. The metal layer includes a circuit structure formed by multiple layers of metal wiring, used to transmit the photoelectric converted electrical signals to peripheral circuits for processing. CMOS technology utilizes control circuits and signal processing circuits as peripheral circuits. The substrate of the metal layer is silicon oxide, in which multiple layers of metal wiring are placed and electrically connected to form a circuit structure for transmitting electrical signals. The gaps between adjacent metal wirings form the light channels of the metal layer. The photosensitive layer contains multiple photosensitive units, and each color filter layer has a corresponding photosensitive unit. The orthographic projection of a color filter in a color filter layer onto the photosensitive layer covers its corresponding photosensitive unit. The matrix material of the photosensitive layer can be silicon, and the photosensitive unit can be, for example, a photosensitive diode (PD). The PD is used to perform photoelectric conversion on the received incident light. Since metal wiring is placed in the metal layer between the color filter layer and the PD, a certain spacing must be maintained between adjacent PDs. The optical channel of the photosensitive layer is connected to and aligned with the optical channel of the metal layer. The PD is located within the optical channel of the photosensitive layer, allowing incident light to pass through the color filter layer sequentially into the optical channel of the metal layer, then the optical channel of the photosensitive layer, and finally to the PD. The PD encounters photons and undergoes a photoelectric effect to achieve photoelectric conversion, then outputs a digital image signal through the circuit structure of the metal layer.

[0045] In the back-illuminated pixel array structure, the positions of the metal layer and the photosensitive layer in the above structure are interchanged; that is, a color filter layer, a photosensitive layer, and a metal layer are stacked sequentially. The microlens array 12 covers the side of the color filter layer that faces away from the photosensitive layer. Because the metal layer is located below the photodiodes, the spacing between adjacent photodiodes can be relatively reduced. Other structural features of the back-illuminated pixel array can be the same as those of the front-illuminated pixel array, and will not be described further here. After the incident light passes through the color filter layer, it directly reaches the photodiode through the light path of the photosensitive layer, without needing to pass through the metal layer, thus shortening the light path. Since the light path does not need to make room for the metal wiring of the metal layer, the distance between adjacent pixels can be appropriately shortened.

[0046] In one possible implementation, the microlenses in the microlens array 12 can correspond one-to-one with the photosensitive units in the image sensor 11, so that all incident light can be transmitted to the photosensitive units of the image sensor 11 through the microlenses. For example, the optical axis of the microlens can coincide with the center line of the corresponding color filter layer and the center line of the corresponding photodiode. In another possible implementation, one microlens in the microlens array 12 can correspond to a group of photosensitive units in the image sensor 11. Here, "a group of photosensitive units" can be, for example, a group of RGBW color filter layers and its corresponding group of photodiodes. For example, a microlens can correspond to a group of RGBW color filter layers, and each color filter in the group of RGBW color filter layers corresponds to one photodiode.

[0047] By setting up the microlens array 12, the incident light can be converged by adjusting its angle, allowing it to be focused on different photosensitive units in the image sensor 11, thereby reducing crosstalk between adjacent photosensitive units in the image sensor 11. Furthermore, setting up the microlens array 12 also helps to increase photoelectric conversion efficiency and improve image quality. It is worth noting that because the microlens array 12 has a low manufacturing cost, it also helps to reduce the production cost of the camera module.

[0048] In other embodiments, reference is made to Figure 3 and Figure 4 The microlens array 12 may further include a first array layer 121 and a second array layer 123 stacked together, and both the first array layer 121 and the second array layer 123 include microlenses arranged in an array. The first array layer 121 is located on the side of the color filter layer opposite to the photosensitive layer, and a lens material 122 is covered on the first array layer 121. The side of the lens material 122 opposite to the first array layer 121 has a plane, and the second array layer 123 covers this plane.

[0049] For example, refer to Figure 3The microlenses in the second array layer 123 can be located between two adjacent microlenses in the first array layer 121, and the refractive index of the microlenses in the second array layer 123 is greater than that of the microlenses in the first array layer 121. With this configuration, external light rays incident at large angles can have their angles controlled by the microlenses in the second array layer 123, allowing the light rays to enter different photosensitive units in the image sensor 11, thereby reducing crosstalk between adjacent photosensitive units in the image sensor 11. Furthermore, this configuration also helps to avoid the loss of light rays incident at large angles, thus increasing the photoelectric conversion efficiency.

[0050] For example, refer to Figure 4 The lens material 122 can have a thickness parallel to the optical axis of the microlens. The curvature of the microlens in the second array layer 123 can be greater than the curvature of the microlens in the first array layer 121, so that the effective depth of focus of the microlens in the second array layer 123 is less than or equal to half the thickness of the lens material 122. With this configuration, some incident light can be guided through the microlenses in the second array layer 123 to different sides of the microlenses in the first array layer 121, and then converged by the microlenses in the first array layer 121, which helps to reduce crosstalk between adjacent photosensitive units in the image sensor 11.

[0051] In this embodiment, an optical matching medium 30 is provided between the objective lens 202 and the microlens array 12. The refractive index of the optical matching medium 30 is greater than that of air. Since the wavelength of light is shorter when it propagates in the optical matching medium 30 with a higher refractive index, the diameter of the corresponding image is smaller, thereby improving the resolution between adjacent images.

[0052] For example, the end of the optical matching medium 30 near the objective lens 202 is in contact with the objective lens 202, and the end of the optical matching medium 30 near the microlens array 12 is in contact with the microlens array 12. This ensures that incident light, after passing through the objective lens 202, directly enters the optical matching medium 30 and then directly enters the microlens array 12, thereby preventing light from propagating in the air. This, in turn, avoids reducing the refractive index of the propagation medium between the objective lens 202 and the microlenses, and prevents a decrease in the resolution of the camera module.

[0053] The optical matching medium 30 can be a solid or a liquid. When the optical matching medium 30 is a solid, it can be placed inside the sealed cavity 301, with the end face of the optical matching medium 30 near the objective lens 202 abutting against the objective lens 202 and the end face of the optical matching medium 30 near the microlens array 12 abutting against the microlens array 12. This also helps to prevent the optical matching medium 30 from shaking inside the sealed cavity 301.

[0054] Reference Figure 1 In some embodiments, when the optical matching medium 30 is a liquid, the body 10 may be provided with a first opening 41 and a second opening 42. The first opening 41 is configured to allow the liquid in the optical matching medium 30 to enter or exit the sealed cavity 301, and the second opening 42 is configured to cooperate with the first opening 41 to allow the liquid in the optical matching medium 30 to enter or exit the sealed cavity 301. For example, the first opening 41 may be flush with the bottom surface of the sidewall of the body 10, and the second opening 42 may be flush with the top surface of the sidewall of the body 10. During the process of injecting liquid from the optical matching medium 30 into the sealed cavity 301, the liquid can enter the sealed cavity 301 through the first opening 41, while the gas (e.g., air) in the sealed cavity 301 is discharged through the second opening 42 until the liquid fills the sealed cavity 301. Conversely, during the process of discharging liquid from the optical matching medium 301, the liquid can be discharged from the sealed cavity 301 through the first opening 41, while external gas (e.g., air) can enter the sealed cavity 301 through the second opening 42, until the liquid is completely discharged from the sealed cavity 301. It should be noted that when the optical matching medium 30 includes liquid, the liquid in the optical matching medium 30 can be replaced as needed to match the resolution of the image sensor 11.

[0055] Reference Figure 2 In other embodiments, when the optical matching medium 30 is a liquid, the body 10 is provided with a first opening 41 and the cover 20 is provided with a second opening 42. The first opening 41 is configured to allow the liquid in the optical matching medium 30 to enter or exit the sealed cavity 301, and the second opening 42 is configured to cooperate with the first opening 41 to allow the liquid in the optical matching medium 30 to enter or exit the sealed cavity 301. For example, the cover plate 201 of the cover body 20 has a second opening 42 penetrating through it, and the bottom wall of the body 10 has a first opening 41 penetrating through it. During the process of injecting liquid from the optical matching medium 30 into the sealing cavity 301, the liquid can enter the sealing cavity 301 through the first opening 41, while the gas in the sealing cavity 301 is discharged through the second opening 42 until the liquid fills the sealing cavity 301. In addition, during the process of discharging liquid from the optical matching medium 30 into the sealing cavity 301, the liquid can be discharged from the sealing cavity 301 through the first opening 41, and external gas (e.g., air) can enter the sealing cavity 301 through the second opening 42 until the liquid is completely discharged from the sealing cavity 301. It should be noted that when the optical matching medium 30 includes liquid, the liquid in the optical matching medium 30 can be replaced as needed to match the resolution of the image sensor 11.

[0056] For example, the microlens array 12 abuts against the surface of the image sensor 11, thereby sealing the image sensor 11 and preventing it from contacting the optical matching medium 30, thus preventing damage to the image sensor 11. Of course, in some other embodiments, an encapsulation layer may also be provided between the microlens array 12 and the image sensor 11. The material of the encapsulation layer may include one or more of the following: silicone, PMMA (polymethyl methacrylate, acrylic glass), FEP (perfluoroethylene propylene copolymer), EVA (ethylene-vinyl acetate copolymer), EMA (ethylene / vinyl acetate copolymer), and PVB (polyvinyl butyral). By providing an encapsulation layer, direct contact between the image sensor 11 and the optical matching medium 30 is avoided, further preventing damage to the image sensor 11.

[0057] This disclosure provides a camera module including a body 10 and a cover 20, which together form a sealed cavity 301. An image sensor 11 and a microlens array 12 are disposed within the sealed cavity 301. An optical matching medium 30 is filled within the sealed cavity 301. The cover 20 includes an objective lens 202, the centerline of the image sensor 11 coincides with the optical axis of the objective lens 202, the microlens array 12 is located between the image sensor 11 and the objective lens 202, and an optical matching medium 30 is provided between the objective lens 202 and the microlens array 12. The refractive index of the optical matching medium 30 is greater than that of air. Compared to related technologies where the medium between the objective lens 202 and the image sensor 11 is air, this disclosure, by providing a high-refractive-index optical matching medium 30 between the objective lens 202 and the microlens array 12, helps to shorten the wavelength of light in the medium, thereby reducing the diameter of the corresponding image. This allows for the placement of smaller, more precisely-pitched photosensitive units on the image sensor, ultimately improving the resolution of the camera module.

[0058] For example, the refractive index of the microlens array 12 can be greater than or equal to the refractive index of the optical matching medium 30, which helps to further avoid the loss of incident light, improve the light collection effect, and thus improve the imaging quality of the camera module.

[0059] In this embodiment, the camera module further includes a lens assembly located on the side of the objective lens 202 facing away from the sealed cavity 301. The lens assembly is detachably connected to the body 10 or the cover 20. The lens assembly may include several lenses with different functions, such as fluorite lenses, UD lenses (Ultra Low Dispersion lenses), etc., which are combined to achieve the light-adjusting function of the camera module. For example, the lenses in the lens assembly can be arranged sequentially along their optical axis. In some embodiments, the lens assembly can be disposed inside the lens barrel, and the lens barrel and the body 10 can be detachably connected by means of threaded connection, snap-fit ​​connection, or other similar methods. In some other embodiments, the lens barrel and the body 10 or the cover 20 can also be connected by a telescopic structure. By providing a telescopic structure, the distance between the lens barrel and the objective lens 202 can be adjusted, thereby adjusting the distance between the lens assembly and the objective lens 202, and adaptively adjusting the imaging effect of the camera module.

[0060] Continue to refer to Figure 5 In some other embodiments, the optical matching medium 30 may further include a first medium 31 and a second medium 32, which are distributed along the direction from the objective lens 202 to the microlens array 12. The first medium 31 is located on the side of the second medium 32 closer to the objective lens 202. The refractive indices of both the first medium 31 and the second medium 32 are greater than that of air. After light enters the first medium 31 and the second medium 32 with their higher refractive indices, the wavelength of the light is shorter, resulting in a smaller diameter of the corresponding image, thereby improving the resolution between adjacent images. In some embodiments, the refractive indices of the first medium 31 and the second medium 32 are different, which helps to adjust the wavelength of the incident light within the optical matching medium 30, thereby adjusting the resolution of the camera module and further improving the collection effect of the incident light.

[0061] In some embodiments, both the first medium 31 and the second medium 32 can be solids. For example, the first medium 31 and the second medium 32 can be optical lenses. Exemplarily, the side of the first medium 31 facing away from the second medium 32 contacts the objective lens 202, and the side of the second medium 32 facing away from the second medium 32 contacts the microlens array 12. The first medium 31 and the second medium 32 are in contact with each other, so that incident light, after passing through the objective lens 202, sequentially passes through the first medium 31, the second medium 32, and the microlens array 12 until it is received by the image sensor 11. In a specific implementation, the contact surfaces between the first medium 31 and the second medium 32 are both planar, facilitating contact between them and preventing the entry of an air layer between them, thus promoting light propagation between the first medium 31 and the second medium 32.

[0062] In some other embodiments, one of the first medium 31 and the second medium 32 is a solid, and the other is a liquid. For example, when the first medium 31 is a liquid and the second medium 32 is a solid, the side of the second medium 32 facing away from the objective lens 202 contacts the microlens array 12, and the sidewall of the second medium 32 is also sealed to the sidewall of the body 10, so that the second medium 32, the body 10, and the objective lens 202 can form a sealed space, and the first medium 31 fills the sealed space. For example, when the first medium 31 is a solid and the second medium 32 is a liquid, the side of the first medium 31 facing away from the microlens array 12 contacts the objective lens 202, and the sidewall of the first medium 31 is also sealed to the sidewall of the body 10, so that the first medium 31, the body 10, and the microlens array 12 can form a sealed space, and the second medium 32 fills the sealed space.

[0063] Continue to refer to Figure 5 In an embodiment where the first medium 31 is a liquid and the second medium 32 is a solid, a first opening 41 and a second opening 42 are also provided on the body 10 where the first medium 31 is located. For example, the first opening 41 can be flush with the top surface of the second medium 32, and the second opening 42 can be flush with the top surface of the side wall of the body 10. This facilitates the flow of liquid through the first opening 41 and the discharge of air through the second opening 42 until the liquid fills the sealed cavity 301. It is worth noting that sealing plugs can also be provided in the first opening 41 and the second opening 42 to prevent liquid from leaking out from the first opening 41 or the second opening 42.

[0064] In one specific embodiment, when the optical matching medium 30 includes a liquid, the liquid may include one or more of water, glycerin, cedar oil, benzene, and carbon tetrachloride. Specifically, water has a refractive index of 1.33, cedar oil has a refractive index of 1.51, glycerin has a refractive index of 1.47, benzene has a refractive index of 1.50, and carbon tetrachloride has a refractive index of 1.46. By using liquids with different refractive indices, the refractive index of the optical matching medium 30 can be adjusted, thereby adjusting the resolution of the camera module. For example, assuming the refractive index of the optical matching medium 30 is n (n>1), then compared to a typical camera module (e.g., with a resolution of approximately 0.5 μm), the camera module provided in this embodiment can achieve a resolution of approximately 0.5 / n μm; in this case, an image sensor with a higher resolution can be used to achieve a higher resolution for the camera module. For example, when the optical matching medium 30 is water (refractive index 1.33), the resolution of the camera module can reach about 0.38um; when the optical matching medium 30 is cedar oil (refractive index 1.51), the resolution of the camera module can reach about 0.33um.

[0065] For example, the refractive index of the microlens array 12 can be greater than or equal to the refractive index of the second medium 32 in the optical matching medium 30, which helps to further avoid the loss of incident light, improve the light collection effect, and thus improve the imaging quality of the camera module.

[0066] Reference Figure 6 In some embodiments, the optical matching medium 30 may further include a third medium 33, which is located between the first medium 31 and the second medium 32. The first medium 31 and the second medium 32 are both liquids, while the third medium 33 is a solid. By providing the third medium 33, the sidewalls of the third medium 33 are sealed to the sidewalls of the body 10, allowing the third medium 33, the body 10, and the objective lens 202 to form a sealed space filled with the first medium 31. The third medium 33, the body 10, and the microlens array 12 can also form a sealed space filled with the second medium 32, thus separating the first medium 31 and the second medium 32. After passing through the objective lens 202, the incident light sequentially passes through the first medium 31, the third medium 33, the second medium 32, and the microlens array 12 until it is received by the image sensor 11.

[0067] In some embodiments, the refractive indices of the first medium 31, the second medium 32, and the third medium 33 can all be different, which is beneficial for adjusting the refractive index of the incident light in the optical matching medium 30, thereby adjusting the resolution of the camera module and further improving the collection effect of the incident light. Of course, in some other embodiments, the refractive indices of the first medium 31, the second medium 32, and the third medium 33 can also be adjusted according to the actual usage.

[0068] In some other embodiments, the first medium 31, the second medium 32, and the third medium 33 can all be solids. For example, the materials of the first medium 31, the second medium 32, and the third medium 33 can be optical glass or resin. The contact surfaces between the first medium 31 and the third medium 33 can be planar, and the contact surfaces between the second medium 32 and the third medium 33 can be planar, to prevent air layers from entering between the first medium 31 and the third medium 33, and between the second medium 32 and the third medium 33, which is beneficial for the propagation of light between the first medium 31 and the third medium 33, and between the second medium 32 and the third medium 33.

[0069] Of course, in some other embodiments, one of the first medium 31, the second medium 32, and the third medium 33 is a liquid, and the others are solids. For example, the first medium 31 and the second medium 32 are solids, and the third medium 33 is a liquid, wherein the first medium 31, the second medium 32 and the body 10 form a closed space, and the third medium 33 fills the closed space.

[0070] Continue to refer to Figure 6 In an embodiment where the first medium 31 and the second medium 32 are liquids and the third medium 33 is a solid, a first opening 41 and a second opening 42 are also provided on the side wall of the body 10 where the first medium 31 is located. The first opening 41 is configured to allow the liquid in the optical matching medium 30 to enter or exit into the body 10 where the first medium 31 is located, and the second opening 42 is configured to cooperate with the first opening 41 to allow the liquid in the optical matching medium 30 to enter or exit from the body 10 where the first medium 31 is located; a first opening 41 and a second opening 42 are also provided on the side wall of the body 10 where the second medium 32 is located. The first opening 41 is configured to allow the liquid in the optical matching medium 30 to enter or exit into the body 10 where the second medium 32 is located, and the second opening 42 is configured to cooperate with the first opening 41 to allow the liquid in the optical matching medium 30 to flow out from the body 10 where the second medium 32 is located. As described in the above embodiments, on the body 10 where the first medium 31 is located, the first opening 41 is flush with the top surface of the third medium 33, and the second opening 42 is flush with the top surface of the side wall of the body 10; on the body 10 where the second medium 32 is located, the second opening 42 is flush with the bottom surface of the third medium 33, and the first opening 41 is flush with the bottom surface of the side wall of the body 10.

[0071] Reference Figure 5 and Figure 6 In this embodiment, the refractive index of the optical matching medium 30 gradually increases in the direction parallel to the optical axis of the objective lens 202 and pointing from the objective lens 202 to the microlens array 12. This direction, parallel to the optical axis of the objective lens 202 and pointing from the objective lens 202 to the microlens array 12, is the X direction in the figure. The materials in the first medium 31, the second medium 32, and the third medium 33 are uniformly distributed to ensure that their refractive indices are equal everywhere: the refractive index of the first medium 31 can be, for example, n1; the refractive index of the second medium 32 can be, for example, n2; and the refractive index of the third medium 33 can be, for example, n3. In the embodiment where the optical matching medium 30 includes the first medium 31 and the second medium 32, the refractive index n2 of the second medium 32 is greater than the refractive index n1 of the first medium 31, thereby causing the refractive indices of the first medium 31 and the second medium 32 to gradually increase along the X direction in the figure. In the embodiment where the optical matching medium 30 includes a first medium 31, a second medium 32, and a third medium 33, the refractive index n2 of the second medium 32 is greater than the refractive index n3 of the third medium 33, and the refractive index n3 of the third medium 33 is greater than the refractive index n1 of the first medium 31. This results in the refractive indices of the first medium 31, the third medium 33, and the second medium 32 gradually increasing along the X direction in the figure. Through this arrangement, the wavelength of the incident light gradually shortens after entering the optical matching medium 30, thereby gradually improving the resolution of the camera module.

[0072] Reference Figure 5and Figure 6 In this embodiment, the refractive indices of the first medium 31, the second medium 32, and the third medium 33 gradually increase in the direction parallel to the optical axis of the objective lens 202 and pointing from the objective lens 202 to the microlens array 12. This direction, parallel to the optical axis of the objective lens 202 and pointing from the objective lens 202 to the microlens array 12, is the X direction in the figure. By adjusting the densities of the first medium 31, the second medium 32, and the third medium 33, the refractive index of the first medium 31 in the X direction can gradually increase from c1 to c2, the refractive index of the third medium 33 in the X direction can gradually increase from c3 to c4, and the refractive index of the second medium 32 in the X direction can gradually increase from c5 to c6. In embodiments where the optical matching medium 30 includes the first medium 31 and the second medium 32, the maximum refractive index c2 in the first medium 31 is less than the minimum refractive index c5 in the second medium 32, thereby causing the refractive indices of the first medium 31 and the second medium 32 to gradually increase in the X direction in the figure. In the embodiment where the optical matching medium 30 includes a first medium 31, a second medium 32, and a third medium 33, the maximum refractive index c2 in the first medium 31 is less than the minimum refractive index c3 in the third medium 33, and the maximum refractive index c4 in the third medium 33 is less than the minimum refractive index c5 in the second medium 32. This results in the refractive indices of the first medium 31, the third medium 33, and the second medium 32 gradually increasing along the X direction in the figure. Through this arrangement, the wavelength of the incident light gradually shortens after entering the optical matching medium 30, thereby gradually improving the resolution of the camera module.

[0073] For example, the refractive index of the microlens array 12 can be greater than or equal to the maximum refractive index of the second medium 32 in the optical matching medium 30, which helps to further avoid the loss of incident light, improve the light collection effect, and thus improve the imaging quality of the camera module.

[0074] It is worth noting that the optical matching medium 30 in this embodiment may include more than three media. The specific number of media can be adjusted according to actual usage needs, and this embodiment does not limit it.

[0075] Reference Figure 7 , Figure 2 as well as Figure 1 This disclosure also provides an electronic device including a camera module 51 as described in any of the above embodiments, the camera module 51 being configured to acquire optical images. The electronic device further includes a display 52, a processor 53, and a memory 54. The display module is electrically connected to the camera module 51, the memory 54 is electrically connected to the processor 53, and the processor 53 is also electrically connected to the camera module 51. The processor 53 can be configured to convert digital signals into digital images, and the memory 54 can be configured to store the digital images, enabling the display module to display the optical images.

[0076] It is worth noting that the electronic devices provided in the embodiments of this disclosure may include personal computers, portable display devices, smartphones, etc.

[0077] The electronic device provided in this embodiment includes a camera module 51, which includes a body 10 and a cover 20, which cooperate to form a sealed cavity 301; an image sensor 11 and a microlens array 12 are disposed in the sealed cavity 301; and an optical matching medium 30 is filled in the sealed cavity 301. The cover 20 includes an objective lens 202, the centerline of the image sensor 11 coincides with the optical axis of the objective lens 202, the microlens array 12 is located between the image sensor 11 and the objective lens 202, and an optical matching medium 30 is provided between the objective lens 202 and the microlens array 12. The refractive index of the optical matching medium 30 is greater than that of air. In contrast to related technologies where the medium between the objective lens 202 and the image sensor 11 is air, this embodiment of the present disclosure provides a high-refractive-index optical matching medium 30 between the objective lens 202 and the microlens array 12. This helps to shorten the wavelength of light in the medium, thereby reducing the diameter of the corresponding image. As a result, a smaller photosensitive unit with a smaller pitch can be set on the image sensor, which in turn helps to improve the resolution of the camera module.

[0078] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is merely an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A camera module, characterized in that, include: The body and the cover are fitted together to form a sealed cavity; An image sensor and a microlens array are disposed within the sealed cavity; An optical matching medium is filled into the sealed cavity; The cover includes an objective lens, the centerline of the image sensor coincides with the optical axis of the objective lens, the microlens array is located between the image sensor and the objective lens, and the optical matching medium is located between the objective lens and the microlens array. The refractive index of the optical matching medium is greater than that of air. The optical matching medium includes a first medium and a second medium, which are distributed along the direction from the objective lens to the microlens array. The first medium is located on the side of the second medium closer to the objective lens, and the refractive indices of the first medium and the second medium are different.

2. The camera module according to claim 1, characterized in that, Both the first medium and the second medium are solids.

3. The camera module according to claim 1, characterized in that, One of the first medium and the second medium is a solid, and the other of the first medium and the second medium is a liquid.

4. The camera module according to claim 1, characterized in that, The optical matching medium further includes a third medium located between the first medium and the second medium, wherein the first medium and the second medium are both liquids and the third medium is a solid.

5. The camera module according to claim 1, characterized in that, The refractive index of the optical matching medium gradually increases in a direction parallel to the optical axis of the objective lens and pointing from the objective lens to the microlens array.

6. The camera module according to claim 4, characterized in that, In a direction parallel to the optical axis of the objective lens and pointing from the objective lens to the microlens array, the refractive indices of the first medium, the third medium, and the second medium gradually increase.

7. The camera module according to claim 1, characterized in that, When the optical matching medium includes a liquid, the body is provided with a first opening and a second opening. The first opening is configured to allow the liquid in the optical matching medium to enter or exit the sealed cavity, and the second opening is configured to cooperate with the first opening to allow the liquid in the optical matching medium to enter or exit the sealed cavity.

8. The camera module according to claim 1, characterized in that, When the optical matching medium includes a liquid, the body is provided with a first opening and the cover is provided with a second opening. The first opening is configured to allow the liquid in the optical matching medium to enter or exit the sealed cavity, and the second opening is configured to cooperate with the first opening to allow the liquid in the optical matching medium to enter or exit the sealed cavity.

9. The camera module according to any one of claims 1-8, characterized in that, The end of the optical matching medium near the objective lens is in contact with the objective lens, and the end of the optical matching medium near the microlens array is in contact with the microlens array.

10. The camera module according to any one of claims 1-8, characterized in that, The refractive index of the microlens array is greater than or equal to the refractive index of the optical matching medium.

11. The camera module according to any one of claims 1-8, characterized in that, When the optical matching medium comprises a liquid, the liquid includes one or more of water, glycerin, cedar oil, benzene, and carbon tetrachloride.

12. The camera module according to any one of claims 1-8, characterized in that, The image sensor includes a charge-coupled device or a complementary metal-oxide-semiconductor device.

13. The camera module according to any one of claims 1-8, characterized in that, It also includes a lens assembly located on the side of the objective lens away from the sealed cavity, and the lens assembly is detachably connected to the body or the cover.

14. The camera module according to any one of claims 1-8, characterized in that, The microlens array includes multiple microlenses arranged in an array, and the image sensor includes multiple photosensitive units arranged in an array, with each microlens corresponding to one of the photosensitive units.

15. An electronic device, characterized in that, The electronic device includes a camera module as described in any one of claims 1-14, the camera module being configured to acquire optical images; the electronic device further includes a display module electrically connected to the camera module, the display module being configured to display the optical images.

Images