Under-display ultrasonic module, bonding structure and electronic equipment

Abstract

This application provides an under-display ultrasonic module, an adhesive structure, and an electronic device. The under-display ultrasonic module includes an under-display ultrasonic sensor and an adhesive structure. The adhesive structure includes a first adhesive layer, a support layer, and a second adhesive layer. The first and second adhesive layers are located on opposite sides of the support layer in the thickness direction. The second adhesive layer is bonded to the under-display ultrasonic sensor, and the first adhesive layer is used to bond to the carbon fiber reinforcing layer of the screen, allowing the under-display ultrasonic module to be bonded under the screen. The thickness of the first adhesive layer ranges from 3µm to 10µm, the thickness of the support layer ranges from 17µm to 24µm, and the thickness of the second adhesive layer ranges from 5µm to 10µm. The technical solution of this application specifically improves the usage effect and performance of the under-display ultrasonic module in carbon fiber screens, realizing the possibility of large-scale application of under-display ultrasonic detection in electronic devices with carbon fiber screens.

Description

Technical Field

[0001] This application relates to the field of ultrasonic technology, and in particular to an under-screen ultrasonic module, an adhesive structure, and an electronic device. Background Technology

[0002] Currently, ultrasonic technology is being used more and more widely, for example, in under-display ultrasonic biometric detection via an under-display ultrasonic module. This under-display ultrasonic module is typically attached to the underside of the screen. Due to users' higher demands for electronic device screens, foldable screens have emerged.

[0003] Foldable screens have thin and flexible layers, leading to significant energy attenuation of ultrasonic waves during penetration due to absorption by these layers. Furthermore, to enhance screen strength, the reinforcing materials for foldable screens typically require high strength and good bending performance. Carbon fiber, with its excellent strength and bending properties, along with its significant weight advantage, is suitable for reinforcing layers in foldable screens. However, carbon fiber reinforcement layers have a much higher acoustic impedance than the screen body material, resulting in substantial energy loss of ultrasonic waves at the interface between the reinforcement layer and the screen.

[0004] Therefore, providing a new technical solution for under-display ultrasonic modules to meet the ultrasonic signal transmission requirements of screens using carbon fiber reinforcement layers (also known as carbon fiber screens) has become a technical problem that needs to be solved. Utility Model Content

[0005] This application provides an under-screen ultrasonic module, an adhesive structure, and an electronic device.

[0006] According to a first aspect of the embodiments of this application, an under-display ultrasonic module is provided. The under-display ultrasonic module includes: an under-display ultrasonic sensor and an adhesive structure; the adhesive structure includes a first adhesive layer, a support layer, and a second adhesive layer, the first adhesive layer and the second adhesive layer being located on opposite sides of the support layer in the thickness direction, wherein the second adhesive layer is bonded to the under-display ultrasonic sensor, and the first adhesive layer is used to bond to a carbon fiber reinforcing layer of the screen, so that the under-display ultrasonic module can be bonded under the screen; wherein the thickness of the first adhesive layer ranges from 3µm to 10µm, the thickness of the support layer ranges from 17µm to 24µm, and the thickness of the second adhesive layer ranges from 5µm to 10µm.

[0007] In some optional embodiments, the screen is a foldable screen, the thickness of the carbon fiber reinforcement layer ranges from 100um to 175um, and the resonant frequency of the screen ranges from 5MHz to 20MHz.

[0008] In some optional embodiments, the under-screen ultrasonic module satisfies at least one of the following conditions:

[0009] The first adhesive layer includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer, or the first adhesive layer is a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked.

[0010] The second adhesive layer includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer, or the second adhesive layer is a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked.

[0011] The thickness of the first adhesive layer is equal to the thickness of the second adhesive layer;

[0012] The acoustic impedance of the support layer is greater than the acoustic impedance of the first adhesive layer and the acoustic impedance of the second adhesive layer.

[0013] The support layer is a metal layer;

[0014] The under-display ultrasonic sensor is an under-display ultrasonic fingerprint sensor, and the under-display ultrasonic module is an under-display ultrasonic fingerprint module.

[0015] In some alternative embodiments, the support layer is a copper foil layer.

[0016] In some optional embodiments, the thickness of the first adhesive layer is 6 μm, the thickness of the support layer is 23 μm, and the thickness of the second adhesive layer is 6 μm; or, the thickness of the first adhesive layer is 6 μm, the thickness of the support layer is 18 μm, and the thickness of the second adhesive layer is 6 μm.

[0017] In some optional embodiments, the under-display ultrasonic sensor includes: a substrate, a first electrode, an acoustic layer, and a second electrode; the first electrode is located on the substrate, and the acoustic layer is located between the first electrode and the second electrode; the second electrode is used to be excited by an excitation signal to excite the acoustic layer to emit an ultrasonic signal; the first electrode is used to receive an ultrasonic detection signal generated between the second electrode and the first electrode when the returned ultrasonic signal acts on the acoustic layer.

[0018] In some alternative embodiments, the under-display ultrasonic sensor further includes a protective layer that covers at least a portion of the second electrode.

[0019] In some alternative embodiments, the second adhesive layer is bonded to the substrate, or the second adhesive layer is bonded to the protective layer.

[0020] According to a second aspect of the embodiments of this application, an adhesive structure is provided. The adhesive structure is used to adhere an under-display ultrasonic sensor to the underside of a screen. The adhesive structure includes: a first adhesive layer, a support layer, and a second adhesive layer. The first adhesive layer and the second adhesive layer are respectively located on opposite sides of the support layer in the thickness direction. The second adhesive layer is used to adhere to the under-display ultrasonic sensor, and the first adhesive layer is used to adhere to a carbon fiber reinforcing layer of the screen. The thickness of the first adhesive layer ranges from 3µm to 10µm, the thickness of the support layer ranges from 17µm to 24µm, and the thickness of the second adhesive layer ranges from 5µm to 10µm. According to a third aspect of the embodiments of this application, an electronic device is provided. The electronic device includes a screen, a carbon fiber reinforcing layer, and an under-display ultrasonic module as described in any one of the first aspects. The first adhesive layer of the under-display ultrasonic module is adhered to the carbon fiber reinforcing layer to adhere the under-display ultrasonic module to the underside of the screen.

[0021] The under-display ultrasonic module in this embodiment includes an under-display ultrasonic sensor and an adhesive structure. The adhesive structure comprises a first adhesive layer with a thickness ranging from 3µm to 10µm, a support layer with a thickness ranging from 17µm to 24µm, and a second adhesive layer with a thickness ranging from 5µm to 10µm. The first and second adhesive layers are located on opposite sides of the support layer in the thickness direction. The second adhesive layer on one side is bonded to the under-display ultrasonic sensor, and the first adhesive layer on the other side is bonded to the carbon fiber reinforcement layer of the screen. This allows the under-display ultrasonic module to be bonded to the underside of the screen. The thickness of each layer in the adhesive structure of the under-display ultrasonic module in this embodiment better adapts to the ultrasonic signal transmission requirements of the screen (also known as a carbon fiber screen) including the carbon fiber reinforcement layer. This facilitates acoustic impedance matching between the under-display ultrasonic module and the carbon fiber screen, reduces ultrasonic signal transmission loss, and effectively improves the performance and reliability of the under-display ultrasonic module in carbon fiber screens. This enables the large-scale application of under-display ultrasonic detection in electronic devices with carbon fiber screens. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application 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 only some embodiments recorded in the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1A A schematic diagram of an example under-screen ultrasonic module of this application is shown.

[0024] Figure 1B A schematic diagram of another example of an under-display ultrasonic module in this application is shown.

[0025] Figure 2A A schematic diagram of an example screen's stacked structure is shown.

[0026] Figure 2B It shows Figure 2A The frequency response of each resonant cavity in the screen stack.

[0027] Figure 3A This diagram illustrates a stacked structure in which an unoptimized under-display ultrasonic module is bonded to a carbon fiber reinforcement layer on the screen.

[0028] Figure 3B The frequency response of each resonant cavity in the unoptimized under-screen ultrasonic module is shown.

[0029] Figure 4 This illustration shows a stacked schematic diagram of an optimized under-screen ultrasonic module bonded to a carbon fiber reinforcement layer on the screen, according to an embodiment of this application.

[0030] Figure 5A The frequency response of the resonant cavity 7 of an optimized under-screen ultrasonic module, as exemplified in one embodiment of this application, is shown.

[0031] Figure 5B The frequency response of the resonant cavity 7 of an optimized under-screen ultrasonic module, as shown in another example of an embodiment of this application, is illustrated.

[0032] Figure 6 A schematic diagram of an example adhesive structure of this application is shown.

[0033] Figure 7A A schematic diagram of an example electronic device according to this application is shown.

[0034] Figure 7B A schematic diagram of another example of an electronic device in this application is shown.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1000, Under-display ultrasonic module; 100, Adhesive structure; 110, First adhesive layer; 120, Second adhesive layer; 130, Support layer; 200, Under-display ultrasonic sensor; 210, Substrate; 211, First electrode; 212, Second electrode; 213, Acoustic layer; 214, Protective layer; 300, Screen; 310, Carbon fiber reinforcement layer; 320, Screen body; 3201, First adhesive layer; 3202, Display panel layer; 3203, Second adhesive layer; 3204, Screen cover layer; 3205, Third adhesive layer; 3206, Screen protective film layer; 400, Electronic device; H1, Thickness of the first adhesive layer; H2, Thickness of the second adhesive layer; H3, Thickness of the support layer; H, Thickness of the carbon fiber reinforcement layer. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0038] According to a first aspect of the embodiments of this application, referring to... Figure 1A and Figure 1B As shown, this application provides an under-display ultrasonic module 1000, which includes: an under-display ultrasonic sensor 200 and an adhesive structure 100; the adhesive structure 100 includes a first adhesive layer 110, a support layer 130 and a second adhesive layer 120, the first adhesive layer 110 and the second adhesive layer 120 are respectively located on both sides of the support layer 130 in the thickness direction, wherein the second adhesive layer 120 is bonded to the under-display ultrasonic sensor 200, and the first adhesive layer 110 is used to bond to the carbon fiber reinforcing layer 310 of the screen 300, so that the under-display ultrasonic module can be bonded under the screen 300; wherein the thickness range of the first adhesive layer 110 is 3um to 10um, the thickness range of the support layer 130 is 17um to 24um, and the thickness range of the second adhesive layer 120 is 5um to 10um.

[0039] The under-display ultrasonic module 1000 in this embodiment includes an under-display ultrasonic sensor 200 and an adhesive structure 100. The adhesive structure 100 includes a first adhesive layer 110 with a thickness ranging from 3µm to 10µm, a support layer 130 with a thickness ranging from 17µm to 24µm, and a second adhesive layer 120 with a thickness ranging from 5µm to 10µm. The first adhesive layer 110 and the second adhesive layer 120 are located on opposite sides of the support layer 130 in the thickness direction. The second adhesive layer 120 on one side is bonded to the under-display ultrasonic sensor 200, and can be bonded to the carbon fiber reinforcing layer 310 of the screen 300 through the first adhesive layer 110 on the other side. The under-display ultrasonic module 1000 can be bonded to the underside of the screen 300. Through the thickness of each layer of the bonding structure 100 of the under-display ultrasonic module 1000 in this embodiment, it can better adapt to the ultrasonic signal transmission requirements of the screen including the carbon fiber reinforcement layer (also known as the carbon fiber screen). This is beneficial to achieving acoustic impedance matching between the under-display ultrasonic module 1000 and the carbon fiber screen, reducing the transmission loss of ultrasonic signals. Therefore, it effectively and specifically improves the usage effect and performance of the under-display ultrasonic module in the carbon fiber screen, improves the reliability and performance of under-display ultrasonic detection, and realizes the possibility of large-scale application of under-display ultrasonic detection in electronic devices with carbon fiber screens.

[0040] The following provides a detailed description of some optional embodiments of the under-screen ultrasonic module 1000 in this application.

[0041] Optionally, the under-display ultrasonic module 1000 can perform under-display ultrasonic detection, specifically, it can perform ultrasonic biometric detection above the screen 300. The under-display ultrasonic sensor 200 in this application can be any type of ultrasonic sensor, and correspondingly, the under-display ultrasonic module 1000 can be any type of ultrasonic module. For example, in some embodiments, the under-display ultrasonic sensor 200 can be an under-display ultrasonic fingerprint sensor, and the under-display ultrasonic module 1000 can be an under-display ultrasonic fingerprint module, whose detected biometric features may include fingerprint features.

[0042] Therefore, under-display ultrasonic fingerprint detection can be achieved through the under-display ultrasonic module 1000 in this embodiment. Since the under-display ultrasonic module 1000 can better adapt to the ultrasonic signal transmission requirements of the screen including the carbon fiber reinforcement layer (also known as the carbon fiber screen), and is conducive to achieving acoustic impedance matching between the under-display ultrasonic module and the carbon fiber screen, reducing the transmission loss of ultrasonic signals, the under-display ultrasonic module 1000 has good stacking performance when used in the carbon fiber screen, and the under-display ultrasonic module has good usage effect and performance in the carbon fiber screen. Therefore, the accuracy and reliability of under-display ultrasonic fingerprint detection are also good.

[0043] In other embodiments, the under-display ultrasonic sensor 200 may also be an under-display ultrasonic touch sensor or other types of sensors for detecting touch. Correspondingly, the under-display ultrasonic module 1000 may be an under-display ultrasonic touch detection module for detecting touch.

[0044] The following text uses the under-display ultrasonic sensor 200 as an example to illustrate the under-display ultrasonic fingerprint sensor.

[0045] The screen 300 in this application embodiment can be any screen with a carbon fiber reinforcement layer. For example, in some optional embodiments, the screen 300 can be, but is not limited to, a foldable screen.

[0046] In this embodiment, the under-display ultrasonic sensor 200 can adopt any structure. For example, in some optional embodiments, refer to... Figure 1A , Figure 1B As shown, the under-display ultrasonic sensor 200 includes: a substrate 210, a first electrode 211, an acoustic layer 213, and a second electrode 212. The first electrode 211 is located on the substrate 210, and the acoustic layer 213 is located between the first electrode 211 and the second electrode 212. The second electrode 212 is used to be excited by an excitation signal to induce the acoustic layer 213 to emit ultrasonic signals. The first electrode 211 is used to receive the ultrasonic detection signal generated between the second electrode 212 and the first electrode 211 when the returned ultrasonic signal acts on the acoustic layer 213.

[0047] Based on this, the structure of the optional under-display ultrasonic sensor 200 in this application enables the under-display ultrasonic module 1000 to effectively realize the function of under-display ultrasonic feature detection when it is bonded to the underside of the screen 300 (carbon fiber screen, such as carbon fiber folding screen).

[0048] Optionally, the substrate 210 can be used to deploy part of the circuit structure of the under-display ultrasonic sensor 200. Optionally, the substrate 210 can be a silicon substrate, a glass substrate, a PET (Polyethylene Terephthalate) layer, or a PI (Polyimide) layer, etc.

[0049] Optionally, one of the first electrode 211 and the second electrode 212 can be a bottom electrode and the other a top electrode. For example, the first electrode 211 can be a bottom electrode and the second electrode 212 can be a top electrode. The first electrode 211 and the second electrode 212 can be made of any material, such as metal, without limitation. For example, the first electrode 211 can be an aluminum electrode or a copper electrode (but is not limited to these), and can include multiple sub-electrodes arranged in an array on the substrate 210, each sub-electrode being considered as a "pixel". For example, the second electrode 212 can be a silver electrode.

[0050] Optionally, the acoustic layer 213 may be a piezoelectric material layer, which generates ultrasonic signal transmission and reception based on the piezoelectric effect (the piezoelectric material layer may include, but is not limited to, at least one of PVDF (polyvinylidene difluoride), lead zirconate titanate, and lithium niobate; the PVDF material may include PVDF, PVDF copolymer, etc.).

[0051] Optionally, the excitation signal applied to the second electrode 212 can be a pulse excitation signal, such as a pulse voltage signal. The excitation signal can be input from an external circuit. By applying the excitation signal to the second electrode 212, a voltage difference is formed between the second electrode 212 and the first electrode 211, thereby exciting the acoustic layer 213 to emit an ultrasonic signal upwards toward the screen 300. The first electrode 211 can receive the ultrasonic detection signal generated between the second electrode 212 and the first electrode 211 when the returned ultrasonic signal acts on the acoustic layer 213. The ultrasonic detection signal can be an electrical signal generated by the returned ultrasonic signal acting on the acoustic layer 213. Optionally, the ultrasonic detection signal received by the first electrode 211 can be used to realize ultrasonic biometric detection (such as ultrasonic fingerprint detection). Optionally, the ultrasonic detection signal can be used to generate an ultrasonic image, and ultrasonic biometric detection can be realized based on the ultrasonic image. For example, taking ultrasonic fingerprint detection as an example, the ultrasonic detection signal can be used to generate an ultrasonic fingerprint image, and fingerprint detection can be performed based on the ultrasonic fingerprint image.

[0052] Optionally, the process of generating an ultrasonic fingerprint image and performing fingerprint detection based on the ultrasonic fingerprint image described above can be implemented by a controller in an electronic device installed in the under-display ultrasonic module 1000 (which can be electrically connected to the under-display ultrasonic sensor 200 of the under-display ultrasonic module 1000); or, in other optional embodiments, the process of generating an ultrasonic fingerprint image can also be implemented by a processing unit in the under-display ultrasonic module 1000, which sends the generated ultrasonic fingerprint image to the controller in the electronic device, and the controller then performs fingerprint detection based on the ultrasonic fingerprint image.

[0053] In some alternative embodiments, refer to Figure 1A , Figure 1B As shown, the under-display ultrasonic sensor 200 may further include a protective layer 214 that covers at least a portion of the second electrode 212. Thus, the protective layer 214 can protect at least a portion of the second electrode 212, for example, preventing water and oxygen corrosion and other adverse environmental factors, thereby improving the lifespan of the under-display ultrasonic sensor 200.

[0054] Optionally, the protective layer 214 can protect the second electrode 212, the acoustic layer 213, and the first electrode 211 to better protect the under-screen ultrasonic sensor 200, avoid water and oxygen corrosion and other adverse environmental factors, and improve the lifespan of the under-screen ultrasonic sensor 200.

[0055] Optionally, the protective layer 214 can be an insulating layer, made of any material. For example, it can be a protective layer made of inorganic insulating materials such as silicon oxide and silicon nitride, or it can be a protective layer made of organic insulating materials such as polyimide and epoxy resin. In some embodiments, the protective layer 214 can be an ink layer. The choice can be made according to actual needs, and no specific limitations are imposed here.

[0056] It should be understood that the principle and optional structure of the under-display ultrasonic sensor 200 (such as an under-display ultrasonic fingerprint sensor) can also be understood according to relevant technologies, and will not be elaborated here. This solution can be implemented using an under-display ultrasonic sensor of any structure.

[0057] In this embodiment, the under-display ultrasonic sensor 200 is bonded to the second adhesive layer 120 of the adhesive structure 100, and the first adhesive layer 110 of the adhesive structure 100 can be bonded to the carbon fiber reinforcing layer 310 of the screen 300 (e.g., a foldable screen), so that when the under-display ultrasonic module 1000 is used, it can be bonded to the underside of the screen 300.

[0058] The adhesive structure 100 in this embodiment can be used to fix the under-screen ultrasonic module 1000 and the screen 300, and can also serve as an acoustic impedance matching layer to achieve better ultrasonic energy transmission.

[0059] Optionally, when the under-display ultrasonic module 1000 is bonded to the carbon fiber reinforcing layer 310 of the screen 300 (e.g., a foldable screen) to be bonded below the screen 300, the bonding structure 100 can serve as an acoustic impedance matching layer between the under-display ultrasonic sensor 200 and the screen 300 (including the carbon fiber reinforcing layer 310). Therefore, its structure is very important. In this embodiment, the lamination performance of the bonding structure 100 is improved by optimizing the thickness of each layer.

[0060] In some alternative embodiments, refer to Figure 1A As shown, the second adhesive layer 120 of the adhesive structure 100 can be bonded to the substrate 210 of the under-display ultrasonic sensor 200. This bonding method that forms such an optional structure can also be called "back bonding".

[0061] Alternatively, in some other alternative embodiments, refer to Figure 1B As shown, the second adhesive layer 120 of the adhesive structure 100 can be bonded to the protective layer 214 of the under-display ultrasonic sensor 200. This bonding method, which forms such an optional structure, can also be called "positive bonding".

[0062] It should be understood that the above-mentioned "back-mounted" or "front-mounted" structures can both meet the under-screen bonding requirements of the under-screen ultrasonic sensor 200, and neither will affect the normal use of the under-screen ultrasonic module 1000, effectively ensuring the detection reliability of the under-screen ultrasonic module 1000.

[0063] In this embodiment, the first adhesive layer 110 and the second adhesive layer 120 of the adhesive structure 100 achieve double-sided bonding, and the support layer 130 can provide a certain support for the first adhesive layer 110 and the second adhesive layer 120, thereby improving the structural stability and bonding stability of the adhesive structure 100.

[0064] In this embodiment of the application, the specific thickness of each layer of the adhesive structure 100 is not limited. The specific thickness of the first adhesive layer 110, the second adhesive layer 120 and the support layer 130 can be selected as needed within a specified range.

[0065] For example, the thickness of the first adhesive layer 110 can range from 3µm to 10µm, such as... Figure 1A and Figure 1B As shown, H1 indicates the thickness of the first adhesive layer 110, where 3um ≤ H1 ≤ 10um. Therefore, the thickness H1 of the first adhesive layer 110 can be selected from, but is not limited to, 3.0um, 3.5um, 4.0um, 4.5um, 5.0um, 5.5um, 6.0um, 6.5um, 7.0um, 7.5um, 8.0um, 8.5um, 9.0um, 9.5um, 10.0um, and so on.

[0066] For example, the thickness of the second adhesive layer 120 can range from 5µm to 10µm, such as Figure 1A and Figure 1B As shown, H1 indicates the thickness of the second adhesive layer 120, where 5um ≤ H2 ≤ 10um. Therefore, the thickness H2 of the second adhesive layer 120 can be selected from, but is not limited to, 5.0um, 5.5um, 6.0um, 6.5um, 7.0um, 7.5um, 8.0um, 8.5um, 9.0um, 9.5um, 10.0um, etc.

[0067] In some alternative embodiments, the thickness of the first adhesive layer 110 may be equal to the thickness of the second adhesive layer 120. Such a structure eliminates the need to distinguish between the front and back sides of the adhesive structure 100 during manufacturing, thereby reducing the difficulty of the manufacturing process.

[0068] For example, the thickness of the support layer 130 can range from 17µm to 24µm, such as Figure 1A and Figure 1B As shown, H3 indicates the thickness of the support layer 130, where 17um ≤ H3 ≤ 24um. Therefore, the thickness H3 of the support layer 130 can be selected from, but is not limited to, 17.0um, 17.5um, 18.0um, 18.5um, 19.0um, 19.5um, 20.0um, 20.5um, 21.0um, 21.5um, 22.0um, 22.5um, 23.0um, 23.5um, 24.0um, and so on.

[0069] In one optional combination example, the thickness of the first adhesive layer 110 is 6 μm, the thickness of the support layer 130 is 23 μm, and the thickness of the second adhesive layer 120 is 6 μm. It should be understood that such an example embodiment enables the under-display ultrasonic module 1000 to better adapt to the ultrasonic signal transmission requirements of the screen 300 (also referred to as a carbon fiber screen, for example, a foldable screen) including the carbon fiber reinforcing layer 310. This facilitates acoustic impedance matching between the under-display ultrasonic module and the carbon fiber screen, reduces ultrasonic signal transmission loss, and thus effectively improves the performance and effectiveness of the under-display ultrasonic module in carbon fiber screens, enhancing the reliability and performance of under-display ultrasonic detection.

[0070] In another alternative combination example, the thickness of the first adhesive layer 110 is 6 μm, the thickness of the support layer 130 is 18 μm, and the thickness of the second adhesive layer 120 is 6 μm. It should be understood that this example embodiment allows the under-display ultrasonic module 1000 to better adapt to the ultrasonic signal transmission requirements of the screen 300 (also referred to as a carbon fiber screen, for example, a foldable screen), including the carbon fiber reinforcing layer 310. This facilitates acoustic impedance matching between the under-display ultrasonic module and the carbon fiber screen, reducing ultrasonic signal transmission loss. Therefore, it can effectively and specifically improve the usage effect and performance of the under-display ultrasonic module in the carbon fiber screen, and improve the reliability and performance of under-display ultrasonic detection. Furthermore, compared to the previous combination example, since the thickness of the support layer 130 is reduced in this combination example, the adhesive structure 100 and the under-display ultrasonic module 1000 can also be made thinner and lighter.

[0071] The first adhesive layer 110 in this application embodiment can be made of any material, and is not limited to a single material. For example, in some optional embodiments, the first adhesive layer 110 may include one of PSA (Pressure Sensitive Adhesive), OCA (Optically Clear Adhesive), and PMMA (Poly(methyl methacrylate)) adhesive layers, or the first adhesive layer 110 may be a multilayer adhesive layer in which at least two of PSA, OCA, and PMMA adhesive layers are stacked.

[0072] It should be understood that the first adhesive layer 110 of the aforementioned optional material can effectively meet the bonding reliability with the carbon fiber reinforcing layer 310 of the screen 300. Furthermore, the first adhesive layer 110 of the aforementioned optional material adopts the aforementioned thickness range of 3um to 10um, which can better adapt to the ultrasonic signal transmission requirements of the screen 300 (also referred to as the carbon fiber screen) including the carbon fiber reinforcing layer 310. This is beneficial for achieving acoustic impedance matching between the under-screen ultrasonic module and the carbon fiber screen, reducing the transmission loss of ultrasonic signals. Therefore, it can effectively and specifically improve the usage effect and performance of the under-screen ultrasonic module in the carbon fiber screen, and improve the reliability and performance of under-screen ultrasonic detection.

[0073] It is understandable that the first adhesive layer 110 can be a single layer of the above-mentioned adhesive layers or a multi-layer stack of adhesive layers, which can be set as needed.

[0074] The second adhesive layer 120 in this embodiment can be made of any material, and is not limited to a single material. For example, in some optional embodiments, the second adhesive layer 120 may include one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer, or the second adhesive layer 120 may be a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked.

[0075] It should be understood that the second adhesive layer 120 of the aforementioned optional material can effectively meet the bonding reliability with the carbon fiber reinforcing layer 310 of the screen 300. Furthermore, the second adhesive layer 120 of the aforementioned optional material adopts the aforementioned thickness range of 5um to 10um, which can better adapt to the ultrasonic signal transmission requirements of the screen 300 (also referred to as the carbon fiber screen) including the carbon fiber reinforcing layer 310. This is beneficial for achieving acoustic impedance matching between the under-screen ultrasonic module and the carbon fiber screen, reducing the transmission loss of ultrasonic signals. Therefore, it can effectively and specifically improve the usage effect and performance of the under-screen ultrasonic module in the carbon fiber screen, and improve the reliability and performance of under-screen ultrasonic detection.

[0076] It is understandable that the second adhesive layer 120 can be a single layer of the above-mentioned adhesive layers or a multi-layer stack of adhesive layers, which can be set as needed.

[0077] The first adhesive layer 110 and the second adhesive layer 120 can be of the same type or different types of adhesive layers; there is no single limitation. For example, in one example, the first adhesive layer 110 can be a PSA adhesive layer, and the second adhesive layer 120 can also be a PSA adhesive layer; in another example, the first adhesive layer 110 can be a PSA adhesive layer, and the second adhesive layer 120 can be an OCA adhesive layer; in yet another example, the first adhesive layer 110 can be a PMMA adhesive layer, and the second adhesive layer 120 can be a stack of PSA and OCA adhesive layers; in yet another example, the first adhesive layer 110 can be an OCA adhesive layer, and the second adhesive layer 120 can be a stack of OCA and PMMA adhesive layers; and in yet another example, the first adhesive layer 110 can be a stack of PSA and OCA adhesive layers, and the second adhesive layer 120 can be a stack of OCA and PMMA adhesive layers. Other cases can be selected as needed, and will not be elaborated here.

[0078] In some alternative embodiments, the acoustic impedance of the support layer 130 is greater than that of the first adhesive layer 110 and the second adhesive layer 120.

[0079] Based on this, in this embodiment, a support layer 130 with a higher acoustic impedance than the first adhesive layer 110 and the second adhesive layer 120 is used to better achieve acoustic impedance matching between the under-display ultrasonic module 1000 and the carbon fiber screen, thereby helping to reduce the transmission loss of ultrasonic signals. Therefore, it can more effectively and specifically improve the usage effect and performance of the under-display ultrasonic module in the carbon fiber screen, and improve the reliability and performance of under-display ultrasonic detection.

[0080] It is understood that the specific acoustic impedance of the first adhesive layer 110, the second adhesive layer 120, and the support layer 130 can be selected as needed, and there is no unique limitation in the embodiments of this application.

[0081] The support layer 130 in this embodiment can be made of any material, and there is no single limitation. It can be an organic material support layer or an inorganic material support layer. For example, in some optional embodiments, the support layer 130 can be a metal layer. For example, the metal layer can be at least one of the following metal layers, including but not limited to copper, aluminum, titanium, and iron, or an alloy layer including but not limited to at least two of copper, aluminum, titanium, and iron.

[0082] It should be understood that the adhesive structure 100 made of the metal layer support layer 130 has high structural strength, good bonding stability, good thermal conductivity and heat resistance. Furthermore, due to the large acoustic impedance of metal, the thickness of the metal layer support layer 130, which is reasonably set in the embodiments of this application, can help to better achieve acoustic impedance matching between the under-screen ultrasonic module 1000 and the carbon fiber screen.

[0083] Optionally, taking a copper layer as an example, in some embodiments, the support layer 130 can be a copper foil layer. That is, the adhesive structure 100 can be copper foil adhesive. It should be understood that the adhesive structure 100 (i.e., copper foil adhesive) made of the support layer 130 in the form of a copper foil layer has lower cost, higher structural strength, better bonding stability, and better thermal conductivity and heat resistance, which is beneficial for achieving better acoustic impedance matching between the under-display ultrasonic module 1000 and the carbon fiber screen.

[0084] In this embodiment, the screen 300 is a carbon fiber screen, which can adopt any structure. For example, the screen 300 may include a carbon fiber reinforcing layer 310 and a screen body 320. The carbon fiber reinforcing layer 310 is located below the screen body 320 and can be used as a back panel of the screen 300. The carbon fiber reinforcing layer 310 can reinforce the screen body 320. For example, taking a foldable screen as an example, the laminated materials of its screen body 320 are typically thin and soft. Due to its good strength and bending performance, and its lighter weight compared to reinforcing layers made of other materials, the carbon fiber reinforcing layer 310 can reinforce the thin and soft laminated screen body 320.

[0085] The specific thickness of the carbon fiber reinforcing layer 310 is not limited in the embodiments of this application. For example, in some optional embodiments, the thickness of the carbon fiber reinforcing layer 310 can range from 100 μm to 175 μm.

[0086] It should be understood that the carbon fiber reinforcing layer 310 with an optional thickness range of 100um to 175um can effectively reinforce the screen 300. The under-screen ultrasonic module 1000 in this embodiment of the application, due to its optimized stacked structure, can be effectively applied to under-screen ultrasonic testing of the screen 300 (carbon fiber screen) including the carbon fiber reinforcing layer 310 with an optional thickness range. It is also better adapted to the ultrasonic signal transmission requirements of the carbon fiber screen within this optional thickness range, which is conducive to achieving acoustic impedance matching between the under-screen ultrasonic module and the carbon fiber screen and reducing the transmission loss of ultrasonic signals. Therefore, it effectively and specifically improves the usage effect and performance of the under-screen ultrasonic module in the carbon fiber screen and improves the reliability and performance of under-screen ultrasonic testing.

[0087] For example, such as Figure 1A and Figure 1BAs shown, H indicates the thickness of the carbon fiber reinforcing layer 310, where 100um ≤ H ≤ 175um. Within the above-mentioned selectable thickness range, the thickness H of the carbon fiber reinforcing layer 310 can be selected from, but is not limited to, 100um, 105um, 110um, 115um, 120um, 125um, 130um, 135um, 140um, 145um, 150um, 155um, 160um, 165um, 170um, 175um, etc.

[0088] In some alternative embodiments, the screen 300 in this application embodiment may include one or more available resonant frequencies, for example, the resonant frequency range of the screen 300 is in the range of 5MHz to 20MHz.

[0089] It should be understood that the under-screen ultrasonic module 1000 in this embodiment of the application, due to its optimized stacked structure, can be effectively applied to under-screen ultrasonic testing of the screen 300 (carbon fiber screen) in the resonant frequency range of 5 MHz to 20 MHz, and reduces interference in ultrasonic signal propagation, better adapts to the ultrasonic signal transmission requirements of the carbon fiber screen, facilitates acoustic impedance matching between the under-screen ultrasonic module and the carbon fiber screen, reduces ultrasonic signal transmission loss, and thus effectively improves the usage effect and performance of the under-screen ultrasonic module in the carbon fiber screen, and improves the reliability and performance of under-screen ultrasonic testing.

[0090] For example, within the aforementioned selectable resonant range, the resonant frequency of the screen 300 can be selected from, but is not limited to, 5.0MHz, 5.5MHz, 6.0MHz, 6.5MHz, 7.0MHz, 7.5MHz, 8.0MHz, 8.5MHz, 9.0MHz, 9.5MHz, 10.0MHz, 10.5MHz, 11.0MHz, 11.5MHz, 12.0MHz, 12.5MHz, 13.0MHz, 13.5MHz, 14.0MHz, 14.5MHz, 15.0MHz, 15.5MHz, 16.0MHz, 16.5MHz, 17.0MHz, 17.5MHz, 18.0MHz, 18.5MHz, 19.0MHz, 19.5MHz, 20.0MHz, and so on.

[0091] This application does not specifically limit the specific structure of the screen body 320 of the screen 300. For example, refer to Figure 2AThe diagram illustrates an example of a stacked structure for a screen 300 (carbon fiber screen), which can be understood as a foldable screen. The stacked layers of the screen 320, arranged from closest to furthest from the carbon fiber reinforcing layer 310, may include: a first adhesive layer 3201 (e.g., including but not limited to a PSA adhesive layer), a display panel layer 3202 (e.g., including but not limited to an OLED (Organic Light-Emitting Diode) display panel layer, an LED (Light-Emitting Diode) display panel layer), a second adhesive layer 3203 (e.g., including but not limited to an OCA adhesive layer), a screen cover layer 3204 (e.g., including but not limited to a UTG (Ultra-Thin Glass) cover layer), a third adhesive layer 3205 (e.g., including but not limited to an OCA adhesive layer), and a screen protective film layer 3206 (e.g., including but not limited to tempered glass, soft film, PET (Polyethylene) film). (e.g., terephthalate, polyethylene terephthalate film, hydrogel film, etc.). It is understood that the above examples only illustrate some optional screen stacks; other available stacks can be understood in conjunction with screen structures in related technologies, and will not be elaborated upon here. Other optional carbon fiber screen structures can also be applied to this solution when needed.

[0092] Below, we can use this Figure 2A The stacked structure of screen 300 (carbon fiber screen) in the present application is used as an example to illustrate the advantages of the technical solutions in the embodiments of the present application.

[0093] For example, in Figure 2A In the example, if screen 300 can be understood as a foldable screen, then the carbon fiber screen can be understood as an inward-folding foldable screen. Figure 2A Between the display panel layer 3202 and the screen protective film layer 3206, in addition to adhesive layers (such as the second adhesive layer 3203 and the third adhesive layer 3205), there is also a screen cover layer 3204. This screen cover layer 3204 can protect the display panel layer 3202 and also reduce the plastic deformation after the screen is folded. However, the thickness of this screen cover layer 3204 cannot be too large, otherwise it will affect the bending of the screen 300. The acoustic impedance of the screen cover layer 3204 is significantly greater than that of other adhesive layers and other film layers, so ultrasonic waves will be reflected more significantly when they pass through the two surfaces of the screen cover layer 3204. Similarly, the carbon fiber reinforcement layer 310 of the screen 300 protects the screen body 320 of the screen 300 while providing a certain degree of support for the screen body 320. The carbon fiber reinforcement layer 310 has good strength and toughness, and its acoustic impedance is also significantly greater than that of other adhesive layers and other film layers. Therefore, for Figure 2A The screen 300 described herein can be divided into four resonant cavities 1, 2, 3, and 4. Among them, resonant cavity 4 can be formed by carbon fiber reinforcing layer 310, resonant cavity 3 can be formed by first adhesive layer 3201, display panel layer 3202 and second adhesive layer 3203, resonant cavity 2 can be formed by screen cover layer 3204, and resonant cavity 1 can be formed by third adhesive layer 3205 and screen protective film layer 3206.

[0094] For example, Figure 2B It shows Figure 2A The frequency response of each resonant cavity in the 300-layer stacked screen. For example... Figure 2B As shown, resonant cavity 1 has one resonant frequency within the target frequency range (taking 5MHz to 20MHz as an example), resonant cavity 3 has two resonant frequencies within the target frequency range, and resonant cavity 4 has one resonant frequency within the target frequency range. Resonant cavity 2, due to the smaller thickness of the screen cover layer 3204, has no resonant frequency within the target frequency range. Furthermore, except for resonant cavity 2, which has no resonant frequency within the target frequency range, the resonant frequencies of the other three resonant cavities are close. Moreover, the smaller thickness of the screen cover layer 3204 in resonant cavity 2 has a smaller impact on performance. Therefore, operating in frequency ranges 1 and 2 can achieve good ultrasonic penetration performance.

[0095] In related technologies, combined Figure 3A The diagram illustrates a stacked configuration where an unoptimized under-display ultrasonic module (taking an under-display ultrasonic fingerprint module as an example) is bonded to a carbon fiber reinforcing layer 310 of the screen 300. Because the substrate (e.g., a silicon-based substrate, or silicon base layer) and the bonding layer of the under-display ultrasonic sensor in this under-display ultrasonic module have a significant difference in acoustic impedance, they can be equivalently represented as resonant cavities, namely resonant cavity 5 and resonant cavity 6, respectively. Figure 3B The frequency response of each resonant cavity (i.e., resonant cavity 5 and resonant cavity 6) of the unoptimized under-display ultrasonic module is shown. It is obvious that the frequency point corresponding to the maximum gain in the frequency response of resonant cavity 5 deviates significantly from the preferred ultrasonic penetration frequency range of screen 300 (i.e., frequency range 1 and frequency range 2). Furthermore, the gain in the frequency response of resonant cavity 6 is obviously very low. Therefore, the ultrasonic penetration performance will still be poor after the under-display ultrasonic fingerprint module is attached.

[0096] In conjunction with the technical solutions of the embodiments of this application, the under-display ultrasonic module 1000 provided in the embodiments of this application, taking the under-display ultrasonic fingerprint module as an example, optimizes the ultrasonic penetration performance after the under-display ultrasonic fingerprint module is bonded to the carbon fiber reinforcement layer 310 of the screen 300. Combined with... Figure 4This diagram illustrates a stacking schematic of the optimized under-display ultrasonic module 1000 bonded to the carbon fiber reinforcement layer 310 of the screen 300 in an embodiment of this application (for ease of explanation). Figure 4 The structure located on the side of the substrate 210 opposite to the adhesive structure 100 is omitted. Figure 4 The example under-display ultrasonic module 1000 is a "back-mounted" structure (e.g., it can be combined with...). Figure 1A (Structural understanding), its substrate 210 (e.g., a silicon-based substrate, or silicon base layer) is bonded to the carbon fiber reinforcing layer 310 of the screen 300. Specifically, refer to Figure 4 As shown, in the under-display ultrasonic module 1000 provided in this embodiment, the stacking performance of the adhesive structure 100 is optimized at least. Through the structure of the first adhesive layer 110, the support layer 130, and the second adhesive layer 120, the acoustic impedance of the support layer 130 (which can be a copper foil layer as an example) is relatively high. By optimizing the selection of reasonable thicknesses of the first adhesive layer 110, the support layer 130, and the second adhesive layer 120 (for example, the thickness range of the first adhesive layer 110 is 3um to 10um, the thickness range of the support layer 130 is 17um to 24um, and the thickness range of the second adhesive layer 120 is 5um to 10um), the support layer 130 can be used as an acoustic impedance matching layer. Then, the adhesive structure 100 and the substrate 210 of the under-display ultrasonic sensor 200 can be equivalently used as a resonant cavity 7. The resonant frequency of the resonant cavity 7 can fall well within the preferred frequency range of the screen 300 (i.e., frequency range 1 and frequency range 2), so that the overall ultrasonic penetration performance is better.

[0097] For example, taking one of the combinations mentioned earlier as an example, in the adhesive structure 100 of the under-display ultrasonic module 1000: the thickness of the first adhesive layer 110 is 6µm, the thickness of the support layer 130 is 23µm, and the thickness of the second adhesive layer 120 is 6µm. (Refer to...) Figure 5A The frequency response of the resonant cavity 7 of the optimized stacked structure of an example under-screen ultrasonic module in an embodiment of this application is shown. Combined with... Figure 5A As shown, the resonant frequency of the resonant cavity 7 falls within the preferred frequency range of 1 of the screen 300, resulting in superior overall ultrasonic penetration performance.

[0098] For example, taking another combination example from the previous text, in the bonding structure 100 of the under-display ultrasonic module 1000: the thickness of the first adhesive layer 110 is 6µm, the thickness of the support layer 130 is 18µm, and the thickness of the second adhesive layer 120 is 6µm. (Refer to...) Figure 5B The frequency response of the resonant cavity 7 of the optimized stacked structure of an under-screen ultrasonic module, as shown in another example of an embodiment of this application, is illustrated. Combined with... Figure 5BAs shown, the resonant frequency of the resonant cavity 7 falls within the preferred frequency range of 1 of the screen 300, resulting in superior overall ultrasonic penetration performance.

[0099] Understandably, the above is based on Figures 2A to 5B The illustrative descriptions provided are for illustrative purposes only and are not intended to limit the scope of the embodiments in this application. As can be seen from the above illustrative descriptions, the under-display ultrasonic module 1000 in this application includes an under-display ultrasonic sensor 200 and an adhesive structure 100. The adhesive structure 100 includes a first adhesive layer 110 with a thickness ranging from 3µm to 10µm, a support layer 130 with a thickness ranging from 17µm to 24µm, and a second adhesive layer 120 with a thickness ranging from 5µm to 10µm. The first adhesive layer 110 and the second adhesive layer 120 are located on opposite sides of the support layer 130 in the thickness direction. One side of the second adhesive layer 120 is bonded to the under-display ultrasonic sensor 200, and the other side of the first adhesive layer 110 is bonded to the carbon fiber reinforcement layer of the screen 300. 310 bonding is used to bond the under-screen ultrasonic module 1000 to the underside of the screen 300. By adjusting the thickness of each layer of the bonding structure 100 of the under-screen ultrasonic module 1000 in this embodiment, the ultrasonic signal transmission requirements of the screen (also known as a carbon fiber screen) including the carbon fiber reinforcement layer can be better adapted. This facilitates acoustic impedance matching between the under-screen ultrasonic module 1000 and the carbon fiber screen, reduces ultrasonic signal transmission loss, and thus effectively improves the usage effect and performance of the under-screen ultrasonic module in the carbon fiber screen, improves the reliability and performance of under-screen ultrasonic detection, and realizes the possibility of large-scale application of under-screen ultrasonic detection in electronic devices with carbon fiber screens.

[0100] According to the second aspect of the embodiments of this application, referring to Figure 1A , Figure 1B , Figure 6 As shown, an adhesive structure 100 is provided for bonding an under-display ultrasonic sensor 200 to the underside of a screen 300. The adhesive structure 100 includes a first adhesive layer 110, a support layer 130, and a second adhesive layer 120. The first adhesive layer 110 and the second adhesive layer 120 are located on opposite sides of the support layer 130 in the thickness direction. The second adhesive layer 120 is used to bond with the under-display ultrasonic sensor 200, and the first adhesive layer 110 is used to bond with the carbon fiber reinforcing layer 310 of the screen 300. The thickness of the first adhesive layer 110 ranges from 3µm to 10µm, the thickness of the support layer 130 ranges from 17µm to 24µm, and the thickness of the second adhesive layer 120 ranges from 5µm to 10µm.

[0101] Based on this, since the bonding structure 100 in this embodiment includes a first adhesive layer 110 with a thickness range of 3µm to 10µm, a support layer 130 with a thickness range of 17µm to 24µm, and a second adhesive layer 120 with a thickness range of 5µm to 10µm, the first adhesive layer 110 and the second adhesive layer 120 are respectively located on both sides of the support layer 130 in the thickness direction, and the second adhesive layer 120 on one side is bonded to the under-display ultrasonic sensor 200, and can be bonded to the carbon fiber reinforcing layer 310 of the screen 300 through the first adhesive layer 110 on the other side, the under-display ultrasonic sensor 200 can be bonded. Located below the screen 300, the thickness of each layer of the bonding structure 100 in this embodiment can better adapt to the ultrasonic signal transmission requirements of the screen (also known as a carbon fiber screen) including the carbon fiber reinforcement layer. This facilitates acoustic impedance matching between the under-screen ultrasonic module 1000 and the carbon fiber screen, reduces ultrasonic signal transmission loss, and thus effectively improves the performance and effectiveness of the under-screen ultrasonic module in the carbon fiber screen. It also improves the reliability and performance of under-screen ultrasonic testing, making it possible to apply under-screen ultrasonic testing on a large scale in electronic devices with carbon fiber screens.

[0102] In some optional embodiments, the screen 300 is a foldable screen, the thickness of the carbon fiber reinforcing layer 310 ranges from 100um to 175um, and the resonant frequency range of the screen 300 is from 5MHz to 20MHz.

[0103] In some optional embodiments, the first adhesive layer 110 includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer; or, the first adhesive layer 110 is a multilayer adhesive layer in which at least two of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer are stacked.

[0104] In some optional embodiments, the second adhesive layer 120 includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer; or, the second adhesive layer 120 is a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked.

[0105] In some alternative embodiments, the thickness of the first adhesive layer 110 is equal to the thickness of the second adhesive layer 120.

[0106] In some alternative embodiments, the acoustic impedance of the support layer 130 is greater than the acoustic impedance of the first adhesive layer 110 and the acoustic impedance of the second adhesive layer 120.

[0107] In some alternative embodiments, the support layer 130 is a metal layer.

[0108] In some optional embodiments, the under-display ultrasonic sensor 200 is an under-display ultrasonic fingerprint sensor, and the under-display ultrasonic module 1000 is an under-display ultrasonic fingerprint module.

[0109] In some alternative embodiments, the support layer 130 is a copper foil layer.

[0110] In some optional embodiments, the thickness of the first adhesive layer 110 is 6 μm, the thickness of the support layer 130 is 23 μm, and the thickness of the second adhesive layer 120 is 6 μm; or, the thickness of the first adhesive layer 110 is 6 μm, the thickness of the support layer 130 is 18 μm, and the thickness of the second adhesive layer 120 is 6 μm.

[0111] In some optional embodiments, the under-display ultrasonic sensor 200 includes: a substrate 210, a first electrode 211, an acoustic layer 213, and a second electrode 212; the first electrode 211 is located on the substrate 210, and the acoustic layer 213 is located between the first electrode 211 and the second electrode 212; the second electrode 212 is used to be excited by an excitation signal to excite the acoustic layer 213 to emit ultrasonic signals; the first electrode 211 is used to receive ultrasonic detection signals generated between the second electrode 212 and the first electrode 211 when the returned ultrasonic signals act on the acoustic layer 213.

[0112] In some alternative embodiments, the under-display ultrasonic sensor 200 further includes a protective layer 214 that covers at least a portion of the second electrode 212.

[0113] In some alternative embodiments, the second adhesive layer 120 is bonded to the substrate 210, or the second adhesive layer 120 is bonded to the protective layer 214.

[0114] It should be noted that the various optional embodiments of the bonding structure 100 in the second aspect have been described in detail in the embodiment of the under-screen ultrasonic module 1000 in the first aspect above, and can be understood by referring to the above text, and will not be repeated here.

[0115] According to the third aspect of the embodiments of this application, referring to Figure 7A , Figure 7B As shown, an electronic device 400 is provided, comprising: a screen 300 including a carbon fiber reinforcing layer 310; and an under-screen ultrasonic module 1000 as described in any one of the first aspects; wherein a first adhesive layer 110 of the under-screen ultrasonic module 1000 is bonded to the carbon fiber reinforcing layer 310 so that the under-screen ultrasonic module 1000 is bonded to the underside of the screen 300.

[0116] Optionally, the electronic device 400 can be, but is not limited to, any terminal or non-terminal device, as long as there is a need for under-screen ultrasonic detection. For example, it includes, but is not limited to, mobile phones, tablets, personal computers, etc.

[0117] The screen 300 in this application embodiment can be any screen with a carbon fiber reinforcement layer. For example, in some optional embodiments, the screen 300 can be, but is not limited to, a foldable screen.

[0118] In some optional embodiments, the under-display ultrasonic sensor 200 can be an under-display ultrasonic fingerprint sensor, the under-display ultrasonic module 1000 can be an under-display ultrasonic fingerprint module, and the detected biometric features can include fingerprint features.

[0119] Optionally, such as Figure 7A As shown, it illustrates... Figure 1A The under-display ultrasonic module 1000 with a "back-mounted" structure is bonded to the carbon fiber reinforcement layer 310 of the screen 300 for installation in the electronic device 400. Optionally, as... Figure 7B As shown, it illustrates... Figure 1B The under-display ultrasonic module 1000 with a "positive bonding" structure is bonded to the carbon fiber reinforcement layer 310 of the screen 300 for installation in the electronic device 400.

[0120] The details regarding the under-display ultrasonic module 1000 and the screen 300 have been described in detail in the embodiments of the first aspect above. Further details will not be elaborated here. For specific optional content and related beneficial effects, please refer to the previous text for understanding.

[0121] It is understood that the above descriptions of various aspects of the embodiments of this application are merely optional exemplary descriptions of the technical solutions of the embodiments of this application, and are not intended to limit the embodiments of this application in any way.

[0122] The optional embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present application are not limited thereto. It should be noted that, for the convenience of explaining the embodiments of the present application, the various drawings of the embodiments of the present application are not necessarily drawn to scale, and are only used to facilitate the explanation of the technical solution, and are not intended to limit the embodiments of the present application in any way. Within the scope of the technical concept of the embodiments of the present application, various simple modifications can be made to the technical solutions of the embodiments of the present application. The various technical features included in the different embodiments of the present application can be combined in any suitable manner. In order to avoid unnecessary repetition, the various possible combinations will not be described separately in the embodiments of the present application. However, these simple modifications and combinations should also be regarded as the content disclosed in the embodiments of the present application, and all fall within the protection scope of the embodiments of the present application.

[0123] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". It should be noted that the concepts of "first", "second", etc., mentioned in this application are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies. It should be noted that the modifications "a" and "a plurality" mentioned in this application are illustrative rather than restrictive, and those skilled in the art should understand that, unless explicitly indicated in the context, they should be understood as "one or more".

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An under-screen ultrasonic module, characterized in that, include: Under-display ultrasonic sensor; The adhesive structure includes a first adhesive layer, a support layer, and a second adhesive layer. The first adhesive layer and the second adhesive layer are located on both sides of the support layer in the thickness direction. The second adhesive layer is bonded to the under-display ultrasonic sensor, and the first adhesive layer is used to bond to the carbon fiber reinforcement layer of the screen, so that the under-display ultrasonic module can be bonded to the underside of the screen. The thickness of the first adhesive layer ranges from 3µm to 10µm, the thickness of the support layer ranges from 17µm to 24µm, and the thickness of the second adhesive layer ranges from 5µm to 10µm.

2. The under-screen ultrasonic module according to claim 1, wherein, The screen is a foldable screen, the thickness of the carbon fiber reinforcement layer ranges from 100um to 175um, and the resonant frequency range of the screen is from 5MHz to 20MHz.

3. The under-screen ultrasonic module according to claim 1, wherein, The under-screen ultrasonic module satisfies at least one of the following conditions: The first adhesive layer includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer, or the first adhesive layer is a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked. The second adhesive layer includes one of a PSA adhesive layer, an OCA adhesive layer, and a PMMA adhesive layer, or the second adhesive layer is a multilayer adhesive layer in which at least two of the PSA adhesive layer, OCA adhesive layer, and PMMA adhesive layer are stacked. The thickness of the first adhesive layer is equal to the thickness of the second adhesive layer; The acoustic impedance of the support layer is greater than the acoustic impedance of the first adhesive layer and the acoustic impedance of the second adhesive layer. The support layer is a metal layer; The under-display ultrasonic sensor is an under-display ultrasonic fingerprint sensor, and the under-display ultrasonic module is an under-display ultrasonic fingerprint module.

4. The under-screen ultrasonic module according to claim 3, wherein, The support layer is a copper foil layer.

5. The under-screen ultrasonic module according to any one of claims 1-4, characterized in that, The thickness of the first adhesive layer is 6 μm, the thickness of the support layer is 23 μm, and the thickness of the second adhesive layer is 6 μm. or, The thickness of the first adhesive layer is 6 μm, the thickness of the support layer is 18 μm, and the thickness of the second adhesive layer is 6 μm.

6. The under-screen ultrasonic module according to any one of claims 1-4, wherein, The under-display ultrasonic sensor includes: a substrate, a first electrode, an acoustic layer, and a second electrode; The first electrode is located on the substrate, and the acoustic layer is located between the first electrode and the second electrode; The second electrode is used to be excited by an excitation signal to induce the acoustic layer to emit ultrasonic signals; The first electrode is used to receive the ultrasonic detection signal generated between the second electrode and the first electrode when the returned ultrasonic signal acts on the acoustic layer.

7. The under-screen ultrasonic module according to claim 6, wherein, The under-display ultrasonic sensor also includes a protective layer that covers at least a portion of the second electrode.

8. The under-screen ultrasonic module according to claim 7, wherein, The second adhesive layer is bonded to the substrate, or the second adhesive layer is bonded to the protective layer.

9. An adhesive structure, characterized by The adhesive structure is used to bond the under-display ultrasonic sensor to the underside of the screen. The adhesive structure includes: a first adhesive layer, a support layer, and a second adhesive layer. The first adhesive layer and the second adhesive layer are located on both sides of the support layer in the thickness direction. The second adhesive layer is used to bond with the under-display ultrasonic sensor, and the first adhesive layer is used to bond with the carbon fiber reinforcement layer of the screen. The thickness of the first adhesive layer ranges from 3µm to 10µm, the thickness of the support layer ranges from 17µm to 24µm, and the thickness of the second adhesive layer ranges from 5µm to 10µm.

10. An electronic device, comprising: include: The screen, including a carbon fiber reinforcement layer; and, The under-screen ultrasonic module as described in any one of claims 1-8; The first adhesive layer of the under-screen ultrasonic module is bonded to the carbon fiber reinforcing layer so that the under-screen ultrasonic module is bonded to the underside of the screen.

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