Composite functional capacitive sensor device

Abstract

The present application relates to a composite function capacitive sensor device, comprising a first printed circuit board, a display, a sensor, a micro control unit, a sensor driving integrated circuit, a second printed circuit board and a display circuit. The display is used to display real-time information; the sensor is used to sense the fingerprint image, writing track and / or electronic signature of the user to generate a sensing signal; the micro control unit is used to process the data from the sensor and the display; the sensor driving integrated circuit is used to drive the sensor and process the sensing signal; the second printed circuit board is used to transmit the sensing signal and distribute power; and the display circuit provides power and sensing signal for the display, and sends the data processed by the micro control unit to the display circuit, and then displays the real-time recognition result on the display.

Description

Technical Field

[0001] This invention relates to a composite functional capacitive sensing device, and more specifically to a composite functional capacitive sensing device in which the transparency of a transparent glass fingerprint sensor is integrated with the display, and can provide relevant information in a timely manner. Background Technology

[0002] Modern electronic signature pads integrate high-precision touch and pressure-sensitive technology, accurately capturing the thickness and pressure of the user's strokes to realistically reproduce the handwriting effect. Many electronic signature pads further incorporate transparent glass display technology (such as OLED), allowing signatures to be displayed instantly on the screen and integrated with other devices (such as touchscreens) for a more intuitive user experience. In addition, electronic signature pads support multiple connectivity methods such as Bluetooth and Wi-Fi, and combine with cloud technology to achieve instant storage and sharing of signed documents. As an important tool for paperless offices, electronic signature pads play a significant role in improving office efficiency and data security. With continuous technological advancements and expanding application scenarios, their market potential is enormous, and they are expected to occupy an increasingly important position in the digital economy.

[0003] Meanwhile, fingerprint sensors in biometric technology are also developing rapidly, providing a secure and reliable solution for identity verification. Optical fingerprint sensors capture fingerprint images using the principle of light reflection or penetration, and are mainly used in the under-screen fingerprint unlocking function of smartphones. Capacitive fingerprint sensors capture fingerprints by measuring the current or voltage changes between the skin and the sensor, and are widely used in smartphones, laptops, and identity verification devices. Ultrasonic fingerprint sensors capture fingerprint details using ultrasonic beams, offering higher accuracy and security, and are particularly suitable for fingerprint recognition in wet hands or complex scenarios. In contrast, thermal fingerprint sensors scan by detecting temperature differences on the fingerprint surface; although the technology is simple, its accuracy is lower than other methods. Fingerprint sensors are developing towards higher precision, integration, and multi-functionality, and are being widely applied in many fields. With continuous technological breakthroughs and increasing market demand, the future development potential of fingerprint sensors is enormous, especially in the deeper and more diversified applications in smart devices, security, and fintech.

[0004] However, current electronic signature pads cannot capture fingerprint images, and fingerprint sensors have not yet been integrated into these products. Furthermore, mobile phone fingerprint functionality is limited to single-user use, and the fingerprint sensing area is too small, making it ineligible for FBI-IQS certification and difficult to integrate with electronic signature functions. These limitations reduce the comprehensiveness of functionality and ease of use in practical applications. Therefore, integrating electronic signature pads with fingerprint sensor technology has become a crucial requirement, not only enhancing the versatility and practicality of devices but also better meeting market expectations for efficient and secure digital solutions. In the future, the combined application of these technologies will continue to play a vital role in paperless office environments, data security, and smart devices.

[0005] In summary, in order to overcome the aforementioned shortcomings, the inventors of this case have devoted considerable research and development energy and spirit to continuous breakthroughs and innovations in this field, hoping to solve the deficiencies of conventional methods with novel technical means, thereby bringing better products to society and promoting industrial development. Summary of the Invention

[0006] To address the aforementioned issues, this invention provides an electronic signature device with capacitive sensing capabilities. The device features a highly transparent glass fingerprint sensor that integrates seamlessly with the display, providing real-time information and combining with electronic signature functionality for a unified design. This design significantly reduces the space requirements of the user organization, avoiding the need to place multiple single-function devices on a desktop, making it ideal for applications such as POS machines, banking services, and identity verification. Furthermore, the glass fingerprint sensor can operate independently. In fingerprint sampling mode, the OLED display prompts the user for the correct pressing method and instantly displays the fingerprint image; in electronic signature mode, the OLED displays the signature text instantly. When fingerprint or signature modes are not in use, the OLED display can also be used to play introductory videos, further enhancing the device's functionality and application flexibility.

[0007] To achieve the aforementioned objectives, this invention discloses a composite functional capacitive sensing device comprising: a first printed circuit board, a display, a sensor, a microcontroller unit (MCU), a sensor driver IC, a second printed circuit board, and a display circuit. First, the display, positioned above the first printed circuit board, has high transparency and is used to display real-time information. Second, the sensor, positioned above the display, is used to sense a user's fingerprint image, writing trajectory, and / or electronic signature to generate multiple sensing signals. Third, the MCU is positioned below the first printed circuit board and electrically connected to the display and the sensor via the first printed circuit board, used to process data from the sensor and the display, and control the operation of fingerprint recognition, writing trajectory identification, and / or electronic signature. Finally, the sensor driver IC, positioned below the first printed circuit board, is electrically connected to the sensor via a data line, used to drive the sensor and process the multiple sensing signals, and transmit the processed multiple sensing signals to the MCU via a data channel. Furthermore, the second printed circuit board is disposed below the microcontroller unit and the sensor driver integrated circuit, and is electrically connected to the sensor and the microcontroller unit via the data lines or solder points to transmit the multiple sensor signals and distribute power. In addition, the display circuit is disposed below the second printed circuit board and is electrically connected to the display. The display circuit provides power and the multiple sensor signals to the display, and sends the data processed by the microcontroller unit to the display circuit. The display circuit then displays the real-time fingerprint recognition result, writing trajectory, electronic signature sample, and other relevant information on the display.

[0008] In the composite functional capacitive sensing device of the present invention, the sensor comprises: a substrate; a signal processing circuit layer disposed above the substrate for extracting a fingerprint feature and / or a handwriting feature; an interconnect layer electrically coupled to the signal processing circuit layer and used to transmit a capacitance signal; an electrode array layer electrically coupled to the interconnect layer and including a plurality of electrodes arranged in a plurality of matrix arrays for sensing a capacitance value change function of a contact object relative to the electrode array layer, thereby obtaining a fingerprint, writing trajectory (handwriting or text), and / or an electronic signature; and a dielectric layer electrically coupled to the electrode array layer and used to isolate the electrodes, prevent short circuits, and enhance the capacitance effect.

[0009] The composite functional capacitive sensing device of the present invention further includes a flexible printed circuit board connector (FPC connector) disposed below the second printed circuit board, for electrically connecting the composite functional capacitive sensing device with an external device to perform data transmission or exchange of control commands.

[0010] In the composite functional capacitive sensing device of the present invention, the sensor driver integrated circuit amplifies and processes the multiple sensing signals sensed by the sensor, and transmits the processed signals to the microcontroller unit for analysis.

[0011] In the composite functional capacitive sensing device of the present invention, the sensor includes a multi-functional sensing unit capable of simultaneously performing fingerprint recognition, writing trajectory identification, and / or electronic signature sensing, and transmitting the corresponding sensing signals to the microcontroller unit for analysis and processing.

[0012] In the composite functional capacitive sensing device of the present invention, the multifunctional sensing unit further includes a fingerprint recognition element for sensing the fingerprint image of the user and generating a corresponding fingerprint recognition signal, and the microcontroller unit is used to process the fingerprint recognition signal to perform fingerprint recognition operation.

[0013] In the composite functional capacitive sensing device of the present invention, the multifunctional sensing unit further includes a pressure sensing element for sensing the pressure applied by the user to the sensor and generating a corresponding pressure sensing signal, and the microcontroller unit is used to process the pressure sensing signal to adjust the pressure sensitivity and pen pressure sensing.

[0014] In the composite functional capacitive sensing device of the present invention, a hard coating is further included, which covers the sensor. The hard coating is made of a transparent and wear-resistant material selected from polycarbonate, silicon oxide, silicon oxynitride, ultraviolet-curable polymer, fluorinated polymer, diamond-like carbon (DLC), polyurethane, and combinations thereof.

[0015] In the composite functional capacitive sensing device of the present invention, a layered electrostatic discharge protection layer is further included, which is disposed between the hard coating and the sensor and connected to the signal pin or power pin of the sensor to prevent damage from electrostatic discharge. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 1 of the present invention.

[0017] Figure 2 This is a schematic cross-sectional view of the sensor in the composite functional capacitive sensing device of Embodiment 1 of the present invention.

[0018] Figure 3 This is a schematic block diagram of the sensor and sensor driver integrated circuit of the composite functional capacitive sensing device according to Embodiment 1 of the present invention.

[0019] Figure 4 This shows a structural diagram of the sensing matrix of the sensor in Embodiment 1 of the present invention.

[0020] Figure 5 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 2 of the present invention.

[0021] Figure 6 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 3 of the present invention.

[0022] Figure 7 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 4 of the present invention.

[0023] Figure 8 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 5 of the present invention.

[0024] Figure 9 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 6 of the present invention.

[0025] Wherein: 1: Composite functional capacitive sensing device; 10: First printed circuit board; 11: Microcontroller unit; 12: Sensor driver integrated circuit; 121: Internal circuit; 1221: Clock generator; 1222: Receiving sensing unit; 1223: Transmitting sensing unit; 1224: Signal buffer unit; 1225: Signal transmission element; 20: Display; 30: Sensor; 31: Substrate; 32: Signal processing circuit layer; 33: Interconnect layer; 34: Electrode array layer; 341: Electrode; 35: Dielectric layer; 40: Second printed circuit board; 41: Display circuit; 42: Flexible printed circuit board connector; 43: USB connector; 50: Hard coating; 60: Electrostatic discharge protection layer; 70: Optical transparent adhesive; 71: External frame. Detailed Implementation

[0026] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the invention are now described in detail with reference to the accompanying drawings. The detailed description and technical content of the present invention are illustrated below in conjunction with the accompanying drawings; however, the accompanying drawings are provided for reference and illustration only and are not intended to limit the scope of the invention.

[0027] In addition, it should be understood that when a component is indicated as "connected" or "electrically coupled" to another component, it can be directly connected or coupled to the other component, or there can be an intermediate component.

[0028] Please see Figure 1 , Figure 1 This is a cross-sectional view of the composite functional capacitive sensing device of Embodiment 1 of the present invention.

[0029] like Figures 1 to 2 As shown, the present invention describes a composite functional capacitive sensing device 1 comprising: a first printed circuit board 10, a display 20, a sensor 30, a microcontroller unit 11, a sensor driver integrated circuit 12, a second printed circuit board 40, and a display circuit 41.

[0030] First, the display 20 is disposed above the first printed circuit board 10, has high transparency, and is used to display real-time information. The display 20 is an OLED display, an LCD display, or a touch display, used to display various real-time information and receive user operation commands.

[0031] Secondly, the sensor 30 is disposed above the display 20 and is used to sense a user's fingerprint image, writing trajectory, and / or electronic signature to generate multiple sensing signals. The sensor 30 employs multi-touch technology, capable of simultaneously sensing multiple contact points and accurately identifying them based on the multi-touch signals. The sensor 30 includes a multi-functional sensing unit capable of simultaneously sensing fingerprint recognition, writing trajectory recognition, and / or electronic signatures, and transmitting the corresponding sensing signals to the microcontroller unit for analysis and processing. In one embodiment, the multi-functional sensing unit further includes a fingerprint recognition element for sensing the user's fingerprint image and generating a corresponding fingerprint recognition signal, and the microcontroller unit 11 is used to process the fingerprint recognition signal to perform fingerprint recognition operations. In another embodiment, the multi-functional sensing unit further includes a pressure sensing element for sensing the pressure applied by the user to the sensor and generating a corresponding pressure sensing signal, and the microcontroller unit is used to process the pressure sensing signal to adjust pressure sensitivity and pen pressure sensing.

[0032] Furthermore, the microcontroller unit 11 is disposed below the first printed circuit board 10, and is electrically connected to the display 20 and the sensor 30 through the first printed circuit board 10. It processes data from the sensor 30 and the display 20, and controls fingerprint recognition, writing trajectory recognition, and / or electronic signature operations. The data processing performed by the microcontroller unit 11 includes fingerprint recognition algorithms, writing trajectory recognition algorithms, and / or electronic signature recognition algorithms.

[0033] Next, the sensor driver integrated circuit 12 is disposed below the first printed circuit board 10 and electrically connected to the sensor 30 via a data line. It drives the sensor 30 and processes the plurality of sensing signals, transmitting the processed signals to the microcontroller unit 11 via a data channel. The sensor driver integrated circuit 12 amplifies and processes the plurality of sensing signals sensed by the sensor 30 and transmits the processed signals to the microcontroller unit 11 for analysis.

[0034] Furthermore, the second printed circuit board 40 is disposed below the microcontroller unit 11 and the sensor driver integrated circuit 12, and is electrically connected to the sensor 30 and the microcontroller unit 11 through the data line or solder point to perform the transmission of the multiple sensor signals and power distribution.

[0035] In addition, the display circuit 41 is disposed below the second printed circuit board 40 and electrically connected to the display 20. The display circuit 41 provides power and the multiple sensor signals to the display 20, and sends the data processed by the microcontroller unit 11 to the display circuit 41. The display circuit 41 then displays the real-time fingerprint recognition result, writing trajectory, electronic signature sample and other relevant information on the display 20.

[0036] Please see Figure 2 , Figure 2 This is a schematic cross-sectional view of the sensor in the composite functional capacitive sensing device of Embodiment 1 of the present invention.

[0037] like Figure 2 As shown, the sensor 30 includes: a substrate 31, a signal processing circuit layer 32, an interconnect layer 33, an electrode array layer 34, and a dielectric layer 35. The signal processing circuit layer 32 is disposed above the substrate 31 and is used to extract a fingerprint feature and / or a handwriting feature. The interconnect layer 33 is electrically coupled to the signal processing circuit layer 32 and is used to transmit a capacitance signal. Furthermore, the electrode array layer 34 is electrically coupled to the interconnect layer 33 and includes a plurality of electrodes 341 arranged in a plurality of matrix arrays for sensing a capacitance change function of a contact object relative to the electrode array layer 34, thereby obtaining a fingerprint, writing trajectory (handwriting or text), and / or an electronic signature. The contact object is at least one selected from a biological individual's finger, palm, toe, electronic pen, writing instrument, and combinations thereof. Moreover, the dielectric layer 35 is electrically coupled to the electrode array layer 34 and is used to isolate the electrodes, prevent short circuits, and enhance the capacitance effect.

[0038] Please see Figure 3 , Figure 3This is a schematic block diagram of the sensor and sensor driver integrated circuit of the composite functional capacitive sensing device according to Embodiment 1 of the present invention.

[0039] like Figure 3 As shown, an internal circuit 121 of the sensor driver integrated circuit 12 includes a clock generator 1221, a receiving sensing unit 1222, a transmitting sensing unit 1223, a signal buffer unit 1224, and a signal transmission element 1225. With the help of the clock signal Sck generated by the clock generator 1221, the receiving sensing unit 1222, the transmitting sensing unit 1223, the signal buffer unit 1224, and the signal transmission element 1225 perform regular sensing steps. During the sensing steps, in response to an activation command provided by the user, the transmitting sensing unit 1223 is configured to receive the clock signal Sck and generate an initial sensing signal Si and a control signal Sc, and transmits the initial sensing signal Si to the contact object through the signal buffer unit 1224 and the signal transmission element 1225. The transmission sensing unit 1223 is configured to send the initial sensing signal Si or the control signal Sc to the receiving sensing unit 1222 to synchronize the reception of the plurality of sensing signals and the elements in the receiving sensing unit 1222, such as switches.

[0040] Furthermore, the signal buffer unit 1224 is configured to buffer the initial sensing signal Si and generate a buffered sensing signal Sb. The signal buffer unit 1224 can also convert the voltage or current level of the initial sensing signal Si to another signal level to provide the driving capability required for the sensing step. The signal buffer unit 1224 includes at least one of a current amplification circuit and a level shifter, configured to generate the buffered sensing signal Sb in response to the initial sensing signal Si.

[0041] The signal transmission element 1225 is configured to generate a transmission sensing signal St in response to the buffer sensing signal Sb and transmit it to the contact. The signal transmission element 1225 can transmit the buffer sensing signal Sb through the contact or in a contactless manner. In touch mode, the signal transmission element 1225 includes a conductive layer and / or a frame, and the buffer sensing signal Sb is transmitted through the conductive layer and / or the frame as the transmission sensing signal St. During a touch event, the contact approaches or contacts the electrode array layer 34 and receives the transmission sensing signal St. A capacitance Cfinger is thus generated between the contact and the plurality of electrodes 341. The plurality of electrodes 341 can generate a receiving sensing signal Sr, which is generated by the transmission sensing signal St transmitted to the contact and the capacitance Cfinger in response to the touch event.

[0042] The receiving sensing control unit 1222 is configured to receive the sensing signal Sr and generate a digital sensing signal Sd, which represents the sensing results provided by the plurality of electrodes 341 in response to a touch event. The digital sensing signal Sd can be transmitted to the microcontroller unit 11, where each digital sensing signal Sd detected by different parts of the contact object by different of the plurality of electrodes 341 is processed to form a processing signal Sp representing the contact object.

[0043] In one embodiment, when the contact object is a finger, the signal processing circuit layer 32 reads a fingerprint image of a fingerprint pattern and transmits the information to the sensor driver integrated circuit 12. The sensor driver integrated circuit 12 converts a first capacitance value C1(x,y) collected by the electrode array layer 34 into a corresponding primitive value I(x,y) through a grayscale mapping function f. The grayscale mapping function f adopts a logarithmic function form and satisfies the following relationship function (1):

[0044] I(x,y)=f(C1(x,y)) ----------(1);

[0045] Where C1(x,y) represents the first capacitance value measured by the electrode array layer at position (x,y);

[0046] I(x,y) refers to the gray value of the primitive at position (x, y), representing the brightness of the image at (x, y).

[0047] Furthermore, the fingerprint feature extraction includes extracting the ridge bifurcation points and termination points in the fingerprint image. The fingerprint image is a grayscale image generated based on the change of a first capacitance value. The area with a larger first capacitance value corresponds to the ridge of the fingerprint, and the area with a smaller first capacitance value corresponds to the valley of the fingerprint.

[0048] Each electrode 341 in the electrode array layer 34 includes a microcapacitor used to detect the ridges (contact portions) and valleys (non-contact portions) of a fingerprint. When a finger touches the electrode array layer 34, the conductivity of the fingerprint ridges changes the charging level of the microcapacitor, while the fingerprint valleys, lacking contact, generate different capacitance values. These capacitance values ​​are converted into electronic signals, generating a complete fingerprint image.

[0049] In another embodiment, the signal processing circuit layer 32 reads a stroke image from the pen tip of the writing instrument and transmits the information to the sensor driver integrated circuit 12. The sensor driver integrated circuit 12 reconstructs the stroke trajectory based on a second capacitance value C2(x,y), a writing speed v(x,y,t), and a writing pressure p(x,y,t) collected by the electrode array layer 34, through a function g that combines speed, pressure, and capacitance changes. The function g adopts a Kalman filter model and satisfies the following relationship function (2):

[0050] P(x,y,t)=g(C2(x,y,t),v(x,y,t),p(x,y,t)) ----------(2)

[0051] Where C2(x,y,t) represents the second capacitance value measured by the electrode array layer at time t and position (x, y); v(x, y, t) represents the writing speed of the pen tip at time t and position (x, y); and p(x, y, t) represents the writing pressure applied by the pen tip at time t and position (x, y). The feature extraction of the handwriting trajectory includes analyzing the pressure, speed, direction, or turning points of the writing strokes to generate a signature verification handwriting trajectory; the reconstruction of the handwriting trajectory involves generating a path map based on changes in a second capacitance value, and analogizing the thickness, pressure, and / or speed of the writing strokes based on the changes in the second capacitance value.

[0052] Please see Figure 4 , Figure 4 This shows a structural diagram of the sensing matrix of the sensor in Embodiment 1 of the present invention.

[0053] like Figure 4 As shown, Figure 4 In the diagram, NSEL1, NSEL2, NSEL3, NSEL4, FSEL1, FSEL2, FSEL3, and FSEL4 represent the straight-line selection signal, controlling which straight line (1~32) is selected. Black and red dots indicate the control switches corresponding to the control lines. A red box indicates a permanent physical connection on the panel. RX1 to RX8 represent the sensor signal receiving channel; the sensor driver integrated circuit 12 is connected to this receiving channel to record signal changes. By changing the values ​​of the control signals NSEL1, NSEL2, NSEL3, NSEL4, FSEL1, FSEL2, FSEL3, and FSEL4, both general fingerprint reading mode and stylus mode are achieved.

[0054] Figure 4This describes the image reading operation logic in pen mode, specifically the data processing method used when the panel enters a fast mode to handle image data input by the pen. The fast mode is designed to improve image reading speed, especially during rapid writing or signing. When the panel enters fast mode, the image reading from the receiving channel undergoes "partial selection" to accelerate data processing. Specifically, partial selection involves reading image data only every 4 or 5 columns; that is, not every column of image data is read, but some columns are skipped to reduce the total amount of data.

[0055] Secondly, while a complete image dataset would normally contain information from all columns, in the fast mode, the controller processes only a portion of the data—1 / 4 or 1 / 5 of the image—significantly reducing the amount of data read. When the data volume is reduced by 1 / 4 or 1 / 5, the total reading time for each image decreases accordingly, assuming the controller's reading speed remains constant. Therefore, the controller can process the entire image faster, thereby improving the overall system's responsiveness. In pen mode, to accelerate image reading, the composite-functional capacitive sensing chip 1 selects only a portion of the columns (every 4 or 5 columns) instead of reading the entire image. This reduces the amount of data processed, shortening image reading and processing time, resulting in faster response times. This is particularly suitable for scenarios requiring high-speed input, such as signing or rapid writing.

[0056] Please see Figure 5 , Figure 5 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 2 of the present invention.

[0057] like Figure 5 As shown, Embodiment 2 of the present invention is largely the same as Embodiment 1, except that: the composite functional capacitive sensing device 1 of Embodiment 2 further includes a flexible printed circuit board connector (FPC connector) 42, which is disposed below the second printed circuit board 40, for electrically connecting the composite functional capacitive sensing device 1 to an external device for data transmission or exchange of control commands.

[0058] Please see Figure 6 , Figure 6 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 3 of the present invention.

[0059] like Figure 6As shown, Embodiment 3 of the present invention is largely the same as Embodiment 1, except that: the composite functional capacitive sensing device 1 of Embodiment 3 further includes a hard coating 50 covering the sensor 30. The hard coating 50 is made of at least one transparent and wear-resistant material selected from polycarbonate, silicon oxide, silicon oxynitride, ultraviolet-curable polymer, fluorinated polymer, diamond-like carbon (DLC), polyurethane, and combinations thereof.

[0060] Please see Figure 7 , Figure 7 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 4 of the present invention.

[0061] like Figure 7 As shown, Embodiment 4 of the present invention is largely the same as Embodiment 1, except that the composite functional capacitive sensing device 1 of Embodiment 3 further includes a layered electrostatic discharge protection layer (ESD Protection Layer) 60, disposed between the hard coating layer and the sensor, and connected to the signal pin or power pin of the sensor to prevent damage from electrostatic discharge. The ESD Protection Layer 60 is used to prevent electrostatic discharge (ESD) from damaging electronic devices or components. ESD is a phenomenon that rapidly releases electrostatic energy, which can have a destructive effect on sensitive electronic components, leading to component failure or performance degradation. Therefore, the ESD Protection Layer 60 is widely used in various electronic products and systems. The ESD Protection Layer 60 is composed of at least one material selected from conductive polymers, metal oxides, carbon-based materials, coating materials, and combinations thereof; wherein the conductive polymer includes polyaniline (PANI) or polyacetylene; the metal oxide includes indium tin oxide (ITO); the carbon-based material includes graphene or carbon nanotubes; and the coating material includes antistatic coatings or polyester films.

[0062] Please see Figure 8 , Figure 8 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 5 of the present invention.

[0063] like Figure 8 As shown, Embodiment 5 of the present invention is largely the same as Embodiment 1, except that the composite functional capacitive sensing device 1 of Embodiment 3 further includes at least one USB connector 43, disposed below the first printed circuit board or the second printed circuit board, for use as a hardware interface for transmitting data and power. It is widely used for connections between electronic devices. The USB connector 43 enables bidirectional data transmission between devices, such as data exchange between a computer and a tablet.

[0064] Please see Figure 9 , Figure 9 This is a schematic diagram of the composite functional capacitive sensing device of Embodiment 6 of the present invention.

[0065] like Figure 9 As shown, Embodiment 6 of the present invention is largely the same as Embodiment 1, except that the composite functional capacitive sensing device 1 of Embodiment 6 further includes an optically clear adhesive 70 and an outer frame (Bezel) 71. The optically clear adhesive 70 is a transparent adhesive material used in optical applications. Its main function is to bond different layers (such as glass, display screen, fingerprint sensor, etc.) with high transparency while maintaining optical performance. The high transparency of the optically clear adhesive reduces light reflection and scattering, enhances light penetration, and ensures that the fingerprint sensor can accurately capture fingerprint images. Secondly, by using the optically clear adhesive 70, interference caused by interface reflection or bubbles can be effectively reduced, thereby improving recognition accuracy. Furthermore, the optically clear adhesive 70 not only stably bonds the fingerprint sensor to other layers but also provides a certain degree of shock resistance, dustproofing, and waterproofing protection. The high-quality optically clear adhesive 70 has anti-yellowing capabilities during long-term use, maintaining the optical and aesthetic performance of the fingerprint device.

[0066] like Figure 9 As shown, the outer frame 71 is a bezel surrounding the hard-coated display screen 50. The outer frame 71 serves as a protective structure for the display 20 or the sensor 30, preventing damage during use or accidental impact. The outer frame 71 helps secure the components in the composite-functional capacitive sensing device 1, ensuring stability and durability. In one embodiment, the outer frame 71 also integrates additional functions such as buttons, sensors, LED indicators, or speaker holes.

[0067] In summary, the composite-functional capacitive sensing device 1 of this invention provides instant and high-precision fingerprint recognition, which can be used for identity authentication and security protection. Writing trajectory and electronic signature sensing support the recording and recognition of handwriting, suitable for applications such as electronic signatures and data input, enhancing the interactive experience. Pressure sensing can detect applied pressure, further improving the sensitivity and accuracy of handwriting or touch control. Secondly, the combination of the microcontroller unit 11 and the sensor driver integrated circuit 12 enables instant processing of sensing signals (such as fingerprint feature extraction, handwriting recognition, etc.) and direct display of the results on the display, providing a seamless interactive experience. Thirdly, the display has high transparency, enabling clear display of instant information, such as fingerprint recognition results or handwriting. Furthermore, the wear-resistant and transparent hard coating 50 enhances the durability of the device, effectively protecting the sensor from scratches and damage. Finally, the electrostatic protective layer 60 provides electrostatic discharge protection, effectively preventing damage to the sensor from static electricity, enhancing system stability and lifespan. Furthermore, the design of the first printed circuit board 10, the second printed circuit board 40, and the flexible printed circuit board connector 42 enables efficient integration of functional modules and supports data exchange and control command interaction with external devices.

Claims

1. A composite functional capacitive sensing device, characterized in that, include: The first printed circuit board; A display, disposed above the first printed circuit board, has high transparency and is used to display real-time information; A sensor, positioned above the display, is used to sense a user's fingerprint image, writing trajectory, and / or electronic signature to generate multiple sensing signals. A microcontroller unit (MCU) is disposed below the first printed circuit board and electrically connected to the display and the sensor through the first printed circuit board. It is used to process data from the sensor and the display and control the operation of fingerprint recognition, writing trajectory recognition and / or electronic signature. A sensor driver IC is disposed below the first printed circuit board and electrically connected to the sensor via a data line. It is used to drive the sensor and process the multiple sensing signals, and transmit the processed multiple sensing signals to the microcontroller through a data channel. A second printed circuit board is disposed below the microcontroller unit and the sensor driver integrated circuit, and is electrically connected to the sensor and the microcontroller unit through the data line or solder point to transmit the multiple sensor signals and distribute power. as well as A display circuit is disposed below the second printed circuit board and electrically connected to the display. The display circuit provides power and multiple sensor signals to the display and sends the data processed by the microcontroller to the display circuit. The display circuit then displays the real-time fingerprint recognition result, writing trajectory, electronic signature sample and other relevant information on the display.

2. The composite functional capacitive sensing device according to claim 1, characterized in that, The sensor includes: One substrate; A signal processing circuit layer is disposed above the substrate for extracting a fingerprint feature and / or a handwriting feature; An interconnect layer electrically coupled to the signal processing circuit layer and used to transmit a capacitor signal; An electrode array layer electrically coupled to the interconnect layer and comprising multiple electrodes arranged in a plurality of matrix arrays for sensing a capacitance change function of a contact object relative to the electrode array layer, thereby obtaining fingerprints, writing traces (handwriting or text), and / or electronic signatures; and A dielectric layer electrically coupled to the electrode array layer and used to isolate the electrodes, prevent short circuits, and enhance the capacitance effect.

3. The composite functional capacitive sensing device according to claim 1, characterized in that, It also includes a flexible printed circuit board connector (FPC connector) disposed below the second printed circuit board, for electrically connecting the composite functional capacitive sensing device to an external device for data transmission or control command exchange.

4. The composite functional capacitive sensing device according to claim 1, characterized in that, The sensor driver integrated circuit amplifies and processes the multiple sensing signals detected by the sensor, and transmits the processed signals to the microcontroller unit for analysis.

5. The composite functional capacitive sensing device according to claim 1, characterized in that, The sensor includes a multi-functional sensing unit that can simultaneously perform fingerprint recognition, writing trajectory identification, and / or electronic signature sensing, and transmit the corresponding sensing signals to the microcontroller unit for analysis and processing.

6. The composite functional capacitive sensing device according to claim 5, characterized in that, The multi-functional sensing unit also includes a fingerprint recognition element for sensing the user's fingerprint image and generating a corresponding fingerprint recognition signal, and the microcontroller unit is used to process the fingerprint recognition signal to perform fingerprint recognition operation.

7. The composite functional capacitive sensing device according to claim 5, characterized in that, The multi-functional sensing unit also includes a pressure sensing element for sensing the pressure applied by the user to the sensor and generating a corresponding pressure sensing signal. The microcontroller unit is used to process the pressure sensing signal to adjust the pressure sensitivity and pen pressure sensing.

8. The composite functional capacitive sensing device according to claim 1, characterized in that, It also includes a hard coating covering the sensor, the hard coating being a transparent and abrasion-resistant material selected from polycarbonate, silicon oxide, silicon oxynitride, UV-curable polymer, fluorinated polymer, diamond-like carbon (DLC), polyurethane, and combinations thereof.

9. The composite functional capacitive sensing device according to claim 8, characterized in that, It also includes a single-layer electrostatic discharge protection layer (ESD Protection Layer) disposed between the hard coating and the sensor, and connected to the signal pin or power pin of the sensor to prevent damage from electrostatic discharge.

10. The composite functional capacitive sensing device according to claim 1, characterized in that, It also includes at least one USB connector, disposed below the first or second printed circuit board, for a hardware interface for transmitting data and power, and for connection between electronic devices. A method for cleaning a base plate, characterized by the following steps include: (a) Welding a welding piece: Welding at least one welding piece onto a bonding base plate; (b) Covering with liquid material: A liquid material is filled between the bonding base plate and at least one of the solder pads to cover a substance to be cleaned on the bonding base plate; (c) Insertion into a chamber: The adhesive base plate containing the liquid material is placed in a chamber; (d) Controlling the chamber temperature: The chamber is controlled at at least a predetermined temperature, which is appropriate for the viscosity of the liquid material and is between 25 and 200°C. (e) Intermittent wave cleaning: A vacuum generator is used to intermittently control the low pressure of the gas in the chamber, causing the gas molecules in the chamber to generate a wave-like airflow, which is a low-pressure wave, ranging from a maximum of no more than 1 atmosphere to a minimum of 10 atmospheres. -5 Intermittent fluctuations in atmospheric pressure, utilizing the low-pressure fluctuations caused by the vacuum suction and release of gas, create fluctuations in the liquid material. This causes the liquid material in contact with the substance to be cleaned to be rubbed and washed by the fluctuations, thereby removing the substance to be cleaned from the adhesive base plate and the liquid material.

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