Fingerprint recognition device and fingerprint recognition method thereof

Abstract

The fingerprint recognition device of the present invention comprises: a substrate; a sensor located on the substrate and surrounded by a plurality of sensing finger touch pads; an oscillator electrically connected to the plurality of sensing finger touch pads and outputting at least one oscillation frequency signal; a timer outputting a clock signal to the oscillator; and a counting and digital comparator counting and comparing the oscillation frequency signal. The fingerprint recognition method of the present invention comprises: the oscillator receiving the clock signal and outputting the oscillation frequency signal; a finger touching the plurality of sensing finger touch pads; and counting and comparing the oscillation frequency signal and the oscillation frequency signal after touching. The present invention is applied to the display surface of an electronic product and senses whether a finger touches the fingerprint recognition device.

Description

Technical Field

[0001] The present invention relates to the field of fingerprint recognition, and more particularly to a fingerprint recognition device and a fingerprint recognition method thereof. Background Art

[0002] Biometric technologies, such as fingerprint recognition, voiceprint recognition, and retinal recognition, have gradually matured and are widely used in personal identification and confirmation. Since fingerprint feature data requires less storage space than other types of biometric feature data, fingerprint recognition has become the mainstream of biometric technology. Therefore, many products on the market, such as laptops, tablets, and mobile phones, have integrated fingerprint recognition functions to improve safety.

[0003] Since conventional capacitive fingerprint recognition devices require an external frame (such as an iron frame) to contact the user's finger to determine whether a touch event has occurred, if the fingerprint recognition device is to be attached to the display surface of an electronic product, this will reduce the visibility of the display surface, thereby limiting the application of the fingerprint recognition device to a specific position of the electronic product, and the additional external frame also increases the manufacturing cost of the fingerprint recognition device.

[0004] In view of the fact that the above-mentioned prior art can be improved, the inventor provides a fingerprint recognition device and a fingerprint recognition method thereof to solve the shortcomings of the conventional fingerprint recognition device. Summary of the invention

[0005] The main purpose of the present invention is to provide a fingerprint recognition device which can be applied to the display surface of a product without an additional frame.

[0006] Another object of the present invention is to provide a fingerprint recognition device that does not require an additional frame, thereby reducing the manufacturing cost of the conventional fingerprint recognition device.

[0007] Another object of the present invention is to provide a fingerprint recognition method for a fingerprint recognition device, which can effectively sense whether a finger touches the fingerprint recognition device.

[0008] The present invention provides a fingerprint recognition device and a fingerprint recognition method thereof. The fingerprint recognition device of the present invention comprises: a substrate; a sensor located on the substrate and comprising a plurality of finger image sensing pads and a plurality of sensing finger touch pads, wherein the plurality of sensing finger touch pads surround the periphery of the plurality of finger image sensing pads; an oscillator electrically connected to the plurality of sensing finger touch pads and outputting at least one oscillation frequency signal; a timer outputting a clock signal to the oscillator; and a counting and digital comparator receiving the oscillation frequency signal and counting and comparing the oscillation frequency signal to determine whether a finger touching the plurality of sensing finger touch pads is a valid touch event; wherein when it is determined to be a valid touch event, the plurality of finger image sensing pads are activated to sense the user's finger image.

[0009] In an embodiment of the fingerprint recognition device of the present invention, the plurality of sensing finger touch pads are arranged in the 1st to 3rd rows at the outermost periphery of the sensor.

[0010] In an embodiment of the fingerprint recognition device of the present invention, the sensor is further covered with a dielectric layer.

[0011] In one embodiment of the fingerprint recognition device of the present invention, the oscillator, the timer, and the counter and digital comparator are all disposed in a chip.

[0012] In one embodiment of the fingerprint recognition device of the present invention, when the finger touches the sensor, a touch capacitance is generated between the finger and the plurality of sensing finger touch pads, and the counter and digital comparator detects that the number of oscillations of the oscillation frequency signal within a predetermined time after the touch is reduced, that is, the frequency of the oscillation frequency signal is reduced.

[0013] An embodiment of the fingerprint recognition method of the fingerprint recognition device of the present invention comprises the following steps: providing the fingerprint recognition device with a voltage source and calibrating it; the oscillator receiving the clock signal output by the timer and outputting the oscillation frequency signal; a finger touching the plurality of sensing finger touch pads to generate a touch capacitance and affect the oscillation frequency signal; and the counter and digital comparator receiving the oscillation frequency signal and the oscillation frequency signal after the touch, counting and comparing them, the counter and digital comparator measuring that the number of oscillations of the oscillation frequency signal after the touch within a predetermined time is reduced, that is, the frequency of the oscillation frequency signal is reduced, and when the number of oscillations within the predetermined time is reduced or the frequency of the oscillation frequency signal is reduced to a predetermined value, it indicates that the finger touching the plurality of sensing finger touch pads is a valid touch event, and the plurality of finger image sensing pads are activated to sense the user's finger image.

[0014] The advantages of the present invention are:

[0015] The fingerprint identification device provided by the present invention does not need to be additionally matched with an outer frame, and can be applied to the display surface of a product.

[0016] Furthermore, no additional frame is required, thus reducing the manufacturing cost of the conventional fingerprint recognition device.

[0017] The fingerprint recognition method of the fingerprint recognition device provided by the present invention can effectively sense whether a finger touches the fingerprint recognition device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. 1 is a top view of a fingerprint recognition device according to an embodiment of the present invention.

[0019] Figure 2 FIG. 4 is a schematic side view of a fingerprint recognition device according to an embodiment of the present invention.

[0020] Figure 3 It is a side view schematic diagram of a fingerprint recognition device according to an embodiment of the present invention, showing a finger touching the fingerprint recognition device.

[0021] Figure 4 FIG. 1 is a flowchart of the steps of a fingerprint recognition method of a fingerprint recognition device according to an embodiment of the present invention.

[0022] Figure 5 Various signal waveform diagrams of an embodiment of the fingerprint recognition device and the fingerprint recognition method thereof of the present invention. DETAILED DESCRIPTION

[0023] Please refer to Figures 1 to 3 , a fingerprint recognition device according to an embodiment of the present invention comprises:

[0024] A substrate 1; a sensor 2, located on the substrate 1, and the sensor 2 includes a plurality of finger image sensing pads and a plurality of sensing finger touch pads 21, the plurality of sensing finger touch pads surrounding the periphery of the plurality of finger image sensing pads; an oscillator 3, which is electrically connected to the plurality of sensing finger touch pads 21 through a plurality of nodes NA and outputs at least one oscillation frequency signal 31; a timer 4, outputting a clock signal 41 to the oscillator 3; and a counting and digital comparator 5, receiving the oscillation frequency signal 31, and counting and comparing the oscillation frequency signal 31, thereby determining whether a finger 6 touching the plurality of sensing finger touch pads is a valid touch event; wherein, when it is determined to be a valid touch event, the plurality of finger image sensing pads are activated to sense the user's finger image.

[0025] The sensor 2 of the fingerprint recognition device is further covered with a dielectric layer 71 and another dielectric layer 72. The dielectric layer 71 represents a dielectric material for encapsulating the sensing finger touch pad 21, and the dielectric layer 72 is a dielectric material for contacting the finger to be detected, such as glass. Since the substrate 1, the sensor 2 and the dielectric layers 71 and 72 are all composed of transparent materials, the fingerprint recognition device is arranged on a display surface (not shown) of an electronic product in this embodiment, but it is not limited to this. The fingerprint recognition device can also be arranged at other parts of the electronic product.

[0026] The plurality of finger sensing touch pads 21 are arranged at the 1st to 3rd rows at the outermost periphery of the sensor 2. In the present embodiment, the plurality of finger sensing touch pads 21 are arranged at the 1st row at the outermost periphery of the sensor 2. The plurality of finger image sensing pads 22 located at the center of the sensor 2 are used to sense a finger image. When the finger image is confirmed to be the user's own finger image, the display device is unlocked.

[0027] When the finger 6 does not touch the plurality of sensing finger touch pads 21, a pair of ground capacitors Cp (eg Figure 2 As shown in FIG. 1 , when the finger 6 touches the plurality of sensing finger touch pads 21, a touch capacitance Cs (as shown in FIG. 1 ) is generated between the finger 6 and the plurality of sensing finger touch pads 21. Figure 3 As shown), the counter and digital comparator 5 detects that the number of oscillations of the oscillation frequency signal 31 after the touch within a predetermined time is reduced, that is, the frequency of the oscillation frequency signal is reduced.

[0028] In addition, the oscillator 3 , the timer 4 , and the counter and digital comparator 5 are all disposed in a chip 8 . The chip 8 is an integrated chip for fingerprint recognition and touch control, but is not limited thereto.

[0029] Please refer to Figure 4 and Figure 5 The fingerprint recognition method of the fingerprint recognition device according to an embodiment of the present invention comprises the following steps:

[0030] Step 1: Provide the fingerprint recognition device with a voltage source and calibrate it (see Figure 5 The start-up voltage and calibration signal in );

[0031] Step 2: The oscillator 3 receives the clock signal output by the timer 4 ( Figure 5 The clock signal in the oscillation frequency signal ( Figure 5 oscillation frequency signal in );

[0032] Step 3: The finger 6 touches the plurality of sensing finger touch pads 21 to generate the touch capacitance Cs and affect the oscillation frequency signal 31; and

[0033] Step 4: The counter and digital comparator 5 receives the oscillation frequency signal 31 ( Figure 5 The oscillation frequency signal before the touch event) and the oscillation frequency signal after the touch 31 ( Figure 5 The oscillation frequency signal after the touch event) is counted, memorized and compared.

[0034] The counter and digital comparator 5 detects that the oscillation frequency signal 31 after the touch is within a predetermined time ( Figure 5 The number of oscillations within tduty in (tduty) decreases, that is, the frequency of the oscillation frequency signal decreases.

[0035] In addition, when the number of oscillations within the predetermined time is reduced or the frequency of the oscillation frequency signal is reduced to a predetermined value, it indicates that the finger touching the plurality of sensing finger touch pads is a valid touch event, and then the plurality of finger image sensing pads 22 in the center of the sensor 2 are activated to sense the user's finger image, thereby avoiding the user's accidental touch and saving power.

[0036] In summary, the fingerprint recognition device and the fingerprint recognition method of the present invention do not need an additional frame, can be applied to the display surface of electronic products, reduce the manufacturing cost of the fingerprint recognition device, and can effectively sense whether a finger touches the fingerprint recognition device.

[0037] Although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. Any person having ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A fingerprint recognition device, characterized in that: include: a substrate; A sensor, located on the substrate, includes a plurality of finger image sensing pads and a plurality of sensing finger touch pads, wherein the plurality of sensing finger touch pads surround the periphery of the plurality of finger image sensing pads; an oscillator electrically connected to the plurality of sensing finger touch pads and outputting at least one oscillation frequency signal; a timer, outputting a clock signal to the oscillator; and a counter and digital comparator, receiving the oscillation frequency signal, and counting and comparing the oscillation frequency signal, thereby determining whether a finger touching the plurality of sensing finger touch pads is a valid touch event; When a valid touch event is determined, the plurality of finger image sensing pads are activated to sense the user's finger image.

2. The fingerprint recognition device according to claim 1, wherein: The plurality of sensing finger touch pads are arranged in the 1st to 3rd rows at the outermost periphery of the sensor.

3. The fingerprint recognition device according to claim 1, wherein: The sensor is further covered with a dielectric layer.

4. The fingerprint recognition device according to claim 1, wherein: The finger touches the sensor, and a touch capacitance is generated between the finger and the plurality of sensing finger touch pads. The counter and digital comparator detect that the number of oscillations of the oscillation frequency signal after the touch is reduced within a predetermined time, that is, the frequency of the oscillation frequency signal is reduced.

5. A fingerprint recognition method of the fingerprint recognition device as claimed in claim 1, characterized in that: The steps include: Providing the fingerprint recognition device with a voltage source and calibrating it; The oscillator receives the clock signal output by the timer and outputs the oscillation frequency signal; A finger touches the plurality of sensing finger touch pads to generate a touch capacitance and affect the oscillation frequency signal; and The counter and digital comparator receives the oscillation frequency signal and the oscillation frequency signal after the touch, and counts and compares them. The counter and digital comparator detects that the oscillation frequency signal after the touch has a reduced number of oscillations within a predetermined time, that is, the frequency of the oscillation frequency signal has decreased. When the number of oscillations within the predetermined time is reduced or the frequency of the oscillation frequency signal is reduced to a predetermined value, it indicates that the finger has touched. The plurality of finger image sensing pads are a valid touch event, and the plurality of finger image sensing pads are activated. To sense the user's finger image.

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