CN110956125A - Fingerprint identification circuit, driving method thereof and touch display panel - Google Patents
Fingerprint identification circuit, driving method thereof and touch display panel Download PDFInfo
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- CN110956125A CN110956125A CN201911184056.6A CN201911184056A CN110956125A CN 110956125 A CN110956125 A CN 110956125A CN 201911184056 A CN201911184056 A CN 201911184056A CN 110956125 A CN110956125 A CN 110956125A
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- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
- G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
- G06V40/12—Fingerprints or palmprints
- G06V40/13—Sensors therefor
- G06V40/1306—Sensors therefor non-optical, e.g. ultrasonic or capacitive sensing
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- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/0412—Digitisers structurally integrated in a display
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Abstract
The invention discloses a fingerprint identification circuit, a driving method thereof and a touch display panel.A reset module is used for resetting a first node before fingerprint identification is carried out, a control module is used for controlling an ultrasonic energy converter to transmit ultrasonic waves when fingerprint identification is carried out, and when fingerprints exist, the transmitted ultrasonic waves are reflected at the valley of the fingerprints due to the problem of acoustic impedance matching, and the ultrasonic waves are continuously transmitted at the ridge of the fingerprints. The reflected ultrasonic waves are received by the receiving ultrasonic energy converter, so that the point position of the first node is changed, the input module controls the signal value of the output end of the input module according to the potential of the first node, the output module provides the signal output by the input module for the signal reading end, and the image of the fingerprint can be obtained by detecting the signal of the signal reading end. The fingerprint identification circuit adopts different ultrasonic energy converters for transmitting and receiving ultrasonic waves, has a simple structure, and is simple in subsequent signal processing method, so that the accuracy of fingerprint imaging can be improved.
Description
Technical Field
The present invention relates to the field of fingerprint identification technologies, and in particular, to a fingerprint identification circuit, a driving method thereof, and a touch display panel.
Background
In recent years, with the rapid development of touch technology, mobile products with biometric identification function gradually enter people's life and work, and fingerprint technology is paid much attention by virtue of its unique identity characteristic. Fingerprint identification can be divided into: resistive, capacitive, infrared, ultrasonic, electromagnetic, vibration wave-induced, and frustrated total internal reflection optical induction, and the like.
Currently, ultrasonic fingerprint identification mostly uses ultrasonic waves in the MHz level for imaging, and when the propagation speed of the ultrasonic waves in a solid exceeds 1540m/s, the transmitted and received signals are generally detected simultaneously. In the existing ultrasonic fingerprint identification circuit, an ultrasonic transducer is mainly used for transmitting and receiving signals. The method comprises the steps of simultaneously acquiring transmitted and received signals, and judging valleys and ridges of fingerprints by complex signal comparison and other processing methods, so that fingerprint imaging is realized. However, this way of fingerprinting is complex and less accurate.
Disclosure of Invention
In view of this, embodiments of the present invention provide a fingerprint identification circuit, a driving method thereof, and a touch display panel, so as to implement an ultrasonic fingerprint identification circuit with a simple structure.
The embodiment of the invention provides a fingerprint identification circuit, which comprises: the ultrasonic energy transducer comprises an emitting ultrasonic energy transducer, a receiving ultrasonic energy transducer, an input module, a control module, a reset module and an output module;
the input end of the input module is connected with a first reference voltage, the control end of the input module is connected with a first node, and the output end of the input module is connected with the input end of the output module; the input module is used for controlling the signal value of the output end of the input module according to the potential of the first node;
the control end of the output module is connected with the reading control signal, and the output end of the output module is connected with the reading signal end; the output module is used for providing the signal received by the input end of the output module to the reading signal end under the control of the reading control signal;
the input end of the control module is connected with alternating current, the control end of the control module is connected with the reading control signal, and the output end of the control module is connected with the ultrasonic energy converter; the control module is used for providing alternating current to the transmitting ultrasonic energy converter under the control of the reading control signal so as to enable the transmitting ultrasonic energy converter to transmit ultrasonic waves;
the output end of the reset module is connected with a second reference voltage, the control end of the reset module is connected with a reset control signal, and the output end of the reset module is connected with the first node; the reset module is used for providing the second reference voltage to the first node under the control of the reset control signal so as to reset the potential of the first node;
the receiving ultrasonic energy converter is connected to the first node and used for receiving ultrasonic waves.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the input module includes a first transistor;
the gate of the first transistor is connected to the first node, the first pole of the first transistor is connected to the first reference voltage, and the second pole of the first transistor is connected to the input terminal of the output module.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the input module further includes a first capacitor;
the first capacitor is connected between the grid electrode and the first electrode of the first transistor.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the reset module includes a second transistor;
a gate of the second transistor is connected to the reset control signal, a first pole of the second transistor is connected to the second reference voltage, and a second pole of the second transistor is connected to the first node.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the control module includes a third transistor;
the grid electrode of the third transistor is connected with the reading control signal, the first pole of the third transistor is electrically connected with the alternating current, and the second pole of the third transistor is connected with the ultrasonic energy transmitting transducer.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the output module includes a fourth transistor;
the gate of the fourth transistor is connected to the read control signal, the first pole of the fourth transistor is connected to the output terminal of the input module, and the second pole of the fourth transistor is connected to the read signal terminal.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, all the switch transistors are N-type transistors or P-type transistors.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, the transmitting ultrasonic transducer and the receiving ultrasonic transducer are disposed in the same layer; or the like, or, alternatively,
the transmitting ultrasonic transducer and the receiving ultrasonic transducer are arranged in a stack.
Correspondingly, the embodiment of the invention also provides a touch display panel, which comprises a display panel and a plurality of fingerprint identification circuits provided by the embodiment of the invention.
Correspondingly, an embodiment of the present invention further provides a driving method of the fingerprint identification circuit, where the driving method includes:
a reset phase, in which the reset module provides the second reference voltage to the first node under the control of the reset control signal to reset the potential of the first node; the input module outputs a signal under the control of the first node;
in the reading stage, the control module provides alternating current to the transmitting ultrasonic energy converter under the control of the reading control signal; the transmitting ultrasonic energy converter transmits ultrasonic waves; when a finger touches, the ultrasonic energy receiving converter receives ultrasonic waves reflected by the finger and changes the potential of the first node; the input module controls the signal value of the output end of the input module according to the potential of the first node; the output module provides the signal output by the input module to the reading signal end under the control of the reading control signal.
The invention has the following beneficial effects:
according to the fingerprint identification circuit, the driving method thereof and the touch display panel provided by the embodiment of the invention, before fingerprint identification is carried out, the reset module is used for resetting the first node, when fingerprint identification is carried out, the control module is used for controlling the ultrasonic energy converter to transmit ultrasonic waves, when fingerprints exist, the transmitted ultrasonic waves are reflected at the valley of the fingerprints due to the problem of acoustic impedance matching, and the ultrasonic waves are continuously transmitted at the ridge of the fingerprints. The reflected ultrasonic waves are received by the receiving ultrasonic energy converter, so that the point position of the first node is changed, the input module controls the signal value of the output end of the input module according to the potential of the first node, the output module provides the signal output by the input module for the signal reading end, and the image of the fingerprint can be obtained by detecting the signal of the signal reading end. According to the fingerprint identification circuit provided by the embodiment of the invention, the transmission and the reception of the ultrasonic waves are performed by adopting different ultrasonic energy converters, the structure is simple, and the subsequent signal processing method is simple, so that the accuracy of fingerprint imaging can be improved.
Drawings
FIG. 1 is a schematic diagram of an ultrasonic fingerprint identification;
FIG. 2 is a schematic diagram of a fingerprint identification circuit according to an embodiment of the present invention;
FIG. 3 is a second schematic diagram of a fingerprint identification circuit according to an embodiment of the present invention;
fig. 4 is a third schematic structural diagram of a fingerprint identification circuit according to an embodiment of the present invention;
FIG. 5 is a timing diagram of an input/output circuit corresponding to the fingerprint recognition circuit shown in FIG. 4;
FIG. 6 is a second timing diagram of the input/output of the fingerprint recognition circuit shown in FIG. 4;
FIG. 7 is a schematic diagram of the surface potential variation of the fingerprint identification circuit shown in FIG. 4 when the ultrasonic transducer receives ultrasonic waves;
FIG. 8 is a schematic diagram of a partial structure of a fingerprint identification circuit according to an embodiment of the present invention;
FIG. 9 is a second schematic diagram of a partial structure of a fingerprint identification circuit according to an embodiment of the present invention;
fig. 10 is a flowchart of a driving method of a fingerprint identification circuit according to an embodiment of the present invention.
Detailed Description
The principle of ultrasonic fingerprint identification is shown in fig. 1, and the transmitted ultrasonic waves are reflected at the valleys of the fingerprint due to the problem of acoustic impedance matching. At the ridges of the fingerprint, the ultrasonic waves continue to propagate. By detecting the reflected ultrasonic signal, an image of the fingerprint can be obtained.
Based on the above, the invention provides a fingerprint identification circuit, a driving method thereof and a touch display panel.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, the present invention is further described with reference to the accompanying drawings and examples. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted. The words expressing the position and direction described in the present invention are illustrated in the accompanying drawings, but may be changed as required and still be within the scope of the present invention. The drawings of the present invention are for illustrative purposes only and do not represent true scale.
It should be noted that in the following description, specific details are set forth in order to provide a thorough understanding of the present invention. The invention can be implemented in a number of ways different from those described herein and similar generalizations can be made by those skilled in the art without departing from the spirit of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The description which follows is a preferred embodiment of the present application, but is made for the purpose of illustrating the general principles of the application and not for the purpose of limiting the scope of the application. The protection scope of the present application shall be subject to the definitions of the appended claims.
The fingerprint identification circuit, the driving method thereof and the touch display panel provided by the embodiment of the invention are specifically described below with reference to the accompanying drawings.
The fingerprint identification circuit provided by the embodiment of the invention, as shown in fig. 2, includes: the ultrasonic energy transmitting and receiving device comprises a transmitting ultrasonic energy converter 01, a receiving ultrasonic energy converter 02, an input module 03, a control module 04, a reset module 05 and an output module 06;
the input end of the input module 03 is connected with a first reference voltage V1, the control end is connected with a first node N1, and the output end is connected with the input end of the output module 06; the input module 03 is used for controlling the signal value of the output end thereof according to the potential of the first node N1;
the control end of the output module 06 is connected with a read control signal read, and the output end is connected with a read signal end Out; the output module 06 is configured to provide the signal received by the input terminal thereof to the read signal terminal Out under the control of the read control signal read;
the input end of the control module 04 is connected with alternating current, the control end is connected with a read control signal read, and the output end is connected with an ultrasonic energy converter 01; the control module 04 is used for providing alternating current to the transmitting ultrasonic transducer 01 under the control of the reading control signal read so as to enable the transmitting ultrasonic transducer 01 to transmit ultrasonic waves;
the output end of the reset module 05 is connected with a second reference voltage V2, the control end is connected with a reset control signal reset, and the output end is connected with a first node N1; the reset module 05 is configured to provide a second reference voltage V2 to the first node N1 under the control of a reset control signal reset to reset the potential of the first node N1;
the receiving ultrasonic transducer 02 is connected to the first node N1, and the receiving ultrasonic transducer 02 receives ultrasonic waves.
The fingerprint identification circuit provided by the embodiment of the invention utilizes the reset module to reset the first node before fingerprint identification, controls the ultrasonic energy converter to transmit ultrasonic waves through the control module during fingerprint identification, and transmits the ultrasonic waves at the valley of the fingerprint when the fingerprint exists, and the ultrasonic waves continue to propagate at the ridge of the fingerprint due to the reflection of the acoustic impedance matching problem. The reflected ultrasonic waves are received by the receiving ultrasonic energy converter, so that the point position of the first node is changed, the input module controls the signal value of the output end of the input module according to the potential of the first node, the output module provides the signal output by the input module for the signal reading end, and the image of the fingerprint can be obtained by detecting the signal of the signal reading end. According to the fingerprint identification circuit provided by the embodiment of the invention, the transmission and the reception of the ultrasonic waves are performed by adopting different ultrasonic energy converters, the structure is simple, and the subsequent signal processing method is simple, so that the accuracy of fingerprint imaging can be improved.
The present invention will be described in detail with reference to specific examples. It should be noted that the present embodiment is for better explaining the present invention, but not limiting the present invention.
Alternatively, in the fingerprint recognition circuit provided in the embodiment of the present invention, as shown in fig. 3, the input module 03 includes a first transistor T1;
a gate of the first transistor T1 is connected to the first node N1, a first pole of the first transistor T1 is connected to the first reference voltage V1, and a second pole of the first transistor T1 is connected to the input terminal of the output module 06.
In a specific implementation, the first transistor is turned on under the control of the first node, the first reference voltage provides a current signal to the output module through the turned-on first transistor, and the potential of the first node determines the magnitude of the current signal.
Specifically, the first transistor may be an N-type transistor or a P-type transistor, which is not limited herein. When the first transistor is an N-type transistor, the second reference voltage is greater than the first reference voltage, and when the first transistor is a P-type transistor, the second reference voltage is less than the first reference voltage.
Optionally, in the fingerprint identification circuit provided in the embodiment of the present invention, as shown in fig. 4, the input module 03 further includes a first capacitor C1; the first capacitor C1 is connected between the gate and the first pole of the first transistor T1. The first capacitor C1 is used to stabilize the potential of the first node N1, thereby improving the accuracy of the fingerprint identification circuit.
The above is merely an example of the specific structure of the input module in the fingerprint identification circuit, and in the specific implementation, the specific structure of the input module is not limited to the above structure provided by the embodiment of the present invention, and may be other structures known to those skilled in the art, and is not limited herein.
Alternatively, in the fingerprint identification circuit provided in the embodiment of the present invention, as shown in fig. 3, the reset module 05 includes a second transistor T2;
the gate of the second transistor T2 is connected to the reset control signal reset, the first pole of the second transistor T2 is connected to the second reference voltage V2, and the second pole of the second transistor T2 is connected to the first node N1.
In specific implementation, under the control of the reset control signal, the second transistor is turned on, the second reference voltage is provided to the first node through the turned-on second transistor, and the potential of the first node is reset, so that noise interference is reduced, and the accuracy of fingerprint identification is ensured.
Specifically, the second transistor may be an N-type transistor or a P-type transistor, which is not limited herein.
The above is merely an example of the specific structure of the reset module in the fingerprint identification circuit, and in the specific implementation, the specific structure of the reset module is not limited to the above structure provided by the embodiment of the present invention, and may be other structures known to those skilled in the art, and is not limited herein.
Alternatively, in the fingerprint identification circuit provided in the embodiment of the present invention, as shown in fig. 3, the control module 04 includes a third transistor T3;
the gate of the third transistor T3 is connected to the read control signal read, the first pole of the third transistor T3 is electrically connected to the ac, and the second pole of the third transistor T3 is connected to the transmitting ultrasonic transducer 01.
In specific implementation, under the control of the read control signal, the third transistor is turned on, and the turned-on third transistor supplies alternating current to the transmitting ultrasonic transducer so that the transmitting ultrasonic transducer transmits ultrasonic waves.
Specifically, the third transistor may be an N-type transistor or a P-type transistor, which is not limited herein.
The above is merely an example of the specific structure of the control module in the fingerprint identification circuit, and in the specific implementation, the specific structure of the control module is not limited to the above structure provided by the embodiment of the present invention, and may also be other structures known to those skilled in the art, and is not limited herein.
Alternatively, in the fingerprint recognition circuit provided in the embodiment of the present invention, as shown in fig. 3, the output module 06 includes a fourth transistor T4;
the gate of the fourth transistor T4 is connected to the read control signal read, the first pole of the fourth transistor T4 is connected to the output terminal of the input block 03, and the second pole of the fourth transistor T4 is connected to the read signal terminal Out.
In specific implementation, under the control of a reading control signal, the fourth transistor is turned on, a current signal output by the turned-on third transistor input module is provided for a reading signal end, when no fingerprint exists, a signal of the reading signal end is kept unchanged, when a fingerprint exists, if the fingerprint corresponds to a valley, the ultrasonic transducer is received to receive reflected ultrasonic waves, the potential of the first node is changed, the current signal output by the input module is changed, and the signal of the reading signal end is changed; if the ridge corresponds to the signal line, the reflected ultrasonic waves cannot be received by the ultrasonic energy receiving converter, the potential of the first node does not change, the current signal output by the input module does not change, and the signal at the signal reading end does not change.
Specifically, the fourth transistor may be an N-type transistor or a P-type transistor, which is not limited herein.
The above is merely an example of the specific structure of the output module in the fingerprint identification circuit, and in the specific implementation, the specific structure of the output module is not limited to the above structure provided by the embodiment of the present invention, and may be other structures known to those skilled in the art, and is not limited herein.
In a specific implementation, in the fingerprint identification circuit provided in the embodiment of the present invention, all the switch transistors are N-type transistors or P-type transistors, so that the manufacturing process flow of the pixel circuit can be simplified, which is not limited herein.
In a specific implementation, the switching Transistor may be a Thin Film Transistor (TFT) or a Metal Oxide Semiconductor field effect Transistor (MOS), and is not limited herein.
The operation of the fingerprint identification circuit provided in the embodiment of the present invention will be described below by taking the fingerprint identification circuit shown in fig. 4 as an example. And a high level signal is denoted by 1 and a low level signal is denoted by 0 in the following description.
In the pixel circuit shown in fig. 4, all the switching transistors are N-type transistors, and each N-type transistor is turned off under the action of a low level and turned on under the action of a high level; the corresponding circuit timing diagrams are shown in fig. 5 and 6. Specifically, when the fingerprint identification circuit works, the method comprises two stages: a reset phase and a read phase; wherein:
in the reset phase (T1), under the control of the reset control signal reset, the second transistor T2 is turned on, and the second reference voltage V2 is provided to the first node N1 through the turned-on second transistor T2, so as to reset the potential of the first node N1, thereby reducing noise interference and ensuring the accuracy of fingerprint identification. Under the control of the first node N1, the first transistor T1 is turned on.
During the read phase (T2), the first transistor T1 continues to be turned on under the control of the first node N1. The first capacitor C1 is used to stabilize the potential of the first node N1, thereby improving the accuracy of the fingerprint identification circuit. Under the control of the read control signal read, the third transistor T3 is turned on, and the turned-on third transistor T3 supplies alternating current to the transmitting ultrasonic transducer 01, so that the transmitting ultrasonic transducer 01 transmits ultrasonic waves. Under the control of the read control signal read, the fourth transistor T4 is turned on, the current signal output by the third transistor T3 is provided to the read signal terminal Out, when there is no fingerprint, the signal at the read signal terminal Out remains unchanged, when there is a fingerprint, if it corresponds to a valley, the receiving ultrasonic transducer 02 receives the reflected ultrasonic wave, the surface potential of the receiving ultrasonic transducer 02 changes, and the simulation result is as shown in fig. 7. The potential of the first node N1 is changed due to the change of the surface potential of the receiving ultrasonic transducer 02, the current signal output by the third transistor T3 is changed, and the signal of the reading signal end Out is changed; if the signal corresponds to the ridge, the ultrasonic transducer 02 cannot receive the reflected ultrasonic wave, the potential of the first node N1 does not change, the current signal output by the third transistor T3 does not change, and the signal at the read signal end Out does not change.
According to the fingerprint identification circuit provided by the embodiment of the invention, the transmission and the reception of the ultrasonic waves are performed by adopting different ultrasonic energy converters, the structure is simple, and the subsequent signal processing method is simple, so that the accuracy of fingerprint imaging can be improved.
Alternatively, in the fingerprint identification circuit provided in the embodiment of the present invention, as shown in fig. 8, the transmitting ultrasonic transducer 01 and the receiving ultrasonic transducer 02 are disposed in the same layer, so that the film layers having the same function as the transmitting ultrasonic transducer and the receiving ultrasonic transducer can be prepared in the same layer, thereby simplifying the process steps.
Alternatively, in the fingerprint recognition circuit provided in the embodiment of the present invention, as shown in fig. 9, the transmitting ultrasonic transducer 01 and the receiving ultrasonic transducer 02 are stacked, and the receiving ultrasonic transducer 02 is located on the side close to the finger, so that the area of the fingerprint recognition circuit can be saved.
It should be noted that fig. 8 and 9 are each illustrated by taking as an example the transmitting ultrasonic transducer 01 and the receiving ultrasonic transducer 02 in a plurality of fingerprint recognition circuits.
In the fingerprint identification circuit provided by the embodiment of the invention, the ultrasonic transducer is preferably a voltage type ultrasonic transducer.
Based on the same inventive concept, an embodiment of the present invention further provides a driving method of a fingerprint identification circuit, as shown in fig. 10, including:
s101, in a reset stage, a reset module supplies a second reference voltage to a first node under the control of a reset control signal so as to reset the potential of the first node; the input module outputs a signal under the control of the first node;
s102, in a reading stage, a control module supplies alternating current to an ultrasonic energy converter under the control of a reading control signal; the ultrasonic energy converter transmits ultrasonic waves; when a finger touches, the receiving ultrasonic energy converter receives ultrasonic waves reflected by the finger and changes the potential of the first node; the input module controls the signal value of the output end of the input module according to the potential of the first node; the output module provides the signal output by the input module to the read signal terminal under the control of the read control signal.
In specific implementation, because the principle of the driving method for solving the problem is similar to that of the fingerprint identification circuit, the implementation of the driving method can refer to the implementation of the fingerprint identification circuit, and repeated parts are not repeated.
Based on the same inventive concept, an embodiment of the present invention further provides a touch display panel, which includes a display panel and a plurality of fingerprint identification circuits provided in any one of the above embodiments of the present invention. Because the principle of solving the problems of the touch display panel is similar to that of the fingerprint identification circuit, the implementation of the touch display panel can refer to the implementation of the fingerprint identification circuit, and repeated parts are not described again.
In a specific implementation, in the touch display panel provided in the embodiment of the present invention, the fingerprint identification circuit may be integrated in the display panel, and certainly may be formed in a frame region of the display panel, or may be externally hung on the display panel, which is not limited herein.
According to the fingerprint identification circuit, the driving method thereof and the touch display panel provided by the embodiment of the invention, before fingerprint identification is carried out, the reset module is used for resetting the first node, when fingerprint identification is carried out, the control module is used for controlling the ultrasonic energy converter to transmit ultrasonic waves, when fingerprints exist, the transmitted ultrasonic waves are reflected at the valley of the fingerprints due to the problem of acoustic impedance matching, and the ultrasonic waves are continuously transmitted at the ridge of the fingerprints. The reflected ultrasonic waves are received by the receiving ultrasonic energy converter, so that the point position of the first node is changed, the input module controls the signal value of the output end of the input module according to the potential of the first node, the output module provides the signal output by the input module for the signal reading end, and the image of the fingerprint can be obtained by detecting the signal of the signal reading end. According to the fingerprint identification circuit provided by the embodiment of the invention, the transmission and the reception of the ultrasonic waves are performed by adopting different ultrasonic energy converters, the structure is simple, and the subsequent signal processing method is simple, so that the accuracy of fingerprint imaging can be improved.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A fingerprint identification circuit, comprising: the ultrasonic energy transducer comprises an emitting ultrasonic energy transducer, a receiving ultrasonic energy transducer, an input module, a control module, a reset module and an output module;
the input end of the input module is connected with a first reference voltage, the control end of the input module is connected with a first node, and the output end of the input module is connected with the input end of the output module; the input module is used for controlling the signal value of the output end of the input module according to the potential of the first node;
the control end of the output module is connected with the reading control signal, and the output end of the output module is connected with the reading signal end; the output module is used for providing the signal received by the input end of the output module to the reading signal end under the control of the reading control signal;
the input end of the control module is connected with alternating current, the control end of the control module is connected with the reading control signal, and the output end of the control module is connected with the ultrasonic energy converter; the control module is used for providing alternating current to the transmitting ultrasonic energy converter under the control of the reading control signal so as to enable the transmitting ultrasonic energy converter to transmit ultrasonic waves;
the output end of the reset module is connected with a second reference voltage, the control end of the reset module is connected with a reset control signal, and the output end of the reset module is connected with the first node; the reset module is used for providing the second reference voltage to the first node under the control of the reset control signal so as to reset the potential of the first node;
the receiving ultrasonic energy converter is connected to the first node and used for receiving ultrasonic waves.
2. The fingerprint identification circuit of claim 1, wherein the input module comprises a first transistor;
the gate of the first transistor is connected to the first node, the first pole of the first transistor is connected to the first reference voltage, and the second pole of the first transistor is connected to the input terminal of the output module.
3. The fingerprint recognition circuit of claim 2, wherein said input module further comprises a first capacitance;
the first capacitor is connected between the grid electrode and the first electrode of the first transistor.
4. The fingerprint identification circuit of claim 1, wherein the reset module comprises a second transistor;
a gate of the second transistor is connected to the reset control signal, a first pole of the second transistor is connected to the second reference voltage, and a second pole of the second transistor is connected to the first node.
5. The fingerprint identification circuit of claim 1, wherein the control module comprises a third transistor;
the grid electrode of the third transistor is connected with the reading control signal, the first pole of the third transistor is electrically connected with the alternating current, and the second pole of the third transistor is connected with the ultrasonic energy transmitting transducer.
6. The fingerprint identification circuit of claim 1, wherein the output module comprises a fourth transistor;
the gate of the fourth transistor is connected to the read control signal, the first pole of the fourth transistor is connected to the output terminal of the input module, and the second pole of the fourth transistor is connected to the read signal terminal.
7. The fingerprint identification circuit of any of claims 2-6, wherein all of the switching transistors are N-type transistors or are P-type transistors.
8. The fingerprinting circuit of claim 1, wherein the transmit ultrasound transducer and the receive ultrasound transducer are disposed in a same layer; or the like, or, alternatively,
the transmitting ultrasonic transducer and the receiving ultrasonic transducer are arranged in a stack.
9. A touch display panel comprising a display panel and a plurality of fingerprint recognition circuits according to any one of claims 1 to 8.
10. A method of driving a fingerprint recognition circuit according to any one of claims 1 to 8, comprising:
a reset phase, in which the reset module provides the second reference voltage to the first node under the control of the reset control signal to reset the potential of the first node; the input module outputs a signal under the control of the first node;
in the reading stage, the control module provides alternating current to the transmitting ultrasonic energy converter under the control of the reading control signal; the transmitting ultrasonic energy converter transmits ultrasonic waves; when a finger touches, the ultrasonic energy receiving converter receives ultrasonic waves reflected by the finger and changes the potential of the first node; the input module controls the signal value of the output end of the input module according to the potential of the first node; the output module provides the signal output by the input module to the reading signal end under the control of the reading control signal.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111553325A (en) * | 2020-05-26 | 2020-08-18 | 上海天马微电子有限公司 | Fingerprint identification circuit, driving method and display device |
| CN111709373A (en) * | 2020-06-18 | 2020-09-25 | 上海天马微电子有限公司 | Ultrasonic fingerprint identification circuit, driving method thereof and display device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108776797A (en) * | 2018-07-03 | 2018-11-09 | 京东方科技集团股份有限公司 | A kind of fingerprint recognition circuit and its driving method, display device |
| US20190057236A1 (en) * | 2017-02-28 | 2019-02-21 | Boe Technology Group Co., Ltd. | Display panel, driving method therefor, and display device |
| CN110010046A (en) * | 2019-04-22 | 2019-07-12 | 京东方科技集团股份有限公司 | Display panel, its detection method and display device |
| CN110097043A (en) * | 2019-05-05 | 2019-08-06 | 京东方科技集团股份有限公司 | Sensor pixel, ultrasonic sensor, OLED display panel and OLED display |
-
2019
- 2019-11-27 CN CN201911184056.6A patent/CN110956125B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20190057236A1 (en) * | 2017-02-28 | 2019-02-21 | Boe Technology Group Co., Ltd. | Display panel, driving method therefor, and display device |
| CN108776797A (en) * | 2018-07-03 | 2018-11-09 | 京东方科技集团股份有限公司 | A kind of fingerprint recognition circuit and its driving method, display device |
| CN110010046A (en) * | 2019-04-22 | 2019-07-12 | 京东方科技集团股份有限公司 | Display panel, its detection method and display device |
| CN110097043A (en) * | 2019-05-05 | 2019-08-06 | 京东方科技集团股份有限公司 | Sensor pixel, ultrasonic sensor, OLED display panel and OLED display |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111553325A (en) * | 2020-05-26 | 2020-08-18 | 上海天马微电子有限公司 | Fingerprint identification circuit, driving method and display device |
| CN111553325B (en) * | 2020-05-26 | 2023-11-24 | 上海天马微电子有限公司 | Fingerprint identification circuit, driving method and display device |
| CN111709373A (en) * | 2020-06-18 | 2020-09-25 | 上海天马微电子有限公司 | Ultrasonic fingerprint identification circuit, driving method thereof and display device |
| CN111709373B (en) * | 2020-06-18 | 2023-07-18 | 上海天马微电子有限公司 | Ultrasonic fingerprint identification circuit, driving method thereof and display device |
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