KR101730842B1 - Apparatus for recognizing biometric information and method for activating a plurality of piezoelectric element individually - Google Patents

Abstract

The present invention relates to an apparatus for recognizing biometric information and a method for selectively activating a plurality of piezoelectric elements by the apparatus. In detail, the present invention relates to an apparatus for recognizing biometric information and a driving method thereof, capable of recognizing fingerprints, blood vessels, and bones of a finger to identify an individual user. Particularly, the plurality of piezoelectric elements provided in the apparatus for recognizing biometric information can be activated individually. Therefore, the present invention provides a methodology for scanning biometric information by selectively activating the piezoelectric elements in a manner different from that of the related art.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for selectively activating a plurality of piezoelectric elements, and a biometric information recognition apparatus for the same. [0002]

The present invention relates to a biometric information recognition device and a method for the device to selectively activate a plurality of piezoelectric elements. More particularly, the present invention relates to a biometric information recognizing apparatus and a driving method thereof that can be used for identifying individual users by recognizing biometric information such as fingerprints, blood vessels, and bones of a finger, and more particularly, And a method for scanning biometric information in a different manner than the conventional method by selectively activating the piezoelectric elements.

User authentication is a necessary procedure for all financial transactions. Especially, as interest in mobile finance has been increased due to development of networks and portable terminals, demand for fast and accurate user authentication devices and authentication methods is increasing.

On the other hand, the fingerprint of the user is one of the authentication parameters that can satisfy the above demand, and many businesses and developers continue to develop devices and methods that can authenticate using the fingerprint of the user.

2. Description of the Related Art In recent years, studies on a so-called ultrasound method for detecting a shape of a fingerprint by generating an ultrasonic wave out of a conventional method of capturing an image of a fingerprint using an optical system have been actively conducted.

In order to grasp the biometric information of a user as an ultrasonic signal, various technical ideas are required. In particular, the present invention relates to a biometric authentication method for scanning a biometric information of a user, more precisely, a fingerprint, a blood vessel, In particular, the present invention selectively activates a plurality of piezoelectric elements formed on a substrate so that an efficient scanning pattern can be realized.

The present invention has been invented based on such a technical background and has been invented to provide additional technical elements that can not easily be invented by those skilled in the art as well as satisfying the technical requirements of the present invention.

Korean Patent Publication No. 10-2005-0047921 (published on May 23, 2005)

An object of the present invention is to allow a biometric information recognizing device to selectively activate a plurality of piezoelectric elements to scan biometric information of a user, more specifically, a shape of a fingerprint, a blood vessel, and a bone of a user.

Particularly, at this time, the biometric information recognizing device sets and activates a specific piezoelectric element among a plurality of piezoelectric elements as a signal generating element and at least one piezoelectric element among the piezoelectric elements other than the signal generating element as a signal receiving element, And to selectively drive the piezoelectric elements in an area where generation and reflected wave reception are required.

In order to solve the above problems, the piezoelectric element activation method according to the present invention

The biometric information recognizing device comprises: (a) setting a specific piezoelectric element among the plurality of piezoelectric elements as a signal generating element; (b) setting at least one piezoelectric element among the piezoelectric elements other than the signal generating element as a signal receiving element; (c) activating the signal generating element to generate an ultrasonic signal; (d) activating the signal receiving element to receive the reflected wave signal, wherein the reflected wave signal is reflected by the living tissue by the ultrasonic signal generated by the signal generating element, wherein the plurality of piezoelectric And the elements are arranged in a matrix form having a plurality of rows and a plurality of columns.

In the piezoelectric element activation method, in the step (b), at least one piezoelectric element in proximity to the signal generating element is set as a signal receiving element.

(E) setting any one of the plurality of piezoelectric elements adjacent to the signal generating element to a new signal generating element after the step (d); (F) setting at least one piezoelectric element in proximity to the new signal generating element to a new signal receiving element; (G) generating an ultrasonic signal by activating a newly set signal generating element in the step (e); Wherein the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue in the step (h), wherein the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue after receiving the reflected wave signal by activating the newly set signal receiving element in the step ; ≪ / RTI >

Further, the biometric information recognizing device repeatedly performs steps (a) to (h), wherein the signal generating elements set in the steps (a) and (e) And is a device.

Alternatively, the biometric information recognizing device repeatedly performs the steps (a) to (h), wherein the signal generating elements set in the steps (a) and (e) are piezoelectric elements arranged in a diagonal direction You may.

On the other hand, in the piezoelectric element activation method, a plurality of piezoelectric elements are given a unique identifier, and the biological information recognition apparatus sets and activates the signal generating element and the signal receiving element based on the unique identifier .

In the piezoelectric element activation method, the biological information recognition apparatus measures the magnitude of the reflected wave signal received in step (d), adjusts the magnitude of the ultrasonic signal generated in step (g) according to the magnitude of the reflected wave signal, .

Further, in the piezoelectric element activation method, the biological information recognition device compares the magnitudes of the reflected wave signals received in the steps (d) and (h), and determines a newly generated signal generating element And the size of the generated ultrasonic signal is adjusted.

In the piezoelectric element activation method, the biotissue may be at least one of a fingerprint, a blood vessel, and a bone.

According to another aspect of the present invention, there is provided a biometric information recognizing apparatus comprising: a substrate; A plurality of piezoelectric elements arranged on the substrate in a matrix form having a plurality of rows and a plurality of columns; A controller selectively activating the plurality of piezoelectric elements; Wherein the control unit sets a specific piezoelectric element among the plurality of piezoelectric elements as a signal generating element and sets at least one of the piezoelectric elements other than the signal generating element as a signal receiving element, The ultrasonic signal is generated by activating the signal receiving element, and the reflected signal is received by the signal receiving element, wherein the ultrasonic signal is reflected by the living tissue.

According to the present invention, it is possible to selectively activate a plurality of piezoelectric elements, thereby achieving a more efficient scanning pattern than an apparatus having a structure in which a single row or a whole column must be activated.

In addition, according to the present invention, only the piezoelectric elements necessary for recognizing the user's biometric information can be driven, so that power consumption can be reduced. Particularly, such an effect is advantageous in that the biometric information recognition device is gradually miniaturized, And the fact that it is borrowed from a smaller portable terminal.

According to the present invention, it is possible to activate the piezoelectric elements in a time series along one row, and thus the magnitude of the ultrasonic signal to be generated next can be adjusted by comparing the magnitude of the received reflected wave at each turn.

Fig. 1 shows a scanning method in a conventional biometric information recognizing apparatus.
2 schematically shows a basic configuration of a biometric information recognition apparatus according to the present invention.
FIG. 3 is a view illustrating an arrangement of piezoelectric elements in a biometric information recognizing apparatus according to the present invention.
FIG. 4 is a flowchart showing an embodiment in which a biometric information recognizing device according to the present invention selectively activates a plurality of piezoelectric elements.
FIG. 5 shows an example of the embodiment of FIG. 4 implemented on a biometric information recognition apparatus.
6 is a flowchart showing an embodiment in which the biometric information recognizing device according to the present invention activates a plurality of piezoelectric elements in a time-wise manner.
FIG. 7 shows an example of implementation of the embodiment of FIG. 6 on a biometric information recognition apparatus.
8 and 9 show an embodiment in which the size of the ultrasonic signal generated from the signal generating device is adjusted by the biometric information recognizing device.

DETAILED DESCRIPTION OF THE EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

The embodiments disclosed herein should not be construed or interpreted as limiting the scope of the present invention. It will be apparent to those of ordinary skill in the art that the description including the embodiments of the present specification has various applications. Accordingly, any embodiment described in the Detailed Description of the Invention is illustrative for a better understanding of the invention and is not intended to limit the scope of the invention to embodiments.

The functional blocks shown in the drawings and described below are merely examples of possible implementations. In other implementations, other functional blocks may be used without departing from the spirit and scope of the following detailed description. Also, although one or more functional blocks of the present invention are represented as discrete blocks, one or more of the functional blocks of the present invention may be a combination of various hardware and software configurations that perform the same function.

In addition, the expression "including any element" is merely an expression of an open-ended expression, and is not to be construed as excluding the additional elements.

Further, when a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it should be understood that there may be other components in between.

Also, the expressions such as 'first, second', etc. are used only to distinguish a plurality of configurations, and do not limit the order or other features between configurations.

When a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" to another part in between. Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

Hereinafter, a biometric information scanning method according to the present invention, that is, a method for selectively activating a piezoelectric element, as a biometric information scanning method in a conventional system and a means for solving the biometric information scanning method will be described with reference to the drawings.

FIG. 1 shows a fingerprint scanning process of a conventional fingerprint recognition device.

According to the conventional fingerprint recognition apparatus, a plurality of long conductive lines are arranged in a plane on a substrate, ceramic-based piezoelectric elements of a fine structure are arranged on the conductive lines, and a voltage is supplied to a specific conductive line So that all the piezoelectric elements on the conductive line are activated to generate ultrasonic waves and the piezoelectric elements on the other conductive line 13 are all activated for reception so that the ultrasonic waves are reflected on the fingerprint of the user Thereby recognizing the fingerprint of the user.

That is, in the case of the conventional ultrasonic fingerprint recognition device, activation is possible for each conductive line, so that all the piezoelectric elements formed on the conductive line can not be activated.

However, since the driving method as shown in FIG. 1 requires a plurality of piezoelectric elements to be activated at the same time, there is a problem of power consumption, and thus the fingerprint recognition device of this type is not suitable for a portable terminal which is becoming smaller and smaller.

2 schematically shows a configuration of a biometric information recognizing apparatus according to the present invention conceptually.

2, the biometric information recognizing apparatus according to the present invention includes a substrate 110 as an essential component, a plurality of piezoelectric elements 130 formed on the substrate 110, and a plurality of piezoelectric elements 130 selectively activated And a control unit 150 for controlling the operation of the apparatus.

First, the substrate 110 is a plate on which a plurality of piezoelectric elements 130 are formed, and means an insulating material capable of forming a conductor pattern on the surface of the insulating substrate 110. The substrate 110 may be rigid or flexible in its own right. The material for the substrate 110 may be chemically reinforced / semi-tempered glass such as soda lime glass or aluminosilicate glass, polyimide, polyethylene Reinforced or soft plastics such as terephthalate, propylene glycol, and polycarbonate, sapphire, and the like.

The substrate 110 may be a flexible substrate 110 having a flexible property, a curved substrate 110, or a bended substrate 110, The biometric information recognizing device can also have flexible, curve, and bend characteristics according to the use and function of the terminal to be provided with the biometric information recognizing device.

Meanwhile, as a preferred embodiment, the substrate 110 may be a PCB (printed circuit board 110). The PCB substrate 110 is a wiring board that represents electrical wiring connecting the circuit components based on the circuit design, and can reproduce the electric conductor on the insulating material. And the parts other than the electrical connection function of the parts can be fixed firmly.

Meanwhile, the biometric information recognizing apparatus according to the present invention may further include a cover substrate 300. The cover substrate 300 is formed above a plurality of piezoelectric elements 130 formed on the substrate 110, which means a substrate directly touching the user's finger. The cover substrate may be made of the same material as the substrate 110 described above, but may be preferably made of glass. Figs. 5 and 8 show an example of forming the cover substrate 300. Fig.

The plurality of piezoelectric elements 130 formed on the substrate 110 function to generate an ultrasonic signal or receive the reflected ultrasonic signal from the outside. The piezoelectric elements 130 are formed on a substrate 110, a pattern of a desired shape may be formed by a designer, and then a material mixed with lead, zirconium, and titanium may be coated on the patterned electrode.

The piezoelectric elements 130 according to the present invention are different from conventional fingerprint recognition devices in that the ceramic structures are individually arranged on the substrate 110 or the conductive electrodes, And a coating layer of a PZT component is laminated on the arbitrary shaped electrode to form a group of the piezoelectric elements 130. There is a difference in the process. A method of laminating a coating layer of a PZT component on the electrode may include a method of putting the substrate 110 with electrode patterning in a solution containing a PZT component or a method of coating a PZT component coating layer And a method of transferring the toner particles.

Meanwhile, the biometric information recognizing device according to the present invention assumes that the piezoelectric elements 130 are formed as shown in FIG. That is, in the case where the piezoelectric elements 130 are formed according to the above-described method, the arrangements of the piezoelectric elements 130 may vary depending on the shape of the electrode patterned on the substrate 110 by the designer, 3, a description will be given on the assumption that a plurality of piezoelectric elements 130 form a matrix.

3, a plurality of piezoelectric elements 130 are arranged in a lateral direction to form one row, and a plurality of another plurality of piezoelectric elements 130 are arranged in a longitudinal direction to form one row Can be achieved. Also, at this time, the respective rows may be formed preferably at equal intervals, which can be similarly applied to columns. When this arrangement is viewed from the perspective of one particular piezoelectric element 130, there are other piezoelectric elements 130 on the top / bottom / left / right of the particular piezoelectric element 130, The distance to the piezoelectric elements 130 may be constant.

The plurality of piezoelectric elements 130 formed in this manner can function as the signal generating element 131 each capable of generating ultrasonic waves or as the signal receiving element 133 receiving the reflected wave reflected by the user, Which of the piezoelectric elements 130 is activated as a functioning element is controlled by the controller 150, which will be described later.

The control unit 150 selectively activates the plurality of piezoelectric elements 130 as described above.

Specifically, the control unit 150 sets a part of the plurality of piezoelectric elements 130 existing on the substrate 110 to the signal generating element 131 and the other part to the signal receiving element 133, By activating the elements according to their functions, the activated elements generate ultrasound signals and receive reflected waves to control the user's biometric information.

The control unit 150 may include at least one computing means and a storing means. The computing means may be a general-purpose central processing unit (CPU), a programmable device element (CPLD, FPGA), an application specific integrated circuit (ASIC), or a microcontroller chip. In addition, a volatile memory element, a non-volatile memory element, or a non-volatile electromagnetic storage element may be utilized as the storage means.

In the meantime, each of the piezoelectric elements 130 according to the present invention can be individually activated, and the controller 150 can also control the individual piezoelectric elements 130 by dividing them into independent identifiers, It is possible to implement a user biometric information recognition process, i.e., a scanning process, in a completely different manner from the apparatus.

Hereinafter, how the control unit 150 can selectively activate the piezoelectric elements 130 and how a scanning process for grasping the user's biometric information is implemented will be described with reference to the drawings.

4 and 5 illustrate a first embodiment of a method of activating the piezoelectric element 130 according to the present invention. A method of selectively activating the biometric information recognition device, or more precisely, the piezoelectric element 130, will be described below in order.

In the first step, the biometric information recognizing device determines one or more of the plurality of piezoelectric elements 130 and sets them as the signal generating element 131. (Step 1) The signal generating element 131 means a piezoelectric element 130 for generating an ultrasonic signal. The controller 150 applies an electrical signal or a pulse signal to a specific piezoelectric element 130, The element 130 may be caused to vibrate so that the ultrasonic signal is emitted. At this time, the size of the ultrasound signal may vary depending on the size of the electrical signal applied to the signal generating element 131. The control unit 150 may internally store individual identifiers for the piezoelectric elements 130 present on the substrate 110. The controller 150 may control the piezoelectric elements 130 at any particular position to be a signal generating element 131), it can be set and activated by applying an electrical signal based on the identifier of the corresponding piezoelectric element 130.

The biometric information recognizing device sets one or two or more of the piezoelectric elements 130 other than the previously set signal generating element 131 to the signal receiving element 133 in the second step. (Step 2) The signal receiving element 133 functions to receive a reflected wave reflected by the biological tissue of the user and returned by the ultrasonic signal generated by the signal generating element 131. At this time, the biometric information recognizing device preferably sets the piezoelectric element 130 closest to the signal generating element 131 to the signal receiving element 133. This can reduce the energy loss of the ultrasonic signal in the air So as to receive the reflected wave signal more clearly. When the signal generating element 131 is a specific one of the piezoelectric elements 130, the piezoelectric elements 130 existing in the upper, lower, left, and right positions of the signal generating element 131 are set as the signal receiving element 133, . The controller 150 controls the piezoelectric elements 130 located at an arbitrary position to the signal receiving element 133 regardless of the degree of proximity to the signal generating element 131. [ As shown in FIG.

Steps 3 and 4 are steps of activating the previously set signal generating element 131 and signal receiving element 133, respectively, so as to be driven according to respective functions. Specifically, the biometric information recognizing device activates the signal generating element 131 to generate an ultrasonic signal, and activates the signal receiving element 133 to receive the reflected wave signal.

5 illustrates a preferred embodiment of a method of activating the piezoelectric element 130 according to the present invention. In order to recognize a user's biometric information, a signal generating element 131 arranged in a plurality of rows and a plurality of columns, It can be seen that the signal receiving element 133 is activated.

FIGS. 6 and 7 illustrate the process of FIG. 4 and FIG. 5 proceeding in a time-wise manner along a row or a column.

The bio-information recognition device sets a new signal generation element 131 as any one of the plurality of piezoelectric elements 130 adjacent to the signal generation element 131. In this case, (Step 5) At this time, the new signal generating element 131 is selected among the piezoelectric elements 130 existing close to the signal generating element 131 set in the first step. For example, in the new signal generating element 131 set in step 5, any one of the piezoelectric elements 130 existing on the upper side, the lower side, the left side, or the right side of the signal generating element 131 set in step 1 can be set have.

On the other hand, the directionality of the signal generating element 131 newly set in step 5 is also related to the scanning direction. That is, when the newly set signal generating element 131 is set to the piezoelectric element 130 on the right side of the conventional signal generating element 131, the scanning direction becomes the right direction, and the newly set signal generating element 131 When the piezoelectric element 130 is set as the lower side of the conventional signal generating element 131, the scanning direction is the downward direction.

Step 6 is a step of newly setting the signal receiving element 133 in accordance with the new signal generating element 131 set in step 5 by the biometric information recognizing apparatus. Step 6 proceeds in a manner similar to that in which the signal receiving element 133 is set in step 2. [

It should be noted that the signal receiving element 133 set in this step may be overlapped with the signal receiving element 133 set in the second step. 7, when the signal generating element 131 is set to move to the right, the signal receiving element 133 corresponding to the signal generating element 131 moves to the right along the signal generating element 131. At this time, There may be some overlapping piezoelectric elements 130, i.e., the signal receiving element 133. [

Finally, steps 7 and 8 are the steps of activating the newly set signal generating element 131 and the signal receiving element 133 to perform functions of ultrasonic wave generation and reflection wave reception, respectively.

The method of activating the piezoelectric element 130 according to the present invention is performed by repeating the steps 1 to 8, preferably by setting and activating the signal generating element 131 from one end to the end of a specific row or a specific column Is repeatedly performed. Therefore, when the user places the finger on the biometric information recognizing device, the biometric information recognizing device sets the signal generating device 131 in one row or a plurality of rows, sets and activates the signal receiving device 133, 130 to generate ultrasonic waves and receive reflected waves, and obtain biometric information such as fingerprint, blood vessel, and bone shape of the user using the received reflected wave signal. In order to facilitate the understanding of the present invention, the present invention will be described in terms of the first to fourth steps as one cycle, the fifth to eighth steps as two cycles, the next cycle of the first to fourth cycles as three cycles, do.

Meanwhile, the biometric information recognizing apparatus according to the present invention can adjust the magnitude of the ultrasonic signal generated in the car turning according to the magnitude of the reflected wave signal received at the previous turn. Fig. 8 is a view for explaining this characteristic of the present invention.

In general, the user's finger in contact with the biometric information recognizing device is streamlined, and the biometric information recognizing device has a face contacting the finger and a face contacting the finger. Thus, The same amount of power is consumed for the elements 130 and does not need to be activated. That is, if the surface on which the finger is touched can be distinguished on the biometric information recognizing device, only the piezoelectric elements 130 corresponding to the touched surface can be activated, thereby reducing power consumption.

Referring to FIG. 8, the biometric information recognizing apparatus according to the present invention starts scanning the biometric information by generating an ultrasonic signal at a predetermined size when setting and activating the first signal generating element 131, and when a reflected wave signal is received Or when a signal size of a predetermined size or less is received, the size of the ultrasonic signal generated in the next rotation, i.e., the second rotation, is maintained at the same magnitude as in the previous rotation, And when it is received in excess, amplifies the size of the ultrasonic signal generated in the next rotation and outputs the amplified signal.

9 shows another embodiment in which the size of the ultrasonic signal generated by the biometric information recognizing device is adjusted.

The biometric information recognizing device compares the magnitude of the reflected wave received at the first round with the magnitude of the received reflected wave at the second round, and when the difference exceeds the reference value, the ultrasonic wave generated by the newly generated signal generating element 131 The size of the signal can be adjusted. For example, when the magnitude of the reflected wave received at the second rotation is larger than the magnitude of the reflected wave received at the first rotation, and the difference is larger than the reference value, this is because the user's finger starts to come into close contact with the biometric information recognition device. The size of the ultrasonic wave to be generated can be amplified. On the contrary, when the magnitude of the reflected wave received at the present rotation is smaller than the magnitude of the reflected wave received at the rotation rotation, and the difference is larger than the reference value, it is considered that the finger rotation is close to the biometric information recognition device. The size of the ultrasonic waves to be desired can be reduced.

The configuration of the biometric information recognizing apparatus according to the present invention and a method of scanning the biometric information of the user using the corresponding apparatus, that is, various methods for selectively activating a plurality of piezoelectric elements have been described with reference to the drawings.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention.

110 substrate
130 Piezoelectric element 131 Signal generating element 133 Signal receiving element
150 control unit
300 cover substrate

Claims (10)

A method for selectively activating a piezoelectric element in a biological information recognition apparatus,
(a) setting a specific one of the plurality of piezoelectric elements as a signal generating element;
(b) setting at least one piezoelectric element among the piezoelectric elements other than the signal generating element as a signal receiving element;
(c) activating the signal generating element to generate an ultrasonic signal;
(d) activating the signal receiving element to receive the reflected wave signal, wherein the reflected wave signal is reflected by the living tissue by the ultrasonic signal generated by the signal generating element;
Lt; / RTI >
Wherein the plurality of piezoelectric elements are arranged in a matrix form having a plurality of rows and a plurality of columns,
Wherein the step (b) comprises setting at least one piezoelectric element close to the signal generating element as a signal receiving element,
After step (d)
(E) setting any one of a plurality of piezoelectric elements existing on the upper side, the lower side, the left side, or the right side of the signal generation element as a new signal generation element,

After step (d)
(F) setting at least one piezoelectric element in proximity to the new signal generating element to a new signal receiving element;
(G) generating an ultrasonic signal by activating a newly set signal generating element in the step (e);
Wherein the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue in the step (h), wherein the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue after receiving the reflected wave signal by activating the newly set signal receiving element in the step (f) ;
Further comprising:

The biometric information recognizing device comprises:
(a) to (h) are repeated,
The signal generating elements set in the steps (a) and (e) are piezoelectric elements arranged on one row or column or arranged diagonally to each other.

The biometric information recognizing device comprises:
compares the magnitudes of the received reflected wave signals in steps (d) and (h)
When the size difference of the reflected wave exceeds the reference value, amplifies the size of the ultrasonic signal generated by the signal generating element newly set next time
/ RTI >



delete delete delete delete The method according to claim 1,
The plurality of piezoelectric elements are given a unique identifier,
Wherein the biometric information recognizing device sets and activates the signal generating element and the signal receiving element based on the unique identifier.
The method according to claim 1,
The biometric information recognizing device comprises:
measures the size of the received reflected wave signal in step (d)
Wherein the size of the ultrasonic signal generated in the step (g) is adjusted according to the magnitude of the reflected wave signal.
delete The method according to claim 1,
Wherein the living body tissue is at least one of a fingerprint, a blood vessel, and a bone.
Board;
A plurality of piezoelectric elements arranged on the substrate in a matrix form having a plurality of rows and a plurality of columns;
A controller selectively activating the plurality of piezoelectric elements;
, ≪ / RTI &
The control unit
Setting a specific piezoelectric element among the plurality of piezoelectric elements as a signal generating element and setting at least one of the piezoelectric elements other than the signal generating element as a signal receiving element,
Wherein the signal generating element is activated to generate an ultrasonic signal, and the signal receiving element is activated to receive a reflected wave signal, wherein the reflected ultrasonic signal is reflected by the living tissue,
And the control unit sets any one of the plurality of piezoelectric elements existing on the upper side, the lower side, the left side or the right side of the signal generation element as a new signal generation element after the signal receiving element receives the reflected wave signal In addition,
After receiving the reflected wave signal by activating the signal receiving element,
Characterized in that at least one piezoelectric element adjacent to the new signal generating element is set as a new signal receiving element,

An ultrasonic signal is generated by activating a newly set signal generating element,
And the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue, wherein the ultrasonic signal generated by the newly generated signal generating element is reflected by the living tissue,

The newly formed signal generating elements are piezoelectric elements arranged on one row or column or arranged diagonally to each other,

And the magnitude of the ultrasonic signal generated by the signal generating element newly set next time is amplified when the size difference of the reflected wave exceeds the reference value. Biometric information recognition device.

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