WO2019198871A1

WO2019198871A1 - Portable optical fingerprint input device connected to mobile terminal when used

Info

Publication number: WO2019198871A1
Application number: PCT/KR2018/005778
Authority: WO
Inventors: 백영현; 신요식
Original assignee: 주식회사 유니온커뮤니티
Priority date: 2018-04-13
Filing date: 2018-05-21
Publication date: 2019-10-17
Also published as: KR102118961B1; KR20190119816A

Abstract

Disclosed is a portable optical fingerprint input device connected to a mobile terminal when used. The fingerprint input device of the present invention has a minimized size by using a flat-shaped optical refractor. Nonetheless, the fingerprint input device includes all the elements required for an optical fingerprint authentication and stores a template of a fingerprint registered in an internal memory, and thus has achieved enhanced personal information security.

Description

Portable Optical Fingerprint Input Device Connected to Mobile Terminal

The present invention relates to a small portable optical fingerprint input device that is connected to a mobile terminal of a user such as a smartphone or a tablet and is enhanced in security.

Fingerprint recognition as a personal authentication means is still widely used and the most generalized authentication means compared to other means because it presents a simple structure and counterfeit fingerprint defense performance. A popular method for acquiring fingerprint information is an optical method using an optical refractor such as a prism.

In the conventional optical fingerprint input device, as shown in FIG. 1, an image of a light source 1 for irradiating fingerprint recognition light, a prism 3 to which a finger contacts, and a fingerprint image emitted from the prism 3 are formed. Lens 4 and an image sensor 5 for converting the fingerprint image formed on the lens 4 into an electrical signal. The optical fingerprint input device includes a scattering device and an absorption device according to the arrangement of the prism 3 and the light source 1.

The light emitted from the light source 1 is imaged in the fingerprint pattern while being reflected, absorbed or scattered from the valleys and ridges of the fingerprint incident on the prism 3 and contacting the fingerprint contact surface 3a of the prism 3. It exits again through the exit surface 3b of (). The fingerprint image emitted from the prism 3 is imaged on the image sensor 5 through the lens 4 to generate a digital fingerprint image.

Since optical fingerprint authentication uses an optical refractor, it is recognized that there is a limit in miniaturization. Since the prism 3 has a triangular cross section and changes the optical path to a certain angle or more, the fingerprint input device using the prism 3 has a larger volume than the semiconductor type or the like by any method. to be.

There are other personal authentication methods that replace optical fingerprint authentication. For example, in recent mobile terminals such as smartphones or tablets, passwords are still used or face recognition using a camera is generally inconvenient. Among the fingerprint authentication methods, the semiconductor method has an advantage of reducing the size, but there is a limit in performance in detecting a forged fingerprint.

In recent years, mobile terminals have become a device that most people carry, and have a tendency to have various sensors and functions. One of the most important is the means of personal authentication. For the quality of personal authentication itself, optical is appropriate, but the limitation of miniaturization must be overcome.

Alternatively, referring to Korean Patent Laid-Open Publication No. 2005-90884, Secutronics discloses a fingerprint input device having a relatively thin thickness by using a plate-shaped optical refractor that is not triangular. The fingerprint input device arranges a light source on the side of the optical refractor to obtain a fingerprint image by using the light scattered in the optical refractor. The device has achieved a thin fingerprint input device as a whole by using a thin optical refractor.

However, referring to the Secutronics invention (FIG. 13 and its description, etc.), it can be seen that the fingerprint input device proposed by the present invention is still implemented by a method embedded in a mobile device. When the fingerprint input device is embedded in the terminal, the thickness of the terminal may be larger than a predetermined size by the fingerprint input device. Therefore, this method does not meet the tendency of thinning of mobile terminals in recent years, and of course, there is a problem that cannot be used in a mobile terminal that is produced and used.

Applicant has registered a patent on a fingerprint recognition device of the type external to a mobile terminal. The external fingerprint recognition device according to the present invention is a fingerprint recognition device using a light and a camera built in a mobile terminal instead of an optical refractor and a lens, instead of a light and an image sensor. Since part of the configuration of the fingerprint recognition device uses a mobile terminal, the external fingerprint recognition device can be miniaturized.

On the other hand, the payment of life insurance, etc., because the contractor and the insured must be different from each other, according to the 'cinnamon contract.' The problem is that the contractor's certificate is required when paying the insurance benefits due to the contractor's death. Since the contractor is dead, other authentication means, such as iris and face recognition, are difficult to authenticate. In this case, personal authentication is more important for security, so it is necessary to prevent unauthorized access to read a registered fingerprint or hack an authentication record.

[Related Technical Documents]

1. Optical fingerprint input device for mobile devices (Korean Patent Publication No. 2005-90884)

2. Fingerprint input device using a mobile terminal equipped with a camera and external optical device for fingerprint input thereof (Korean Patent Nos.1493332, 1479609)

SUMMARY OF THE INVENTION An object of the present invention is to provide a portable optical fingerprint input device with a thin thickness which is connected to a mobile device of a user such as a smartphone or a tablet and has enhanced security.

According to an aspect of the present invention, there is provided a portable optical fingerprint input device comprising: an optical unit including an optical refractor and a light source to generate and output a fingerprint image of a fingerprint in contact with a fingerprint contact surface of the optical refractor; And a circuit unit configured to receive a fingerprint image from the optical unit, generate a fingerprint image, and perform user authentication. Here, the circuit unit includes an image sensor, a memory, a communication interface, and a controller. The image sensor receives a fingerprint image from the optical unit to generate a fingerprint image, and the fingerprint templates of a plurality of registered fingerprints are stored in the memory. The communication interface communicates with the mobile terminal by wire and receives power from the mobile terminal. The control unit operates the optical unit according to the authentication request for the first user of the mobile terminal, performs authentication by comparing the fingerprint image generated by the image sensor with a template of the first user registered in the memory. Notify the mobile terminal of the authentication result.

According to an embodiment of the present disclosure, the optical unit may include a flat optical refractor including a fingerprint contact surface on an upper surface and an emission surface on which the fingerprint image is emitted on a front surface connected to the upper surface; A plurality of light sources disposed below the optical refractor at regular intervals to irradiate light for fingerprint input to the fingerprint contact surface through a lower surface of the optical refractor; A lens provided between the exit surface and the image sensor to form the fingerprint image with the image sensor; And a first mirror disposed between the lens and the image sensor to reflect the image sensor in parallel with the fingerprint contact surface to reflect the fingerprint image passing through the lens to the image sensor.

In addition, the optical refraction unit, the fingerprint contact surface for converting the light emitted from the light source to the fingerprint image while being scattered and reflected by the contact fingerprint, and the emission surface disposed on the front surface perpendicular to the fingerprint contact surface, A light incidence surface disposed on a lower surface facing the plurality of light sources and emitted from the plurality of light sources, the light incidence surface totally reflecting the fingerprint image converted from the fingerprint contact surface, and an inclination so as to form an internal angle with the light incidence surface It is preferably provided with a back side, wherein the inside angle is preferably set to an angle capable of totally reflecting the fingerprint image totally reflected from the light incident surface toward the exit surface.

According to another embodiment, the communication interface is a USB (Universal Serial Bus) or RS-232 serial communication interface, and may include a connection terminal to which a cable connecting the mobile terminal is connected.

The plurality of light sources of the present invention according to another embodiment is to expose the color through the fingerprint contact surface using a blue, red or green LED. In addition, the light source is the power supply through the communication interface to start the operation, when receiving the authentication start command from the mobile terminal to receive the fingerprint input, and proceeds authentication according to the authentication start command, the authentication success or authentication When the failure is determined, the operation state may be displayed without having a separate display unit by being turned on and off in a predetermined specific pattern at at least one selected time point.

Fingerprint input device of the present invention is easy to carry the user by minimizing the overall size and thickness by using a flat-shaped optical refractor, fingerprint registration, fingerprint authentication only when receiving a predetermined control command connected to a mobile terminal such as a user's tablet Security is enhanced by performing

Although the fingerprint input device of the present invention has a smaller overall size, the fingerprint input device can obtain a fingerprint image having a size sufficient to secure a feature point by maximizing the fingerprint input surface.

In addition, even though the fingerprint input device of the present invention is reduced in size, all the components necessary for optical fingerprint authentication are built in such that information or images related to the input fingerprint are not leaked to the outside during the fingerprint registration or authentication process. The fingerprint template is encrypted and stored in internal memory for enhanced security.

1 is a conceptual diagram provided to explain a conventional optical fingerprint input method;

2 is a perspective view of a fingerprint input device of the present invention connected to a mobile terminal;

3 is a block diagram of a fingerprint input device of the present invention, and

4 is a cross-sectional view provided for explaining a fingerprint image generation process of the fingerprint input device of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

2 to 4, the fingerprint input apparatus 200 of the present invention obtains a fingerprint image from a user fingerprint in contact with the fingerprint contact surface 211a and registers it as a template, and then registers a fingerprint for the registered user when personal authentication is required. Perform authentication. The fingerprint input device 200 may be connected to the mobile terminal 10, and performs fingerprint registration, fingerprint authentication, etc. under the control of the mobile terminal 10.

The mobile terminal 10 corresponds to terminals that perform a user interface function and connect to an external server on behalf of the fingerprint input device 200 of the present invention, and other principals not related to the fingerprint input of the present invention. It may have a function. Accordingly, the mobile terminal 10 should include display means for displaying an image or text and input means for receiving a user control command. For example, devices called so-called 'tablets' or 'smart phones' It may correspond to the mobile terminal 10 of the present invention. The mobile terminal 10 of FIG. 2 is provided with a touch pad 11 for display means and input means. The mobile terminal 10 should have a communication interface connected to the communication interface 237 of the fingerprint input device 200 described below, and can be supplied with a universal serial bus or RS-232 for data transmission and reception. Etc. are preferable.

The fingerprint input device 200 of the present invention includes an optical unit 210, a circuit unit 230, and a housing 250 to accommodate them. 2, in the housing 250, a fingerprint contact window 251 for inputting a fingerprint by a user is formed on an upper surface thereof, and the connection terminal 237a of the display unit 233 and the communication interface 237 described below. ) Is exposed. Since the size of the fingerprint contact window 251 is smaller than the fingerprint contact surface 211a of the optical refraction machine 211 described below, the area of the fingerprint input at one time by the fingerprint contact window 251 is determined. It should be approximately 15 x 20mm in size for sufficient user authentication. When the communication cable 30 is connected between the connection terminal 237a and the mobile terminal 10 to connect the fingerprint input device 200 with the mobile terminal 10, the fingerprint input device 200 is not supplied with operating power. .

Referring to FIG. 3, the optical unit 210 includes an optical refractor 211, a lens 213, and a first mirror 215, and a user who contacts the fingerprint contact surface 211a of the optical refractor 211. Make a fingerprint image for your fingerprint. The fingerprint image generated by the optical unit 210 is input to the image sensor 231 of the circuit unit 230 to form an image.

The light source 217 irradiates light for generating an optical fingerprint image toward the fingerprint contact surface 211a of the optical refractor 211. As shown in FIG. 2, when the thickness of the photorefractor 211 is thin and the light source 217 is disposed close to the bottom of the photorefractor 211, the light source 217 may be illuminated despite the angle of view of the light source 217. Since the area that can be limited is limited, it is important to arrange the plurality of light sources 217 at regular intervals to illuminate the fingerprint contact surface 211a relatively uniformly.

The image sensor 231 generates a digital fingerprint image from the fingerprint image incident from the photorefractor 211, and the lens 213 forms an image from the exit surface of the photorefractor 211 on the image sensor 231. do. The first mirror 215 is disposed on the optical path between the lens 213 and the image sensor 231 to change the path of the fingerprint image emitted from the optical refractor 211 by a certain angle (for example, 90 °). 231 may be disposed in parallel with the optical refraction machine 211, so that the fingerprint input device 200 may be sufficiently flat and thin.

The lens 213 and the first mirror 215 form an optical path between the emission surface 211b of the optical refractor 211 and the image sensor 231, thereby providing a fingerprint image emitted from the optical refractor 211. Light) is incident on the image sensor 231. Although FIG. 2 shows the lens 213 disposed in front of the first mirror 215, this arrangement is, of course, illustrative, and for example, additional mirrors may be placed before or after the lens 213. A plurality of lenses 213 can also be used as necessary.

The optical refractor 211 may be any kind of optical element including a fingerprint contact surface to which the finger F contacts, a light entrance surface to which light emitted from the light source 217 is incident, and an exit surface to which the fingerprint image is finally emitted. Do. However, the optical refractor 211 may be implemented in a thin flat plate shape so that the fingerprint input device 200 may be sufficiently thin in a plate shape. The size of the fingerprint contact surface of the optical refractor 211 may correspond to or be larger than the fingerprint contact window 251. In addition, for sufficient user authentication, the fingerprint contact surface should preferably have a size of approximately 15 x 20 mm or more.

The optical refractor 211 of FIG. 4 is an example of the optical refractor of the present invention. In the optical refractor 211 of FIG. 4, the fingerprint contact surface 211a is disposed on the 'upper surface', and the emission surface 211b is disposed on the 'front surface' perpendicular to the fingerprint contact surface 211a, and the light incident surface is disposed on the lower surface. It is a board-board shape in which 211c is disposed. The rear surface 211d facing the front surface of the optical refractor 211 forms a light incident surface 211c and an internal angle α having a predetermined size. The arrangement of the cabinet α is for total reflection of the path of the fingerprint image totally reflected in the optical refraction machine 211 to the exit surface 211b as shown in FIG. 4. The path of the fingerprint image in the photorefractor 211 will be described again with reference to the light source 217 below.

The circuit unit 230 includes a light source 217, an image sensor 231, a display unit 233, a memory 235, a communication interface 237, and a controller 239. Since the fingerprint input device 200 receives power from the mobile terminal 10, the fingerprint input device 200 does not need to include a battery or a power supply. The circuit unit 230 is disposed below the flat optical refractor 211 in parallel with the fingerprint contact surface 211a, thereby miniaturizing and optimizing the size of the fingerprint input device 200.

The light source 217 is disposed to face the light incident surface 211c of the light refractor 211, so that light emitted from the light source 217 is directly incident on the light incident surface 211c of the light refractor 211. . By this arrangement, the fingerprint input apparatus 200 of FIG. 2 generates a fingerprint image in a transmissive (ie, scattering) manner. In FIG. 2, the light source 217 is disposed on the lower surface side of the optical refractor 211 so that the lower surface of the optical refractor 211 becomes a light incident surface. Light emitted from the light source 217 is incident on the light incident surface 211c perpendicularly.

Since the light emitted from the light source 217 passes through the light incident surface 211c and is incident on the fingerprint contact surface 211a of the optical refractor 211 at an angle smaller than the critical angle, the fingerprint image contacts the fingerprint contact surface 211a. Formed mainly by light scattered from the ridges of a fingerprint, the valleys are dark and the ridges appear bright, resulting in a good contrast. Referring to FIG. 4, light is scattered or reflected on the fingerprint contact surface 211a and becomes a fingerprint image, and is totally reflected on the light incident surface 211c and the back surface 211d of the optical refractor 211. At this time, the light incident surface 211c and the back surface 211d form an internal angle α so that the fingerprint image totally reflected from the light incident surface 211c can be sufficiently totally reflected toward the exit surface 211b. The fingerprint image emitted from the exit surface 211b is collected through the lens 213, reflected by the first mirror 215, and incident on the image sensor 231.

The image sensor 231 receives a fingerprint image emitted from the exit surface 211b of the optical refractor 211 and passes through the lens 213 to generate a fingerprint image, and stores the fingerprint image in the memory 235 and the controller 239. To provide. Since the image sensor 231 is disposed at an angle of 90 ° with respect to the emission surface 211b, a first mirror 215 is required between the emission surface 211b and the image sensor 231. The input device 200 can be miniaturized.

The display unit 233 is a display unit for displaying the operation state of the fingerprint input apparatus 200 to the user, and may be various forms of display means. For example, in order to miniaturize the fingerprint input device 200, the display unit 233 may be sufficient as one or two LEDs to indicate that the user is requesting to input a fingerprint. However, the display unit 233 is not an essential configuration.

For example, the display unit 233 may be replaced by using a blue, red, or green LED as the light source 217. When the light source 217 is turned on for the fingerprint input, the color of the LED is reflected through the fingerprint contact window 251 so that the user can know that the fingerprint input device 200 is in an operating state. Furthermore, when the power is supplied through the communication interface 237 to start the operation, when the fingerprint registration command or the authentication start command is received from the mobile terminal 10 and the fingerprint is input, the fingerprint registration is completed according to the fingerprint registration command. At a time, and at least one time point selected from when authentication is performed according to the authentication start command to determine authentication success or failure, the control unit 239 sets the blue, red, or green light source 217 in a predetermined pattern. By turning on and off, the operation state can be displayed without providing a separate display unit 233.

The memory 235 stores a fingerprint image generated by the image sensor 231, a template (feature point data) of the fingerprint registered through the fingerprint registration process, authentication history information, and the like. In addition, the fingerprint input device 200 according to the present invention. Various information of is stored. The enrolled fingerprint template and / or fingerprint image stored in the memory 235 are stored to be classified and searched by a certain serial number or the like. The data stored in the memory 235 is preferably encrypted by the controller 239.

The communication interface 237 uses a wired communication interface for supplying power and communicating with the mobile terminal 10. For example, protocols such as USB or RS-232 can be used. The communication interface 237 has a connection terminal 237a exposed at one side of the housing 250.

The controller 239 controls the overall operation of the fingerprint input device 200 of the present invention. The controller 239 first performs a fingerprint registration and authentication process for a specific user (hereinafter referred to as a first user) under the control of the mobile terminal 10, and provides the result to the mobile terminal 10. However, since the fingerprint input device 200 and the mobile terminal 10 are connected to each other through the communication interface 237, the communication interface will be described below even if it is described as if there is direct communication between the control unit 239 and the mobile terminal 10. It should be understood that the transmission and reception by (237).

지문 등록Fingerprint registration

User fingerprint registration is initiated at the request of the mobile terminal 10. When the controller 239 receives the fingerprint registration command from the mobile terminal 10, the controller 239 turns on the light source 217 to start the fingerprint registration process. At this time, the fingerprint registration command of the mobile terminal 10 includes the 'identification code' assigned to the first user to register.

When a fingerprint is input and the light emitted from the light source 217 is changed into a fingerprint image and output through the emission surface 211b, the image sensor 231 converts the fingerprint image into a digital fingerprint image. The controller 239 checks the quality of the fingerprint image and determines whether the fingerprint image is a fake fingerprint. If there is no problem with the quality check and is not a fake fingerprint, the controller 239 generates a fingerprint template by extracting feature points from the fingerprint image, and then maps the 'identification code' included in the fingerprint registration command and stores it in the memory 235. The controller 239 notifies the mobile terminal 10 of the fingerprint registration completion according to the fingerprint registration command together with storing the fingerprint template, thereby completing the fingerprint registration for the first user initiated by the fingerprint registration command. In the process of storing in the memory 235, the control unit 239 can encrypt and store the fingerprint template with a certain encryption code.

If the quality of the fingerprint image is poor or is determined to be a fake fingerprint, the controller 239 may provide the error information to the mobile terminal 10 or display it through the display unit 233, and provide the error information and display unit 233. You can also perform all of the display with). In the fingerprint registration process, it is not necessary to check the quality of ① or judge the fake fingerprint of ②. It can be applied selectively.

사용자 인증User authentication

User authentication is also initiated at the request of the mobile terminal 10. When the controller 239 receives the 'authentication start command' from the mobile terminal 10, the controller 239 turns on the light source 217 to start a user authentication process. At this time, the 'authentication start command' of the mobile terminal 10 includes the 'identification code' of the first user to be authenticated.

When the fingerprint for authentication is input, and the light emitted from the light source 217 is changed to the fingerprint image and the emission surface 211b and the emission surface 211b are emitted, the image sensor 231 converts the fingerprint image into the fingerprint image. For convenience of description, the fingerprint image generated by the image sensor 231 during the authentication process is referred to as a 'fingerprint fingerprint image'.

The controller 239 checks the quality of the fingerprint image for authentication and determines whether the fingerprint image for authentication is a fake fingerprint. If there is no problem with the quality check and is not a fake fingerprint, the control unit 239 extracts the feature point from the fingerprint image for authentication and maps the fingerprint template (ie, the fingerprint template of the first user) to the identification code on the authentication start instruction from the memory 235. ) And compare them for equality.

If the authentication feature point and the fingerprint template extracted from the memory 235 are the same, the controller 239 notifies the mobile terminal 10 of successful authentication, thereby terminating the authentication process for the first user initiated by the authentication start command. If the feature point for authentication and the fingerprint template extracted from the memory 235 are not the same, the controller 239 notifies the mobile terminal 10 of the authentication failure, thereby performing the authentication process for the first user initiated by the authentication start command. Quit.

If the quality of the fingerprint image is poor or is determined to be a fake fingerprint, the controller 239 may provide the error information to the mobile terminal 10 or display it through the display unit 233, and provide the error information and display unit 233. You can also perform all of the display with). In the fingerprint authentication process, it is not necessary to check the quality of ① or judge the fake fingerprint of ②. It can be applied selectively.

In the fingerprint registration process or the fingerprint authentication process, the controller 239 notifies the mobile terminal 10 of fingerprint registration completion, authentication success or authentication failure, and generates a fingerprint template, a fingerprint template for authentication, or a registered fingerprint. The template is not provided to the mobile terminal 10. Therefore, the fingerprint template of the user stored in the fingerprint input device 200 is basically not leaked to the outside. In addition, since the fingerprint template stored in the memory 235 is encrypted, even if the fingerprint template stored in the memory 235 is leaked in the process of loss or the like, the contents cannot be confirmed or modified.

Although the above has been illustrated and described with respect to preferred embodiments of the present invention, the present invention is not limited to the above-described specific embodiments, it is usually in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

Claims

In a portable optical fingerprint input device,

An optical unit for generating and outputting a fingerprint image of the fingerprint in contact with the fingerprint contact surface; And

A circuit unit configured to receive the fingerprint image from the optical unit, generate a fingerprint image, and perform user authentication;

The circuit portion,

An image sensor which receives a fingerprint image from the optical unit and generates a fingerprint image;

A memory in which fingerprint templates of a plurality of registered fingerprints are stored;

A communication interface connected by wire with a mobile terminal and receiving power from the mobile terminal; And

The optical unit is operated according to an authentication start command for the first user of the mobile terminal, the fingerprint image generated by the image sensor is compared with a template of the first user registered in the memory, and the authentication is performed. And a control unit which notifies the terminal of the authentication result.
The method of claim 1,

The optical unit,

A flat optical refractor including a fingerprint contact surface on an upper surface and an emission surface on which a fingerprint image is emitted on a front surface connected to the upper surface;

A plurality of light sources disposed below the optical refractor at regular intervals to irradiate light for fingerprint input through the lower surface of the optical refractor to the fingerprint contact surface;

A lens provided between the exit surface and the image sensor to form the fingerprint image with the image sensor; And

The optical unit includes a first mirror disposed between the lens and the image sensor to reflect the image sensor in parallel with the fingerprint contact surface to reflect the fingerprint image passing through the lens to the image sensor. Portable optical fingerprint input device, characterized in that implemented in a flat plate shape.
The method of claim 1,

The optical refraction machine,

The fingerprint contact surface for converting the light emitted from the light source into the fingerprint image while being scattered and reflected by the contact fingerprint;

The exit surface disposed on a front surface perpendicular to the fingerprint contact surface;

A light incidence surface disposed on a lower surface of the plurality of light sources, the light incident from the plurality of light sources is incident, and totally reflecting a fingerprint image converted from the fingerprint contact surface;

It has a rear surface inclined to form the light incident surface and the inside,

The cabinet is a portable optical fingerprint input device, characterized in that the angle set to the total reflection of the fingerprint image totally reflected from the light incident surface toward the exit surface.
The method of claim 1,

The communication interface is a USB or RS-232 serial communication interface, characterized in that the portable optical fingerprint input device comprising a connection terminal to which the cable connecting the mobile terminal is connected.
The method of claim 1,

The plurality of light sources,

The color is exposed through the fingerprint contact surface using a blue, red or green LED, and when power is supplied through the communication interface to start an operation, the fingerprint is received by receiving an authentication start command from the mobile terminal. And when the authentication is performed according to the authentication start command to determine whether the authentication succeeds or fails, the portable optical fingerprint input device is displayed by turning on and off in a specific pattern at at least one time point selected.