KR100358708B1 - Three-dimensional biometrics security system using interference of light - Google Patents

Abstract

The present invention relates to a three-dimensional biometric security system using an interference structure of light. The present invention, the high power LED 10 for generating a light source; An optical fiber coupler (20) for distributing or coupling the light sources generated from the high power LED (10); The first lens 41 and the second lens 42 which receive a light source from the optical fiber coupler 20 and focus the light source to the living body 50 to output the reflected light reflected from the living body 50 to the optical fiber coupler 20. And an XY translator 43 configured to scan a predetermined portion of the living body; An optical path reference length mm class converter 60 which receives the light source from the optical fiber coupler 20 and periodically changes the optical path reference length of the input light source to mm, and outputs it to the optical fiber coupler 20 again; A photo detector (70) for detecting the coupled light output from the optical fiber coupler (20) and converting the light into an electrical signal; And extracting information of the living body 50 by analyzing the frequency and magnitude of the electrical signal output from the photo detector 70, and comparing the extracted 3D information with the reference information with the reference information to confirm whether the user is present. It consists of 80 to obtain three-dimensional information such as height information and image information of the living body using the interference of light. Therefore, according to the present invention, by obtaining three-dimensional information about the living body can improve the accuracy, safety of the biometric security system and improve the durability of the system.

Description

Three-dimensional biometrics security system using interference of light}

The present invention relates to a three-dimensional biometric security system using an interference structure of light, and more particularly, to a security system for performing biometrics using an optical sensor that can extract the three-dimensional information of the living body.

Biometrics is a technology that identifies individuals by automatically measuring the physical characteristics of humans such as fingerprints, irises, and veins, and replaces existing passwords or cards as the need for accurate identification of users increases due to the proliferation of computer usage and electronic commerce. It has been developed as a means, and currently, a fingerprint mouse, a fingerprint keyboard and monitor, an iris recognition system, and a vein recognition system have been developed.

In particular, the fingerprint (Fingerprint) is a form of a constant flow by the sweat glands are raised, each type is different from each other, and because of the unique characteristics that do not change for life as it is at birth, retina, iris, Not only is it higher than blood vessel, face, voice recognition, etc., it is evaluated as the most practical and compatible field among the biometric fields, and is used as an efficient personal authentication method.

As shown in FIG. 1, the conventional biometric system can be classified into a method of acquiring a fingerprint image using optical and a method of acquiring a fingerprint image using non-optical technology. It is characterized by strong, no corrosion, strong against external shocks and low maintenance costs. The non-optical method has low cost but is weak against static electricity, scratches and external shocks and cannot be maintained, so it must be disposed of.

However, most of these optical or non-optical sensing methods extract two-dimensional images of a living body through a camera or a semiconductor fingerprint sensor, and extract a digital signal corresponding to the two-dimensional images, thereby extracting the characteristic of the extracted fingerprint. Compared with the standard information, the data is verified to identify the identity, so there is a disadvantage in that the other person can be mistaken.

Therefore, the present invention has been proposed to solve the problems of the prior art, an object of the present invention by using the interference structure of light that can change the optical path reference length of the light to mm class and the degree of bending information of the living body and the image Acquiring three-dimensional information about the living body such as information, improving the accuracy and safety of the biological information through the three-dimensional information, and at the same time, using the interference structure of light that can improve the durability of the system through the non-contact method to the living body. It is to provide a biometric security system.

FIG. 1A is a diagram illustrating obtaining a fingerprint image using optical technology, and FIG. 1B is a diagram illustrating obtaining a fingerprint image using semiconductor technology.

2 is a view showing the overall configuration of a three-dimensional biometric security system using an interference structure of light according to the present invention.

3 is an overall flowchart of a three-dimensional biometric security method using the interference structure of light according to the present invention.

4 is a view for explaining the periodic change in the optical path reference length of the light source input by the optical path reference length mm class converter 60 of the present invention in mm class.

Explanation of symbols on the main parts of the drawings

10: high power LED 20: fiber optic coupler

40: translator set 41: first lens

42: second lens 43: X-Y translator

50: living body 60: optical path reference length mm class transducer

61: third lens 62: rotating cube

63: reflector 70: light detector

80: computer

In order to achieve the above object, the present invention, a high power LED for generating a light source; An optical fiber coupler for distributing or coupling the light sources generated from the high power LED; A translator set including a first lens and a second lens configured to receive a light source from the optical fiber coupler and focus the light onto a living body and output the reflected light reflected from the living body to the optical fiber coupler; An optical path reference length mm-class converter that receives the light source from the optical fiber coupler and periodically changes the optical path reference length of the input light source to mm class and outputs the optical path reference length to the optical fiber coupler again; A photo detector detecting the coupled light output from the optical fiber coupler and converting the light into an electrical signal; And a computer which analyzes the frequency and magnitude of the electrical signal output from the photo detector, extracts the information of the living body, and compares the extracted three-dimensional information and the reference information with a computer to check whether the user is present. It is characterized in that to obtain three-dimensional information such as height information and image information.

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

2 is a view showing the overall configuration of a three-dimensional biometric security system using an interference structure of light according to the present invention, Figure 3 is a general flow diagram of a three-dimensional biometric security method using an interference structure of light according to the present invention. 4 is a view for explaining periodically changing the optical path reference length of the input light source to mm class by the optical path reference length mm converter 60 of the present invention.

As shown in FIG. 2, the three-dimensional biometric security system using the interference structure of light of the present invention includes a high power LED 10, an optical fiber coupler 20, a first lens 41, and a second lens 42. Translator set 40 composed of XY translators 43, optical path reference length mm grade transducer 60 composed of third lens 61, rotating cube 62 and reflecting mirror 63, photodetector 70 and A computer 80 is provided. Here, the high power LED 10 can be replaced with another configuration if it can generate the characteristics of the high power LED light source, the optical fiber coupler 20 is to distribute and couple the light source when the transmission line of the light source is not optical fiber. Can be replaced by an optical power splitter.

In FIG. 3, when the light source is emitted from the high power LED 10 (S100), the emitted light source is distributed by the optical fiber coupler 20, and the light distributed through the optical fiber coupler 20 is each a translator set 40. The first lens 41 and the optical path reference length are input to the third lens 61 of the mm-class transducer 60 (S110).

When the XY translator 43 is assumed to be stationary, the first lens 41 of the translator set 40 emits the input light source as parallel light (S121), and the second lens 42 emits the parallel light as a living body. Focusing to 50 (S122). The light formed on the living body 50 is partially reflected to be reflected (S123) in the same manner as the incident path. The reflected light reflected from the living body 50 passes through the second lens 42 and passes through the first lens 41. Output to the optical fiber coupler 20 (S124).

To continuously acquire information on a specific portion of the living body 50, the translator set 40 composed of the first lens 41, the second lens 42, and the XY translator 43 causes the living body 50 to be transferred. Just move it to scan.

At the same time, the third lens 61 of the optical path reference length mm class transducer 60 emits the input light source as parallel light (S125), and the light emitted by the parallel light rotates at a constant speed on the rotating plate. It is inputted by 62. As the rotating cube 62 rotates as shown in FIG. 4, the angle θ between the incident light source and the normal to the plane of the rotating cube 62 is changed, and thus the optical path reference length path of the incident light depends on θ. It becomes nonlinear. The change period of the optical path reference length corresponds to 1/8 of the rotation period of the rotation cube 62. When the material of the rotation cube 62 is glass, the change amount of the optical path reference length is equal to the length of one side of the rotation cube 62. Since it corresponds to about 1/3, if the length of one side of the rotating cube 62 is about 2cm, the optical path reference length can be easily changed to mm class. Therefore, the optical path reference length of the light source input by the rotating cube 62 rotating at a constant speed on the rotating plate is periodically changed to mm class (S126). Light output from the rotating cube 62 is input to the reflecting mirror 63 and reflected by the reflecting mirror 63 and then input to the rotating cube 62 again (S127), and again by the rotation of the rotating cube 62 After the optical path reference length of the light is changed to mm level (S128), the light is output to the optical fiber coupler 20 through the third lens 61 (S129).

Therefore, the reflected light in the living body 50 and the reference light whose optical path reference length is changed to mm class can be obtained by step S120 composed of these steps S121 to S129, respectively.

The reflected light and the reference light obtained from the step S120 and output to the optical fiber coupler 20 respectively interfere with each other at the output end of the optical fiber coupler 20 (S130), in particular, the optical path length of the reflected light from the living body 50 is When the optical path of the reference light is the same as the reference length, that is, the maximum interference occurs at a specific rotation angle θ. Since the optical path reference length of the reference light changes nonlinearly with the rotation of the rotating cube 62, the optical fiber coupler 20 obtains a sinusoidal interference pattern having a different frequency and amplitude depending on the rotation angle θ. The interference pattern is expressed in the form of a sine wave whose frequency and amplitude are different according to the height of the living body, and holds the height information of a certain part of the living body.

After the photodetector 70 detects the interfering light and converts it into an electrical signal (S140), the computer 80 analyzes the frequency and magnitude of the electrical signal output from the photodetector 70 to raise and lower the living body 50. Information is extracted (S150). In addition, the computer 80 scans the translator set 40 and checks the identity by comparing the three-dimensional information obtained by repeating the above process and the stored reference information (S160).

The optical path reference length mm class transducer 60 of the present invention uses a method of changing the optical path reference length of light to mm class by the rotation of the rotating cube 62, but if necessary, The method of changing the path reference length, for example, by removing the rotating cube 62 from the reference arm portion of the Michelson interferometer and changing the optical path reference length by changing the optical fiber length of the reference arm Height information of the living body can be obtained.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

Therefore, according to the present invention, since three-dimensional information about a living body can be obtained by using an interference structure of light capable of changing the optical path reference length in mm, the three-dimensional information such as height information and image information of the living body can be obtained. The accuracy and safety of biometric security systems can be improved.

In addition, according to the present invention, since the non-contact method for the living body is used, the durability of the system can be improved as compared to the existing biometric security system using the direct contact method, and the optical path standard length is continuously converted to mm class. The technology can be applied to other optical applications such as measuring the length and thickness of transparent objects, thereby promoting the vitalization of the optics industry.

Claims (4)

In the security system that automatically measures the physical characteristics of humans to identify individuals, A high power LED 10 generating a light source; An optical fiber coupler (20) for distributing or coupling the light sources generated from the high power LED (10); The first lens 41 and the second lens 42 which receive a light source from the optical fiber coupler 20 and focus the light source to the living body 50 to output the reflected light reflected from the living body 50 to the optical fiber coupler 20. And an XY translator 43 configured to scan a predetermined portion of the living body; An optical path reference length mm class converter 60 which receives the light source from the optical fiber coupler 20 and periodically changes the optical path reference length of the input light source to mm, and outputs it to the optical fiber coupler 20 again; A photo detector (70) for detecting the coupled light output from the optical fiber coupler (20) and converting the light into an electrical signal; And A computer that checks the identity of the user by analyzing the frequency and magnitude of the electrical signal output from the photodetector 70, extracting information of the living body 50, and comparing the extracted three-dimensional information with the reference information. 80) 3D biometric security system using the interference structure of light, characterized in that to obtain three-dimensional information such as height information and image information of the living body using the interference of light. The optical fiber coupler (20) of claim 1, wherein the optical fiber coupler (20) is replaced with an optical power distributor that can distribute the light source generated from the high power LED (10) or couple the returned light source when the transmission line of the light source is not an optical fiber. 3D biometric security system using the interference structure of light, characterized in that. According to claim 1, wherein the optical path reference length mm class transducer 60, A third lens 61 emitting an input light source as parallel light; A rotating cube 62 rotatably installed at the rear of the third lens 61 and periodically changing an optical path reference length of the input light in mm class; And The interference structure of the light, which is installed at the rear of the third lens 61 and comprises a reflector 63 reflecting the light input from the rotating cube 62 and outputting the light to the rotating cube 62. 3D biometric security system. The method of claim 1, wherein the optical path reference length mm class transducer 60 is characterized in that it can be replaced by another method that can change the optical path reference length of the reference arm in the Michelson interferometer 3D biometric security system using light interference structure.