KR20040072822A - Iris recognition system using of spherical cold mirror - Google Patents

Abstract

PURPOSE: An iris recognition system applying a spherical surface typed cold mirror is provided to miniaturize a size of entire optical unit by making a figure of the cold mirror attached to a front surface of an optical system into a spherical surface. CONSTITUTION: The spherical surface typed cold mirror(302) is attached to the front of the optical system(301). The optical system comprises straight LEDs(Light Emitting Diode) measuring that a user approaches in a recognizable distance are place to left/right, a CCD(Charge Coupled Device) detecting the approach of the user in the recognizable distance, lightings turned on in order to capture an image, a column keeping a focal distance in order to capture an iris image, and a lens converging light by passing the light keeping the focal distance in order to adjust a focus.

Description

Iris RECOGNITION SYSTEM USING OF SPHERICAL COLD MIRROR}

The present invention relates to an iris recognition system using a spherical cold mirror, and more particularly, to an iris recognition using a spherical cold mirror capable of miniaturizing the overall optical unit size by making a spherical shape of a cold mirror attached to the front surface of an optical system. It's about the system.

As is known, it is a system for security, crime prevention, and identity authentication. It goes beyond the existing contact or contactless card system to recognize human fingerprints, or to authenticate identity through iris recognition and access to specific places or access to specific information. Systems to allow or deny such have been prevalent.

Among them, the iris recognition system has a high recognition rate and more accurate recognition than the fingerprint recognition. The iris recognition system is a system that authenticates an individual by comparing a characteristic pattern of an iris with an image processing technology in an iris image captured by a video camera and comparing it with previously registered iris data.

FIG. 1 is a diagram schematically illustrating a configuration of a general iris recognition system. Referring to FIG. 1, an operation of an iris recognition system is as follows.

When the user approaches the iris recognition system, the distance measuring sensor 109 measures the distance to the user, and the controller 105 receives the distance measurement value obtained through the driver 107 to operate the distance measurement value. Determine if you are in range.

If the user is within the operating range, a control signal is sent to the driver 107 to prepare to extract the iris image. The driver 107 sends an active signal to the external indicator 108 to inform the user that the system is operating. Accordingly, when the user places the eye on the optical axis of the camera 103 through the optical window 101, the cold mirror ( 102 blocks visible light and passes infrared light. In addition, the part where the iris should be positioned is displayed so that the user can check whether the eye is located on the optical axis of the camera 103.

Then, the controller 105 receives the distance measurement value from the distance measurement sensor 109 to the user, and calculates the zoom and focus values of the camera 103 by using the distance measurement value to perform zoom in / zoom out and focusing control. Perform. Thereafter, the controller 105 allows the driver 107 to capture the iris image according to the distance measurement value, and the photographed iris image is signal-processed in the frame grabber 104 for iris image analysis, and the processed iris is processed. The image information is stored in the DB 110 (database), and with the stored information, the control device 105 performs iris recognition to determine whether the user is authenticated.

On the other hand, in such an iris recognition system, the performance depends on how fast and how accurately the iris recognition is performed. Moreover, in the general iris recognition system of this technical field, the user may approach the iris recognition system, and may cause a problem as to whether the iris is correctly positioned on the optical axis of the camera. Ensure accurate iris recognition.

2 is a view schematically showing the external structure of an optical unit according to the related art. As shown therein, an optical system 201 having a lens and a CCD for performing iris recognition and registration; And a flat cold mirror 202 mounted to the front of the optical system 201 with the lens and CCD.

The area of the flat cold mirror 202 mounted as described above has a size larger than the area of the front surface of the optical system 201 having the lens and the CCD in consideration of the eye size of the user.

However, this causes a problem of high processing cost and the size of the overall optical unit.

The present invention relates to an iris recognition system to which a spherical cold mirror is applied. In particular, the iris is applied to a spherical cold mirror capable of miniaturizing the overall size of an optical unit by using a spherical shape of a cold mirror attached to a front surface of an optical system. The purpose is to provide a recognition system.

1 is a view schematically showing the configuration of a general iris recognition system.

Figure 2 schematically shows the external structure of the optical unit according to the prior art.

3 schematically illustrates the structure of an optical unit according to the invention;

4 shows schematically an internal configuration of an optical system according to the invention.

<Description of the symbols for the main parts of the drawings>

301 --- Optical System 302 --- Spherical Cold Mirror

In order to achieve the above object, the iris recognition system applying the spherical cold mirror according to the present invention,

An optical system having a lens and a CCD for performing iris recognition and registration;

It is characterized in that it comprises a spherical cold mirror mounted on the front of the optical system with the lens and CCD.

Here, in particular, the spherical cold mirror is characterized in that it has a size similar to that of the optical system with the lens and CCD.

In particular, the spherical cold mirror is characterized in that it has a predetermined horizontal magnification.

The present invention relates to an iris recognition system to which a spherical cold mirror is applied. In particular, the overall size of the optical unit can be miniaturized by using a spherical shape of the cold mirror attached to the front surface of the optical system.

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

3 is a view schematically showing the structure of an optical unit according to the present invention. As shown therein, an optical system 301 having a lens and a CCD for performing iris recognition and registration; And a spherical cold mirror 302 mounted to the front of the optical system 301 with the lens and CCD.

4 is a view schematically showing an internal configuration of an optical system according to the present invention.

As shown therein, when approaching the iris recognition system, the left and right straight LEDs 401 and 402 are disposed to measure whether the iris recognition system is approached within a recognizable distance; A charge coupled device (CCD) 405 for detecting an access within a recognition distance of the user; Illuminations 403 and 404 that light up to capture an image; A barrel 406 for maintaining a focal length to capture an iris image; It is composed of a lens 407 for converging the light to pass through the light maintained the focal length to form a focus.

When light is emitted by the straight LEDs 401 and 402, the CCD 405 detects whether the CCD 405 approaches the recognition distance. The lights 403 and 404 are turned on to capture the iris image, and are turned on while changing the illumination depending on whether the image is reflected to focus the image.

The barrel 406 is provided with the lens 407 to maintain a predetermined length, which is to maintain the focal length at a certain distance, the actual focal length at a predetermined magnification with the object based on the focal length. Get to know.

Therefore, a predetermined magnification value of the length between the barrel 406 and the lens 407 becomes a focal length with the actual object, and as the length thereof changes, the actual focal length also changes.

In addition, when the user approaches the recognition distance and the focus distance is too close to focus, a transparent slit or the like is inserted in consideration of the focus distance at the position to increase the focus.

On the other hand, the spherical cold mirror 302 has a curvature within a range that does not affect the optical system 301, and has the characteristics of a spherical mirror.

In general, in a spherical mirror, the ratio of the lateral size of the formed final image and the size of the corresponding object is called a transverse magnification M _T , and M _T = the lateral size of the object / imaged final image.

That is, in the case of the conventional flat cold mirror, the size of the final image formed with the size of the object is maintained at 1: 1, but in the case of the spherical cold mirror having the characteristics of the spherical mirror, the size of the object (eye size of the user) It is possible to adjust the size of the formed final image (the user's own eye reflected in the cold miller) corresponding to.

Therefore, it is possible to reduce the size of the flat cold mirror according to the prior art and to reduce the overall size of the optical unit.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the iris recognition system using the spherical cold mirror according to the present invention can reduce the size of the overall optical unit by making the spherical shape of the cold mirror attached to the front surface of the optical system as a spherical surface.

Claims (3)

An optical system having a lens and a CCD for performing iris recognition and registration; And a spherical cold mirror mounted on a front surface of the optical system including the lens and the CCD. The method of claim 1, The spherical cold mirror is an iris recognition system using a spherical cold mirror, characterized in that having a size similar to the size of the optical system. The method of claim 1, The spherical cold mirror is an iris recognition system using a spherical cold mirror, characterized in that having a predetermined horizontal magnification.