JPH0239822B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a personal authentication device installed at an automatic transaction device or an entrance to a room where outsiders are prohibited.

[Background of the invention]

Conventional cash dispensing devices perform a cash disbursement operation if the personal identification number information recorded on the card matches the information keyed in by the individual. However, with this method, there is a concern that a third party could easily withdraw cash if, for example, the card and the memo with the PIN number are lost at the same time. As a countermeasure to this problem, a method has been proposed in which each person's voiceprint is compared, as in Utility Model No. 52-1217539, but this method requires a frequency analyzer and requires a large amount of information to be registered, so the memory is large. There is the problem of getting used to it, and since it requires a human being to actually produce the voice, it is a method that is difficult to accept for people who dislike voicing their own voice in front of the public, and it is also susceptible to the influence of external voice noise. There were problems such as the need for soundproofing equipment because it was easy to use.

Furthermore, it is possible to use an individual's fingerprints as personal authentication, but there is generally resistance to having fingerprints taken, and when fingerprints are turned into information, the amount of information becomes large, which has the same drawbacks as the former.

[Purpose of the invention]

In view of the above points, the present invention uses finger information to
To provide a personal authentication device which has high identification reliability and security, and which can authenticate an individual regardless of the way the hand is placed when recognizing hand and finger information.

[Summary of the invention]

The present invention focuses on the fact that the size and area of each individual's fingers is unique, and registers information about each individual's fingers in advance, and compares this registered information with the hand and finger information of the person to be authenticated collected at the time of authentication. This is a device that performs personal authentication by performing personal authentication, and in particular, when collecting hand and finger information, it is possible to determine whether the information matches the registered information through predetermined calculations without having to fix the position of the hand. .

[Embodiments of the invention]

The first embodiment will be described below with reference to FIGS. 1 to 3.

In FIGS. 1 and 2, 1A to 1C are guide grooves provided in the flat sensor portion 14, and are used to determine the positions of the index finger, middle finger, ring finger, etc., respectively. In the deep central part of each guide groove, optical sensors 5A to 5C are lined up and embedded near where the tip 6a of the finger is located when the hand is placed on the sensor part, and the arrangement pitch of the optical sensors is set to 1 mm. Numeral 7 is a plurality of light emitting elements placed approximately 50 mm above the hand, arranged to correspond to each sensor, and emitting parallel light toward the corresponding sensor. Reference numeral 8 denotes a push button for turning on the power of the light emitting element 7 and the authentication device, which is pressed by the person to be authenticated. In this example, data is collected from the left hand, so press with the right hand.

To prevent the user's hands from sweating during use,
A plurality of air blowing holes 9 are provided on both sides of the grooves 1A to 1C. In addition, in order to alleviate the discomfort during use, the temperature sensor 12 detects the surface temperature of the detection part, and if it is cold, the buried heater 11 increases the surface temperature. The cleaning pad 10 is made of a replaceable cloth and is used by the user to remove moisture and dirt.

Since the surface of each sensor 5A to 5C gets dirty when used by the person to be authenticated, the output level is checked without fingers after each use, and if the level is low, the circuit is designed to issue an error message. configured.

In FIG. 3, reference numeral 13 indicates a sensor section, and 14 indicates a memory 1 for storing information regarding the hand and fingers from the sensor section 13.
7, and if the discrimination section 15 makes a negative discrimination, the information regarding the hand and fingers from the sensor section 13 is transferred to the registration section 16 or the memory 1.
7, an arithmetic unit that performs correction using the registered hand information of the individual; 16, a registration unit that holds the hand information of each individual in advance for authentication; This is a discrimination unit that compares hand and finger information to determine whether they are the same or not, and generates a discrimination signal _S13 .

In the above configuration, an actual authentication operation will be explained. First, the person to be authenticated places his left hand on the surface of the sensor section 14 with his left hand open. At this time, place the index finger, middle finger, and ring finger in contact with the grooves 1A to 1C, respectively, and press the button 8 with your right hand. All operations are started by pressing the button 8, and each sensor 5A~
5C measures the length of each finger. The sensor generates a light-shielding signal as the length of the finger increases by 1 mm, so the length of the finger is determined based on the signal value.

The information read by the sensor is converted by the calculation unit 14, and specifically, the conversion is performed according to a program in the memory 17. In this embodiment, as shown in FIG. 4, with the tip of the middle finger as the center of coordinates, a virtual straight line L is provided horizontally from this center, and the distances from this straight line to the tips of fingers other than the middle finger are determined. In this example, the measured value is zero from the straight line L to the middle finger, and the measured value is from the straight line L to the middle finger.
Let l ₁ be the length of the index finger, l ₂ be the length of the index finger, and l ₃ be the length of the little finger (in this example, the length of the little finger is also measured).

Here, each sensor element making up the sensor is 5
They are arranged horizontally in a straight line from A to 5C, and are programmed to count the number of unblocked sensor elements from this position to the tip of each finger, with the tip of the middle finger as zero. .
In addition, in the case of a person whose ring finger is longer than the middle finger, the tip of the ring finger is set as the center of coordinates, and the length from this center to the tips of the other fingers is measured.

In the example of FIG. 4, the arithmetic unit 14a in the arithmetic unit 14
The information collected from the sensor is converted as described above, and the information is collected from the index finger as hand finger information S ₁₁ .
Output l ₂ , 0, l ₁ , l ₃ in this order.

On the other hand, the registration unit 16 stores l ₂ , 0, l ₁ , and l ₃ as finger information of each person in the same format as above, and outputs them in the above order as the output signal S ₁₂ . In addition,
The hand and finger information may be stored in the registration unit 16 in a format different from that of S ₁₁ , so that when it is output as S ₁₂ , it has the same format as S ₁₁ .

The determining unit 15 sequentially compares the finger information S ₁₁ with the finger information S ₁₂ of each person generated one after another from the registration unit, and outputs a matching signal if they match within a certain range. In this case, if a password contained in a magnetic card or the like is used, only one set of finger information specified by the password will be output from the registration unit 16, and the determination can be made in a short time.

The arithmetic unit 14 can also correct the information when the hand is tilted by the corrector 14b. The correction will be described below. Note that the hand inclination is suspected when the determination unit does not output a determination signal indicating that the tilt is constant.

Next, regarding the calculations of l ₁ , l ₂ , and l ₃ mentioned above, in order to correct errors due to the inclination when setting the hand, corrections are made using coordinates with the tip of the middle finger as the origin. For example, if the same hand as in Figure 4 is set as in Figure 5, l ₁ = 6.5 → l ₁ '= 8, l ₂ = 15 → l ₂ ' = 13 l ₃ = 36 →
If this changes to ₃ ' = 39, then in order to authenticate this as the same person, data on the width of the finger tip of the person measured separately at the time of registration (recorded on the PIN card or central CPU memory) is used. ) is used. In this case, assuming the width = 16 mm, if the hand is tilted by θ from the basic state as shown in Figure 5, first calculate the virtual line S ₁ from Figure 4, then S ₁ = √ ₁ ² + 16 ² = √6.5 ² +16 ² = 17.26 Next, calculate the slope α ₁ of the virtual line S ₁ , α ₁ = Sin ^-1 (l ₁ /S ₁ ) = Sin ^-1 (6.5 / 17.26) = 22.1 degrees Figure 5 _{To find β 1} ^{from _} _{_} −α ₁ )=(27.6°−22.1°)=5.5° Below, when calculating l ₂ ′ using this θ, l ₂ ′=S ₂ ×Sinβ ₂ =S ₂ ×Sin(α ₂ −θ) Here So, S ₂ and α ₂ are calculated from Figure 1. S ₂ = √ ₂ ² + 16 ² = √ 15 ² + 16 ² = 21.93 α ₂ = Sin ^-1 (l ₂ /S ₂ ) = Sin ^-1 (15/ 21.93) = 43.15 degrees Therefore, by substituting this S ₂ and α ₂ , the calculated value of l ₂ ′ is l ₂ ′ = 21.93 × Sin (43.15 − 5.5) = 13.4 Similarly, when calculating l ₃ ′ using θ, we get l ₃ ′=S ₃ ×Sinβ ₃ =S ₃ ×Sin (α ₃ +θ) Here, S ₃ and α ₃ are calculated from Figure 4, and S ₃ =√ ₃ ² +32 ² =√36 ² +32 ² =48.16 α ₂ = Sin ^-1 (l ₃ / S ₃ ) = Sin ^-1 (36 / 48.16) = 48.37 degrees Therefore, by substituting this S ₃ and α ₃ , the calculated value of l ₃ ′ is l ₃ ′ = 48.16 × Sin ( 48.37 + 5.5) = 38.85 Reliability can be further improved by correcting the tilt of the hand using the calculations described above.

In addition, in the case of a person whose ring finger is longer than the middle finger, the above correction method will not work, so the calculation formula should be set at the tip of the ring finger as the coordinate center. In this case, l ₁ is the difference between the ring finger and the middle finger, and l ₂ is It is the difference between the ring finger and the index finger, and l ₃ is the difference between the ring finger and the little finger, and the correction calculation only needs to be changed by the amount by which the coordinate center shifts to the left by the width of the finger. These judgments can be made by simultaneously recording information as to which finger is longer, the middle finger or the ring finger, when the length of the finger is detected by the detection means. In addition, if both fingers are approximately equal, either one may be used, so in this example, the former is used for calculation.

FIG. 6 shows a modification of the sensor section. 3 is a spacer arranged on the surface of the set part so as to be located between the fingers. In this example, since the setting of the fingers can be defined, the inclination of the fingers can be further reduced. 2 is a circular guide groove provided to guide only the tip of the middle finger so that the set position of the middle finger is always at the same position.

FIG. 7 shows another modification of the sensor section. This example prevents the surface of the sensor section from becoming dirty with dust or the like, or from erroneously detecting finger lengths due to differences in nail length. Spacer 3 and projecting wall 3'
The light emitting element 7 and the sensor 5 are embedded in opposite sides of the spacer and the projecting wall. In this structure, the length of the finger is measured when viewed from the side of the finger, and the optical axis of the light emitting element is actually placed at a height of about 4 mm from the contact surface of the finger, so the nail is irrelevant. To place the finger, first set it in the circular guide groove 4 with a diameter of 10 mm and depth of 1 mm to guide the tip of the middle finger.
Next, the ring finger and index finger are placed in close contact with the spacer 3, respectively.

The example shown in FIG. 7 is also effective in reducing the tilt of the placed hand. Further, in FIG. 7, if the spacer 3 is constructed so as to be movable in the direction of the width of the finger, and the spacer is brought into close contact with the finger after the finger is set, data can be collected more accurately.

In each of the above embodiments, the difference in finger length is used as hand information, so only l ₁ , l ₂ , l ₃ and finger width dimensions are required as information held in the registration unit 16, and the amount of information is small. The storage capacity can be reduced.

In addition, in the case of the above embodiment, measurement errors are also taken into consideration, and it is determined that authentication is OK when the difference between the calculated value and the measured value is within 1.5 mm. In other cases, a message indicating the difference in finger position review is generated only once. In this example, the number of times is stored each time, and authentication is canceled at the third time.

In this example, only an example using an optical light receiving/emitting element was discussed, but in addition to this, it is also possible to use a TV camera, an infrared camera, an ultrasonic detection element, and an image sensor that is currently widely used in facsimile machines. It is also possible to use a method using these detection means, and if these detection means are used, by integrating the output signal of the finger area, the signal included in the area from the tip of the middle finger to l ₄ can be determined as shown in Figure 4. The area of the finger is calculated, and if necessary, this area value can also be registered as data.

Next, a second embodiment in which an image sensor is used as the sensor will be described using FIG. 8.
Light from a light source 21 passes through a glass plate 22 and is irradiated onto an image sensor 24 by a convex lens 23. The object 25 on the glass plate 22 is the lens 23
is projected onto the image sensor 24 by. In this case, the object 25 corresponds to the finger to be authenticated. In the above case, the n ₁ to _{n 2} bits of the image sensor 24 are shielded from light, so the binary signal obtained by slicing the video signal V at the slice level E has a polarity different from that of the other light-incident parts. It will be the opposite. Therefore, by counting the number of bits from the first bit SB to that signal using a reference clock, the position of the object can be determined.

9 and 10 show a third embodiment of the sensor section using a lever type micro switch. An operating lever 26 extends from each micro switch 25,
The tips of the operating levers are arranged near the tips of the fingers 6 at the same height. As shown in FIG. 10, when the finger 6 is placed on the sensor section, the lever 26 touched by the finger 6 rotates in the ON direction, the corresponding micro switch is turned ON, and the position of the tip of the finger is detected. In this example, we use a commercially available micro switch (width 6.4
mm) divided into top, bottom, left and right.
1.6mm detection is possible. In addition, in this example, the guide groove 27 provided on the base plate (finger contact surface)
Since the hand is placed with the fingers along the surface, the number of diagonal sets of the fingers is reduced and the detection accuracy is improved. When no finger is placed on the lever, it protrudes 2mm from the base surface. At this position, almost the tip of the flesh of the finger can be detected without falsely detecting the nail.

Next, a fourth embodiment of the sensor section using a movable image sensor will be described with reference to FIGS. 11 and 12. This sensor unit consists of a stand 31 (transparent glass is also acceptable) having a notch for transmitting light, an image sensor 33 mounted so as to slide parallelly (in the direction of the arrow) on a linear guide 32, and an image sensor 33 mounted on the top surface of these. and a light source 34. In this configuration, by pressing down a start button (not shown) after placing a hand on the stand 31, light is irradiated, and the image sensor 33 slides in the direction of the arrow to detect the length of the finger and the like.

In this example, the stand 31 is provided with a notch 36 for guiding fingers, but there is a risk that dust may fall from this notch 36 onto the image sensor. For this reason, the cleaning brush 35 for removing dust is attached to the stand 3.
1 is installed downward. Although not shown, a barcode plate is provided to indicate the distance traveled by the image sensor. A barcode is used when the image sensor moves in parallel, and a rotary encoder is used when it rotates.

Figures 13 and 14 detect when the fingers are too wide.
This method determines that the setting is OK and collects data when an alarm is issued and the maximum clearance becomes 2 mm or less. E in Figure 14 (gap 2mm or less)
F (no gap) is OK, G (gap 2mm or more)
becomes NG (no good). In this case, the table 37 on which the fingers are placed to detect the gap between the fingers is made of transparent glass or the like. Therefore, a wiper 38 is provided for cleaning fat and dirt attached to the fingers.
is attached to the top surface of the glass stand 37. However, in order to set the middle finger in a fixed direction, there is a notch 39 in the center with a width of 12 mm and a depth of 3 mm.

When collecting data, use a method that ignores the data in this area.

Next, a fifth embodiment of the sensor section will be described using FIGS. 15 to 17. This is a sensor unit that uses a movable ultrasonic sensor. Three ultrasonic sensors 42 are disposed along with a mounting base 43 at the bottom of a base 41 having a notch for placing a finger so as to be slidable in the arrow (←→) direction by a linear guide mechanism. Ultrasonic waves are emitted from the sensor 42 in the direction shown by the solid upward arrow, and when they hit an obstacle such as a finger, they are reflected as shown by the broken arrow and detected by the sensor 42 . Therefore, the finger part can be detected using this reflected wave, and the length of the finger can be detected.

Specifically, three notches 43 with a width of 10 mm are provided in the table 41, and since ultrasonic waves normally pass through these and are dispersed upward, it takes a long time for them to be reflected.
If a finger is present, a portion of the reflection occurs from the finger surface and the reflection time becomes short, so the presence or absence of the finger is determined based on this difference.

Next, sixth and seventh embodiments of the sensor section will be described with reference to FIGS. 18 to 21. In FIG. 18, a lever 53 is provided which is slidably supported on a support base 52 fixed above a base 51 having a notch for placing a finger and is biased (approximately 10 g force) in the direction of the arrow. There is. A piece 54 is provided at the tip of the lever 53 and comes into contact with the tip of a finger. During authentication, the lever advances toward the tip of the finger. The lever 53 stops when it hits the tip of the finger, and the length of the finger is detected by a linear scale 55 provided at its rear end. The scale has a striped pattern as shown in FIG. The light from the light source 57 is focused by the lens 58 and transmitted through the scale to form the index grating 62.
The stripes on the scale are applied to the light receiving sensor 60 through the lens 59. The output of the sensor 60 is applied to a counter 61, which counts the number of stripes corresponding to the amount of movement of the scale.

In FIG. 20, a rotary type detection lever is used as the detection lever, and this lever 71 rotates around 72 and is biased counterclockwise. Reference numeral 73 denotes a middle finger tip positioning guide with which the tip of the middle finger is brought into contact, and the detection lever 74 (always biased toward the left) detects the contact. During authentication, when the hand 6 is placed so that the middle finger 6' touches the guide 73, the lever 71 is rotated clockwise by fingers other than the middle finger. Due to this rotation, the encoder connected to the lever 71 also rotates, and the striped pattern 79 formed on the encoder surface is read. Specifically, as shown in FIG.
The light from 6 passes through the encoder and passes through the slit plate 7.
7 to an optical sensor 78. At this time, the optical sensor can read the striped code formed on the encoder and detect the length of the finger. In FIG. 20, the difference S between the lengths of the middle finger 6' and the other fingers 6 can be expressed as l×Sinθ°. If the other fingers are longer than the middle finger, θ will be negative, so the calculated value will also be negative.

Next, an eighth embodiment of the sensor section will be described using FIGS. 22 and 23. This method focuses on the fact that in addition to the difference in the length of the finger tips, the difference in length between the pressed parts of the fingers can be used as hand information. In FIG. 22, a solid line 81 indicates the outer shape of the finger, and a broken line 82 indicates the shape of the pressure contact portion during pressing. In Figure 23, 83 is a flexible insulating sheet that you can place your hand on and press against it, 8
4 is a row conductor fixed to the lower surface of the sheet 83, 85
is a conductive rubber placed under the row conductor 84;
is a row conductor placed under the conductive rubber and placed on the insulating sheet 87. 88 is a spacer arranged between the column conductors 86.

When you place your hand on the sheet 83 and press it, the 22nd
The conductors in the rows and columns corresponding to the shape shown by the broken line 82 in the figure are in contact with each other, and the length of the finger can be detected from the output signal thereof. In this example, even if dirt, dust, etc. adhere to the sheet, accurate detection can be performed as long as the flexibility of the sheet is ensured.

Next, a ninth embodiment of the sensor unit will be described using FIGS. 24 and 25. In this example, a solid-state image pickup tube is used to detect the area, partial thickness, and partial length of a finger. In FIG. 25, 81 is a lens, 82 is an image sensor that receives light passing through the lens,
83 is an image sensor driving circuit and video signal processing circuit. 84 is a rotary disc shutter, 85 is a position detection slit provided in the shutter, 86 is an exposure slit, 88 is a position sensor, 89 is a motor that rotates the disc, 90 is a motor drive circuit, and 91 is a shutter DDC circuit with one chip. It is a microcomputer.

When authenticating, place your hand on the white table and hold it approximately 300mm.
The hand is photographed from above with a TV camera. The cloth on the surface of the table is rolled up at regular intervals (duskin towel). This is a TV camera that uses a MOS or CCD image sensor, but it can also be configured with an image pickup tube type TV camera (the base has a groove for the middle finger guide).

In Figure 24, the area of the hand is from the tip of the middle finger to
It can be found by summing the black areas up to L ₁ . It is also possible to register area values from l ₄ to _{l 6} as personal finger information. Partial thicknesses W ₁ to _{W 3} are values for other finger tip positions l ₄ to _{l 6} .

In this example (finding the area), even if you spread your fingers,
In addition, correct information can be collected even if the entire hand is rotated.

Information is registered with the finger in a closed state as shown by the solid line in FIG. 26 and in an open state as shown in the broken line, and the finger is photographed in the above two ways at the time of authentication. In this case, it is preferable to move the middle finger. If authentication is performed using two methods as described above, the identification accuracy during authentication will be significantly improved.

Furthermore, a value that does not change when you open or close your fingers,
For example, if the virtual center of rotation is determined and the future length of the finger is used as information, accurate authentication can be performed regardless of whether the finger is opened or closed. How to find the virtual center is 27th
As shown in the figure, first, images are taken with the fingers slightly spread apart. Based on this image, center lines P, Q, and R of each finger are determined with the tip of the middle finger as the origin. Next, images are taken with the fingers a little more apart, and the center line P′ of each finger is again measured.
Determine Q′ and R′. Thereafter, the intersection of the two types of center lines for each finger is found and this is set as the virtual center of rotation. The lengths l ₁₂ and l ₁₃ (FIG. 26) of the fingers are the distances from these virtual centers of rotation to the tips of each finger. or
Once the virtual center is determined, l ₁₂ and l ₁₃ can also be calculated using β, the slope with respect to the center line (middle finger).

In this example, the finger will be imaged twice,
Accurate information can be collected regardless of how the fingers are spread.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, information about hands and fingers unique to an individual is used, and correction calculations are performed so as not to be influenced by the way the hand is placed during authentication. It is possible to accurately identify the person without being influenced by the person's identity, and it is extremely difficult for others to imitate the person, so crime prevention is improved.

[Brief explanation of drawings]

FIG. 1 is a front view of the sensor section of the embodiment of the present invention, FIG. 2 is a side view of the sensor in use, FIG. 3 is a block diagram, and FIGS. 4 and 5 are for collecting information on hands and fingers. Figure 6 is a front view of a partially deformed sensor unit, Figure 7 is a partial sectional view of the sensor unit with the sensor arrangement changed, and Figure 8 is an explanatory diagram for
The figure is an explanatory diagram of the second embodiment of the sensor section, FIG. 9 is a perspective view of the third embodiment, FIG. 10 is a sectional view thereof, and FIG. 11 is a side view of the fourth embodiment of the sensor section. FIG. 12 is a perspective view of the same, FIG. 13 is a perspective view of a modified example thereof, FIG. 14 is an explanatory diagram for detecting whether the fingers are too open, and FIGS. 15 and 16 are a fifth embodiment of the sensor section. FIG. 17 is a perspective view thereof, FIG. 18 is a perspective view of the sixth embodiment of the sensor section, FIG. 19 is a partial operation explanatory diagram, and FIG.
The figure is an explanatory diagram of the operation of the seventh embodiment of the sensor section.
Figure 1 is an explanatory diagram of a part of the operation, Figures 22 and 23.
The figures show an eighth embodiment of the sensor section, FIG. 22 is a diagram explaining the principle, FIG. 23 is a perspective view, and FIGS.
7 shows a ninth embodiment of the sensor section, FIG. 24 is a diagram explaining the principle, FIG. 25 is a configuration diagram of the camera, and FIG.
6 and 27 are explanatory diagrams for finding the virtual center. 13: sensor unit, 14: calculation unit, 15: discrimination unit, 16: registration unit, 17: memory, 14a: calculation unit, 14b: corrector.

Claims (1)

[Scope of Claims] 1. A registration unit that holds information on an individual's hand registered in advance for authentication; a sensor unit that reads information about the hand and fingers of the person to be authenticated during authentication; and a sensor unit that reads information about the hand and fingers from the sensor unit. a calculation unit that converts the hand and finger information output from the registration unit into a format; and a determination unit that compares the hand and finger information output from the calculation unit and the registration unit to determine whether they are the same and output a determination signal. and the arithmetic unit, when the determination unit makes a negative determination,
a correction calculation unit that performs a predetermined correction calculation based on the personal hand information from the registration unit and information regarding the finger from the sensor unit, and the determination unit: A personal authentication device characterized in that the personal authentication device is configured to determine whether or not the information regarding the personal information is the same as the personal finger information stored in the registration section. 2. When the determination by the determination unit is negative, the correction calculation unit determines the inclination from the reference finger tip position based on the finger tip position information from the sensor unit and the information from the registration unit. , and performs a predetermined calculation based on the inclination to correct the finger tip position information from the sensor unit with respect to the reference finger tip position. recognition device. 3. The personal authentication device according to claim 1, wherein the sensor section is configured to detect the position of the tip of a finger excluding a fingernail.