KR20200074644A - Image acquisition system and method for acquiring a uniform interval image using an swipe line imaging sensor, and fingerprint authentication system and controller system including the same - Google Patents

Abstract

The present invention relates to a system capable of obtaining images at uniform intervals by using an image sensor that acquires a line image. The system comprises: a reference line imaging unit which acquires a reference line image for an object to be imaged which moves in one direction when a shuttering signal is received; a contrast line imaging unit which is arranged at a distance from the reference line imaging unit and continuously acquires a contrast line image for the object to be imaged which moves from the reference line imaging unit; and a displacement measuring unit which transmits a shuttering signal to the reference line imaging unit when the reference line image and the contrast line image are acquired.

Description

Image acquisition system and method for acquiring equally spaced images using a swipe line imaging sensor, and a fingerprint authentication system and controller system including the same. AUTHENTICATION SYSTEM AND CONTROLLER SYSTEM INCLUDING THE SAME}

The present invention relates to an image acquisition system and method for acquiring an equally spaced image using a swipe line imaging sensor, and more specifically, to obtain an image at a uniform interval using an image sensor that acquires a line image. This is a description of the system and the application system using it.

As various smart IoT devices such as AR (Augmented Reality), VR (Virtual Reality), and smart watches are generalized, the need for a personal information security function using biometrics has emerged.

To this end, a fingerprint recognition sensor that can be applied in a form suitable for various types of devices is required.

In general, a fingerprint recognition sensor applied to a smartphone in general is a capacitive-array sensor and occupies an area of about 1 square centimeter on a device. However, a small wearable device such as glasses or a watch has insufficient space to insert a sensor, and thus it is difficult to include a fingerprint recognition function.

Therefore, it is not possible to implement a fingerprint recognition sensor that fits within an appropriate area only by applying a method of reading a fingerprint using a partial array or a line type sensor, not an array type. The line type sensor does not have enough recognition area for fingerprint recognition, so the finger must be operated by swiping on the sensor.

Fingerprint recognition sensors, which are implemented as partial arrays or line image sensors, have been commercialized at one time. However, they are commonly distorted due to the distortion of the fingerprint image obtained due to a problem in which the speed of finger movement is inconsistent, and due to the time consuming and security incurred in restoring and processing it.

Patent Registration No. 10-1891735

Accordingly, the present invention is proposed to solve the above-mentioned problems in general, and the object of the present invention is a system capable of acquiring a uniformly spaced image using an image sensor that acquires a line image, and an application using the same. The task is to provide technology for the system.

In order to achieve the above object, an image acquisition system and method for acquiring an equally spaced image using a swipe line imaging sensor according to the technical idea of the present invention are based on an object to be moved in one direction when a shuttering signal is received. A reference line imaging unit for acquiring a line image; A control line imager arranged at a distance from the reference line imager and continuously acquiring a control line image for the image object to be moved from the reference line imager; And a displacement measurement unit that transmits a shuttering signal to the reference line imaging unit when the reference line image corresponding to the reference line image is acquired.

Also, the reference line imaging unit and the control line imaging unit may be arranged in parallel with each other.

In addition, the displacement measuring unit may be characterized in that the distance between the reference line imaging unit and the control line imaging unit calculates the moved distance of the object to be imaged.

In addition, the displacement measurement unit calculates a moving speed of the object to be imaged by using a separation distance between the reference line imager and the reference line imager, and a difference between an acquisition time of the reference line image and an acquisition time of the reference line image. It can be characterized as.

In addition, the displacement measuring unit may be characterized in that the case where the control line image is the same as the reference line image shifted in one direction is determined to correspond to each other.

In addition, the displacement measuring unit may be characterized in that it comprises an analog XOR circuit for determining whether the reference line image and the control line image correspond.

)에서 전류를 공급하는 전류원 트랜지스터와 연결되고, 게이트(gate)가 상기 기준 라인촬상부의 출력(

)을 수신하는 NMOS형의 제1트랜지스터; 소스(source)가 상기 제1트랜지스터의 소스와 연결되고, 드레인이 전류출력단(

)과 연결되며, 게이트가 상기 대조 라인촬상부의 출력(

)을 수신하는 PMOS형의 제2트랜지스터; 드레인(drain)이 상기 제1트랜지스터와 병렬로 전압입력단(

)에서 전류를 공급하는 전류원 트랜지스터와 연결되고, 게이트(gate)가 상기 대조 라인촬상부의 출력(

)을 수신하는 NMOS형의 제3트랜지스터; 소스(source)가 상기 제3트랜지스터의 소스와 연결되고, 드레인이 상기 제2트랜지스터와 병렬로 전류출력단(

)과 연결되며, 게이트가 상기 기준 라인촬상부의 출력(

)을 수신하는 PMOS형의 제4트랜지스터를 포함하는 것을 특징으로 할 수 있다.In addition, the analog XOR circuit, the drain (drain) voltage input terminal (

) Is connected to a current source transistor that supplies current, and a gate is output from the reference line imaging unit (

), a first transistor of the NMOS type; A source is connected to the source of the first transistor, and the drain is a current output terminal (

), and the gate is the output of the contrast line imaging unit (

), a second transistor of the PMOS type; The drain (drain) is a voltage input terminal in parallel with the first transistor (

) Is connected to a current source transistor that supplies current, and a gate is output from the control line imaging unit (

), a third transistor of the NMOS type; A source is connected to the source of the third transistor, and a drain is connected to the current output terminal in parallel with the second transistor (

), and the gate is the output of the reference line imaging part (

It may be characterized in that it comprises a PMOS-type fourth transistor for receiving ).

In addition, the analog XOR circuit may further include an offset invalidating unit for invalidating an offset to prevent an error due to a threshold voltage when the reference line image is compared with the reference line image.

In addition, the displacement measurement unit may be characterized in that it is determined that the corresponding control line image acquired before the predetermined minimum time after acquiring the reference line image does not correspond.

In addition, if the corresponding control line image is not acquired for a predetermined maximum time after acquiring the reference line image, the displacement measurement unit may transmit a shuttering signal to the reference line image pickup unit.

In addition, the control line imaging unit, the reference line imaging unit is arranged at a distance, the first control line imaging unit for continuously acquiring a first control line image for the image object; And a second control line imager arranged at a distance from the first control line imager and continuously acquiring a second control line image with respect to the imaged object, wherein the displacement measurement unit includes the first control line image and the When the second reference line image corresponds to the reference line image, a shuttering signal may be transmitted to the reference line imager.

In addition, the separation distance between the reference line imaging unit and the first contrast line imaging unit and the separation interval between the first contrast line imaging unit and the second contrast line imaging unit may be different from each other.

In addition, the reference line imaging unit and the control line imaging unit may constitute a line imaging set, and a plurality of the line imaging sets may be arranged.

In addition, the plurality of line image sets may be characterized in that they are arranged in at least one of sequential arrangement, cross arrangement, orthogonal arrangement, and zigzag arrangement.

In addition, in order to direct the linear motion of the imaging object, it may be characterized in that it further comprises a guide extending from one end of the reference line imaging portion to the direction of one end of the control line imaging portion.

On the other hand, in order to achieve the above object, the image acquisition method of acquiring an equally spaced image using the swipe line imaging sensor according to the technical idea of the present invention is an imaging in which the reference line imaging unit moves in one direction when a shuttering signal is received. Obtaining a reference line image for the object; Continuously acquiring a control line image with respect to the imaging object that the control line imaging unit moves from the reference line imaging unit side; A displacement measuring unit contrasting the reference line image and the control line image; And when the displacement measurement unit finds the control line image corresponding to the reference line image, transmitting a shuttering signal to the reference line image pickup unit.

The step of comparing the reference line image and the reference line image by the displacement measurement unit may be characterized in that the reference line image is also the same as the reference line image shifted in one direction.

In addition, after the step of continuously acquiring the control line image by the control line imaging unit, the displacement measurement unit further comprising the step of determining that the corresponding control line image acquired before the predetermined minimum time after acquiring the reference line image is not compatible. It can be characterized by doing.

In addition, after the displacement measurement unit compares the reference line image and the control line image to each other, if the displacement measurement unit acquires the reference line image and a corresponding control line image is not acquired for a predetermined maximum time, the reference line image is taken. It may be characterized in that it further comprises the step of transmitting a shuttering signal to the unit.

According to an image acquisition system and method for acquiring an equally spaced image using the swipe line imaging sensor according to the present invention,

First, even if the moving speed of the object to be imaged is not uniform, the line image obtained from the line imaging unit has a uniform interval.

Second, since the next image is imaged when the reference line imager and the contrast line imager are matched and matched, a process for calculating the moving speed of the object to be imaged is unnecessary.

Third, since the line images are acquired at uniform intervals, a normal image can be obtained even by simply merging the line images. Therefore, post-processing to correct the stretched or reduced image is unnecessary.

1 is a configuration diagram of an image acquisition system for acquiring an equally spaced image according to an embodiment of the present invention.
FIG. 2 shows a process in which the image acquisition system of this embodiment acquires a reference line image against an object to be moved in a direction from a reference line imaging unit to a control line imaging unit, and then acquires a next reference line image when a corresponding matching line image is received Drawing shown.
3 is a graph showing that the intervals of accumulated line images are constant even when shuttering is performed at different timings.
4 is a perspective view showing a form in which the reference line imaging unit and the control line imaging unit of this embodiment are disposed in the housing.
5 is a view showing that the reference line imaging unit and the control line imaging unit are arranged side by side at intervals and constituted by the listed image sensors.
FIG. 6 is a diagram showing a state in which an analog XOR circuit connects a reference line imager and a control line imager.
7 is a circuit diagram of an analog XOR circuit.
8 is a diagram showing signal timing for an offset elimination operation of an offset invalid part.
9 is a view showing an embodiment consisting of a plurality of control line imaging unit.
10 is a view showing various forms in which a plurality of line imaging sets may be arranged.
11 is a perspective view showing an embodiment in which a guide is formed in a housing.
12 is a flowchart of an image acquisition method for acquiring an equally spaced image according to an embodiment of the present invention.
13 is a configuration diagram of a fingerprint authentication system according to an embodiment of the present invention.
Fig. 14 is a diagram showing that a finger swipes over the line imaging section.
Fig. 15 is a diagram showing an area of a fingerprint to be imaged when a finger is over the line imaging section.
16 is a diagram showing a process of generating a 2D image by connecting a line image by an image combination unit of a fingerprint authentication system.
FIG. 17 is another embodiment, showing that a finger swipes over a cylinder.
18 is a block diagram of a controller system according to an embodiment of the present invention.
19 is a diagram showing a module of a fingerprint authentication system actually manufactured.
FIG. 20 is a graph showing a fingerprint image and a shuttering signal obtained from a fingerprint authentication system actually manufactured.
FIG. 21 is a diagram showing that the same feature points are included as a result of photographing the same part of a finger several times in an actual fingerprint authentication system.

An image acquisition system and method for acquiring equally spaced images using the swipe line imaging sensor according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention can be variously changed and can have various forms, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosure form, it should be understood to include all modifications, equivalents, or substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals are used for similar components.

In addition, unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. Terms, such as those defined in a commonly used dictionary, should be interpreted to have meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present application. Does not.

Referring to FIG. 1, an image acquisition system 100 for acquiring an equally spaced image using a swipe line imaging sensor according to an embodiment of the present invention is a reference for an imaging object moving in one direction when a shuttering signal is received And a reference line imaging unit 112 for acquiring a line image. The reference line imaging unit 112 is spaced apart from the reference line imaging unit 112, and includes a matching line imaging unit 114 for continuously acquiring a control line image for an image object to be moved from the reference line imaging unit 112 side. And a displacement measurement unit 150 that transmits a shuttering signal to the reference line imaging unit 112 when a reference line image corresponding to the reference line image is acquired.

Since this embodiment uses an image sensor arranged in a linear fashion, the image is also acquired in a linear fashion. When the linearly acquired images are connected to each other, a two-dimensional image is formed. It is assumed that an image used for generating a 2D image uses a reference line image.

This embodiment can be applied to an environment in which an object is subjected to pattern detection on an outer circumferential surface. As an example, it is possible to be applied to a fingerprint authentication system. At this time, the object to be imaged is a human finger print.

Referring to FIG. 2, using this embodiment, continuous image acquisition at equal intervals is possible. It is assumed that the object to be imaged moves from the reference line imager 112 to the control line imager 114. The reference line imaging unit 112 performs imaging on the object to be imaged to obtain a reference line image (FIG. 2(a1)). The displacement measurement unit 150 stores the acquired reference line image. After the reference line image is acquired, the contrast line imaging unit 114 continuously captures the facing area (Fig. 2(b1)). When the object to be imaged moves and the portion included in the reference line image finally reaches the control line imaging unit 114, the control line image becomes the same as the reference line image (FIG. 2(c1)). At this time, the displacement measurement unit 150 transmits a shuttering signal to the reference line imaging unit 112. The reference line imaging unit 112 receiving the shuttering signal captures a new reference line image and repeats the process of acquiring the image (FIG. 2(a2)).

The reference line imaging unit 112 and the control line imaging unit 114 are spaced apart at regular intervals (D). When it is confirmed that the reference line image has been moved to the control line imaging unit 114, imaging is performed, and if this process is repeated, a line image obtained by photographing the object to be captured at a certain distance unit (D) is obtained. In this method, since a line image of a uniform distance unit is obtained without calculating the moving speed of the object to be imaged, it is possible to obtain an intact two-dimensional image of the object to be imaged by simply combining the images obtained without additional post-processing. In addition, since it is driven by a simple contrast between the reference line imaging unit 112 and the contrasting line imaging unit 114, it can be implemented by contrasting only the equality of values using a logic circuit on a circuit without a separate algorithm.

In addition, since the reference line image is photographed on the control line imaging unit 114 in the same way as the next reference line image is imaged, it is obtained even if the imaging timing of the reference line imaging unit 112 continues to be different as shown in FIG. 3. The intervals of the line images become uniform with each other.

Subsequently, embodiments of the present invention will be specifically described.

4, the reference line imaging unit 112 and the control line imaging unit 114 are arranged side by side on the housing 180 supporting this configuration. The housing 180 functions to support the reference line imaging unit 112 and the control line imaging unit 114 to maintain a constant distance.

The thickness of the reference line imaging unit 112 and the control line imaging unit 114, and the separation distance D thereof, can be accurately realized in a few micrometers by using a semiconductor manufacturing process. When this precisely manufactured embodiment is applied to a fingerprint authentication system, tens to thousands of line images are acquired even if a finger moves only 1 mm, thereby enabling generation of a precise two-dimensional image.

Referring to FIG. 5, the reference line imaging unit 112 and the contrasting line imaging unit 114 are configured such that an image sensor for acquiring one pixel image is arranged. In this embodiment, the image sensors are arranged in a row (1×n). The reference line image and the control line image acquired correspondingly become long formed images. The image sensor may be composed of a plurality of rows such as 2×n and 3×n.

The displacement measuring unit 150 may calculate the moved distance of the object to be imaged by using the separation distance D between the reference line imaging unit 112 and the control line imaging unit 114. The reference line image, which is confirmed to correspond to the control line image, means that the object to be imaged is moved by a spaced apart distance D between the reference line imager 112 and the control line imager 114. If the reference line image is multiplied by the number obtained and the separation distance (D), the moving distance of the object to be captured is easily calculated.

The displacement measuring unit 150 uses the separation distance D between the reference line imaging unit 112 and the control line imaging unit 114 and the difference between the acquisition time of the reference line image and the acquisition time of the control line image, and You can also calculate the movement speed. By dividing the difference between the acquisition time of the reference line image and the acquisition time of the reference line image at the separation interval D, the moving speed of the image pickup object is easily calculated. In addition, by using the speed of the reference line image in the early stage and the speed of the reference line image in the latter stage, it is also possible to calculate the acceleration of the object to be imaged.

Referring to FIG. 6, the displacement measuring unit 150 of this embodiment includes an analog XOR circuit for determining whether a reference line image and a control line image correspond. The analog XOR circuit is disposed between the image sensors included in the reference line imaging unit 112 and the control line imaging unit 114 to determine whether each line image is compatible. For example, the n-th image sensor of the reference line imaging unit 112 and the n-th image sensor of the control line imaging unit 114 may be connected by an analog XOR circuit. At this time, the displacement measurement unit 150 determines that the reference line image and the control line image correspond to each other if the total sum of values indicated by the coincidence among the comparison values of the analog XOR circuits configured corresponding to the number of image sensors is greater than a preset reference. .

The displacement measuring unit 150 may determine that the control line images correspond to each other even when the reference line images shifted in one direction are the same. That is, it is possible to compensate even if the object to be imaged moves slightly out of the intended direction. For example, in the fingerprint authentication system 200, even if a finger does not pass through the reference line imaging unit 112 and the contrast line imaging unit 114 in a straight line, it may be corrected even if it passes to the left or right.

The displacement measurement unit 150 shifts the pattern of the control line image to the left or right by a predetermined range and can compare it with the reference line image. As a result of comparison, if there is the most similar result, it is determined that the reference line image and the control line image correspond to each other.

Referring to the drawings, when the analog XOR circuit of this embodiment connects the image sensor of the reference line imaging unit 112 and the image sensor of the contrast line imaging unit 114, it connects with each nth image sensor, and also contrast line imaging It was implemented by connecting in parallel with the n-1th and n+1th image sensors from the negative 114 side. As the complexity of the circuit increases, it is possible to connect n-2th and n+2th image sensors.

In addition, a configuration for improving resolution may be further included. The vertical spatial resolution is determined by the separation distance between the reference line imaging unit 112 and the control line imaging unit 114. In this embodiment, the shuttering signal generated by the displacement measuring unit 150 is interpolated using a PLL. The reference line imaging unit 112 is photographed at a higher frequency by the shuttering signal interpolated using the PLL, so that a higher resolution image can be acquired.

)에서 전류를 공급하는 전류원 트랜지스터와 연결되고, 게이트(gate)가 기준 라인촬상부(112)의 출력(

)을 수신하는 NMOS형의 제1트랜지스터(151); 소스(source)가 제1트랜지스터(151)의 소스와 연결되고, 드레인이 전류출력단(

)과 연결되며, 게이트가 대조 라인촬상부(114)의 출력(

)을 수신하는 PMOS형의 제2트랜지스터(152); 드레인(drain)이 제1트랜지스터(151)와 병렬로 전압입력단(

)에서 전류를 공급하는 전류원 트랜지스터와 연결되고, 게이트(gate)가 대조 라인촬상부(114)의 출력(

)을 수신하는 NMOS형의 제3트랜지스터(153); 소스(source)가 제3트랜지스터(153)의 소스와 연결되고, 드레인이 제2트랜지스터(152)와 병렬로 전류출력단(

)과 연결되며, 게이트가 기준 라인촬상부(112)의 출력(

)을 수신하는 PMOS형의 제4트랜지스터(154)를 포함한다.Referring to FIG. 7, in the analog XOR circuit of this embodiment, the drain has a voltage input terminal (

) Is connected to a current source transistor that supplies current, and a gate is output from the reference line imaging unit 112 (

), the first transistor 151 of the NMOS type; The source is connected to the source of the first transistor 151, and the drain is the current output terminal (

), and the gate is the output of the contrast line imaging unit 114 (

) PMOS-type second transistor 152 for receiving; The drain (drain) is a voltage input terminal in parallel with the first transistor (151) (

) Is connected to a current source transistor that supplies current, and a gate is output from the control line imager 114 (

), a third transistor 153 of the NMOS type; The source is connected to the source of the third transistor 153, and the drain is the current output terminal in parallel with the second transistor 152 (

), and the gate is the output of the reference line imaging unit 112 (

), and a fourth transistor 154 of the PMOS type.

)은 제1트랜지스터(151) 및 제4트랜지스터(154)의 게이트에 입력되고, 대조 라인촬상부(114)의 출력(

)은 제2트랜지스터(152) 및 제3트랜지스터(153)의 게이트에 입력된다.That is, the output of the reference line imaging unit 112 (

) Is input to the gates of the first transistor 151 and the fourth transistor 154, and the output of the contrast line imaging unit 114 (

) Is input to the gates of the second transistor 152 and the third transistor 153.

)에 비례하여 전류(

)를 출력한다. 아날로그XOR 회로는 제1트랜지스터(151) 및 제2트랜지스터(152)로 구성되는 좌측 가지(branch)와, 제3트랜지스터(153) 및 제4트랜지스터(154)로 구성되는 우측 가지를 가진다. 좌측 가지는 제1트랜지스터(151) 및 제2트랜지스터(152)가 모두 ON 되고,

의 조건이 만족되는 경우 전류가 흐르게 한다. 우측 가지는 제3트랜지스터(153) 및 제4트랜지스터(154)가 모두 ON 되고,

의 조건이 만족되는 경우 전류가 흐르게 한다. 이때,

는 제2트랜지스터(152) 및 제4트랜지스터(154)의 역치전압이고,

은 제1트랜지스터(151) 및 제3트랜지스터(153)의 역치전압이다. 즉, 기준 라인촬상부(112)와 대조 라인촬상부(114)의 출력이 어떤 가지에서든

만큼 차이가 있으면 해당 가지는 ON 된다.The analog XOR circuit is the square value of the voltage difference between the reference line imaging unit 112 and the control line imaging unit 114 (

) Proportional to the current (

). The analog XOR circuit has a left branch composed of a first transistor 151 and a second transistor 152, and a right branch composed of a third transistor 153 and a fourth transistor 154. The left branch has both the first transistor 151 and the second transistor 152 turned on,

When the condition of is satisfied, current flows. On the right branch, the third transistor 153 and the fourth transistor 154 are both turned on,

When the condition of is satisfied, current flows. At this time,

Is a threshold voltage of the second transistor 152 and the fourth transistor 154,

Is a threshold voltage of the first transistor 151 and the third transistor 153. That is, the outputs of the reference line imaging unit 112 and the contrast line imaging unit 114 are from any branch.

If there is much difference, the branch is turned on.

)가 흐르게 된다.When any one branch is ON, the transistor of the branch is in the saturation region, and the current having the relationship of Equation 1 by the expression of the transistor saturation region (

) Flows.

[Equation 1]

At this time, K is an arbitrary proportional constant. That is, after any one branch is turned on, the current increases in proportion to the square of the output voltage difference between the reference line imaging unit 112 and the control line imaging unit 114.

)와, 각 게이트와 드레인을 연결하는 스위치(

,

)을 포함한다.In addition, the analog XOR circuit of this embodiment further includes an offset invalidating section that invalidates the offset to prevent an error due to a threshold voltage when the reference line image and the contrast line image are compared. The offset invalid portion is a capacitor connected to each gate of the first transistor to the fourth transistor (

) And switches connecting each gate and drain (

,

).

,

)에 의해 연결되면 피드백이 형성되고, 이때 일정한 전류(

)가 흐르게 되면 게이트 전압(

)과 소스 전압(

)의 차이가 오프셋 전압이 포함된 전류(

)를 흐르게 한다. 트랜지스터의 포화영역 동작 식

에서,

와

가 확정되면

가 결정될 수 있게 된다.

의 값은

의 오차가 고려되어 자동으로 설정된다.The gate and drain of the transistor are switched (

,

) To form a feedback, where a constant current (

) Flows, the gate voltage (

) And source voltage (

The difference between) is the current that contains the offset voltage (

). Saturation region operation formula of transistor

in,

Wow

Is confirmed

Can be determined.

The value of

The error of is taken into account and set automatically.

)와 대조 라인촬상부(114,

)의 출력이 입력될 때 개별적으로 오프셋 제거가 실시된다. 제1트랜지스터(151) 및 제4트랜지스터(154)는 동일 타이밍에 오프셋을 제거하고, 제2트랜지스터(152) 및 제3트랜지스터(153)는 동일 타이밍에 오프셋을 제거한다. 오프셋 제거 시, 전류(

)와 소스 전압(

)을 고정(

)하고, 스위치(

,

)가 게이트와 드레인을 연결하여 게이트 전압(

)이 자동으로 설정되게 한다. 게이트 전압(

)과 기준 라인촬상부(112) 또는 대조 라인촬상부(114)의 출력 전압의 차가 커패시터(

)에 저장되어,

의 부정확성에 관계없이 입력전압(

,

)의 변화는 출력 전류(

)의 일정한 변화로 나타나게 된다.8 is a view showing a timing for the offset removal operation of the offset invalid portion. Reference line imaging section (112,

) And contrast line imaging section (114,

), the offset removal is performed individually when the output is input. The first transistor 151 and the fourth transistor 154 remove the offset at the same timing, and the second transistor 152 and the third transistor 153 remove the offset at the same timing. When removing offset, current(

) And source voltage (

Fixed)

) And switch (

,

) Connects the gate and drain to the gate voltage (

) Is set automatically. Gate voltage (

) And the difference between the output voltage of the reference line imaging section 112 or the control line imaging section 114 is a capacitor (

),

Regardless of the inaccuracy of

,

) Changes the output current (

).

In the first case in which a very similar image is captured by the control line imaging unit before the reference line image passes, the displacement measurement unit 150 may not recognize that the area of the detection object included in the reference line image has passed the control line imaging unit. An error can occur in 2 cases. When the first case occurs, a problem occurs in that the interval between the acquired line images is not uniform. When the second case occurs, the displacement measurement unit 150 falls into a loop that only continues to prepare the reference line image and the contrast line image, and the acquisition of the line image is stopped.

In order to prevent the first case, the displacement measuring unit 150 determines that all of the control line images acquired before the predetermined minimum time after acquiring the reference line images are not supported. For example, when the separation distance between the reference line imaging unit 112 and the control line imaging unit 114 is 100 μm, the minimum time may be 100 μs. It is preferable that the minimum time is set to a time that is unlikely to occur in the image pickup object. In the case of recognizing a fingerprint, it will be difficult for a finger to have a movement speed of 1 m/s or more.

In addition, in order to prevent the second case, the displacement measurement unit 150 transmits a shuttering signal to the reference line imaging unit 112 if the corresponding line image is not acquired for a predetermined maximum time after acquiring the reference line image. do. For example, when the separation interval between the reference line imaging unit 112 and the control line imaging unit 114 is 100 μm, the maximum time may be 1 ms. When the shuttering signal is forcibly transmitted after the maximum time, the reference line image acquisition and contrast process is restarted, thereby preventing a situation in which image acquisition is completely stopped.

Referring to FIG. 9, the contrast line imaging unit 114 according to another embodiment is arranged at a distance D1 from the reference line imaging unit 112, and the first contrast to continuously acquire the first contrast line image with respect to the imaged object Line imaging unit 114; And a second collating line imaging unit 114 arranged at a distance D2 from the first collating line imaging unit 114 and continuously acquiring a second collating line image for the object to be imaged. At this time, the displacement measurement unit 150 is implemented by transmitting a shuttering signal to the reference line image capturing unit 112 when the first and second control line images correspond to the reference line image. When it is determined that the first control line image corresponds to the reference line image, re-confirmation may be performed with the second control line image. In addition, since the opportunity to prepare at least two reference line images is generated, it is possible to minimize the occurrence of the second case.

The separation distance D1 between the reference line imaging unit 112 and the first control line imaging unit 114 and the separation interval D2 between the first contrast line imaging unit 114 and the second contrast line imaging unit 114 Can be different from each other.

Referring to FIG. 10, as another embodiment, the reference line imaging unit 112 and the control line imaging unit 114 constitute a line imaging set 110, and the line imaging set 110 is on the housing 180. It can be implemented as being arranged in plural.

The plurality of line imaging sets 110 may be arranged in at least one of sequential arrangement, cross arrangement, orthogonal arrangement, zigzag arrangement, and circular arrangement.

Fig. 10(a) is an embodiment of sequential arrangement. The line imaging set 110 was arranged side by side at the top and bottom. When the line imaging set 110 is composed of a plurality, it is possible to solve the problem that it was not possible to acquire an image as much as the separation interval of the contrast line imaging unit 114 after the reference line imaging unit 112 is photographed.

Fig. 10(b) is an embodiment of the cross arrangement. In (b), the reference line imaging units 112a and 112b of each line imaging set 110 are disposed first, and each of the control line imaging units 114a and 114b is disposed below.

10(c) is an embodiment of an orthogonal arrangement. In (c), the two line imaging sets 110 are arranged orthogonally in the middle of each other. When such an orthogonal arrangement method is applied, there is an advantage in that an image can be acquired even if the object to be imaged moves in any direction. If the orthogonally arranged line imaging set 110 is used, it can also be used as a joystick direction control button.

10(d) is another embodiment of the orthogonal arrangement. (d) is characterized in that the other line imaging sets 110 are orthogonally arranged on both sides of the center line imaging set 110 to form an H-shape. The orthogonal arrangement may also be implemented as four line imaging sets 110 arranged orthogonally at both ends of each other to form a square.

Figure 10 (e) is an embodiment of a zigzag (zigzag) arrangement. In (e), the second line imaging set 110b is disposed at an acute angle at one end of the first line imaging set 110a, and the third line imaging set 110c also has an acute angle with the second line imaging set 110b. It is characterized by being arranged while forming.

10(f) is an embodiment of a circular arrangement. (f) is characterized in that the reference line imaging section 112 is arranged in an arc on the outer circumferential surface, and the contrast line imaging section 114 having a shape corresponding to the inner circumferential surface is arranged.

Although various arrangement examples of the line imaging set 110 have been described, it is obvious that the arrangement method may vary according to an implementation method or an application environment.

In the long run, if the pattern of the object to be imaged is orthogonal to the direction of the line image, normal driving may be difficult. For example, if there is a section formed orthogonally to the line imaging set 110 among the fingerprint patterns, the displacement measurement unit 150 may misinterpret that the control line image continues to correspond in the section. At this time, the above problems can be solved if the line imaging set 110 arranged in a method such as orthogonal arrangement, zigzag arrangement, circular arrangement, or the like is applied.

When a plurality of line imaging sets 110 are configured, the displacement measurement unit 150 may transmit a shuttering signal when a reference line image and a control line image correspond to any one of the plurality of line imaging sets 110. . In addition, the shuttering signal may be transmitted only when the reference line image and the control line image correspond in all of the plurality of line image sets 110.

Referring to FIG. 11, in order to direct the linear motion of the imaged object, a guide 182 that protrudes from one end of the reference line imaging unit 112 to the direction of one end of the control line imaging unit 114 is further included. can do. As illustrated, the guide 182 may be formed to extend in a direction orthogonal to the line imaging units on both sides of the line imaging units 112 and 114 of the housing 180. As another embodiment, it is possible to form the guide 182 even if the portion in which the line imaging units 112 and 114 of the housing 180 are disposed is recessed in a direction perpendicular to the line imaging unit.

Next, an image acquisition method for acquiring an equally spaced image according to an embodiment of the present invention will be described.

Referring to FIG. 12, this embodiment includes a step of acquiring a reference line image for an image object to be moved in one direction when the reference line imaging unit 112 receives a shuttering signal (S120); A step in which the control line imaging unit 114 continuously acquires a control line image with respect to the object to be imaged moving from the reference line imaging unit 112 (S130); The displacement measuring unit 150 contrasts the reference line image and the contrast line image (S150); And when the displacement measurement unit 150 finds a control line image corresponding to the reference line image, transmitting a shuttering signal to the reference line imaging unit 112 (S160).

In step S150, the case where the control line image is the same as the reference line image shifted in one direction is also contrasted.

After step S130, the displacement measuring unit 150 further includes a step of determining that the corresponding control line image acquired before the preset minimum time after acquiring the reference line image is not corresponding (S140).

If it is determined in step S150 that the reference line image and the control line image do not correspond to each other, the displacement measurement unit 150 acquires the reference line image, and if the corresponding control line image is not acquired for a preset maximum time, the reference line image is taken. Further comprising the step of transmitting the shuttering signal to the unit 112 (S170).

The image acquisition method for acquiring an equally spaced image of this embodiment may include detailed features of the image acquisition system 100 described above.

Next, a fingerprint authentication system 200 including an image acquisition system 100 for acquiring equally spaced images according to an embodiment of the present invention will be described.

Referring to FIG. 13, the fingerprint authentication system 200 includes an image acquisition system 100 including a reference line imaging unit 112, a control line imaging unit 114, and a displacement measurement unit 150; An image combination unit 210 for generating a two-dimensional image by combining line images obtained by shuttering of the reference line imaging unit 112; It includes a fingerprint information matching unit 220 to determine the similarity by comparing the two-dimensional image generated by the image combination unit 210 with a previously stored fingerprint image.

14 and 15, when a user swipes a finger on the line imaging units 112 and 114, the reference line imaging unit 112 acquires a fingerprint line image at regular intervals. .

Referring to FIG. 16, the image combination unit 210 connects the line images acquired by the reference line imaging unit 112 to generate one two-dimensional image. Since the line image is acquired in a certain distance unit, even if it is simply connected, an image shrinking or stretching area is not generated.

17 is another embodiment, the image acquisition system 100 uses a cylinder 117 rotated by a swipe of a finger to detect the movement speed of the finger. The image acquisition system 100 of another embodiment includes a housing 180; A transparent cylinder 117 rotatably coupled in the housing 180 and disposed on one surface of the housing 180 to be exposed; An illumination unit 111 irradiating light in a direction exposed on the surface of the housing 180 from one side of the cylinder 117, and the illumination unit 111 reflected on one side of the cylinder 117 exposed on the surface of the housing 180 It includes a continuous imaging unit 115 for receiving the light of the image acquisition.

In this embodiment, when the user raises and swipes a finger on the cylinder 117 exposed on the housing 180, the cylinder 117 rotates, and the continuous imaging unit 115 displays an image of a finger contacting the cylinder 117. Take a picture. In particular, the continuous imaging unit 115 controls the shooting speed in response to the speed at which the cylinder 117 rotates.

The image combination unit 210 may generate a two-dimensional image by arranging images captured by the continuous imaging unit 115 in response to the rotational speed of the cylinder 117.

Next, a controller system 300 including an image acquisition system 100 for acquiring equally spaced images according to an embodiment of the present invention will be described.

The image acquisition system 100 transmits a shuttering signal while the finger moves over the line imaging unit. Using this, you can make a highly sensitive scroller. If the distance between the reference line imaging unit 112 and the control line imaging unit 114 is 50 μm, a shuttering signal is generated whenever a finger moves 50 μm. This means that at least dozens of shuttering signals are generated with only a slight movement of a finger. If the interval, number of times of generated shuttering signal, and the amount of occurrence during a certain time are used as a control signal, it can be used as a high-precision controller.

Referring to FIG. 18, the controller system 300 includes an image acquisition system 100 including a reference line imaging unit 112, a control line imaging unit 114, and a displacement measurement unit 150; Using the movement distance or movement speed of the finger calculated by the displacement measurement unit 150 of the image acquisition system 100, or by using the shuttering signal pattern generated by the displacement measurement unit 150 of the image acquisition system 100 A modulation amount calculating unit 310 that calculates a moving vector and speed of a finger; It includes a control signal generator 320 for outputting a corresponding control signal using the motion vector and speed of the finger calculated by the modulation amount calculating unit 310.

The control signal output from the control signal fisher includes a scroll signal for scrolling an image searched on the display upward or downward, and a direction key signal corresponding to the up, down, left, and right direction keys.

In an image acquisition system and method for acquiring an equally spaced image according to an embodiment of the present invention, a line image with a uniform interval is obtained without calculating the moving speed of the object. Therefore, when a 2D image is generated by combining line images, there is no stretched or reduced area in the image, so post-processing for correction is not necessary. Since the computational configuration for generating a two-dimensional image of an object to be imaged is minimal, it is possible to implement it in a very small size and a very low power type. Accordingly, the fingerprint authentication system 200 can be applied to not only portable devices, but also various wearable devices, school supplies, safes, and small locks. In particular, since the line imaging unit may be formed to a thickness of nanometers to micrometers, the fingerprint authentication system 200 can be applied to an environment that has been difficult to apply in the past.

Experimental example.

Referring to FIG. 19, a chip to which an image acquisition system 100 for acquiring equally spaced images is applied and a module for acquiring images from it are manufactured.

In order to prevent a finger from directly contacting a chip to which the image acquisition system 100 is applied, and to obtain a uniform fingerprint image, (a) joins a planar glass surface on the chip, and (b) joins a hemispherical glass surface Did.

20 is a graph showing a displacement graph of a time interval of a shuttering signal generated when a finger is swiped on a chip and an obtained fingerprint image. Fig. 20(a) is obtained in Fig. 19(a), and Fig. 20(b) is obtained in Fig. 19(b).

Referring to the obtained results, it was found that the acquired image is uniform even if the swipe speed of the finger is not uniform. Referring to the graph of the shuttering signal, it can be seen that this system can be useful not only for acquiring line images, but also for the controller system 300.

21 is a view showing the results of experiments taken several times the same part of the finger. Even if the finger was photographed several times, it was confirmed that the characteristic points of the fingerprint appear uniformly in the same area of the finger fingerprint. Accordingly, it can be seen that there is no problem in acquiring a precise fingerprint image due to the slight loss of image due to the separation distance between the reference line imaging unit 112 and the line imaging unit 114.

Although the preferred embodiments of the present invention have been described above, the present invention can use various changes, modifications, and equivalents. It is clear that the present invention can be equally applied by appropriately modifying the above embodiments. Therefore, the above description is not intended to limit the scope of the present invention as defined by the following claims.

100: image acquisition system for acquiring equally spaced images
110: line imaging set 111: lighting unit
112: reference line imaging unit 114: contrast line imaging unit
115: continuous imaging unit 117: cylinder
150: displacement measuring unit 151: first transistor
152: 2nd transistor 153: 3rd transistor
154: fourth transistor 180: housing
182: Guide 200: Fingerprint authentication system
210: image combination unit 220: fingerprint information contrast unit
300: controller system 310: modulation amount calculation unit
320: control signal generation unit

Claims (21)

A reference line imaging unit for acquiring a reference line image for an object to be moved in one direction when receiving a shuttering signal;
A control line imager arranged at a distance from the reference line imager and continuously obtaining a control line image for the image object to be moved from the reference line imager; And
And a displacement measuring unit that transmits a shuttering signal to the reference line image pickup unit when the reference line image corresponding to the reference line image is acquired. According to claim 1,
The reference line imaging unit and the control line imaging unit image acquisition system for acquiring equally spaced images, characterized in that arranged in parallel with each other. According to claim 2,
The displacement measuring unit is an image acquisition system for acquiring an equally spaced image, characterized in that the distance between the reference line imaging unit and the control line imaging unit is spaced apart to calculate the moved distance. According to claim 2,
The displacement measuring unit calculates a moving speed of the object to be imaged by using a separation distance between the reference line imaging unit and the control line imaging unit and a difference between the acquisition time of the reference line image and the acquisition time of the control line image. An image acquisition system that acquires equally spaced images. According to claim 2,
The displacement measurement unit is an image acquisition system for acquiring an equally spaced image, characterized in that the control line image is identical to the reference line image shifted in one direction, and is determined to correspond to each other. The method of claim 5,
And the displacement measuring unit includes an analog XOR circuit for determining whether the reference line image corresponds to the reference line image. The method of claim 6, wherein the analog XOR circuit,
Drain is the voltage input terminal (

) Is connected to a current source transistor that supplies current, and a gate is output from the reference line imaging unit (

), a first transistor of the NMOS type;
A source is connected to the source of the first transistor, and the drain is a current output terminal (

), and the gate is the output of the contrast line imaging unit (

), a second transistor of the PMOS type;
The drain (drain) is a voltage input terminal in parallel with the first transistor (

) Is connected to a current source transistor that supplies current, and a gate is output from the control line imaging unit (

), a third transistor of the NMOS type;
A source is connected to the source of the third transistor, and a drain is connected to the current output terminal in parallel with the second transistor (

), and the gate is the output of the reference line imaging part (

And a fourth transistor of the PMOS type receiving ). The analog XOR circuit of claim 7,
The image acquisition system for acquiring an equally spaced image, further comprising an offset invalidating section for invalidating an offset in order to prevent an error due to a threshold voltage when the reference line image is compared with the reference line image. According to claim 1,
The displacement measuring unit is an image acquisition system for acquiring an equally spaced image, characterized in that it determines that the corresponding control line image acquired before a predetermined minimum time after acquiring the reference line image is not corresponding. According to claim 1,
The displacement measuring unit acquires an equally spaced image, characterized in that if the corresponding line image is not acquired for a predetermined maximum time after acquiring the reference line image, a shuttering signal is transmitted to the reference line imaging unit. . According to claim 2, The control line imaging unit,
A first collation line imaging unit arranged at a distance from the reference line imaging unit and continuously acquiring a first control line image with respect to the imaging object; And
And a second collation line imaging unit which is arranged at a distance from the first collation line imaging unit, and continuously acquires a second collation line image with respect to the imaging object,
The displacement measurement unit is an image acquisition system for acquiring an equally spaced image, characterized in that the shuttering signal is transmitted to the reference line image pickup unit when the first and second control line images correspond to the reference line image. . The method of claim 11,
An image acquisition system for acquiring an equally spaced image, characterized in that the separation interval between the reference line imaging unit and the first contrasting line imaging unit is different from that between the first contrasting line imaging unit and the second contrasting line imaging unit. . According to claim 1,
The reference line imaging unit and the control line imaging unit constitute a line imaging set,
An image acquisition system for acquiring equally spaced images, wherein a plurality of the line image sets are arranged. The method of claim 13,
An image acquisition system for acquiring equally spaced images, wherein the plurality of line image sets are arranged in at least one of sequential arrangement, cross arrangement, orthogonal arrangement, and zigzag arrangement. According to claim 2,
An image acquisition system for acquiring an equally spaced image, further comprising a guide extending from one end of the reference line imaging unit to a direction of one end of the control line imaging unit to direct the linear motion of the imaging object. . Acquiring a reference line image for an object to be imaged moving in one direction when the reference line imaging unit receives the shuttering signal;
Continuously acquiring a control line image with respect to the imaging object that the control line imaging unit moves from the reference line imaging unit side;
A displacement measuring unit contrasting the reference line image and the control line image; And
And when the displacement measurement unit finds the control line image corresponding to the reference line image, transmitting a shuttering signal to the reference line image pickup unit. The method of claim 16, wherein the displacement measuring unit contrasts the reference line image and the control line image to each other,
An image acquisition method for acquiring an evenly spaced image, wherein the reference line image shifted in one direction is also prepared. 17. The method of claim 16, After the step of continuously obtaining the control line image by the control line imaging unit,
And the displacement measurement unit determining that the corresponding control line image acquired before the preset minimum time after acquiring the reference line image is non-corresponding. The method of claim 16, After the displacement measuring unit contrasts the reference line image and the control line image to each other,
Acquiring an equally spaced image further comprising the step of transmitting a shuttering signal to the reference line imaging unit if the corresponding measurement line image is not acquired for a predetermined maximum time after the displacement measurement unit acquires the reference line image. Image acquisition method to do. When a shuttering signal is received, a reference line image pickup unit for acquiring a reference line image for a finger moving in one direction, arranged at a distance from the reference line image pickup unit, and contrasts with the finger moving from the reference line image pickup unit side An image acquisition system including a control line imager continuously acquiring a line image and a displacement measuring unit that transmits a shuttering signal to the reference line imager when the control line image corresponding to the reference line image is acquired;
An image combining unit that generates a two-dimensional image by combining the reference line images obtained from the reference line imaging unit;
A fingerprint authentication system comprising a fingerprint information matching unit to determine the similarity by comparing the two-dimensional image generated by the image combining unit with a previously stored fingerprint image. When a shuttering signal is received, a reference line image pickup unit for acquiring a reference line image for a finger moving in one direction, arranged at a distance from the reference line image pickup unit, and contrasts with the finger moving from the reference line image pickup unit side An image acquisition system including a control line imager continuously acquiring a line image and a displacement measuring unit that transmits a shuttering signal to the reference line imager when the control line image corresponding to the reference line image is acquired;
A modulation amount calculating unit for calculating the movement vector and speed of the finger using the shuttering signal pattern generated by the displacement measuring unit of the image acquisition system;
And a control signal generation unit for outputting a corresponding control signal using the motion vector and speed of the finger calculated by the modulation amount calculation unit.

Images