JP2004259173A - Pointing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the size of a contact part in a pointing device including a contact part for placing a finger thereon. <P>SOLUTION: With the finger pressed to a sensor surface 12 of a fingerprint sensor 11, the finger is shifted a little from the sensor surface, and a mouse pointer is moved in the shifting direction. WIth the finger strongly pressed to the sensor surface 12 for designated time, and then the pressure of the finger is returned to perform a click command. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pointing device that receives an operation command from an operator and causes a computer to perform a process corresponding to the operation command.
[0002]
[Prior art]
Conventionally, trackballs, trackpads, and the like have been known as pointing devices that can save installation space as compared to a mouse.
[0003]
The trackball has a sphere that is rotatably arranged, and moves a mouse pointer, a cursor, and the like displayed on a display unit of a computer according to the angle amount and the rotation direction of the sphere. However, if the sphere is downsized to reduce the size of the trackball, it will be difficult to control the rotation of the sphere with a finger accurately. Therefore, there is a certain limit to miniaturization of the sphere in consideration of operability.
[0004]
The track pad has a planar sensor surface, and moves a mouse pointer according to a moving distance of a finger slid on the sensor surface. Therefore, when the sensor surface is reduced, the distance over which the finger can slide is limited. Therefore, there is a certain limit in reducing the sensor surface.
[0005]
Therefore, a transparent plate with which an object (operator's finger) contacts is provided, and detection means for detecting the movement (change) of the image of the surface of the contacted finger is provided. A pointing device that detects a movement of an upper finger and moves a mouse pointer (cursor) based on the movement is disclosed (Patent Document 1).
[0006]
[Patent Document 1]
JP-A-2002-062983
[0007]
[Problems to be solved by the invention]
However, in the pointing device according to Patent Literature 1, in order to detect a change in an image, a finger in contact with the plate must be completely slid, and the area of the plate surface is determined in consideration of the finger sliding distance. It is necessary to set the size, and there is a certain limit to miniaturization.
[0008]
The present invention has been made to solve the above-described problems, and in a pointing device including a contact portion on which an operator's finger is placed, the size of the contact portion can be reduced while maintaining operability. The aim is to obtain a pointing device.
[0009]
[Means for Solving the Problems]
A pointing device according to the present invention is a pointing device provided with a contact portion on which an operator's finger is placed. The storage device stores a fingerprint image of the operator as a registered image in advance, and the pointing device is placed on the contact portion. Acquiring means for acquiring a fingerprint image of the finger, detecting means for detecting the movement of the finger on the contact portion by comparing the registered image with the fingerprint image acquired by the acquiring means, and the detecting means And receiving means for receiving an operation command corresponding to the detected finger movement.
[0010]
According to this configuration, the fingerprint image of the user using the computer is stored in the storage unit in advance as a registered image, and the registered image is compared with the fingerprint image acquired by the acquiring unit. It is possible to detect a slight movement of the finger, and it is possible to reduce the area of the contact portion while maintaining operability.
[0011]
Further, it is preferable that the detection means detects a finger movement based on a change in a fingerprint pattern in a fingerprint image generated when a finger placed on the contact portion is shifted with respect to the contact portion.
[0012]
According to this configuration, since the movement of the finger is detected based on the change in the fingerprint pattern, it is possible to detect the operation of slightly moving the finger along the contact portion while pressing the finger against the contact portion. From the mouse pointer can be received.
[0013]
Further, in the fingerprint image obtained by the obtaining unit, the detecting unit specifies a region of the fingerprint image in which the change in the fingerprint pattern is substantially constant as compared with the registered image as a fixed region, and determines the region of the fixed region in the fingerprint image. Preferably, the movement of the finger is detected based on the position.
[0014]
According to this configuration, when the finger is slightly moved along the sensor surface in a state where the finger is pressed against the sensor surface, focusing on the position in the fingerprint image of the fixed region, which is a region where the fingerprint pattern changes little, Since the movement is detected, the movement of the finger can be detected more accurately.
[0015]
Further, it is preferable that the detection unit detects the fixed region by extracting a reference image from the registered image and performing template matching on the fingerprint image acquired by the acquisition unit using the extracted reference image.
[0016]
According to this configuration, since the fixed region is detected by the template matching, the detection accuracy of the fixed region is improved, and the movement of the finger when the finger is slightly moved along the contact portion can be more accurately detected. it can.
[0017]
Further, it is preferable that the detection unit uses, as a template, straight lines that pass through a predetermined point in the fixed region with respect to the registered image and are orthogonal to each other.
[0018]
According to this configuration, a horizontal straight line is scanned in the vertical direction with respect to the acquired image, and a vertical straight line is scanned in the horizontal direction. That is, the vertical and horizontal straight lines are each scanned in the one-dimensional direction. Thus, the detection speed of the fixed region can be increased.
[0019]
Further, the detection means may detect the movement of the finger based on a change in the area of the fingerprint area of the fingerprint image acquired by the acquisition means with respect to the fingerprint area of the registered image.
[0020]
According to this configuration, it is possible to detect a change in finger pressure applied in a direction perpendicular to the sensor surface, and to accept a click command from the user.
[0021]
Further, the detection means may detect a finger movement based on a change in the shape of the fingerprint image of the fingerprint image acquired by the acquisition means with respect to the fingerprint area of the registered image. According to this configuration, it is possible to detect a state in which the finger in contact with the contact surface is set up and a state in which the finger in contact with the contact surface is lying down.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a diagram showing an external configuration of a pointing device according to an embodiment of the present invention. This pointing device includes a fingerprint sensor 1 and a computer 2. The fingerprint sensor (acquisition means) 1 and the computer are electrically connected by a cable 3.
[0023]
The fingerprint sensor 1 is a fingerprint sensor of a capacitance type, an optical type, a pressure sensing type, or the like, and includes a rectangular parallelepiped housing 11 and a sensor surface 12 (contact portion) disposed above the housing 11. It has an external configuration. In FIG. 1, the area of the sensor surface 12 is shown larger than the actual size in order to make the drawing easier to see.
[0024]
FIG. 2 is a diagram showing a schematic configuration of a capacitance type fingerprint sensor. As shown in FIG. 2, the capacitance type fingerprint sensor 1 includes an electrode group 112 in which a protective film 111 and electrodes 112a are arranged in predetermined rows and columns. Each electrode 112a has a characteristic that the amount of charge varies depending on the unevenness of a finger placed on the protective film 111, that is, the distance between the protective film 111 and the surface of the finger. Therefore, the charge amount of the electrode 112a on which the (concave) portion of the fingerprint groove is placed is smaller than the charge amount of the electrode on which the (convex) portion of the fingerprint is placed. Then, the electric charge charged on each electrode 112a is converted into, for example, a voltage value corresponding to the amount of the electric charge, and the voltage value is converted into a digital value, thereby obtaining a fingerprint image.
[0025]
In the following description, a fingerprint image refers to a rectangular image including a region (fingerprint region) in which a user's fingerprint is represented. Further, the vertical direction of the fingerprint image refers to the direction of the fingerprint image corresponding to the arrow A on the sensor surface 12 shown in FIG. 1, and the horizontal direction of the fingerprint image corresponds to the arrow B of the sensor surface 12 shown in FIG. Refers to the direction of the fingerprint image. The upward direction of the fingerprint image indicates the direction indicated by arrow A, and the downward direction indicates the direction opposite to the direction indicated by arrow A. The horizontal direction of the display screen 41 is defined as an X direction, and the direction orthogonal to the X direction is defined as a Y direction. The lower left vertex P1 of the display screen 41 is set as the origin, the coordinate axis in the X direction is set as the X coordinate, and the coordinate axis in the Y direction is set as the Y coordinate.
[0026]
The computer 2 includes a CPU that executes various programs, a ROM (read only memory) that stores a basic input / output system (BIOS) that is a program for controlling peripheral devices, and a RAM (random access memory) used as a work area of the CPU. ), An operating command from a user including a hard disk for storing various data, a flexible disk, a recording medium driving device for reading data recorded on a recording medium such as a CD-ROM, a DVD, a keyboard, a mouse, etc. Is a personal computer comprising an operating device for receiving and outputting to the CPU and a CRT (cathode ray tube) or a liquid crystal panel and including a display device 4 for displaying various images under the control of the CPU.
[0027]
The pointing device according to the present invention is realized by installing a program for causing a computer to function as a processing unit of the pointing device in the computer 2. When this program is recorded on, for example, a CD-ROM or a flexible disk, the program is stored in the recording medium drive by loading and installing the CD-ROM or the flexible disk in the recording medium drive. When the program is stored in a web server on the Internet, the program may be downloaded from the web server and installed to be stored in the recording medium drive.
[0028]
FIG. 3 shows a block diagram of the pointing device. The pointing device detects a finger movement using a fingerprint image (registered image) of a user registered in advance in a registration mode.
[0029]
The acquired image storage unit 31 mainly includes a RAM, and temporarily stores a fingerprint image acquired by the fingerprint sensor 1 as an acquired image.
[0030]
The registered image storage unit 32 is mainly composed of a hard disk, and stores, as a registered image, a fingerprint image of the user's fingertip (for example, the forefinger) obtained in advance in the registration mode. The registered image storage unit 32 can store fingerprint images of a plurality of users who use the computer 2 as registered images. In this case, the registered image storage unit 32 stores the area of the fingerprint area of each registered image specified by the fingerprint area specifying unit 22 described later in association with the registered image.
[0031]
Although both the acquired image and the registered image are fingerprint images, for convenience of explanation, a previously registered fingerprint image is represented as a registered image, and an image temporarily stored in the RAM is separately represented as an acquired image.
[0032]
The program execution unit 20 is mainly composed of a CPU, and the CPU executes a program recorded on the hard disk to cause the computer to function as a processing unit of the pointing device. 22, a motion determining unit 23, a fixed area specifying unit 24, a moving amount calculating unit 25, a mouse pointer moving command receiving unit 26, a scroll command receiving unit 27, a click command receiving determining unit 28, and a click command notifying unit 29.
[0033]
In the registration mode, the registration image specifying unit 21 performs template matching on the registration images of a plurality of users stored in the registration image using the obtained image as a template, and registers the registration image whose fingerprint pattern matches the registration image. It is determined whether or not the stored image is stored in the image storage unit 32. If a registered image having a matching fingerprint pattern is stored in the registered image storage unit 32, the registered image is currently used by the computer 2. It is specified as a registered image of the user. On the other hand, if the matching registered image is not stored in the registered image storage unit 32, the acquired image is stored in the registered image storage unit 32 as a new user's registered image.
[0034]
The fingerprint area specifying unit 22 performs predetermined image processing, for example, edge detection processing on the fingerprint image or the registered image acquired by the fingerprint sensor 1 to extract the outline of the fingerprint area, and extracts the pixels existing in the extracted outline. The area of the fingerprint area is calculated from the number.
[0035]
The operation determining unit 23 determines whether or not a value (area difference) obtained by subtracting the area of the fingerprint area of the registered image from the area of the fingerprint area of the acquired image is larger than a predetermined value (threshold TH). If it is greater than TH, it is determined that the user has issued a click command. In addition, when the area difference is smaller than the threshold value TH, the operation determining unit 23 further determines whether the fingerprint region is biased toward a predetermined upper or lower region in the fingerprint image, and determines whether the fingerprint region is upward or downward. If it appears to be biased to the side, it is determined that the scroll command has been issued by the user, and if it does not appear to be biased upward or downward, it is determined that the user has issued a mouse pointer movement command.
[0036]
The fixed region specifying unit 24 performs template matching on the acquired image using a rectangular region having a predetermined size in the vertical and horizontal directions with the center of gravity of the fingerprint region of the registered image as the center of gravity, and specifies the fixed region from the obtained image. I do. For the template matching, a matching method for each pixel, a matching method using principal component analysis, and the like are used.
[0037]
The movement amount calculation unit 25 specifies the center point of the fixed region of the acquired image, divides the fingerprint region into two regions on the left and right by a vertical straight line passing through the center point, and calculates the difference between the areas of the left and right regions. The value is calculated, and the movement amount of the X coordinate of the mouse pointer is calculated from the difference value. Further, the movement amount calculation unit 25 divides the fingerprint area into two upper and lower areas by a horizontal straight line passing through the center point, calculates a difference value between the areas of the upper and lower areas, and calculates the difference value of the mouse pointer from the difference value. The movement amount of the Y coordinate is calculated.
[0038]
The mouse pointer movement command receiving unit 26 adds the current X coordinate value of the mouse pointer to the X coordinate movement amount of the mouse pointer calculated by the movement amount calculation unit 25 and calculates the X coordinate value of the mouse pointer. A new coordinate position of the mouse pointer is calculated by adding the current value of the Y coordinate of the mouse pointer to the movement amount of the Y coordinate of the mouse pointer. Then, the mouse pointer is erased from the currently displayed coordinate position, and displayed at the newly calculated coordinate position.
[0039]
When the operation determining unit 23 determines that the fingerprint area exists in the upper predetermined area in the fingerprint image, the scroll instruction receiving unit 27 receives an upward scroll instruction from the user and displays the upward scroll instruction on the display screen 41. Scroll the image in the current window upward. In addition, when the operation determining unit 23 determines that the fingerprint area exists in the predetermined lower area in the fingerprint image, the scroll instruction receiving unit 27 receives a downward scroll instruction from the user, and displays the display screen 41. Scroll the image in the displayed window downward.
[0040]
The click command acceptance determination unit 28 counts how many times the acquired image in which the area of the fingerprint area is larger than the threshold value TH is continuously acquired, and when the counted value is larger than a predetermined value, the click from the user is clicked. When a command is received and the counted value is smaller than a predetermined value, a click command from the user is not received.
[0041]
The click command notifying unit 29 is configured such that, when the click command reception determining unit 28 receives a click command from a click by a user, an object displayed on the same coordinates as the mouse pointer when the user clicks is clicked. To the various programs executed.
[0042]
Next, a registration mode executed to acquire a registration image will be described. FIG. 4 is a flowchart showing a processing procedure in the registration mode. First, in step S1, the fingerprint sensor 1 acquires a fingerprint image of a fingertip of a user placed on the sensor surface 12. The registration mode is executed, for example, when the user starts the computer.
[0043]
In step S2, the registered image specifying unit 21 searches the registered image storage unit 32 to determine whether a registered image whose fingerprint pattern matches the acquired image obtained in step S1 is stored in the registered image storage unit 32. judge.
[0044]
In step S3, when a registered image whose fingerprint pattern matches the acquired image is stored in the registered image storage unit 32 (YES in step S3), the registered image specifying unit 21 uses the computer 2 to store the registered image. It is specified as a registered image of the user who is (step S4).
[0045]
In step S3, if the registered image whose fingerprint pattern matches the acquired image is not stored in the registered image storage unit 32 (NO in step S3), the acquired image acquired in step S1 is stored as a new registered image. It is stored in the unit 32 (step S5).
[0046]
In step S6, the fingerprint area specifying unit 22 calculates the area of the fingerprint area of the new registered image obtained in step S3. In step S7, the registered image specifying unit 21 stores the area of the fingerprint area calculated in step S6 in the registered image storage unit 32 in association with the registered image (step S7).
[0047]
Next, a process for receiving an operation command from a user based on an acquired image will be described. FIG. 5 is a diagram for explaining the operation of the finger performed by the user to issue various operation commands to the computer 2 in the pointing device. Arrows Y1 to Y4 shown in the figure indicate the movement of the fingertip F when the fingertip F is slightly shifted in the directions of the arrows Y1 to Y4 in a state where the fingertip F is pressed against the sensor surface 12. The operations shown by the arrows Y1 to Y4 are performed to move the mouse pointer displayed on the display screen 41, and the pointing device receives these operations as a mouse pointer movement command from the user.
[0048]
FIGS. 6A and 6B are diagrams for explaining a change in the fingerprint image with respect to the movement of the finger. FIG. 6A illustrates a fingerprint image obtained when the user places the finger on the sensor surface 12 and does not issue an operation command. (B) shows a fingerprint image obtained when the user performs the operation shown by the arrow Y2, and (c) shows a fingerprint image obtained when the user performs the operation shown in the arrow Y1 direction. Is shown. When the user slightly shifts the finger in the direction indicated by arrow Y2, the fingerprint pattern of the fingerprint image shown in (a) changes to the fingerprint pattern of the fingerprint image shown in (b). At this time, before and after the change, there is an area where the fingerprint pattern does not change (fixed area KD) and an area where the fingerprint pattern changes (slip area GD) is compared with (a) and (b). It can be understood by: In the fingerprint image shown in (c), it can be seen that the fixed area KD and the slip area GD similarly exist. As can be seen by comparing (b) and (c), when the fingertip F is shifted in the direction indicated by the arrow Y2, the sliding area GD appears on the left side of the fixed area KD, but the fingertip F is moved to the arrow Y1. , The sliding area GD appears on the right side of the fixed area KD. As described above, it can be seen that the relative position of the sliding area GD with respect to the fixed area KD greatly differs depending on the movement of the finger. Therefore, the pointing device determines the operation of the fingertip F from the relative positional relationship of the fixed region KD in the fingerprint region SD, and accepts a user's mouse pointer movement command.
[0049]
Arrow Y5 indicates the operation of the fingertip F when the fingertip F is strongly pressed against the sensor surface 12 by increasing the pressure of the fingertip F in the direction of gravity with respect to the sensor surface 12, and arrow Y6 indicates the sensor surface. The operation of reducing the pressure of the fingertip F pressed strongly against the pressure 12 and returning the pressure to the original state is shown, and the pointing device receives these operations as a click command from the user.
[0050]
The arrow Y7 indicates an operation when the finger FB is raised against the sensor surface 12 while the fingertip F is pressed against the sensor surface 12 (by increasing the inclination angle θ between the sensor surface 12 and the finger FB). The pointing device accepts this operation as an upward scroll command from the user. In addition, the arrow Y8 indicates an operation of resting the entire finger on the sensor surface 12 (an operation of decreasing the inclination angle θ between the sensor surface 12 and the finger), contrary to the operation indicated by the arrow Y7. The pointing device accepts this operation as a downward scroll command from the user. Here, the upward scroll refers to scrolling the screen in the window displayed on the display screen 41 in the Y direction, and the downward scroll refers to the screen in the window displayed on the display screen 41 in the −Y direction. Means scrolling.
[0051]
FIG. 7 is a flowchart illustrating a procedure of a process for receiving an operation command from a user. First, in step S11, the fingerprint sensor 1 acquires a fingerprint image of the fingertip F placed on the sensor surface 12, and stores the fingerprint image in the acquired image storage unit 31. The fingerprint sensor 1 acquires fingerprint images at predetermined time intervals (for example, 1/10 seconds).
[0052]
In step S12, the operation determination unit 23 performs an operation determination process for determining whether the movement of the user's finger is a mouse pointer movement command, a click command, or a scroll command from the acquired image acquired in step S11. Do.
[0053]
In step S13, when the operation determining unit 23 determines that the command is a click command, the process proceeds to step S14, where a click command receiving process for determining whether to receive the click command is performed (step S14), and the movement of the mouse pointer is performed. When it is determined that the command is a command, the process proceeds to step S15, where a mouse pointer movement command receiving process, which is a detailed process for receiving a command to move the mouse pointer, is performed. A scroll command receiving process for determining whether to receive a command is performed.
[0054]
FIG. 8 is a flowchart showing a subroutine of the operation determination process in step S12. First, in step S121, the fingerprint area specifying unit 22 specifies the fingerprint area from the acquired image and obtains the area of the fingerprint area. FIG. 9 is a diagram illustrating an example of a fingerprint image acquired by the fingerprint sensor 1. As shown in FIG. 9, a fingerprint area SD is shown over the entire screen. In the fingerprint area SD, a portion corresponding to a groove (recess) of the fingerprint appears black, and a fingerprint peak (convex portion) corresponds to the fingerprint. It can be seen that the white area appears white and the fingerprint is represented by a black and white stripe pattern. The fingerprint area specifying unit 22 detects the outline of the fingerprint area SD and calculates the area of the fingerprint area SD from the number of pixels included in the outline. Note that the fingerprint area specifying unit 22 represents the fingerprint area SD with a solid black color by filling a white stripe portion of the fingerprint area SD with black, and calculates the area of the fingerprint area SD from the number of pixels represented by black. May be.
[0055]
In step S122, the motion determining unit 23 subtracts the area of the fingerprint area of the registered image specified in the registration mode from the area of the fingerprint area calculated in step S121, and calculates an area difference value.
[0056]
In step S123, the operation determination unit 23 determines whether or not the area difference value calculated in step S122 is larger than the threshold value TH (step S123). If the area difference value is larger than the threshold value TH (step S123) (YES in S123), it is determined that the user has issued a click command (step S125).
[0057]
As the pressure in the direction of gravity of the fingertip F with respect to the sensor surface 12 is increased, the area of the contact surface between the sensor surface 12 and the fingertip F increases, and the area of the fingerprint region in the fingerprint image increases. Go. Therefore, the operation determining unit 23 determines a click command from the user based on whether or not the area of the fingerprint area is larger than the threshold value TH.
[0058]
On the other hand, when the area difference value calculated in step S122 is smaller than the threshold value TH (NO in step S123), the operation determination unit 23 determines whether the fingerprint area is biased toward the upper or lower area. It is determined (step S124), and if the area is biased toward the upper or lower area (YES in step S124), it is determined that the scroll command has been issued (step S126). On the other hand, in step S124, when the fingerprint area is not biased toward the upper or lower area (NO in step S124), the operation determining unit 23 determines that the user has issued a mouse pointer movement instruction (step S124). Step S127).
[0059]
FIG. 10 is a flowchart showing the mouse pointer movement command accepting process shown in step S15. First, in step S21, the fixed region specifying unit 24 specifies a fixed region from the fingerprint image acquired in step S11. FIGS. 11A and 11B are diagrams schematically illustrating a fingerprint image for explaining template matching performed by the fixed region specifying unit 24. FIG. 11A illustrates a registered image, and FIG. 11B illustrates an acquired image. The fixed region specifying unit 24 specifies the center point from the fingerprint region of the registered image specified by the fingerprint region specifying unit 22. The center point is specified, for example, by fitting a rectangle circumscribing the fingerprint area, dividing one side of the fitted rectangle in the vertical direction at a predetermined ratio, and drawing a straight line drawn in the horizontal direction from the divided position, and a horizontal line of the fitted rectangle. One side in the direction is divided at a predetermined ratio, and an intersection with a straight line drawn in the vertical direction from the divided position is specified as a center point. The predetermined ratio when dividing one side in the vertical and horizontal directions is obtained, for example, by obtaining fingerprint images of a plurality of users as samples and using an average value of the ratio of these samples. Thereby, as shown in FIG. 11A, the fixed area KD is specified for the registered image, and the center point CP of the specified fixed area KD is specified.
[0060]
Next, the fixed area specifying unit 24 specifies the center point CP of the fingerprint area SD from the registered image specified in the registration mode, and defines a predetermined vertical and horizontal rectangular area having the center point CP as the center of gravity. Extract as template T. Here, it is assumed that the size of the extracted rectangular template T is smaller than the size of the fixed region KD.
[0061]
Next, the fixed region specifying unit 24 scans the template T extracted from the registered image in the X direction from, for example, the upper left vertex of the acquired image, and specifies the most matching region. Then, the center of gravity of the specified area T ′ is set as the center point CP ′ of the fixed area KD ′ (FIG. 11B).
In step S22, the fixed area specifying unit 24 sets a counter value K for counting how many acquired images have been obtained since the last time the fixed area was specified.
[0062]
In step S23, the fixed area specifying unit 24 determines whether or not the counter value K is larger than the predetermined value N. If K> = N, that is, if the fixed area KD 'is specified last time, If the number of acquired images has been acquired (NO in step S23), template matching is performed on the acquired image acquired this time to specify the center point CP 'of the fixed region KD' (step S24). ). On the other hand, if K <N in step S23, that is, if a predetermined number of acquired images have not been acquired since the last time the fixed area KD 'was specified (YES in step S23), the process proceeds to step S25. As described above, the fixed region specifying unit 24 does not perform template matching on all acquired images, but performs template matching on a predetermined number of sheets, thereby speeding up processing.
[0063]
In step S25, the fixed area specifying unit 24 specifies the center point CP 'of the fixed area KD' of the acquired image. In this case, the coordinates of the center point of the fixed area specified by the previous template matching are used as the center point CP 'of the fixed area KD'.
[0064]
In step S26, the movement amount calculation unit 25 divides the fingerprint area of the acquired image into two areas by a vertical straight line passing through the center point CP 'of the fixed area KD'. In this case, as shown in FIG. 11B, the fingerprint area SD 'is divided into two areas D1 and D2 by a vertical straight line L1 passing through the center point CP' of the specified fixed area KD '.
[0065]
In step S27, the movement amount calculation unit 25 calculates the respective areas S1 and S2 of the regions D1 and D2, and calculates a difference value ΔS1 (= S2−S1) between the areas of the regions D1 and D2.
[0066]
In step S28, the movement amount calculation unit 25 calculates the movement amount ΔX of the mouse pointer with respect to the X coordinate of the display screen 41 from the difference value ΔS1. The movement amount ΔX may be calculated, for example, by obtaining a conversion coefficient from the relationship between the horizontal size of the display screen 41 and the horizontal size of the fingerprint image, and multiplying the conversion coefficient by the difference value ΔS1. Alternatively, the conversion function may be calculated by obtaining a conversion function from the relationship between the horizontal size of the display screen 41 and the horizontal size of the fingerprint image, and substituting the difference value ΔS1 into the conversion function.
[0067]
In step S29, the movement amount calculator 25 draws a horizontal straight line L2 passing through the center point CP 'of the fixed region KD', and divides the fingerprint region SD 'into two regions D3 and D4.
[0068]
In step S30, the movement amount calculation unit 25 calculates the areas S3 and S4 of the regions D3 and D4, and calculates a difference value ΔS2 (= S4−S3) between the areas of the regions D3 and D4.
[0069]
In step S31, the movement amount calculation unit 25 calculates the movement amount ΔY of the mouse pointer with respect to the Y coordinate of the display screen 41 from the difference value ΔS2. The movement amount ΔY is calculated by a conversion coefficient or a conversion function, similarly to the movement amount ΔX.
[0070]
In step S32, the mouse pointer movement command receiving unit 26 calculates X ′ = X + ΔX for the coordinates (X, Y) of the mouse pointer currently displayed on the display screen 41, and sets Y ′ = By calculating Y + ΔY, new coordinates (X ′, Y ′) of the mouse pointer are calculated. Then, the mouse pointer displayed at the coordinates (X, Y) is deleted, and the mouse pointer is displayed at the new coordinates (X1, Y1).
[0071]
In step S33, the fingerprint sensor 1 acquires a fingerprint image. Next, in step S34, the sticking area specifying unit 24 updates the counter value K by adding 1 to the counter value K.
[0072]
In step S35, the operation determination unit 23 performs the operation determination process shown in step S12, and when the operation determination unit 23 determines that the instruction is a mouse pointer movement instruction (YES in step S36), the process returns to step S23. On the other hand, in step S36, when the operation determination unit 23 determines that the instruction is not a mouse pointer movement instruction (NO in step S36), the process returns to step S13 illustrated in FIG.
[0073]
In this manner, when the processing of the flowchart of FIG. 10 is repeatedly executed, the mouse pointer moves at a higher speed as the distance of the finger shifted with respect to the sensor surface 12 increases. If the calculated new coordinates (X1, Y1) exceed the displayable range of the display screen 41, the mouse pointer stops at the edge of the displayable range.
[0074]
Next, the click command acceptance determination process shown in step S14 will be described. FIG. 12 is a flowchart showing the subroutine of step S14. First, in step S40, the click command reception determination unit 28 sets a counter value K for counting how many consecutively acquired images having a larger fingerprint area than the threshold value TH to 1, and sets the counter value K to 1. Initialize the value K.
[0075]
In step S41, the fingerprint sensor 1 acquires a fingerprint image. In step S42, the click command reception determining unit 28 updates the counter value K by adding 1 to the counter value K. In step S43, the operation determining unit 23 determines whether the area of the fingerprint area is smaller than the threshold value TH (step S43). If the area of the fingerprint area is larger than the threshold value TH (NO in step S43), Returning to step S41, a new fingerprint image is obtained. On the other hand, if the area of the fingerprint area is smaller than the threshold value TH (YES in step S43), the process proceeds to step S44.
[0076]
In step S44, the click command acceptance determination unit 28 determines whether the value of the counter value K is greater than a predetermined value N (step S44). If N> K (YES in step S44), Click command from is accepted. When a click command is received from the user, the click command notification unit 29 notifies various programs that the click command has been performed. For example, when an icon is clicked by the user, the color of the icon is highlighted. When the button for maximizing the display of the window displayed on the display screen 41 is clicked, the window is maximized on the display screen 41.
[0077]
Further, when the click command is received twice within a predetermined time, a double-click command may be issued. When the user double-clicks an icon, the application software associated with the icon is activated.
[0078]
Next, a scroll command acceptance determination process will be described. FIG. 13 is a flowchart showing a subroutine of step S16. First, in step S51, the operation determining unit 23 determines whether the fingerprint area exists in a predetermined area above the fingerprint image (step S51), and determines that the fingerprint area exists in the upper predetermined area (step S51). (YES in S51), scroll instruction receiving unit 27 receives an upward scroll instruction from the user (step S52).
[0079]
FIG. 14 is a diagram showing a state where the fingerprint area is displayed in a predetermined area above the fingerprint image. In the present embodiment, as shown in FIG. 14, for example, the scroll instruction receiving unit 27 draws a straight line L3 in the horizontal direction from the midpoint MP of the vertical side H1 of the acquired image, and If the fingerprint area SD ′ exists in the upper area UD, it is determined that the scroll command has been issued. In addition, the point on the side H1 where the straight line L3 is drawn is not limited to the midpoint MP, and may be appropriately changed according to the size of the fingerprint image.
[0080]
In step S52, the scroll command receiving unit 27 performs a display process of scrolling the screen in the window, for which the upward scroll command has been issued, upward.
[0081]
In step S51, when the scroll command receiving unit 27 determines that the fingerprint area is not biased toward the predetermined area above the fingerprint image (NO in step S51), that is, the fingerprint area is located below the fingerprint image. When the display is biased to the predetermined area, the scroll command receiving unit 27 receives a downward scroll command.
[0082]
In step S55, the scroll command receiving unit 27 performs a display process of scrolling the screen in the window, for which the downward scroll command has been issued, upward.
[0083]
In the above embodiment, the program execution unit 20 and the storage unit 40 use the CPU, the RAM, and the hard disk of the computer 2. You may. In this case, the size of the pointing device itself can be reduced by reducing the size of the sensor surface 12.
[0084]
In the above-described embodiment, the fixed region specifying unit 24 uses a rectangular template as a template for specifying a fixed region from an acquired image. However, the present invention is not limited to this. As shown in FIG. A vertical straight line L4 passing through the center point CP of the fixed area and a horizontal straight line L5 passing through the center point CP are used as templates, and the obtained image is scanned with the straight line L4 in the horizontal direction to find the best match. The vertical line to be extracted is extracted, and a straight line L5 is scanned in the vertical direction with respect to the acquired image to extract the best matching horizontal line, and the intersection of the extracted vertical and horizontal lines is determined. The center point CP ′ of the fixing region may be used. In this case, by scanning the straight lines L4 and L5 in one of the vertical and horizontal directions, the center point CP 'of the fixed region KD' can be calculated, so that the processing can be speeded up.
[0085]
In the above embodiment, the fingerprint sensor 1 is connected to the outside of the computer 2. However, the present invention is not limited to this. When the pointing device is applied to a notebook computer, the fingerprint device is integrated with the notebook computer. May be connected. In this case, since the area of the sensor surface 12 can be reduced, the notebook personal computer itself can be reduced in size.
[0086]
【The invention's effect】
According to the present invention, the user can issue various operation commands to the computer by slightly moving the finger placed on the contact portion, and thus the contact portion can be downsized.
[Brief description of the drawings]
FIG. 1 is a diagram showing an external configuration of a pointing device according to an embodiment of the present invention.
FIG. 2 is a diagram showing a schematic configuration of a capacitance type fingerprint sensor.
FIG. 3 shows a block diagram of the pointing device.
FIG. 4 is a flowchart showing a processing procedure in a registration mode.
FIG. 5 is a diagram for explaining a finger operation performed by a user in order to issue various operation commands to a computer in the pointing device.
6A and 6B are diagrams for explaining a change in a fingerprint image with respect to a movement of a finger. FIG. 6A illustrates a fingerprint image obtained when the user places a finger on a sensor surface and does not issue an operation command. (B) shows a fingerprint image obtained when the user performs the operation shown by the arrow Y2, and (c) shows a fingerprint image obtained when the user performs the operation shown by the arrow Y1 direction ing.
FIG. 7 is a flowchart illustrating a procedure of a process for receiving an operation command from a user.
FIG. 8 is a flowchart of an operation determination process.
FIG. 9 is a diagram illustrating an example of a fingerprint image acquired by a fingerprint sensor.
FIG. 10 is a flowchart showing a mouse pointer movement command accepting process.
FIGS. 11A and 11B are diagrams schematically illustrating a fingerprint image for explaining template matching performed by a fixed region specifying unit, wherein FIG. 11A illustrates a registered image and FIG. 11B illustrates an acquired image.
FIG. 12 is a flowchart of a click instruction receiving process.
FIG. 13 is a flowchart of a scroll command receiving process.
FIG. 14 is a diagram showing a state where a fingerprint area is displayed in a predetermined area above a fingerprint image.
[Explanation of symbols]
1 Fingerprint sensor (acquisition means)
2 Computer
3 cable
4 Display device
11 Case
12 Sensor surface (contact part)
20 Program execution unit
21 Registered image specifying unit
22 Fingerprint area specifying unit (detection means)
23 operation determination unit (detection means)
24 Fixed area specifying part (detection means)
25 Movement amount calculation unit (detection means)
26 Mouse pointer movement command receiving unit (receiving means)
27 Scroll command receiving unit (receiving means)
28 Click command reception judgment unit (reception means)
29 Click command notification section
31 Acquired image storage unit
32 Registered image storage
40 storage unit
41 Display screen
111 protective film
112a electrode
112 electrode group

Claims (7)

A pointing device having a contact portion on which an operator's finger is placed,
Storage means for storing a fingerprint image of the operator as a registered image in advance;
Acquisition means for acquiring a fingerprint image of a finger placed on the contact portion,
Detecting means for detecting the movement of the finger on the contact portion by comparing the registered image and the fingerprint image obtained by the obtaining means,
A pointing device for receiving an operation command corresponding to the movement of the finger detected by the detection unit. 2. The apparatus according to claim 1, wherein the detecting unit detects a finger movement based on a change in a fingerprint pattern in a fingerprint image generated when a finger placed on the contact unit is displaced with respect to the contact unit. A pointing device as described. In the fingerprint image obtained by the obtaining unit, the detecting unit specifies a region of the fingerprint image in which a change in the fingerprint pattern is substantially constant as compared with the registered image as a fixed region, and determines a position of the fixed region in the fingerprint image. The pointing device according to claim 2, wherein a movement of a finger is detected based on the detection. The detection unit detects a fixed image by extracting a reference image from the registered image and performing template matching on the fingerprint image acquired by the acquisition unit using the extracted reference image. Item 4. The pointing device according to item 3. 5. The pointing device according to claim 4, wherein the detection unit sets straight lines passing through a predetermined point in the fixed region and orthogonal to each other as the reference image. 6. The method according to claim 1, wherein the detecting unit detects a finger movement based on a change in an area of a fingerprint area of the fingerprint image acquired by the acquiring unit with respect to a fingerprint area of the registered image. A pointing device according to claim 1. The method according to claim 1, wherein the detection unit detects a finger movement based on a change in a shape of the fingerprint image acquired by the acquisition unit with respect to a fingerprint area of the registered image. pointing device.

Images