JP2006318018A - Fingerprint reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire an accurate fingerprint image through a simple structure in moving a finger for reading a fingerprint by a sweep sensor. <P>SOLUTION: This reader comprises guide members 14 which are elastic bodies fixed to opposed wall surfaces 11 opposed with a space larger than the finger width along the moving direction of finger at both side positions of the sweep sensor 12, the members being capable of ensuring a central part space between the opposed wall surfaces 11 which is narrower than the finger width but can ensure a size sufficient for the finger to move through the center part. The "transverse blurring" of the finger is suppressed by the guide members 14 while the finger is longitudinally inserted and drawn in contact with the sweep sensor 12 between the guide members 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fingerprint reader that easily and accurately acquires a fingerprint image by moving a finger along a guide member in order to read a fingerprint with a sweep sensor.

  In a fingerprint reading apparatus using a sweep sensor for reading a fingerprint, a finger is slid on the upper surface of the sweep sensor in a direction perpendicular to the length direction of the sweep sensor. The strip image obtained from the sweep sensor by this sliding is reconstructed into the original fingerprint image. If the finger is moved obliquely with respect to a predetermined direction during the sliding, the reconstruction needs to consider not only the vertical direction but also the horizontal direction in order to process the read image. In order to avoid such a situation, a guide member for moving the finger relative to the sweep sensor is provided so as to move the finger linearly.

  As a conventional fingerprint reader, for example, there is a fingerprint reader disclosed in Japanese Patent Application Laid-Open No. 2004-206417 (Patent Document 1).

  In this apparatus, as shown in FIG. 8, the pattern of the one-dimensional image picked up by the sweep sensor 111 is fixed on the flat surface of the base for the purpose of making it a natural finger pattern. A plate-like member having a rectangular shape in plan view that is arranged between the two guide members 112A and 112B and that is guided by the guide members 112A and 112B and is slidable in the front-rear direction with respect to the flat surface of the base. 113 is provided.

  The sweep sensor 111 is fixed immediately in front of the plate-like member 113 and the tip of the finger 1 is extended forward from the plate-like member 113 in a state where the fingertip is directed forward. In this state, the plate member 113 is moved together with the finger 1 until it abuts against the stopper member 114.

  According to this configuration, since the plate-like member 113 is moved substantially linearly by the guide members 112A and 112B, a stable fingerprint image can be acquired by fixing the finger 1 to the plate-like member 113. However, even in such a configuration, the plate-like member 113 that is slidable in the front-rear direction with respect to the flat surface of the base, the elastic spring for movement thereof, and the attached member thereof are required. Complexity cannot be avoided.

  On the other hand, a fingerprint reader with a simple structure is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-240924 (Patent Document 2).

  That is, for example, as shown in FIG. 9, the fingerprint reading apparatus has a sensor 121 with which the finger 1 comes into contact, and when the finger 1 moves on the sensor 121 in the front-rear direction while in contact with the sensor 121, The fingerprint is read. For the purpose of obtaining an accurate fingerprint image by guiding the finger 1 in a predetermined direction with respect to the sensor 121 with which the finger 1 contacts, the front side and the rear side of the sensor 121 in the moving direction (front-rear direction) of the finger 1 Are provided with ridge-shaped guide portions 122 </ b> A to 122 </ b> D for guiding the movement of the finger 1. The guide portion 122 for guiding the finger 1 may be a row of ridges, grooves, or a plurality of dot-like projections.

  In such a configuration, since the structure is simplified, it is impossible to prevent the finger from moving obliquely with respect to the direction of the guide portion, including the case of carelessness.

JP 2004-206417 A JP 2004-240924 A

  The problem to be solved is that if the finger is sufficiently guided in the predetermined direction, the complexity of the structure cannot be avoided, and if the structure is simplified, it is not possible to avoid moving the finger diagonally. is there. In particular, when attempting to obtain user authentication with a fingerprint on a small and thin portable terminal, it is desirable to use a sweep sensor in a narrow range for reading a fingerprint, and the above-described structure is inappropriate.

  The present invention moves a finger along a guide member in order to read a fingerprint with a sweep sensor and easily and accurately acquires a fingerprint image with a simple structure. An opposing wall surface that is wider than the finger width, and an elastic body that is fixed to the opposing wall surface. The space between the opposing wall surfaces is narrower than the finger width and is large enough for the finger to move in the central part. The main feature is to provide a guide member that can be used.

  And the space where a finger moves in the center part formed by the opposite wall surface may have a groove structure. Moreover, the through-hole-like structure which arrange | positions a sweep sensor in a bottom face and has a ceiling surface may be sufficient. Furthermore, a structure in which the guide member is also provided on the ceiling may be used. As a result, the finger movement space can be formed into a cylindrical shape such as a square cylindrical shape or a semi-cylindrical shape in which the elastic body surrounds the entire surface of the three sides except the sweep sensor surface.

  Furthermore, in order to correspond to the thickness of a finger for each user, the opposing wall surface is a flat opposing wall having a thickness, and the guide member is formed of an elastic body and an opposing wall, and the opposing wall A set of at least one of the walls that can be selected from a plurality of pairs having different thicknesses can be used as the guide member.

  In addition, it is equipped with an adjustment screw that adjusts and fixes the distance between the opposing wall surfaces by screwing into the opposing wall by screwing and abutting the tip against the wall surface of the device housing, and adapts to the width of the finger by screwing the adjustment screw It can also be made.

  The fingerprint reading device of the present invention has an elastic body that forms a space that is smaller than the thickness of the finger and smooth on the opposing wall surface other than the sweep sensor surface at both sides of the sweep sensor that limits the finger movement space. It is provided as a guide member. For this reason, the elastic member can hold the finger in the lateral direction with respect to the length direction of the sweep sensor, that is, the direction in which the finger moves back and forth, so that it has a simple structure and a stable finger on the sweep sensor. It is possible to move in a straight line, and it is possible to easily obtain an accurate fingerprint.

  In particular, the structure is such that the finger is held at both sides of the sweep sensor, so that even if the finger is tilted, the “displacement” detected by the sweep sensor is small, and the length of the guide member in the finger movement direction can be shortened. Also occurs. Further, since the structure described above can be provided with a sweep sensor in the thickness portion of the apparatus housing, a thin and small type such as a portable PC (personal computer), PDA (personal digital assistant), as shown in FIG. It is suitable for use in the fingerprint reader 100 attached to the mobile terminal 10 typified by a mobile phone.

  The objective of enabling a simple linear movement of the finger by holding the finger against the length of the sweep sensor with a simple structure is to confront each other at a position wider than the finger width along the finger movement direction at both sides of the sweep sensor. By providing an elastic body as a guide member that is fixed to the opposite wall surface and that is secured to the opposite wall surface so that the distance between the center portions is narrower than the finger width and that the finger can move through the center portion. ,It was realized.

  Embodiments according to the present invention will be described below with reference to the drawings. The drawings are schematic views, and their relative dimensions are different from those actually required. Moreover, the part which concerns on this invention is shown and there is a part abbreviate | omitted even if it is a structure essential for a function.

  A first embodiment of the present invention will be described with reference to FIGS. 2A and 2B.

  FIG. 2A is an explanatory diagram showing a perspective view of an embodiment of a related portion of the fingerprint reader according to the present invention. FIG. 2B is an explanatory diagram showing in cross section a structure portion that reads a fingerprint by moving the finger 1.

  In FIG. 2A, a sweep sensor 12, a control unit 13, and a pair of guide members 14 are shown in an apparatus housing 10 having a pair of opposing wall surfaces 11.

On one side of the apparatus housing 10, there is provided a groove formed with the opposite wall surface 11 as a side surface and the sweep sensor 12 as a bottom surface. The opposing wall surface 11 is provided along the moving direction of the finger 1 and has a wider interval than the finger width. The sweep sensor 12 is a sensor for reading a fingerprint, and the fingerprint contacting the surface is displayed for a predetermined time by a strip image. Each is detected and output to the control unit 13. The finger 1 shown in FIG. 2B moves back and forth between the guide members 14 with the fingerprint portion in contact with the sweep sensor 12. The strip shape of the image data described above is the shape of the sweep sensor 12, and the finger 1 moves vertically in the length direction of the strip shape.

  For example, as shown in FIG. 2B, the finger 1 is inserted in the direction of the arrow Pi on the sweep sensor 12, touched on the surface of the sweep sensor 12 in the direction of the arrow Pd, and pulled out in the direction of the arrow Po.

  The control unit 13 performs control to receive the output of the sweep sensor 12 and generate a fingerprint image. Details will be described later.

  The guide member 14 is an elastic body that is fixed to each of the opposing wall surfaces 11 having a space wider than the finger width along the finger movement direction at both side positions of the sweep sensor 12. The interval between the formed spaces is narrower than the finger width, and is large enough to move the finger 1 through the center. Therefore, the guide member 14 has a material such as silicone resin, polyurethane, and styrene-based thermoreversible elastomer having appropriate elasticity with respect to the finger 1.

  Here, the operation of the control unit 13 when executing fingerprint collection will be described.

  The control unit 13 commands the sweep sensor 12 to start fingerprint collection. Upon receiving the start command, the sweep sensor 12 continues to send the strip image to the control unit 13 at regular intervals. As shown in FIG. 2B, the user moves the finger 1 in the direction Pi through the groove of the apparatus housing 10, and pulls out the finger 1 in the direction Po while pressing the fingerprint portion of the finger 1 against the sweep sensor 12 in the direction Pd.

  During this time, the control unit 13 determines from the received image before fingerprint collection, during fingerprint collection, and after fingerprint collection, and stores only the image during fingerprint collection. The state before fingerprint collection can be judged from the fact that there is nothing in the strip image. For example, during fingerprint collection, it can be determined that a change has occurred in the strip image from the state before fingerprint collection, which is the start of fingerprint collection. This clear strip image is collected and subjected to predetermined processing. After fingerprint collection, if a specific number of strip images with nothing is continued in the state of fingerprint collection, it can be determined that fingerprint collection has been completed.

  When it is determined that the fingerprint has been collected, the control unit 13 notifies the sweep sensor 12 of the completion of fingerprint collection. Receiving the end command, the sweep sensor 12 stops the transmission of the strip image and ends the fingerprint collection.

  Although the above-described groove portion is illustrated as being located at the center of the upper end side of the apparatus housing, it may be located near any of the upper, lower, left and right end sides. In the case of a rectangular housing, the end side may be the long side or the short side. That is, in the case of a portable terminal as shown in FIG. 1, the user can use the apparatus housing 10 by rotating it.

  Since such a configuration is adopted, the finger can be moved while being pressed by the elasticity of the guide member, so that the finger can be collected without causing the finger to sway in the moving direction on the sweep sensor. Therefore, the control unit can obtain a strip image with little horizontal movement from the sweep sensor, and can easily reconstruct the original fingerprint image.

  A second embodiment of the present invention will be described with reference to FIGS. 3A and 3B.

  The difference between the second embodiment and the first embodiment is that the groove portion of the first embodiment that moves the finger 1 has a shape that forms the through hole 23.

  That is, in FIG. 3A, the sweep sensor 21 and the guide members 22 </ b> S and 22 </ b> U are shown in the device housing 20 having the through hole 23. Since the control unit is the same as that of the first embodiment, the illustration and description thereof are omitted.

  A through hole 23 in which the moving cross section of the finger 1 forms a rectangle is provided at the center of the apparatus housing 20. The through hole 23 is provided along the moving direction of the finger 1. A sweep sensor 21 is provided on the bottom surface so that the length direction is positioned perpendicular to the moving direction of the finger 1. On the other three sides, the guide member 22S is fixed to both side surfaces and the guide member 22U is fixed to the ceiling surface by elastic bodies.

  The sweep sensor 21 is the same as the sweep sensor of the first embodiment, and a description thereof is omitted.

  However, as shown in FIG. 3B, the finger 1 is pressed onto the sweep sensor 21 in the direction Pd by the elasticity of the guide members 22S and 22U, and is inserted and pulled out in the directions of the arrows Pi and Po.

  The guide member 22S is positioned on both sides of the sweep sensor 21, and the guide member 22U is fixed to the inner wall surface of the through-hole 23 at the ceiling of the through-hole 23, and has an interval wider than the finger width along the finger movement direction. Provided by an elastic body. The space between the guide members 22S and 22U and the sweep sensor 21 is narrower than the finger width. That is, the space has a size that allows the finger 1 to move while being pressed by the guide members 22S and 22U in the center. Therefore, the guide members 22S and 22U are made of a material such as silicon resin, polyurethane, and styrene thermoreversible elastomer having appropriate elasticity with respect to the finger 1.

  Although the above-described through-hole is illustrated as being located approximately at the center of the apparatus housing, it is obvious that the through-hole may be located in the vicinity of any end around the top, bottom, left, and right.

  Since such a configuration is adopted, the finger moves while being pressed by the elasticity of the guide member, so that even if the user is not aware of the pressure on the sweep sensor, the finger is almost the same on the sweep sensor. In addition to being touched by pressure, fingerprints can be collected without swaying in the direction of movement. That is, since the control unit can obtain a clear strip image that does not move in the vertical and horizontal directions from the sweep sensor, it can be easily reconstructed into the original fingerprint image.

  Accordingly, the sliding of only the fingertip is not performed, and the sliding is performed with the belly of the finger. As a result of sliding on the belly of the finger, a larger area of the fingerprint image is obtained compared to sliding with only the fingertip, and more data can be collected, making it easier to perform collation with reconstruction.

  It is possible to increase the distance between the sweep sensor of the through hole and its ceiling. The function in this state is exactly the same as in the first embodiment. Therefore, in this case, the guide member 22U in FIG. 3A can be deleted.

  A third embodiment of the present invention will be described with reference to FIG.

  In Example 3, although the through-hole cross section was shown by the rectangular cylinder shape in the said Example 2, this is deform | transformed into the semi-cylindrical cylinder shape.

  That is, in FIG. 4, the sweep sensor 31 and the guide member 32 are shown in the apparatus housing 30 having the through hole 33. Here, the finger is pressed against the sweep sensor 31 from the periphery by the guide member 32 with substantially the same pressure, and is inserted and pulled out, so that a more stable fingerprint image is obtained as compared with the first and second embodiments. be able to.

  A fourth embodiment of the present invention will be described with reference to FIG.

  FIG. 5 shows an apparatus housing 40, a sweep sensor 41, and guide members 42 and 42A. The guide member 42 has an elastic body 42E fixed to the facing wall 42F, and the guide member 42A has an elastic body 42E fixed to the facing wall 42AF. The elastic body 42E has the same shape, but the opposing wall 42F and the opposing wall 42AF have different thicknesses, and the opposing wall 42F has a thickness smaller than that of the opposing wall 42AF.

  In the illustrated apparatus housing 40, a groove for a fingerprint reader is formed in the same manner as in the first embodiment, and a sweep sensor 41 is provided at the bottom.

  In the fourth embodiment, the opposing wall surface fixed to the apparatus housing in the first embodiment is a pair of flat opposing walls 42F or 42AF each having a thickness, and the elastic body 42E is bonded and fixed to each of the opposing surfaces. is doing. Although not shown, the facing wall 42F or 42AF is provided with a groove that fits together with the apparatus housing 40 in the vertical direction on the drawing, that is, in the direction perpendicular to the length direction of the sweep sensor 41. The guide member 42 is fitted into the apparatus housing 40 and a groove (not shown) with the two opposing walls 42F as a pair, and is fixed by a fastener (not shown).

  As a result, the elastic bodies 42E fixed to the two opposing walls 42F face each other to form a space. This space is smaller than the thickness of the finger to be inserted.

  For a user whose inserted finger is thin and does not reach the elastic bodies 42E on both sides, the guide member 42A is used. That is, instead of the two facing walls 42F, the facing walls 42FA are paired with the apparatus housing 40 and fixed. The opposing wall 42F and the opposing wall 42FA have different thicknesses, and the space width is reduced by using the guide member 42A.

  In the above example, the opposing walls having the same thickness are paired. However, if one is the opposing wall 42F and the other is the opposing wall 42FA, the space width of the intermediate dimension of the above example can be formed.

  In this way, a plurality of guide members with different thicknesses are prepared, and a configuration that allows appropriate selection from among them is adopted, so it is possible to cope with finger thickness that cannot be dealt with by the elasticity of the set guide members become. In other words, the present invention can be applied to both a thin and small finger like a child and a thick and big finger like a wrestler.

  A fifth embodiment of the present invention will be described with reference to FIG.

  In FIG. 6, an apparatus housing 50, a sweep sensor 51, an elastic body 52 </ b> E and an inner wall 52 </ b> F that constitute a guide member, and a through hole 53 are shown.

  In the guide member of the fifth embodiment, in the second embodiment, the inner wall surfaces forming the three sides of the guide members 22S and 22U of the apparatus housing 20 in FIG. The elastic body 52E is bonded and fixed to the inner surface thereof. Further, the guide member of the fifth embodiment is prepared by selecting a plurality of types of inner walls 52F to which the elastic body 52E is fixed as in the fourth embodiment, in accordance with the size of the user's finger. The housing 50 and the inner wall 52F are fixed with a fastener (not shown) after forming a groove (not shown) or the like in a direction perpendicular to the paper surface, for example.

  Since such a configuration is adopted, it is possible to cope with a finger thickness that cannot be dealt with by the elasticity of the guide member due to the inner wall, as in the fourth embodiment. In other words, the present invention can be applied to both a thin and small finger like a child and a thick and big finger like a wrestler.

  A sixth embodiment of the present invention will be described with reference to FIG.

  In FIG. 7, the device housing 60, the sweep sensor 61, and the facing wall 62 </ b> F, the elastic body 62 </ b> E, and the adjustment screw 63 are shown as guide members. An elastic body 62E is fixed to the opposing wall 62F of the guide member.

  In the sixth embodiment, the thickness of the facing wall is changed in the fourth embodiment, but the relative position of the facing wall 62F is adjusted and fixed with the adjusting screw 63.

  That is, a fitting groove 64 for the facing wall 62F is provided on the bottom surface of the groove portion of the apparatus housing 60 in the length direction of the sweep sensor 61 that is the width direction. For example, the fitting groove 64 has a protruding portion in the upper opening portion as shown in the drawing except for a central portion where the facing wall 62F is inserted, and fits with the protruding portion of the facing wall 62F. Therefore, the opposing wall 62 </ b> F can move in the width direction of the finger along the fitting groove 64 when fitted in the fitting groove 64. For this reason, the position of the facing wall 62F can be appropriately adjusted to the width of the user's finger. The sweep sensor 61 is attached after the facing wall 62F is fitted in the fitting groove 64, for example.

  Further, the adjusting screw 63 is screwed with the facing wall 62F. For this reason, the protruding portion of the fitting groove 64 and the protruding portion of the facing wall 62F are fitted, and the adjustment screw 63 is screwed into the facing wall 62F, and the bottom surface of the fitting groove 64 is shown in the AA cross section. The position of the facing wall 62F can be fixed by pressing the tip of the adjustment screw 63 to the bottom. Therefore, the space interval on the sweep sensor formed by the elastic body 62E fixed to the facing surface of the facing wall 62F can be appropriately selected.

  Although FIG. 7 shows the shape of the fixed wall 62F, the shape of the fitting groove 65, and the fitting shape thereof, the shape is not limited to that shown in the figure. FIG. 7 shows a state in which the guide member and the mounting portion to the apparatus housing are changed in the apparatus housing edge groove portion of the fourth embodiment. For example, the end surface of the apparatus housing is shown in FIG. A guide member having a similar structure may be provided on the sweep sensor provided in the above. That is, in the sixth embodiment, since the guide member is fixed to the apparatus housing with the adjusting screw, unlike the first to fifth embodiments, the guide member can be arranged outside the apparatus housing.

  Since such a configuration is adopted, it is possible to cope with a finger thickness that cannot be dealt with by the elasticity of the guide member. In other words, the present invention can be applied to both a thin and small finger like a child and a thick and big finger like a wrestler.

  Necessary to absorb the change in the thickness of the moving body and easily suppress the lateral blur in the moving direction by providing a guide member using an elastic body or elastic member on both sides of the sensor position for detecting the moving body And it can be applied to essential uses.

It is explanatory drawing which showed one Embodiment of the apparatus housing | casing which mounts the fingerprint reader of this invention with the perspective view. It is explanatory drawing which showed one Embodiment in the fingerprint reader part by this invention with the perspective view. Example 1 It is explanatory drawing which showed the fingerprint reading part of FIG. 2A in the cross section. Example 1 It is explanatory drawing which showed one Embodiment of the fingerprint reader by this invention with the front view. (Example 2) It is explanatory drawing which showed the fingerprint reading part of FIG. 3A in the cross section. (Example 2) It is explanatory drawing which showed one Embodiment in the fingerprint reader part of this invention with the front view. Example 3 It is explanatory drawing which showed one Embodiment in the fingerprint reader part of this invention with the front view. Example 4 It is explanatory drawing which showed one Embodiment in the fingerprint reader part of this invention with the front view. (Example 5) It is explanatory drawing which showed one Embodiment in the fingerprint reader part of this invention with sectional drawing. (Example 6) It is explanatory drawing which showed in plan the example of the target part in the conventional fingerprint reader. It is explanatory drawing which showed in a plane an example different from FIG. 7 of the target part in the conventional fingerprint reader.

Explanation of symbols

1 finger 10, 20, 30, 40, 50, 60 device housing 11 opposite wall surface 12, 21, 31, 41, 51, 61 sweep sensor 13 control unit 14, 22S, 22U, 32, 42, 42A guide member 23, 33, 53 Through hole 42E, 52E, 62E Elastic member 42F, 42AF, 62F Confronting wall 52F Inner wall 63 Adjustment screw 64 Fitting groove

Claims (7)

  In a fingerprint reading apparatus that acquires a fingerprint image by moving a finger to read a fingerprint with a sweep sensor, the opposing wall surface is provided in the apparatus casing along the direction of movement of the finger at both sides of the sweep sensor and has an interval wider than the finger width. And a guide member that is secured to the opposite wall surface and that can secure a size such that the distance between the center portions between the opposite wall surfaces is narrower than the finger width and the finger moves at the center portion. A fingerprint reader characterized by the above.   2. The fingerprint reading apparatus according to claim 1, wherein a space formed by the opposing wall surface and in which a finger moves through a central part has a groove structure in which a ceiling part is opened.   2. The fingerprint reading apparatus according to claim 1, wherein a space formed by the opposing wall surface in which a finger moves in a central portion has a structure in which the sweep sensor is disposed on a bottom surface and a through hole having a ceiling surface is formed. There is a fingerprint reader.   4. The fingerprint reading apparatus according to claim 3, wherein the finger movement space has a cylindrical structure in which an elastic body as a guide member surrounds the entire surface of the three sides except the bottom surface of the sweep sensor.   5. The fingerprint reading apparatus according to claim 4, wherein the cylindrical structure is a quadrangular cylindrical shape or a semicylindrical shape.   The fingerprint reader according to claim 1, further comprising an opposing wall having a thickness on each of the opposing wall surfaces to which the elastic body is fixed, and the guide member includes the elastic body and the opposing wall. A fingerprint reading apparatus comprising a plurality of pairs of pairs in which one or both of the opposing walls have different thicknesses so that a thickness matching the thickness of the user's finger can be selected. 2. The fingerprint reading device according to claim 1, wherein the opposing wall surface to which the elastic body is fixed has a thickness and is fitted into the device housing, and is screwed into the opposing wall by screwing. And an adjustment screw that adjusts and fixes the distance between the opposing wall surfaces at a position that matches the thickness of the user's finger, and the guide member includes the elastic body, the opposing wall, and the adjustment screw. A fingerprint reader characterized by that.

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