JP2008149019A - Active sensor, personal identification device, portable terminal, and signal extraction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active sensor, a personal identification device, a portable terminal, and a signal extraction method for suppressing generation of false operation caused by incidence of outside light, and making devices compact. <P>SOLUTION: The active sensor 10 includes: a board 1 having a placement surface 1A facing a subject 200; a light emitting area 30A which is provided on the placement surface 1A and emits light towards the subject 200; a photodetector 20 which is provided on the placement surface 1A and detects light reflected by the subject 200; and a light separator 40 which is provided between the light emitting area 30A and the photodetector 20 on the placement surface 1A and is composed of a light-shielding materials. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an active sensor including a light receiving element and a light emitting region, a personal authentication device, a portable terminal, and a signal extraction method.

  Conventionally, portable terminals with excellent portability are generally widely known. Further, development of a system for performing prepaid electronic payment, postpaid electronic payment, immediate electronic payment, information distribution, information exchange, and the like using a mobile terminal is in progress. In developing such a system, it is essential to perform highly secure personal authentication.

  In recent years, for the purpose of improving the safety of personal authentication and reducing the burden on the user, a personal authentication device (for example, a vein authentication device) that performs personal authentication using the biometric information of the user has been proposed (for example, Patent Documents 1 to 5).

  Specifically, the personal authentication device described above detects an image forming element (such as an image forming lens) that forms an image of light reflected by a blood vessel or a fingerprint of the hand, and light imaged by the image forming element. It has an image receiving element (CCD; Charge Coupled Device, etc.) and a storage unit in which patterns such as blood vessels and fingerprints of hands are registered in advance.

The personal authentication device acquires an image such as a blood vessel or a fingerprint of a hand using an image receiving element, and then acquires a pattern such as a blood vessel or a fingerprint of the hand based on the acquired image. Subsequently, the personal authentication device collates the acquired pattern (acquired pattern) with the pattern (registered pattern) stored in the storage unit. The personal authentication device determines that the user is valid if the acquired pattern matches the registered pattern, and determines that the user is not valid if the acquired pattern does not match the registered pattern.
JP 7-21373 A JP-A-10-295664 JP-A-11-203452 JP 2004-178606 A JP 2004-62826 A

  However, in the above-described personal authentication device, since the image receiving element detects the light imaged by the image forming element, the subject must be separated from the image receiving element. Accordingly, since the subject needs to be separated from the image receiving element, external light is likely to be incident on the image receiving element, and the apparatus is liable to malfunction.

  In addition, since the imaging element and the image receiving element need to be separated from the focal length of the imaging element, it is difficult to reduce the size of the apparatus. In particular, it should be noted that it is necessary to downsize the personal authentication device, considering that the personal authentication device is mounted on the portable terminal.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an active sensor, a personal authentication device, a portable terminal, and a signal extraction method that can suppress the occurrence of malfunction due to incidence of external light or the like and can reduce the size of the device. And

  According to a first aspect of the present invention, there is provided a substrate having a placement surface facing a subject, a light emitting area provided on the placement surface, and emitting light toward the subject, and the placement surface. And a light receiving element that detects light reflected by the subject, and a light that is provided between the light emitting region and the light receiving element on the arrangement surface, and is made of a light-shielding material. The gist of the present invention is that the active sensor includes the separation body.

  According to this feature, the light emitting area and the light receiving element are provided on the same surface (arrangement surface) of the substrate, and no image receiving element such as a CCD or imaging element is used. The distance can be shortened. As a result, it is possible to suppress the occurrence of malfunction due to the incidence of external light or the like and to reduce the size of the active sensor. In addition, it is possible to reduce the size of a device on which an active sensor is mounted.

  In addition, since the light separating member is provided between the light emitting region and the light receiving element, the light separating member blocks noise light such as light reflected from an object that should not be detected by the light receiving element and external light. . This can suppress malfunction of the active sensor.

  According to a second feature of the present invention, in the first feature described above, the light receiving element is a phototransistor, and the phototransistor includes a control electrode provided on the arrangement surface, and a surface of the control electrode. A dielectric covering the first electrode provided on the arrangement surface, a second electrode provided on the arrangement surface, an intermediate electrode provided on the dielectric, and a side surface of the dielectric A first channel formation region is formed from the first electrode toward the intermediate electrode at the interface between the side surface of the dielectric and the semiconductor, and the intermediate The gist is that the second channel formation region is formed from the electrode toward the second electrode.

  According to a third feature of the present invention, in the first feature described above, the light receiving element is a phototransistor, and the phototransistor includes a control electrode provided on the arrangement surface, and a surface of the control electrode. A dielectric covering the semiconductor, a semiconductor covering the surface of the dielectric, a first electrode provided on the semiconductor, and a second electrode provided on the semiconductor, the dielectric and the semiconductor The gist is that a channel formation region is formed at the interface with the.

  According to a fourth feature of the present invention, in the first feature described above, the light receiving element is a two-terminal element, the two-terminal element is provided on the arrangement surface, and the first electrode. The gist is that the semiconductor device is configured by a semiconductor provided on the electrode and a second electrode provided on the semiconductor.

  According to a fifth feature of the present invention, in the first feature described above, the light receiving element is an organic solar cell, and the organic solar cell includes a first electrode provided on the arrangement surface, and the first electrode. The gist is to include at least a photoelectric conversion part provided on the electrode and a second electrode provided on the photoelectric conversion part.

  According to a sixth feature of the present invention, in the first feature described above, the base has a back surface provided on the opposite side of the arrangement surface, and a position corresponding to the light emitting region on the back surface. The gist of this is that a surface-emitting light source is provided on the surface.

  According to a seventh feature of the present invention, there is provided a personal authentication device having an active sensor array in which active sensors according to any of the first to sixth features described above are arranged in an array as personal identification information. A storage unit that stores registered feature values; an extraction unit that extracts feature values of the subject based on an output signal output from the active sensor; and a feature value stored in the storage unit and the extraction And a determination unit that compares the feature amount extracted by the unit and determines whether or not the subject is valid.

  According to an eighth aspect of the present invention, in the seventh aspect described above, the personal authentication device further includes a control unit that causes the light emitted from the light emitting area to blink according to a predetermined time-series pattern, and the active sensor includes The gist is to output the output signal in accordance with the predetermined time series pattern.

  According to a ninth feature of the present invention, in the seventh feature described above, the personal authentication device further includes a control unit that controls blinking of the light emitted from the light emitting region, and the control unit is a single active type. When turning on the light emitted from the light emitting area provided in the sensor, the light emitted from the light emitting area provided in another active sensor adjacent to the one active sensor is turned off. This is the gist.

  According to a tenth aspect of the present invention, there is provided a functional surface in which a portable terminal including the personal authentication device according to any one of the seventh to ninth characteristics is provided with an operation unit or a display unit. The present invention includes a housing having a gripping surface gripped by a user, and the active sensor is provided on the gripping surface.

  According to an eleventh feature of the present invention, there is provided a signal extraction method for extracting the feature amount of the subject using the active sensor according to any of the first to sixth features described above, from the light emitting region. Based on the step of blinking the emitted light according to a predetermined time series pattern, the step of the active sensor outputting an output signal according to the predetermined time series pattern, and the output signal output from the active sensor And a step of extracting a feature amount of the subject.

  According to the present invention, it is possible to provide an active sensor, a personal authentication device, a portable terminal, and a signal extraction method that can suppress the occurrence of malfunction due to incident external light or the like and can reduce the size of the device. .

  Hereinafter, an active sensor according to an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

  However, it should be noted that the drawings are schematic and ratios of dimensions are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[First Embodiment]
(Configuration of active sensor array)
The configuration of the active sensor array according to the first embodiment will be described below with reference to the drawings. FIG. 1 is a partially enlarged view showing a configuration of an active sensor array 100 according to the first embodiment.

  As shown in FIG. 1, the active sensor array 100 includes a plurality of active sensors 10 in which a light receiving element 20, a light source 30, and a light separator 40 are formed on a substrate 1.

  The light receiving element 20 is an element that detects light reflected by a subject (for example, a blood vessel of a user's hand (depth = 2 mm or so)). The light source 30 is a light source such as an organic EL element that emits light toward a subject (for example, JP-A-2005-239648). The light separator 40 is made of a light-shielding material.

  Here, it should be noted that the light separator 40 is provided at least between the light receiving element 20 and the light source 30 (light emitting region 30A described later). As shown in FIG. 1, the light separator 40 is preferably provided along the outer periphery of the light receiving element 20 so that noise light does not enter the light receiving element 20. The light separator 40 is preferably provided along the outer periphery of the light source 30 in order to reduce the directivity of the light source 30.

  The base 1 is provided with a wiring housing area 2 for housing wiring connected to the light receiving element 20 and the light source 30.

  Next, the configuration of the active sensor array according to the first embodiment will be further described with reference to the drawings. FIG. 2 is a partial cross-sectional view showing the active sensor array 100 according to the first embodiment.

  As shown in FIG. 2, the active sensor 10 includes a base 1, a light receiving element 20, a light source 30, and a light separator 40. Here, the pitch interval of the active sensor 10 is preferably 0.3 mm or less. The distance between the upper surface of the semiconductor 26 and the subject 200 is preferably about 2 mm to 4 mm.

  The base 1 has an arrangement surface 1A that faces the subject 200 (the subject 200A and the subject 200B). On the arrangement surface 1A, a light emission region 30A in which the light source 30 is arranged is provided.

  The light receiving element 20 is provided on the arrangement surface 1A adjacent to the light emitting region 30A, and includes a control electrode 21, a dielectric 22, a source electrode 23, a drain electrode 24, an intermediate electrode 25, and a semiconductor 26 ( A semiconductor 26A and a semiconductor 26B). In the first embodiment, the light receiving element 20 is a phototransistor.

  The control electrode 21 is provided on the arrangement surface 1A of the base 1. The control electrode 21 has a trapezoidal shape that decreases from the intermediate electrode 25 side toward the arrangement surface 1A side. The dielectric 22 covers the surface of the control electrode 21.

  The source electrode 23 and the drain electrode 24 are provided on the arrangement surface 1A of the base 1. The intermediate electrode 25 is provided on the upper surface of the control electrode 21. Here, the intermediate electrode 25 is made of a light-shielding material in order to prevent noise light from entering the semiconductor 26.

  The semiconductor 26 is provided on the side surface of the dielectric 22 and includes a semiconductor 26A and a semiconductor 26B.

  When a voltage is applied to the control electrode 21 at the interface between the side surface of the dielectric 22 and the semiconductor 26 </ b> A, a first channel formation region is formed from the source electrode 23 toward the intermediate electrode 25. On the other hand, when a voltage is applied to the control electrode 21 at the interface between the side surface of the dielectric 22 and the semiconductor 26 </ b> B, a second channel formation region is formed from the intermediate electrode 25 toward the drain electrode 24.

  Here, when a voltage is applied to the control electrode 21 and light emitted from the light source 30 is reflected by the subject 200 and enters the semiconductor 26 (in this case, the semiconductor 26A), the light is emitted from the source electrode 23 via the intermediate electrode 25. The value of the current flowing through the drain electrode 24 changes. In this way, the light receiving element 20 detects the presence / absence and distribution of the subject 200.

  The light source 30 includes an anode electrode 31 provided on the arrangement surface 1 </ b> A of the substrate 1, a light emitting layer 32 provided on the anode electrode 31, and a cathode electrode 33 provided on the light emitting layer 32.

  The light separator 40 is provided between the light receiving element 20 and the light emitting region 30A (light source 30) on the arrangement surface 1A of the base 1. The height and width of the light separator 40 are appropriately determined according to the distance between the base 1 and the subject 200, the pitch interval of the active sensor 10, and the like.

  For example, taking the active sensor 10A as an example, the height and width of the light separator 40 provided between the light receiving element 20 and the light emitting region 30A (light source 30) is determined by the light source 30 of the active sensor 10A. It is determined that the emitted light 5A is irradiated onto the subject 200A and the reflected light 6A reflected by the subject 200A is incident. On the other hand, the height and width of the light separator 40 are determined so that noise light such as reflected light 6B of light emitted from another active sensor 10 (active sensor 10B) or external light does not enter the semiconductor 26A. . Here, the width of the light separator 40 is preferably about 0.1 μm to 5 μm.

  The interval between the light separator 40 and the intermediate electrode 25 is appropriately determined according to the distance between the base 1 and the subject 200, the pitch interval of the active sensor 10, and the like.

  For example, taking the active sensor 10A as an example, the distance between the light separator 40 and the intermediate electrode 25 is such that the light reflected by the subject 200A (the reflected light 6A emitted from the light source 30 of the active sensor 10A) is a semiconductor. It is determined to be incident on 26A. On the other hand, the interval between the light separator 40 and the intermediate electrode 25 is determined so that noise light such as reflected light of external light emitted from other active sensors 10 and external light does not enter the semiconductor 26A. Here, the distance between the light separator 40 and the intermediate electrode 25 is preferably about 0.1 μm to 250 μm.

(Configuration of active sensor)
The configuration of the active sensor according to the first embodiment will be described below with reference to the drawings. FIG. 3 is a cross-sectional view showing the configuration of the active sensor 10 according to the first embodiment.

  As described above, the control electrode 21 has a trapezoidal shape that decreases from the intermediate electrode 25 side toward the arrangement surface 1A side. The angle α formed by the side surface of the control electrode 21 and the arrangement surface 1A is preferably about 60 ° to 89 °. In particular, the angle α is more preferably about 70 ° to 80 °.

  The length a from the bottom surface to the top surface of the control electrode 21 defines the channel lengths of the first channel formation region and the second channel formation region described above. Therefore, the length a is preferably about 10 nm to 10 μm. From the viewpoint of improving the operation speed of the light receiving element 20 and suppressing leakage current, the length a is more preferably about 0.1 μm to 1.5 μm.

  If the width b of the bottom surface of the control electrode 21 is small, the integration degree of the active sensor 10 is improved. On the other hand, if the width b of the bottom surface of the control electrode 21 is too small, it is difficult to form the control electrode 21. With this in mind, the width b of the bottom surface of the control electrode 21 is 0.1 μm to 5 μm from the viewpoint of improving the operation speed of the light receiving element 20 and suppressing electric resistance generated when a voltage is applied to the control electrode 21. It is preferable that it is a grade. Further, the width b of the bottom surface of the control electrode 21 is preferably not less than ½ of the length a from the bottom surface to the top surface of the control electrode 21.

(Materials for active sensors)
The material of the substrate 1 is not particularly limited as long as it can stably support the light receiving element 20 and the light source 30. For example, the material of the substrate 1 is a metal such as stainless steel, an alloy, glass, resin, paper, cloth, or the like.

  The light emitting layer 32 of the light source 30 is made of a group III-V (GaAs, InP, GaAlAs, etc.), II-VI (CdS / CdTe, Cu2S, ZnS, ZnSe, etc.), I-III-VI, organic It is a semiconductor and is not particularly limited. For example, as the light-emitting layer 32, a light-emitting layer containing “an organometallic compound including a quinoxaline structure” disclosed in JP-A-2005-239648 can be used.

  As a material of the dielectric 22 of the light receiving element 20, an inorganic material such as a silicon oxide film, a silicon nitride film, or a mixed film thereof can be used. The dielectric 22 is parylene, polycarbonate resin, polyvinyl acetal resin, polyester resin, modified ether type polyester resin, polyarylate resin, phenoxy resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, polystyrene resin, acrylic resin. And organic materials such as methacrylic resin, cellulose resin, urea resin, polyurethane resin, silicon resin, epoxy resin, polyamide resin, polyacrylamide resin, and polyvinyl alcohol resin, and copolymers thereof.

  The organic semiconductor material constituting the semiconductor 26 of the light receiving element 20 may be either a material having an electron accepting function or a material having an electron donating function.

  For example, materials having an electron-accepting function include oligomers and polymers having pyridine and its derivatives as a skeleton, oligomers and polymers having quinoline and its derivatives as a skeleton, ladder polymers using benzophenanthrolines and derivatives thereof, and cyano-polyphenylene. Low in polymers such as vinylene, fluorinated metal-free phthalocyanines, fluorinated metal phthalocyanines and derivatives thereof, perylene and derivatives thereof (gold CDA, gold CDI, etc.), naphthalene derivatives (NTCDA, NTCDI, etc.), bathocuproin and derivatives thereof It is a molecular organic compound.

  On the other hand, materials having an electron-donating function include oligomers and polymers having thiophene and its derivatives as skeletons, oligomers and polymers having phenylene-vinylene and its derivatives as skeletons, oligomers and polymers having fluorene and its derivatives as skeletons, and benzofurans. Oligomers and polymers having skeletons thereof, oligomers and polymers having thienylene-vinylene and derivatives thereof as skeletons, oligomers and polymers having aromatic tertiary amines such as triphenylamine and derivatives thereof as skeletons, carbazole and the like Oligomers and polymers having derivatives as skeletons, oligomers and polymers having vinylcarbazole and derivatives thereof as skeletons, oligomers and polymers having pyrrole and derivatives thereof as skeletons -Oligomers and polymers having acetylene and its derivatives as a skeleton, oligomers and polymers having isothiaphene and its derivatives as a skeleton, oligomers and polymers having heptadiene and its derivatives as a skeleton, metal-free phthalocyanines and metal phthalocyanines And derivatives thereof, diamines and phenyldiamines and derivatives thereof, acenes and derivatives thereof such as pentacene, porphyrin, tetramethylporphyrin, tetraphenylporphyrin, tetrabenzporphyrin, monoazotetrabenzporphyrin, diazotetrabenzporphine, Triazotetrabenzporphyrin, octaethylporphyrin, octaalkylthioporphyrazine, octaalkylaminoporphyrazine, hemipol Irajin, metal-free porphyrins, metal porphyrins, and derivatives thereof, such as chlorophyll, a low-molecular organic compounds such as cyanine dyes, merocyanine dyes, squarylium dyes, quinacridone dyes, azo dyes, anthraquinone, benzoquinone, quinone dyes naphthoquinone. As metal phthalocyanine and metal porphyrin central metals, magnesium, zinc, copper, silver, aluminum, silicon, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, tin, gold, lead and other metals, metal oxides, A metal halide or the like is used.

  As a material of the semiconductor 26 of the light receiving element 20, the above-described material may be used alone, or a material in which the above-described material is dispersed and mixed in an appropriate binder material may be used. Moreover, you may use the material which incorporated the low molecular organic compound mentioned above in the principal chain or side chain of a suitable high molecular organic compound. Examples of the above-described binder material or high molecular organic compound serving as the main chain include, for example, polycarbonate resin, polyvinyl acetal resin, polyester resin, modified ether type polyester resin, polyarylate resin, phenoxy resin, polyvinyl chloride resin, polyvinyl acetate resin. , Polyvinylidene chloride resin polystyrene resin, acrylic resin, methacrylic resin, cellulose resin, urea resin, polyurethane resin, silicon resin, epoxy resin, polyamide resin, polyacrylamide resin, polyvinyl alcohol resin, and their copolymers, or Photoconductive polymers such as polyvinyl carbazole and polysilane are used.

  The materials of the electrodes (control electrode 21, source electrode 23, drain electrode 24 and intermediate electrode 25) provided on the light receiving element 20 and the electrodes (anode electrode 31 and cathode electrode 33) provided on the light source 30 are gold, silver, A metal or an alloy such as aluminum, copper, tantalum, or titanium, a low-resistance semiconductor such as highly doped silicon, or an alloy such as metal silicide is used.

  When the electrodes provided on the light receiving element 20 and the light source 30 are used as transparent electrodes, the electrodes are made of, for example, metal oxides such as indium tin oxide (ITO), fluorine-doped tin oxide, zinc oxide, and tin oxide. Used. In addition, conductive high molecular organic compounds such as polyacetylene, polypyrrole, and polythiazyl may be used. The material of the electrode is also selected depending on the electrical properties (ohmic property, Schottky property, etc.) between the electrode and the semiconductor layer.

(Function and effect)
According to the active sensor 10 according to the first embodiment, the light source 30 (light emission region 30A) and the light receiving element 20 are provided on the same surface (arrangement surface 1A) of the base 1, and an image receiving element such as a CCD is provided. Since the child and the imaging element are not used, the distance between the light receiving element 20 and the subject 200 can be shortened. As a result, it is possible to suppress the occurrence of malfunction due to the incidence of external light or the like and to reduce the size of the active sensor 10. In addition, the device on which the active sensor 10 is mounted can be downsized.

  Further, since the light separator 40 is provided between the light source 30 (light emitting region 30A) and the light receiving element 20, light reflected by the subject 200 that should not be detected by the light receiving element 20 or external light, etc. The light separator 40 blocks the noise light. Thereby, malfunction of the active sensor 10 can be suppressed.

  According to the active sensor 10 according to the first embodiment, since the intermediate electrode 25 made of a light-shielding material is provided on the control electrode 21, the subject 200 that the light receiving element 20 should not detect. The intermediate electrode 25 blocks noise light such as reflected light and external light. Thereby, the malfunction of the active sensor 10 can be further suppressed.

  According to the active sensor 10 according to the first embodiment, the control electrode 21 has a trapezoidal shape that decreases from the intermediate electrode 25 side toward the arrangement surface 1A side. Therefore, since the width b of the bottom surface of the control electrode 21 is smaller than the width of the top surface, even if the source electrode 23 and the drain electrode 24 are provided on the arrangement surface 1A, the increase in the width of the light receiving element 20 can be suppressed. The integration degree of 10 increases. On the other hand, since the width of the upper surface of the control electrode 21 is larger than the width b of the bottom surface, even if the intermediate electrode 25 is a transparent electrode, it is difficult for noise light to enter the semiconductor 26 and the active sensor 10. Malfunction can be suppressed.

[Second Embodiment]
The second embodiment will be described below with reference to the drawings. In the following, differences between the first embodiment and the second embodiment described above will be mainly described.

  Specifically, the configuration of the phototransistor that is a light receiving element is different between the first embodiment and the second embodiment described above.

(Configuration of active sensor array)
The configuration of the active sensor array according to the second embodiment will be described below with reference to the drawings. FIG. 4 is a partial cross-sectional view showing an active sensor array 100 according to the second embodiment. In FIG. 4, it should be noted that the same components as those in FIG.

  As shown in FIG. 4, the light receiving element 120 includes a control electrode 121, a dielectric 122, a source electrode 123, a drain electrode 124, and a semiconductor 126.

  The control electrode 121 is provided on the arrangement surface 1A of the base 1. The dielectric 122 covers the surface of the control electrode 121. The source electrode 123 and the drain electrode 124 are provided on the upper surface of the semiconductor 126. The semiconductor 126 covers the dielectric 122. A channel formation region for connecting the source electrode 123 and the drain electrode 124 is formed at the interface between the dielectric 122 and the semiconductor 126 when a voltage is applied to the control electrode 121.

  Here, when the light emitted from the light source 30 is reflected by the subject 200 and enters the semiconductor 126 while the voltage is applied to the control electrode 121, the value of the current flowing from the source electrode 123 to the drain electrode 124 changes. In this way, the light receiving element 120 detects the presence / absence or distribution of the subject 200.

  It should be noted that the dielectric, semiconductor, and electrode materials provided in the light receiving element 120 are the same as those in the first embodiment described above. In addition, the light receiving elements disclosed in Japanese Patent Application Laid-Open Nos. 2005-302888 and 2003-282854 can be used.

(Function and effect)
According to the active sensor 10 according to the second embodiment, even if the light receiving element (phototransistor) has a configuration different from that of the above-described first embodiment, the same effects as those of the first embodiment can be obtained.

[Third Embodiment]
Hereinafter, a third embodiment will be described with reference to the drawings. In the following, differences between the first embodiment and the third embodiment described above will be mainly described.

  Specifically, in the first embodiment described above, the light receiving element is a phototransistor, but in the third embodiment, the light receiving element is a photodiode (two-terminal element).

(Configuration of active sensor array)
The configuration of the active sensor array according to the third embodiment will be described below with reference to the drawings. FIG. 5 is a partial cross-sectional view showing an active sensor array 100 according to the third embodiment. In FIG. 5, it should be noted that the same components as those in FIG.

  As shown in FIG. 5, the light receiving element 220 includes a first electrode 223, a second electrode 224 (second electrode 224 </ b> A and second electrode 224 </ b> B), and a semiconductor 226.

  The first electrode 223 is provided on the arrangement surface 1 </ b> A of the base 1. The second electrode 224 is provided on the upper surface of the semiconductor 226. The second electrode 224A and the second electrode 224B may be connected in a donut shape. The semiconductor 226 is provided on the first electrode 223.

  Here, when light emitted from the light source 30 is reflected by the subject 200 and enters the semiconductor 226, a current flows from the first electrode 223 to the second electrode 224. In this manner, the light receiving element 220 detects the presence / absence or distribution of the subject 200.

  It should be noted that the semiconductor and electrode materials provided in the light receiving element 220 are the same as those in the first embodiment. In addition, the light receiving elements disclosed in JP-A-6-29514 and JP-A-5-55610 can be used.

(Function and effect)
According to the active sensor 10 according to the third embodiment, even if the light receiving element is a photodiode, the same effect as in the first embodiment described above can be obtained.

[Fourth Embodiment]
Hereinafter, a fourth embodiment will be described with reference to the drawings. In the following, differences between the first embodiment and the fourth embodiment described above will be mainly described.

  Specifically, in the first embodiment described above, the light receiving element is a phototransistor, but in the fourth embodiment, the light receiving element is an organic solar cell.

(Configuration of active sensor array)
The configuration of the active sensor array according to the fourth embodiment will be described below with reference to the drawings. FIG. 6 is a partial cross-sectional view showing an active sensor array 100 according to the fourth embodiment. In FIG. 6, it should be noted that the same components as those in FIG.

  As shown in FIG. 6, the light receiving element 320 includes a first electrode 323, a second electrode 324 (second electrode 324A to second electrode 324C), and a semiconductor 326 (semiconductor 326A to semiconductor 326D).

  The first electrode 323 is provided on the arrangement surface 1 </ b> A of the base 1. For example, the first electrode 323 includes a gold vapor deposition film (thickness = 100 nm) formed on the arrangement surface 1A and a silver vapor deposition film (thickness = 100 nm) formed on the gold vapor deposition film. .

  The second electrode 324 is provided over the semiconductor 326D. For example, the second electrode 324A and the second electrode 324B (peripheral part) are gold vapor deposition films (thickness = 200 nm), and the second electrode 324C (window part) is a transparent electrode (thickness = thickness) made of ZnO or the like. 100 nm) or a thin deposited film of gold (thickness = 2 nm).

The semiconductor 326A is provided over the first electrode 323. For example, the semiconductor 326A is a deposited film (thickness = 10 nm) of an n-type conductive electron transport material (for example, 3,4,9,10-perylenetetracarboxylic dianhydride, fullerene C ₆₀ ). Note that as a material of the semiconductor 326A, a material similar to that of the semiconductor 326C described later may be used.

  The semiconductor 326B is provided over the semiconductor 326A. For example, the semiconductor 326B is a deposited film (thickness = 10 nm) of a hole-blocking electron transport material (for example, bathocuproine, 1,4,5,8-naphthalenetetracarboxylic dianhydride).

The semiconductor 326C is provided over the semiconductor 326B. For example, the semiconductor 326C is a deposited film (thickness = 20 nm) of the above-described material having an electron-accepting function or an n-type conductive electron transport material (for example, fullerene C ₆₀ , carbon nanotube, carbon nanohorn, perylene derivative). .

  The semiconductor 326D is provided over the semiconductor 326C. For example, the semiconductor 326D is a deposited film (thickness = 50 nm) of the above-described material having an electron donating function or a p-type conductive hole transport material (for example, a catacondensed aromatic compound such as rubrene or diphenylanthracene). .

  Note that the relationship between the thicknesses of the semiconductor 326B, the semiconductor 326C, and the semiconductor 326D preferably satisfies the relation of semiconductor 326D> semiconductor 326C ≧ semiconductor 326B as an empirical rule for improving the photoelectric conversion rate. It should be noted that the semiconductors 326B to 326D constitute a photoelectric conversion unit that converts light into current.

  Here, when light emitted from the light source 30 is reflected by the subject 200 and enters the photoelectric conversion unit (semiconductor 326B to semiconductor 326D), light having an open-circuit voltage of about 0.9 V between the first electrode 323 and the second electrode 324. An electromotive force is generated and current flows. In this way, the light receiving element 320 detects the presence / absence and distribution of the subject 200.

  Note that the configuration of the light receiving element 320 is not limited to the above-described configuration, and it is needless to say that the light receiving element 320 may be any organic solar cell. In particular, organic solar cells described in Japanese Patent Application No. 2006-217686, Japanese Patent Application No. 2006-267257, Japanese Patent Application No. 2006-267258, Japanese Patent Application No. 2006-320165, and the like can be suitably used.

(Function and effect)
According to the active sensor 10 according to the fourth embodiment, even if the light receiving element is an organic solar cell, the same effect as the first embodiment described above can be obtained.

[Fifth Embodiment]
Hereinafter, a fifth embodiment will be described with reference to the drawings. In the following, differences between the above-described third embodiment and the fifth embodiment will be mainly described.

  Specifically, in the above-described third embodiment, the active sensor array includes a light source for each active sensor 10, but in the fifth embodiment, the active sensor array includes a plurality of active sensors. 10 has a surface emitting light source shared by 10.

(Configuration of active sensor array)
The configuration of the active sensor array according to the fifth embodiment will be described below with reference to the drawings. FIG. 7 is a partial cross-sectional view showing an active sensor array 100 according to the fifth embodiment. In FIG. 7, it should be noted that the same components as those in FIG.

  As shown in FIG. 7, the active sensor array 100 includes a surface emitting light source 130 shared by a plurality of active sensors 10.

  The surface emitting light source 130 is provided on the back surface 1 </ b> B of the base 1, and includes an anode electrode 131, a light emitting layer 132, and a cathode electrode 133. Here, the first electrode 223 described above is made of a light-shielding material. Therefore, it should be noted that the light emitted from the surface light source 130 is emitted toward the subject 200 only from the light emission region 30 </ b> A because it is shielded by the first electrode 223.

  It should be noted that the material constituting the surface emitting light source 130 is the same as that in the first embodiment described above.

(Function and effect)
According to the active sensor array 100 according to the fifth embodiment, since the surface emitting light source 130 is shared by the plurality of active sensors 10, the active sensor array is compared with the case where a light source is provided for each active sensor 10. 100 manufacturing processes can be simplified. Moreover, the same effect as 1st Embodiment mentioned above can be acquired.

[Sixth Embodiment]
The sixth embodiment will be described below with reference to the drawings. In the following, a personal authentication device including the active sensor array shown in any of the first to fifth embodiments will be described.

(Configuration of active sensor array)
The configuration of the active sensor array according to the sixth embodiment will be described below with reference to the drawings. FIG. 8 is a plan view showing an active sensor array 100 according to the sixth embodiment. It should be noted that the active sensor array 100 shown in FIG. 8 has the same configuration as the active sensor array 100 shown in the first embodiment or the second embodiment.

  As shown in FIG. 8, in the active sensor array 100, a plurality of active sensors 10 are arranged in an array. In the active sensor array 100 according to the sixth embodiment, the active sensors 10 are arranged on a matrix with 5 columns × 6 rows.

(Function block of personal authentication device)
Hereinafter, functional blocks of the personal authentication device according to the sixth embodiment will be described with reference to the drawings. FIG. 9 is a block diagram showing a personal authentication device 500 according to the sixth embodiment.

  As shown in FIG. 9, the personal authentication device 500 includes a control pattern storage unit 510, a light source control unit 520, a light receiving element control unit 530, a signal acquisition unit 540, a feature amount extraction unit 550, and a personal identification information storage. Part 560 and authentication part 570.

  The control pattern storage unit 510 stores a blinking pattern of the light source 30 and an ON / OFF pattern of the light receiving element 20 (or the light receiving element 120).

  Here, as the blinking pattern and the ON / OFF pattern, the light source 30 and the light receiving element 20 (or the light receiving element 120) are temporally controlled, and the light source 30 and the light receiving element 20 (or the light receiving element 120) are spatially controlled. Pattern to do. Details of temporal control and spatial control will be described later.

  The light source control unit 520 switches the light source 30 on and off individually according to the blinking pattern stored in the control pattern storage unit 510.

  The light receiving element control unit 530 individually switches ON and OFF of the light receiving element 20 (or the light receiving element 120) according to the ON / OFF pattern stored in the control pattern storage unit 510. Specifically, the light receiving element control unit 530 switches the light receiving element 20 (or the light receiving element 120) to ON by applying a voltage to the control electrode 21, and does not apply a voltage to the control electrode 21, thereby receiving the light receiving element. 20 (or the light receiving element 120) is switched to OFF.

  The signal acquisition unit 540 acquires a signal detected by the light receiving element 20 (or the light receiving element 120). The signal detected by the light receiving element 20 (or the light receiving element 120) is a signal indicating the presence and distribution of the subject 200 (for example, blood vessels in the hand).

  The feature amount extraction unit 550 extracts the feature amount of the subject 200 based on the signal detected by the signal acquisition unit 540.

  The personal identification information storage unit 560 stores a feature amount registered in advance as personal identification information for identifying an individual.

  The authentication unit 570 compares the feature amount extracted by the feature amount extraction unit 550 with the feature amount stored in the personal identification information storage unit 560 to authenticate whether the subject 200 (individual) is valid. To do. For example, when the difference between the feature amount extracted by the feature amount extraction unit 550 and the feature amount stored in the personal identification information storage unit 560 is within a predetermined threshold, the authentication unit 570 determines that the subject 200 (individual) Is determined to be valid. On the other hand, the authentication unit 570 determines that the subject 200 (individual) is not valid when the above-described difference exceeds a predetermined threshold.

(Spatial control)
Hereinafter, the spatial control described above will be described. In the spatial control, the light receiving element 20 provided in one active sensor 10 changes the reflected light of the light emitted from the light source 30 provided in another active sensor 10 adjacent to the one active sensor 10 to the noise light. It is performed for the purpose of suppressing the detection.

  Specifically, the blinking pattern in the spatial control is a pattern in which the light source 30 provided in another active sensor 10 is turned off when the light source 30 provided in one active sensor 10 is turned on. is there. Here, it is assumed that the ON / OFF pattern of the light receiving element 20 is synchronized with the blinking pattern.

  For example, in the active sensor array 100 shown in FIG. 8, the personal authentication device 500 has the even columns and even rows when the light sources 30 provided in the active sensors 10 in the odd columns and odd rows are lit. The light source 30 provided in the active sensor 10 is turned off. On the other hand, the personal authentication device 500 uses the light sources 30 provided in the active sensors 10 in the odd columns and the odd rows when the light sources 30 provided in the active sensors 10 in the even columns and the even rows are turned on. Turns off.

  It should be noted that the active sensor array 100 may switch on / off the light source 30 in units of columns or rows.

  For example, in the active sensor array 100 shown in FIG. 8, the personal authentication device 500 is provided in the even-numbered active sensors 10 when the light sources 30 provided in the odd-numbered active sensors 10 are lit. The light source 30 may be turned off. The personal authentication device 500 may turn off the light sources 30 provided in the even-numbered active sensors 10 when the light sources 30 provided in the odd-numbered active sensors 10 are turned on.

(Time control)
Hereinafter, the above-described temporal control will be described with reference to FIG. The temporal control is performed for the purpose of removing noise light (noise signal) detected by the light receiving element 20 provided in the active sensor 10.

  Specifically, the blinking pattern (time series pattern) in the temporal control is a pattern for controlling blinking of the light source 30 on the time axis.

For example, as illustrated in FIG. 10A, the light source 30 is turned _{on for a} predetermined lighting time (t _on ) at time t ₁ and time t ₂ and is turned off for a predetermined lighting time (t _off ) at other times.

As shown in FIG. 10 (b), the light receiving element 20 is not only a time t ₁ and time t _2, the also detects the signal at other times. Therefore, the light receiving element 20 detects noise signals (n _{1 to} n ₃ ).

As shown in FIG. 10C, the active sensor 10 outputs only the signals (output signal s ₁ and output signal s ₂ ) detected at time t ₁ and time t ₂ .

  Here, the noise signal may be removed by multiplying the detection signal shown in FIG. 10B by the blinking pattern shown in FIG. Alternatively, the noise signal may be removed by synchronizing the blinking pattern and the ON / OFF pattern and applying a voltage to the control electrode 21 so that the light receiving element 20 is turned on only during the lighting time.

Incidentally, if the duty ratio _{(t on / t on + t} off) is 0.2 or less, even when used outdoors, rejection of the noise signal can be sufficiently obtained. Further, the duty ratio _{(t on / t on + t} off) is preferably about 0.05 to 0.15. Moreover, in order to shorten the waiting time until an output signal is obtained from the active sensor 10, the lighting cycle (t _on + t _off ) is preferably 0.2 seconds or less.

  The blinking pattern may be a pattern for switching on / off of the light source 30 at a frequency of about 5 Hz, or a pattern for switching on / off of the light source 30 according to a predetermined code (bit sequence). As the predetermined code, it is preferable to use a code longer than 10 bits in order to improve pattern identification accuracy.

(Function and effect)
According to the personal authentication device 500 according to the sixth embodiment, the light receiving element 20 is effectively suppressed from detecting noise light (noise signal) by controlling the blinking pattern of the light source 30 by spatial control. Can do. Further, by controlling the blinking pattern of the light source 30 by temporal control, the noise light (noise signal) detected by the light receiving element 20 can be removed.

[Seventh Embodiment]
Hereinafter, a seventh embodiment will be described with reference to the drawings. In the following, a portable terminal to which a personal authentication device including the active sensor array shown in any of the first to fifth embodiments is applied will be described.

(Configuration of mobile device)
The configuration of the mobile terminal according to the seventh embodiment will be described below with reference to the drawings. FIG.11 and FIG.12 is a figure which shows the portable terminal 600 which concerns on 7th Embodiment. As illustrated in FIG. 11, the mobile terminal 600 includes a housing 610 having a plurality of keys 611 and a housing 620 having a display unit 621.

  As shown in FIG. 12, the housing 610 has a key arrangement surface 631 (functional surface) provided with a plurality of keys 611, and a gripping surface (bottom surface 632A, side surface 632B) that is a surface gripped by the user. .

  The active sensor array 100 described above is provided on the bottom surface 632A and the side surface 632B. The active sensor array 100 may be provided only on the bottom surface 632A.

(Function and effect)
According to the mobile terminal 600 according to the seventh embodiment, since the active sensor array 100 is provided on the gripping surfaces (the bottom surface 632A and the side surface 632B) that are surfaces gripped by the user, the user uses the mobile terminal 600. Personal authentication can be performed simply by gripping, improving user convenience.

[Other Embodiments]
Although the present invention has been described with reference to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, in the active sensor array 100 shown in the fifth embodiment, the light receiving element shown in the third embodiment and the surface-emitting light source 130 are combined, but the present invention is not limited to this. Specifically, the light receiving element and the surface emitting light source 130 shown in the first embodiment, the second embodiment, and the fourth embodiment may be combined.

  In the fourth embodiment described above, the light receiving element 320 includes the semiconductor 326A. However, the present invention is not limited to this, and the semiconductor 326A may not be included.

  In 6th Embodiment mentioned above, although the personal authentication apparatus 500 which has the active sensor array 100 shown in 1st Embodiment and 2nd Embodiment was illustrated, it is not limited to this. Specifically, the personal authentication device 500 may include the active sensor array 100 shown in the third embodiment and the fourth embodiment. In this case, since the ON / OFF of the light receiving element cannot be controlled, the light receiving element control unit 530 becomes unnecessary. However, it should be noted that the temporal control described above can be performed because it is not necessary to control ON / OFF of the light receiving element. In addition, a switch that switches ON / OFF of each light receiving element may be provided in the signal acquisition unit 540.

  In 7th Embodiment mentioned above, although the foldable mobile phone was illustrated as a portable terminal, it is not limited to this. Specifically, the mobile terminal may be a mobile phone in which a display unit and a key are provided on the same surface of the housing. The mobile terminal may be an information processing terminal such as a PDA, an IC card, a credit card, or the like.

1 is a partially enlarged view showing a configuration of an active sensor array 100 according to a first embodiment. 1 is a partial cross-sectional view showing an active sensor array 100 according to a first embodiment. 1 is a cross-sectional view showing an active sensor 10 according to a first embodiment. It is a partial cross section figure showing active type sensor array 100 concerning a 2nd embodiment. It is a partial cross section figure showing active type sensor array 100 concerning a 3rd embodiment. It is a partial cross section figure showing active type sensor array 100 concerning a 4th embodiment. It is a partial cross section figure showing active type sensor array 100 concerning a 5th embodiment. It is a top view which shows the active sensor array 100 which concerns on 6th Embodiment. It is a block diagram which shows the personal authentication apparatus 500 which concerns on 6th Embodiment. It is a figure which shows an example of the temporal control which concerns on 6th Embodiment. It is a figure which shows the portable terminal 600 which concerns on 7th Embodiment. It is a figure which shows the portable terminal 600 which concerns on 7th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Base | substrate, 1A ... Arrangement | positioning surface, 1B ... Back surface, 2 ... Wiring accommodation area | region, 10 ... Active type sensor, 20 ... Light receiving element, 21 ... Control electrode, 22 ... Dielectric material, 23 ... Source electrode, 24 ... Drain electrode, 25 ... Intermediate electrode, 26 ... Semiconductor, 30 ... Light source, 30A ... Light emitting region, 31 ... Anode electrode, 32... Luminescent layer, 33... Cathode electrode, 40... Light separator, 100... Active sensor array, 120. ... Dielectric material, 123 ... Source electrode, 124 ... Drain electrode, 126 ... Semiconductor, 130 ... Surface emitting light source, 131 ... Anode electrode, 132 ... Light emitting layer, 133 ... ..Cathode electrode, 200 ... subject, 220 ... light receiving element, 223 ... first Pole, 224, second electrode, 226, semiconductor, 320, light receiving element, 323, first electrode, 324, second electrode, 326, semiconductor, 500, individual Authentication device 510... Control pattern storage unit 520... Light source control unit 530... Light receiving element control unit 540... Signal acquisition unit 550. Personal identification information storage unit, 570 ... authentication unit, 600 ... mobile terminal, 610 ... casing, 611 ... key, 620 ... casing, 621 ... display unit, 631 ... Key arrangement surface, 632A ... bottom surface, 632B ... side surface

Claims (11)

A substrate having an arrangement surface facing the subject;
A light emitting area provided on the arrangement surface and emitting light toward the subject; and
A light receiving element that is provided on the arrangement surface and detects light reflected by the subject;
An active sensor, comprising: a light separator that is provided between the light emitting region and the light receiving element on the arrangement surface and is made of a light shielding material. The light receiving element is a phototransistor,
The phototransistor includes a control electrode provided on the arrangement surface, a dielectric covering a surface of the control electrode, a first electrode provided on the arrangement surface, and a first electrode provided on the arrangement surface. Two electrodes, an intermediate electrode provided on the dielectric, and a semiconductor provided along a side surface of the dielectric,
A first channel formation region formed from the first electrode toward the intermediate electrode and an intermediate electrode formed from the intermediate electrode toward the second electrode are formed at an interface between the side surface of the dielectric and the semiconductor. The active sensor according to claim 1, wherein a two-channel formation region is formed. The light receiving element is a phototransistor,
The phototransistor includes a control electrode provided on the arrangement surface, a dielectric covering the surface of the control electrode, a semiconductor covering the surface of the dielectric, a first electrode provided on the semiconductor, A second electrode provided on the semiconductor,
The active sensor according to claim 1, wherein a channel formation region is formed at an interface between the dielectric and the semiconductor. The light receiving element is a two-terminal element,
The two-terminal element includes a first electrode provided on the arrangement surface, a semiconductor provided on the first electrode, and a second electrode provided on the semiconductor. The active sensor according to claim 1. The light receiving element is an organic solar cell,
The organic solar cell includes at least a first electrode provided on the arrangement surface, a photoelectric conversion unit provided on the first electrode, and a second electrode provided on the photoelectric conversion unit. The active sensor according to claim 1. The base body has a back surface provided on the opposite side of the arrangement surface,
2. The active sensor according to claim 1, wherein a surface emitting light source is provided on the back surface at a position corresponding to the light emitting region. A personal authentication device having an active sensor array in which the active sensors according to any one of claims 1 to 6 are arranged in an array,
A storage unit for storing a feature amount registered as personal identification information;
An extraction unit that extracts a feature amount of the subject based on an output signal output from the active sensor;
A personal authentication device comprising: a determination unit that compares the feature amount stored in the storage unit with the feature amount extracted by the extraction unit to determine whether the subject is valid . A control unit that blinks the light emitted from the light emitting region according to a predetermined time-series pattern;
The personal authentication apparatus according to claim 7, wherein the active sensor outputs the output signal according to the predetermined time series pattern. A control unit for controlling blinking of light emitted from the light emitting region;
The controller emits the light emitted from another active sensor adjacent to the one active sensor when lighting the light emitted from the light emitting area provided in the one active sensor. The personal authentication device according to claim 7, wherein the light emitted from the area is turned off. A portable terminal comprising the personal authentication device according to any one of claims 7 to 9,
A housing having a functional surface, which is a surface provided with an operation unit or a display unit, and a gripping surface gripped by a user;
The mobile terminal according to claim 1, wherein the active sensor is provided on the gripping surface. A signal extraction method for extracting a feature amount of the subject using the active sensor according to claim 1,
Flashing the light emitted from the light emitting area according to a predetermined time-series pattern;
The active sensor outputting an output signal according to the predetermined time-series pattern;
Extracting the feature amount of the subject based on the output signal output from the active sensor.

Images