Detection device

Abstract

This detection device comprises: a sensor unit that includes a plurality of optical sensors which are disposed two-dimensionally; and an acquisition unit for acquiring the pattern of blood vessels in a human finger which is included in a light / dark pattern of light detected by the sensor unit. On the basis of the light / dark pattern, the acquisition unit acquires information pertaining to a pressing force from the finger toward the sensor unit.

Description

Detection device

[0001] The present disclosure relates to a detection device.

[0002] A mechanism is known in which blood vessels in a human finger are detected by an optical sensor that detects light while the finger is pressed against the optical sensor (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2004-265269

[0004] When detecting blood vessels in a finger, it is known that if the pressure of the finger on the optical sensor is too strong, the image of the blood vessels will become faint. Therefore, when the pressure of the finger on the optical sensor is too strong, it is desirable to detect this and provide feedback to the user who is pressing their finger against the optical sensor. However, in order to achieve such feedback with a conventional configuration, it is first necessary to provide a dedicated pressure sensor to detect the pressure of the finger on the optical sensor, which leads to problems such as an increase in parts and costs.

[0005] The present disclosure has been made in view of the above-mentioned problems, and aims to provide a detection device that can acquire information about the pressure from a finger without providing a dedicated pressure sensor.

[0006] A detection device according to one aspect of the present disclosure includes a sensor unit having a plurality of optical sensors arranged two-dimensionally, and an acquisition unit that acquires a pattern of blood vessels in a human finger contained in a light and dark pattern of light detected by the sensor unit, and the acquisition unit acquires information regarding the pressure force from the finger directed toward the sensor unit based on the light and dark pattern.

[0007] FIG. 1 is a block diagram showing an example of the main configuration of a detection device. FIG. 2 is a schematic diagram showing the positional relationship between a sensor module, a light source unit, and their peripheral configuration, and blood vessels in a finger that are the target of detection by the sensor module. FIG. 3 is a plan view showing an example of the sensor module, the light source unit, and the configuration connected thereto. FIG. 4 is a block diagram showing a more detailed example of the functional configuration of the configuration shown in FIG. 3. FIG. 5 is a circuit diagram showing a sensor module. FIG. 6 is a circuit diagram showing multiple partial detection areas. FIG. 7 is a schematic diagram showing the relationship between the degree of pressure applied from a finger to the sensor unit and the sensing result by the sensor unit. FIG. 8 is a schematic diagram showing a case where a change in the range occupied by a dark area in the sensing result corresponds to movement. FIG. 9 is a schematic diagram showing a case where a change in the range occupied by a dark area in the sensing result corresponds to enlargement. FIG. 10 is a flowchart showing the processing flow of the detection device, including determining and notifying that the pressure from the finger to the sensor unit is too strong. FIG. 11 is a block diagram showing an example of the main configuration of a detection device according to a modified example. FIG. 12 is a schematic diagram showing the positional relationship between the sensor module, light source unit, operating unit and their peripheral configuration in a detection device according to a modified example, and the blood vessels of a finger that are the object to be detected by the sensor module.

[0008] Each embodiment of the present disclosure will be described below with reference to the drawings. The disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the invention are naturally included within the scope of the present disclosure. Furthermore, to clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this specification and each drawing, elements similar to those described above with reference to the previous drawings will be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0009] 1 is a block diagram showing an example of the main configuration of a detection device 100 according to an embodiment. The detection device 100 includes a sensor module 1, a light source unit 5, an AFE 91, a control unit 92, a storage unit 93, a notification unit 94, and a communication unit 95. The sensor module 1 is configured to be able to detect light. The light source unit 5 is a light source that emits light of a wavelength that can be detected by the sensor module 1. Note that the AFE 91 denotes an analog front end.

[0010] Fig. 2 is a schematic diagram showing the positional relationship between the sensor module 1, the light source unit 5, and their peripheral configuration, and the blood vessels Ve of the finger Fi that are the object to be detected by the sensor module 1. As shown in Fig. 2, the light source unit 5 has, for example, a first light source substrate 51 and a second light source substrate 52. The specific configuration example of the light source unit 5 shown in Fig. 2 is merely an example and is not limited thereto. For example, the light source unit 5 may have one of the first light source substrate 51 or the second light source substrate 52 and a light source provided on that one, or may have three or more light source substrates and light sources provided on the light source substrates.

[0011] The sensor unit 10 of the sensor module 1 faces the light source unit 5 across the finger Fi. Light from light sources (e.g., a first light source 61 and a second light source 62, described below) provided in the light source unit 5 is partially blocked and absorbed by the finger Fi and the blood vessels Ve within the finger Fi, but the light that is not blocked or absorbed is detected by a photodiode PD provided in the sensor unit 10. Here, there is a difference in the degree of light blocking and absorption between the blood vessels Ve and the other parts of the finger Fi. This difference creates a contrast between the blood vessels Ve and the other parts of the finger Fi. The detection device 100 visualizes this contrast through light detection by the sensor module 1, thereby enabling pattern detection of the blood vessels Ve.

[0012] 2, a louver 99 is provided between the sensor module 1 and the finger Fi. The louver 99 is, for example, a light-blocking member provided with a plurality of light-guiding holes that penetrate in the opposing direction of the finger Fi and the sensor unit 10, and acts to limit the traveling direction of light passing between the finger Fi and the sensor unit 10 to the opposing direction of the finger Fi and the sensor unit 10.

[0013] 2 , the light source unit 5 is supported by a light-shielding member 98 on the opposite side of the sensor unit 10 with the finger Fi sandwiched therebetween. The light-shielding member 98 is a cover-like member that covers the detection surface of the sensor unit 10 so that light other than light emitted from the light source unit 5 does not enter the sensor unit 10. The light source unit 5 is provided on the sensor unit 10 side (one surface side) of the light-shielding member 98. In the example shown in FIG. 2 , a notification unit 94 is provided on the light-shielding member 98. The notification unit 94 is provided on the other surface side of the light-shielding member 98. To a user who inserts their finger Fi between the light source unit 5 and the sensor unit 10, the notification unit 94 appears to be provided on the light-shielding member 98.

[0014] The sensor module 1 and the light source unit 5 will be described below with reference to FIGS.

[0015] 3 is a plan view showing an example of the sensor module 1, the light source unit 5, and a configuration connected thereto. As shown in FIG. 3, the sensor module 1 includes a sensor substrate 21, a sensor unit 10, a gate line driving circuit 15, a signal line selection circuit 16, an AFE 91, a control circuit 122, a power supply circuit 123, a first light source substrate 51, a second light source substrate 52, at least one first light source 61, and at least one second light source 62. Note that, although the embodiment illustrates multiple types of light sources (the first light source 61 and the second light source 62) as examples of the light source, a single type of light source may be used.

[0016] A control board 121 is electrically connected to the sensor substrate 21 via a flexible printed circuit board 71. The flexible printed circuit board 71 is provided with an AFE 91. The control board 121 is provided with a control circuit 122 and a power supply circuit 123. The control circuit 122 is, for example, an FPGA (Field Programmable Gate Array). The control circuit 122 supplies control signals to the sensor unit 10, the gate line driving circuit 15, and the signal line selection circuit 16 to control the detection operation of the sensor unit 10. The control circuit 122 also supplies control signals to the first light source 61 and the second light source 62 to control the lighting or non-lighting of the first light source 61 and the second light source 62. The power supply circuit 123 also supplies voltage signals, such as a sensor power supply signal VDDSNS (see FIG. 6 ), to the sensor unit 10, the gate line driving circuit 15, and the signal line selection circuit 16. The power supply circuit 123 also supplies a power supply voltage to the first light source 61 and the second light source 62 under the control of the AFE 91.

[0017] The sensor substrate 21 has a detection area AA and a peripheral area GA. The detection area AA is an area where multiple photodiodes PD (see FIG. 6) of the sensor unit 10 are provided. The peripheral area GA is an area between the outer periphery of the detection area AA and the edge of the sensor substrate 21, and is an area that does not overlap with the photodiodes PD.

[0018] The gate line driving circuit 15 and the signal line selection circuit 16 are provided in the peripheral area GA. Specifically, the gate line driving circuit 15 is provided in a region of the peripheral area GA extending along the second direction Dy. The signal line selection circuit 16 is provided in a region of the peripheral area GA extending along the first direction Dx, and is provided between the sensor unit 10 and the AFE 91.

[0019] The first direction Dx is a direction in a plane parallel to the sensor substrate 21. The second direction Dy is a direction in a plane parallel to the sensor substrate 21 and is a direction perpendicular to the first direction Dx. The second direction Dy may intersect with the first direction Dx without being perpendicular to it. The third direction Dz is a direction perpendicular to the first direction Dx and the second direction Dy and is a normal direction of the sensor substrate 21.

[0020] The plurality of first light sources 61 are provided on the first light source substrate 51 and arranged along the second direction Dy. The plurality of second light sources 62 are provided on the second light source substrate 52 and arranged along the second direction Dy. The first light source substrate 51 and the second light source substrate 52 are electrically connected to the control circuit 122 and the power supply circuit 123 via terminals 124 and 125 provided on the control board 121, respectively.

[0021] The plurality of first light sources 61 and the plurality of second light sources 62 may be, for example, inorganic light-emitting diodes (LEDs) or organic light-emitting diodes (OLEDs). The plurality of first light sources 61 and the plurality of second light sources 62 emit first light L61 (see FIG. 38 ) and second light L62 (see FIG. 31 , etc.), respectively, having different wavelengths. The first light L61 and the second light L62 each have a different maximum emission wavelength. The maximum emission wavelength is the wavelength that exhibits the maximum emission intensity in an emission spectrum that shows the relationship between the wavelength and emission intensity of each of the first light L61 and the second light L62. Hereinafter, when a numerical value for a wavelength is simply stated, it is assumed to indicate the assumed maximum emission wavelength.

[0022] The first light L61 emitted from the first light source 61 is mainly reflected by the surface of the object to be detected, such as a finger Fg, and enters the sensor unit 10. This allows the sensor unit 10 to detect a fingerprint by detecting the shape of the projections and recesses on the surface of the finger Fg. The second light L62 emitted from the second light source 62 is mainly reflected by the inside of the finger Fg or passes through the finger Fg and enters the sensor unit 10. This allows the sensor unit 10 to detect information about the living body inside the finger Fg. The information about the living body includes, for example, the pulse wave, pulse rate, and blood vessel image of the finger Fg or palm.

[0023] As an example, the first light L61 may have a wavelength of 520 nm or more and 600 nm or less, and the second light L62 may have a wavelength of 780 nm or more and 900 nm or less, for example, approximately 850 nm. In this case, the first light L61 is blue or green visible light, and the second light L62 is infrared light. The sensor unit 10 can detect a fingerprint based on the first light L61 emitted from the first light source 61. The second light L62 emitted from the second light source 62 is reflected from the inside of the detection object, such as a finger Fg, or transmitted through or absorbed by the finger Fg, and then enters the sensor unit 10. This allows the sensor unit 10 to detect a pulse wave or a blood vessel image (blood vessel pattern) as information about the living body inside the finger Fg, etc.

[0024] Alternatively, the first light L61 may have a wavelength of 600 nm or more and 700 nm or less, for example, approximately 660 nm, and the second light L62 may have a wavelength of 780 nm or more and 900 nm or less, for example, approximately 850 nm. In this case, the sensor unit 10 can detect information about the living body, such as pulse waves, pulse rates, and blood vessel images, as well as blood oxygen saturation, based on the first light L61 emitted from the first light source 61 and the second light L62 emitted from the second light source 62. In this way, the detection device 100 includes the first light source 61 and multiple second light sources 62, and thus can detect various pieces of information about the living body by performing detection based on the first light L61 and detection based on the second light L62.

[0025] The arrangement of the first light sources 61 and the second light sources 62 shown in FIG. 3 is merely an example and can be modified as appropriate. For example, a plurality of first light sources 61 and a plurality of second light sources 62 may be arranged on each of the first light source substrate 51 and the second light source substrate 52. In this case, a group including a plurality of first light sources 61 and a group including a plurality of second light sources 62 may be arranged side by side in the second direction Dy, or the first light sources 61 and the second light sources 62 may be arranged alternately in the second direction Dy. Furthermore, the number of light source substrates on which the first light sources 61 and the second light sources 62 are provided may be one or three or more. Furthermore, only one of the first light source 61 or the second light source 62 may be provided. However, when it is expected to acquire a pattern of blood vessels Ve of a finger Fi as in the embodiment, it is desirable to provide a light source that emits light including infrared light. Furthermore, it is more desirable for the infrared light to be infrared light with a wavelength closer to visible light, so-called near-infrared light.

[0026] Fig. 4 is a block diagram showing a more detailed example of the functional configuration of the configuration shown in Fig. 3. As shown in Fig. 4, the sensor module 1 further includes a detection control unit 11 and a detection unit 40. Some or all of the functions of the detection control unit 11 are included in a control circuit 122. In addition, some or all of the functions of the detection unit 40 other than the AFE 91 are included in the control circuit 122.

[0027] The sensor unit 10 is an optical sensor having a photodiode PD, which is a photoelectric conversion element. The photodiode PD of the sensor unit 10 outputs an electrical signal corresponding to the incident light to the signal line selection circuit 16. The signal line selection circuit 16 sequentially selects the signal lines SGL in accordance with a selection signal ASW from the detection control unit 11. As a result, the electrical signal is output to the detection unit 40 as a detection signal Vdet. The sensor unit 10 also performs detection in accordance with a gate drive signal Vgcl supplied from the gate line drive circuit 15.

[0028] The detection control unit 11 is a circuit that supplies control signals to the gate line driving circuit 15, the signal line selection circuit 16, and the detection unit 40, respectively, and controls their operations. The detection control unit 11 supplies various control signals, such as a start signal STV, a clock signal CK, and a reset signal RST1, to the gate line driving circuit 15. The detection control unit 11 also supplies various control signals, such as a selection signal ASW, to the signal line selection circuit 16. The detection control unit 11 also supplies various control signals to the first light source 61 and the second light source 62, and controls the lighting and non-lighting of each.

[0029] The gate line driving circuit 15 is a circuit that drives a plurality of gate lines GCL (see FIG. 5) based on various control signals. The gate line driving circuit 15 sequentially or simultaneously selects the plurality of gate lines GCL and supplies a gate driving signal Vgcl to the selected gate lines GCL. In this way, the gate line driving circuit 15 selects a plurality of photodiodes PD connected to the gate lines GCL.

[0030] The signal line selection circuit 16 is a switch circuit that sequentially or simultaneously selects a plurality of signal lines SGL (see FIG. 5 ). The signal line selection circuit 16 is, for example, a multiplexer. The signal line selection circuit 16 connects the selected signal line SGL to the AFE 91 based on a selection signal ASW supplied from the detection control unit 11. As a result, the signal line selection circuit 16 outputs a detection signal Vdet of the photodiode PD to the detection unit 40.

[0031] The detection unit 40 includes an AFE 91, a signal processing unit 44, a storage unit 93, a detection timing control unit 47, and an output processing unit 50. The detection timing control unit 47 controls the AFE 91 and the signal processing unit 44 to operate in synchronization with each other based on a control signal supplied from the detection control unit 11.

[0032] The AFE 91 is a signal processing circuit that has the functions of, for example, a detection signal amplifier 42 and an A / D converter 43. The detection signal amplifier 42 amplifies the detection signal Vdet. The A / D converter 43 converts the analog signal output from the detection signal amplifier 42 into a digital signal.

[0033] The signal processing unit 44 is a logic circuit that detects a predetermined physical quantity input to the sensor unit 10 based on the output signal of the AFE 91. When the finger Fg is in contact with or in proximity to the detection area AA, the signal processing unit 44 can detect the unevenness of the surface of the finger Fg or palm based on the signal from the AFE 91. The signal processing unit 44 can also detect information about the living body based on the signal from the AFE 91. The information about the living body includes, for example, blood vessel images of the finger Fg or palm, pulse waves, pulse rate, blood oxygen saturation, etc.

[0034] When acquiring the blood oxygen saturation of a human, for example, 660 nm (within the range of 500 nm to 700 nm) is used as the first light L61, and approximately 850 nm (within the range of 800 nm to 930 nm) is used as the second light L62. Since the amount of light absorption varies depending on the amount of oxygen absorbed by hemoglobin, the amount of light obtained by subtracting the amount of light absorbed by the blood (hemoglobin) from the amount of the irradiated first light L61 and second light L62 is detected by the photodiode PD. Most of the oxygen in the blood is reversibly bound to hemoglobin in red blood cells, with only a small portion dissolved in the plasma. More specifically, the percentage of oxygen bound to the blood's overall capacity is used as the oxygen saturation (SpO ２ The blood oxygen saturation can be calculated from the amount of light absorbed by the blood (hemoglobin) minus the amount of light irradiated using the two wavelengths of the first light L61 and the second light L62.

[0035] The signal processing unit 44 may also acquire detection signals Vdet (information about the living body) simultaneously detected by a plurality of photodiodes PD and average these signals. In this case, the detection unit 40 can suppress measurement errors caused by noise and a relative positional shift between the sensor unit 10 and the object to be detected, such as a finger Fg, thereby enabling stable detection.

[0036] The storage unit 93 temporarily stores the signals calculated by the signal processing unit 44. The storage unit 93 may be, for example, a RAM (Random Access Memory), a register circuit, or the like.

[0037] The output processing unit 50 functions as a processing unit that performs processing based on outputs from the multiple photodiodes PD. Specifically, the output processing unit 50 of the embodiment outputs a sensor output Vo that includes at least pulse wave data based on at least the detection signal Vdet acquired via the signal processing unit 44. In the embodiment, the signal processing unit 44 outputs data indicating changes (amplitudes) in the output of the detection signal Vdet of each photodiode PD (described later), and the output processing unit 50 determines which output is to be used as the sensor output Vo, but both of these functions may be performed by the signal processing unit 44 or the output processing unit 50.

[0038] Furthermore, since wearing a pulse wave or other detection device on the human body also detects noise associated with breathing, changes in posture, and human movement, the signal processing unit 44 may be provided with a noise filter as needed. The frequency components of noise caused by breathing and changes in posture are, for example, 1 Hz or less, which is sufficiently lower than the frequency components of the pulse wave. Therefore, they can be removed using a bandpass filter. The bandpass filter may be provided, for example, in the detection signal amplifier 42. The frequency components of noise caused by human movement, for example, are several Hz to 100 Hz, and may overlap with the frequency components of the pulse wave. However, in this case, the frequency is not constant but fluctuates, so a noise filter is used to remove frequencies with fluctuating components. As an example of a method for removing frequencies with fluctuating components (first fluctuation component removal method), one may utilize the property that pulse waves exhibit a time lag in their peak values ​​depending on the measurement location on the human body. In other words, pulse waves exhibit a time lag depending on the measurement location on the human body, while noise caused by human movement, for example, exhibits no time lag or a smaller time lag than pulse waves. Therefore, the pulse wave is measured at at least two different locations, and if the peak values ​​measured at the different locations are within a predetermined time, they are removed as noise. Even in this case, it is possible for the waveform due to noise and the waveform due to the pulse wave to overlap by chance. In this case, the two waveforms overlap only at one of the different locations, making it possible to distinguish between the waveform due to noise and the waveform due to the pulse wave. This process can be performed, for example, by the signal processing unit 44. As another example of a method for removing frequencies containing fluctuation components (a second fluctuation component removal method), the signal processing unit 44 removes frequency components with different phases. In this case, for example, a short-time Fourier transform may be performed to remove the fluctuation components, followed by an inverse Fourier transform. Furthermore, commercial frequency power sources (50 Hz, 60 Hz) are also a noise source. However, in this case, similar to noise caused by human movement, there is either no time lag between the peak values ​​measured at different locations or the time lag is smaller than that caused by the pulse wave. Therefore, noise removal can be achieved using a method similar to the first fluctuation component removal method described above.Alternatively, noise generated by the commercial frequency power supply may be removed by providing a shield on the surface of the detector opposite to the detection surface.

[0039] Next, an example of the circuit configuration of the sensor unit 10 will be described. Fig. 5 is a circuit diagram showing the sensor unit 10. Fig. 6 is a circuit diagram showing a plurality of partial detection areas. Note that Fig. 6 also shows the circuit configuration of the AFE 91.

[0040] 5, the sensor unit 10 has a plurality of partial detection areas PAA arranged in a matrix. Each of the partial detection areas PAA is provided with a photodiode PD.

[0041] The gate lines GCL extend in the first direction Dx and are connected to a plurality of partial detection areas PAA arranged in the first direction Dx. Furthermore, a plurality of gate lines GCL(1), GCL(2), ..., GCL(8) are arranged in the second direction Dy and are each connected to the gate line driving circuit 15. In the following description, when it is not necessary to distinguish between the plurality of gate lines GCL(1), GCL(2), ..., GCL(8), they will simply be referred to as gate lines GCL. Although FIG. 5 shows eight gate lines GCL for ease of explanation, this is merely an example, and M gate lines GCL (where M is 8 or more, e.g., M=256) may be arranged.

[0042] The signal line SGL extends in the second direction Dy and is connected to the photodiodes PD of the plurality of partial detection areas PAA arranged in the second direction Dy. The plurality of signal lines SGL(1), SGL(2), ..., SGL(12) are arranged in the first direction Dx and are each connected to the signal line selection circuit 16 and the reset circuit 17. In the following description, when it is not necessary to distinguish between the plurality of signal lines SGL(1), SGL(2), ..., SGL(12), they will be simply referred to as signal lines SGL.

[0043] For ease of understanding, 12 signal lines SGL are shown, but this is merely an example, and N signal lines SGL (N is 12 or more, for example, N=252) may be arranged. The resolution of the sensor is, for example, 508 dpi (dots per inch), and the number of cells is 252×256. In FIG. 5 , the sensor unit 10 is provided between the signal line selection circuit 16 and the reset circuit 17. However, this is not limiting, and the signal line selection circuit 16 and the reset circuit 17 may be connected to the ends of the signal lines SGL in the same direction. The effective area of ​​one sensor is, for example, substantially 50×50 μm ２ The area of ​​the detection area AA is, for example, 12.6×12.8 mm ２ It is said that.

[0044] The gate line driving circuit 15 receives various control signals, such as a start signal STV, a clock signal CK, and a reset signal RST1, from the control circuit 122 (see FIG. 3 ). Based on the various control signals, the gate line driving circuit 15 sequentially selects multiple gate lines GCL(1), GCL(2), ..., GCL(8) in a time-division manner. The gate line driving circuit 15 supplies a gate driving signal Vgcl to the selected gate line GCL. As a result, the gate driving signal Vgcl is supplied to multiple first switching elements Tr connected to the gate line GCL, and multiple partial detection areas PAA arranged in the first direction Dx are selected as detection targets.

[0045] The gate line driving circuit 15 may perform different driving for each detection mode of a fingerprint and a plurality of different pieces of biological information (pulse wave, pulse, blood vessel image, blood oxygen saturation, etc.) For example, the gate line driving circuit 15 may drive a bundle of a plurality of gate lines GCL.

[0046] Specifically, the gate line driving circuit 15 may simultaneously select a predetermined number of gate lines GCL from among the gate lines GCL(1), GCL(2), ..., GCL(8) based on a control signal. For example, the gate line driving circuit 15 simultaneously selects six gate lines GCL(1) to GCL(6) and supplies the gate driving signal Vgcl to the gate lines. The gate line driving circuit 15 supplies the gate driving signal Vgcl to a plurality of first switching elements Tr via the six selected gate lines GCL. As a result, group areas PAG1 and PAG2, each including a plurality of partial detection areas PAA arranged in the first direction Dx and the second direction Dy, are selected as detection targets. The gate line driving circuit 15 drives a predetermined number of gate lines GCL together and sequentially supplies the gate driving signal Vgcl to each of the predetermined number of gate lines GCL. Hereinafter, when the positions of different group areas, such as the group areas PAG1 and PAG2, are not particularly distinguished from one another, they will be referred to as group areas PAG.

[0047] The signal line selection circuit 16 has a plurality of selection signal lines Lsel, a plurality of output signal lines Lout, and a third switching element TrS. The plurality of third switching elements TrS are provided corresponding to the plurality of signal lines SGL, respectively. The six signal lines SGL(1), SGL(2), ..., SGL(6) are connected to a common output signal line Lout1. The six signal lines SGL(7), SGL(8), ..., SGL(12) are connected to a common output signal line Lout2. The output signal lines Lout1 and Lout2 are each connected to the AFE 91.

[0048] Here, the signal lines SGL(1), SGL(2), ..., SGL(6) are defined as a first signal line block, and the signal lines SGL(7), SGL(8), ..., SGL(12) are defined as a second signal line block. The multiple selection signal lines Lsel are connected to the gates of the third switching elements TrS included in one signal line block. Furthermore, one selection signal line Lsel is connected to the gates of the third switching elements TrS of multiple signal line blocks.

[0049] Specifically, the selection signal lines Lsel1, Lsel2, ..., Lsel6 are connected to the third switching elements TrS corresponding to the signal lines SGL(1), SGL(2), ..., SGL(6), respectively. The selection signal line Lsel1 is connected to the third switching element TrS corresponding to the signal line SGL(1) and the third switching element TrS corresponding to the signal line SGL(7). The selection signal line Lsel2 is connected to the third switching element TrS corresponding to the signal line SGL(2) and the third switching element TrS corresponding to the signal line SGL(8).

[0050] The control circuit 122 (see FIG. 3) sequentially supplies the selection signal ASW to the selection signal line Lsel. As a result, the signal line selection circuit 16 sequentially selects the signal lines SGL in one signal line block in a time-division manner through the operation of the third switching element TrS. The signal line selection circuit 16 also selects one signal line SGL from each of the multiple signal line blocks. This configuration allows the sensor module 1 to reduce the number of integrated circuits (ICs) including the AFE 91 or the number of IC terminals.

[0051] The signal line selection circuit 16 may bundle multiple signal lines SGL and connect them to the AFE 91. Specifically, the control circuit 122 (see FIG. 3) simultaneously supplies selection signals ASW to the selection signal lines Lsel. This causes the signal line selection circuit 16 to select multiple signal lines SGL (e.g., six signal lines SGL) in one signal line block through the operation of the third switching element TrS, and connect the multiple signal lines SGL to the AFE 91. This causes signals detected in each group area PAG to be output to the AFE 91. In this case, signals from multiple partial detection areas PAA (photodiodes PD) are integrated for each group area PAG and output to the AFE 91.

[0052] By performing detection for each group area PAG through the operation of the gate line driving circuit 15 and the signal line selection circuit 16, the strength of the detection signal Vdet obtained in one detection is improved, thereby improving sensor sensitivity. Furthermore, the time required for detection can be shortened. Therefore, the sensor module 1 can repeatedly perform detection in a short period of time, improving the S / N ratio and enabling accurate detection of temporal changes in information related to a living body, such as pulse waves.

[0053] 5, the reset circuit 17 has a reference signal line Lvr, a reset signal line Lrst, and fourth switching elements TrR. The fourth switching elements TrR are provided corresponding to the multiple signal lines SGL. The reference signal line Lvr is connected to one of the sources or drains of the multiple fourth switching elements TrR. The reset signal line Lrst is connected to the gates of the multiple fourth switching elements TrR.

[0054] The control circuit 122 supplies a reset signal RST2 to the reset signal line Lrst. This turns on the multiple fourth switching elements TrR, and electrically connects the multiple signal lines SGL to the reference signal line Lvr. The power supply circuit 123 supplies a reference signal COM to the reference signal line Lvr. This supplies the reference signal COM to the capacitive elements Ca (see FIG. 6) included in the multiple partial detection areas PAA.

[0055] As shown in FIG. 6 , the partial detection area PAA includes a photodiode PD, a capacitance element Ca, and a first switching element Tr. In FIG. 6 , two gate lines GCL(m) and GCL(m+1) arranged in the second direction Dy are shown among the multiple gate lines GCL. Also shown are two signal lines SGL(n) and SGL(n+1) arranged in the first direction Dx among the multiple signal lines SGL. The partial detection area PAA is an area surrounded by the gate lines GCL and the signal lines SGL. The first switching element Tr is provided corresponding to the photodiode PD. The first switching element Tr is formed of a thin-film transistor, and in this example, is formed of an n-channel MOS (Metal Oxide Semiconductor) TFT (Thin Film Transistor).

[0056] The gates of the first switching elements Tr belonging to the partial detection areas PAA aligned in the first direction Dx are connected to the gate line GCL, the sources of the first switching elements Tr belonging to the partial detection areas PAA aligned in the second direction Dy are connected to the signal line SGL, and the drains of the first switching elements Tr are connected to the cathodes of the photodiodes PD and the capacitance elements Ca.

[0057] A sensor power supply signal VDDSNS is supplied to the anode of the photodiode PD from the power supply circuit 123. Furthermore, a reference signal COM, which becomes the initial potential of the signal line SGL and the capacitance element Ca, is supplied from the power supply circuit 123 to the signal line SGL and the capacitance element Ca.

[0058] When light is irradiated onto the partial detection area PAA, a current corresponding to the amount of light flows through the photodiode PD, causing charge to accumulate in the capacitance element Ca. When the first switching element Tr is turned on, a current corresponding to the charge accumulated in the capacitance element Ca flows through the signal line SGL. The signal line SGL is connected to the AFE 91 via the third switching element TrS of the signal line selection circuit 16. This allows the sensor module 1 to detect a signal corresponding to the amount of light irradiated onto the photodiode PD for each partial detection area PAA or for each group area PAG.

[0059] During the readout period Pdet (see FIG. 7 ), the switch SSW of the AFE 91 is turned on, and the AFE 91 is connected to the signal line SGL. The detection signal amplifier 42 of the AFE 91 converts fluctuations in current supplied from the signal line SGL into fluctuations in voltage and amplifies the voltage. A reference potential (Vref) having a fixed potential is input to the non-inverting input terminal (+) of the detection signal amplifier 42, and the signal line SGL is connected to the inverting input terminal (−). In this embodiment, a signal identical to the reference signal COM is input as the reference potential (Vref) voltage. The detection signal amplifier 42 also has a capacitance element Cb and a reset switch RSW. During the reset period Prst (see FIG. 7 ), the reset switch RSW is turned on, and the charge of the capacitance element Cb is reset.

[0060] The AFE 91 shown in FIG. 1 functions at least as the A / D converter 43, converting an analog signal output from the sensor unit 10 into a digital signal and outputting it to the control unit 92. As in the embodiment, the AFE 91 may also function as the detection signal amplifier 42. The digital signal is a signal that can be interpreted by a calculation circuit included in the control unit 92, which is a circuit that functions as the signal processing unit 44. The AFE 91 also outputs a signal for controlling the lighting of the first light source 61 and the second light source 62 under the control of the control unit 92. The control unit 92 in the embodiment when the configurations described with reference to FIGS. 3 to 6 are applied includes the signal processing unit 44, the detection timing control unit 47, and the output processing unit 50.

[0061] The control unit 92 performs a plurality of processes related to detecting the vascular pattern of a human finger, such as determining that the finger Fi has been detected, acquiring the pattern of the blood vessels Ve, etc. The control unit 92 also determines the degree of pressure applied from the finger Fi to the sensor unit 10, and controls the notification unit 94 based on the determination.

[0062] Each of the AFE 91 and the control unit 92 has one or more circuits implemented to realize the above-mentioned functions. Such circuits may be circuits that integrate multiple functions, or may be circuits that are individually provided for each function.

[0063] The notification unit 94 has a light source that turns on or off in response to the result of the determination related to the degree of pressure applied from the finger Fi to the sensor unit 10. The light source is, for example, an LED or an OLED, but is not limited to this and may be any other specific configuration that functions in a similar manner. Details of the determination and the operation of the notification unit 94 will be described later.

[0064] The communication unit 95 performs processing related to communication with external devices. The communication unit 95 has a circuit for functioning as a NIC (Network Interface Controller) and performs processing related to communication with external devices in accordance with a predetermined protocol. The communication path used for such communication may be wired, wireless, or a mixed line path of wired and wireless, and may include a public communication network such as the Internet as part of the path.

[0065] In the embodiment, the control unit 92, the storage unit 93, and the communication unit 95 are integrated into the control circuit 122, but the specific implementation form is arbitrary. For example, some or all of the control unit 92, the storage unit 93, and the communication unit 95 may be provided as independent circuits.

[0066] Next, the degree of pressure applied from the finger Fi to the sensor unit 10 will be described with reference to FIG.

[0067] 7 is a schematic diagram showing the relationship between the degree of pressure applied by a finger Fi to the sensor unit 10 and the sensing result obtained by the sensor module 1. The sensing result here refers to the light and dark pattern of the detection area obtained by individually detecting light using multiple photodiodes PD arranged in the detection area. Furthermore, the blood vessels Ve are assumed to be veins, but may also be arteries.

[0068] The sensor module 1 of the embodiment can identify the blood vessels Ve in the finger Fi depending on the distance from the finger Fi, even when the object to be detected (finger Fi) is not in contact with the louver 99. Specifically, as shown in "Pattern 1" in Fig. 7, when the distance between the louver 99 and the finger Fi is distance D1, a sensing result Sd1 is obtained in which there is no shadow of light corresponding to the finger Fi, i.e., no dark area in the sensing result. Note that, as shown in "Pattern 1," the presence of the louver 99 does not substantially cause a shadow in the sensing result.

[0069] Hereinafter, when simply referred to as a dark area, it refers to a dark area in the sensing result that is caused by a shadow cast by the finger Fi blocking light emitted from the light source unit 5 toward the sensor unit 10. In other words, the white area surrounding the dark area in the sensing result is a bright area that is caused by the light emitted from the light source unit 5 toward the sensor unit 10 being detected almost as is. Therefore, it can be said that the sensing result indicates a light-dark pattern that is either a state of only bright areas, a state of only dark areas, or a state in which bright and dark areas are mixed.

[0070] In contrast to the above-described "Pattern 1," when the distance between the louver 99 and the finger Fi is a distance D2 that is shorter than the distance D1, as shown in "Pattern 2," a sensing result Sd2 is obtained in which a dark area corresponding to the finger Fi appears. Furthermore, when the distance between the louver 99 and the finger Fi is a distance D3 that is shorter than the distance D2, as shown in "Pattern 3," a sensing result Sd3 is obtained in which a dark area corresponding to the finger Fi and a pattern of blood vessels Ve within the dark area appear. The pattern of blood vessels Ve in the sensing result Sd3 can be confirmed, for example, within the area Fa1.

[0071] 7, the finger Fi comes into contact with the louver 99, resulting in a sensing result Sd4 in which the dark areas corresponding to the finger Fi are darker than in the sensing result Sd3. The pattern of the blood vessels Ve in the sensing result Sd4 can be confirmed, for example, within the area Fa2.

[0072] On the other hand, when the finger Fi comes into contact with the louver 99 and the pressure applied to the finger Fi toward the sensor unit 10 is too strong, a portion of the blood vessel Ve in the finger Fi may be crushed by such excessive pressure. The crushed blood vessel Ve is unlikely to appear as an image in the sensing result. For example, as shown in "Pattern 5" in FIG. 7, when the finger Fi is pressed strongly against the louver 99, a crushed blood vessel Ve occurs. Blood does not flow or flows poorly in the area where the crushed blood vessel Ve occurs. For this reason, the image of the blood vessel Ve is more difficult to distinguish in the area Fa3 of the sensing result Sd5 than in the areas Fa1 and Fa2.

[0073] 7 can also be considered as examples of a transition from a state in which the finger Fi is separated from the louver 99 to a state in which the finger Fi is pressed against the louver 99. When viewed in this manner, the sensing results transition as sensing results Sd1, Sd2, Sd3, Sd4, and Sd5, and the dark areas included in the sensing results gradually expand with the transition.

[0074] Note that the change in the range occupied by the dark part in the sensing result may be not only the enlargement described above but also a movement corresponding to a positional deviation of the finger Fi, etc. Whether the change in the range occupied by the dark part in the sensing result corresponds to a movement or an enlargement can be determined based on a comparison of the sensing results before and after the transition.

[0075] Fig. 8 is a schematic diagram showing a case where a change in the range occupied by a dark area in a sensing result corresponds to movement. In Fig. 8 and Fig. 9 described below, of two sensing results obtained at different times, a dark area included in the sensing result obtained by sensing performed relatively earlier is designated as dark area Si1. Also, in Fig. 8, a dark area included in the sensing result obtained by sensing performed relatively later is designated as dark area Si2.

[0076] The positions of the dark areas Si1 and Si2 in the first direction Dx are different in Fig. 8. Fig. 8 and Fig. 9 (described later) show graphs illustrating the difference between the presence and absence of dark areas in the first direction Dx in order to illustrate changes in the range occupied by dark areas in the sensing results. In the graphs, the horizontal axis represents the coordinate (x-coordinate) in the first direction Dx, and the vertical axis represents the output of the sensing results acquired by the AFE 91 from the sensor module 1. In the graphs, at the determination position Cs, if the dark areas increase in a relatively later sensing result, this is treated as a positive output, and if the dark areas decrease in a relatively later sensing result, this is treated as a negative output in the vertical direction.

[0077] Comparing the dark areas Si1 and Si2 shown in Figure 8, a negative output occurs in the range Db on one side of the x-coordinate, and a positive output occurs in the range Da on the other side of the x-coordinate. Here, ranges Db and Da are almost identical. Therefore, when looking at the overall output of the sensing result, the subtraction of the negative output from the positive output results in the size of the area occupied by the dark area being substantially the same in the relatively earlier sensing output including the dark area Si1 and the relatively later sensing output including the dark area Si2. In this way, if the size of the area occupied by the dark area does not change, the change in the dark area in the sensing result is considered to be due to the movement of the finger Fi.

[0078] Therefore, if the sensing result at one timing is considered to be the sensing result of "one frame," when a dark area that appears in the sensing result of a relatively later frame among two or more different timings is larger than a dark area that appears in the sensing result of a relatively earlier frame, it can be considered that the pressing force from the detected object (e.g., finger Fi) that causes the dark area toward the detection area of ​​the sensor unit 10 has increased during the multiple timings. In particular, when the pattern of blood vessels Ve is included in the dark area, the detected object can be considered to be a finger Fi.

[0079] 9 is a schematic diagram showing a case where the change in the range occupied by the dark area in the sensing result corresponds to enlargement. In FIG. 9, the dark area included in the sensing result by sensing performed at a relatively later timing is designated as dark area Si3.

[0080] 9 , a positive output is generated in the range Dc on one side of the x-coordinate and the range Dd on the other side of the x-coordinate. Therefore, when viewing the overall sensing result output, the range occupied by the dark area is larger in the relatively later sensing output including the dark area Si3 than in the relatively earlier sensing output including the dark area Si1. When the size of the range occupied by the dark area changes in this way, the change in the dark area in the sensing result is considered to be due to a change in the relative distance (closer distance) between the finger Fi and the sensor unit 10 or an increase in the pressing force from the finger Fi toward the sensor unit 10.

[0081] Conversely, if the dark area Si3 shown in FIG. 9 is a relatively earlier sensing result and the dark area Si1 is a relatively later sensing result, the change in the dark area in the sensing result, i.e., the reduction in the dark area, is considered to be due to a change in the relative distance between the finger Fi and the sensor unit 10 (increasing the distance) or a decrease in the pressing force from the finger Fi toward the sensor unit 10.

[0082] In the embodiment, it is possible to determine and notify that the pressure from the finger Fi to the sensor unit 10 is too strong based on the occurrence of a crushed pattern of the blood vessels Ve in a dark area included in the sensing result, such as the crushed pattern Cr described with reference to Fig. 7. When making such determination and notifying, it is also possible to further utilize the identification of an increase in the pressure described with reference to Figs.

[0083] 10 is a flowchart showing the processing flow of the detection device 100, including determining and reporting that the pressure from the finger Fi toward the sensor unit 10 is too strong. First, sensing is performed (step S1). Specifically, the photodiode PD of the sensor module 1 operates, and an output is generated according to the intensity of light emitted from the light source unit 5 and detected by the photodiode PD. This output is processed by the AFE 91 and the control unit 92, and becomes data that can be interpreted as a sensing result as described with reference to FIGS. 7 and 8.

[0084] The control unit 92 determines whether a finger has been detected by the sensing process in step S1 (step S2). Specifically, the control unit 92 performs a determination process to determine whether the sensing result obtained by the process in step S1 includes a dark area that can be determined to be caused by the finger Fi. This determination process includes multiple determinations, such as whether a dark area has occurred, whether, if a dark area has occurred, the proportion of the dark area relative to the entire sensing result is an appropriate proportion that can be interpreted as a dark area caused by the finger Fi, and if a dark area has occurred, whether the shape of the dark area can be interpreted as a dark area caused by the finger Fi. The specific content of the determination process can be changed as appropriate. Furthermore, with regard to the proportion of the dark area relative to the entire sensing result, a range that can be considered an appropriate proportion that can be interpreted as a dark area caused by the finger Fi is determined in advance based on a prior test or the like, and is held by the control unit 92. Furthermore, whether the shape of the dark area can be interpreted as a dark area caused by a finger Fi is determined based on, for example, pattern matching with sample data of dark areas caused by a finger Fi that has been prepared in advance. When such pattern matching is employed, the sample data is stored in the control unit 92 or a storage device that can be referenced by the control unit 92 and is provided in the detection device 100.

[0085] If it is determined in step S2 that a finger has not been detected (step S2; No), the process proceeds to step S1. That is, sensing is performed again. On the other hand, if it is determined in step S2 that a finger has been detected (step S2; Yes), the control unit 92 performs a process of acquiring a pattern of the blood vessels Ve from the sensing results obtained in step S1 (step S3). The process of acquiring the pattern of the blood vessels Ve is based on, for example, the contrast between the blood vessels Ve and areas other than the blood vessels Ve in the dark areas created by the finger Fi, and pattern matching with the shape of the area determined to be a possible blood vessel Ve based on the contrast, but the specific content of the process can be changed as appropriate. Furthermore, if such pattern matching is employed, the sample data is stored in the control unit 92 or a storage device accessible from the control unit 92 and provided in the detection device 100.

[0086] If a blood vessel Ve pattern is not obtained after the processing of step S3 (step S4; No), the process proceeds to step S1. On the other hand, if a blood vessel Ve pattern is obtained after the processing of step S3 (step S4; Yes), the control unit 92 determines whether sufficient data has been obtained for the purpose of the predetermined processing (step S5). For example, assume that the predetermined processing is a "personal authentication processing based on blood vessel patterns." In this case, it is sufficient that one or more blood vessel Ve patterns that can be compared with pre-prepared blood vessel patterns are obtained in the processing of step S3. Also assume that the predetermined processing is a "pulse measurement processing." In this case, it is sufficient that multiple sensing results are obtained in a predetermined cycle. This allows the pulse to be calculated from the relationship between the pulsations indicated by the multiple blood vessel Ve patterns and the time length of the predetermined cycle. Even in processing other than those exemplified here, the result of the processing of step S5 depends on the specific content of the predetermined processing.

[0087] If it is determined in step S5 that sufficient data according to the purpose has been obtained in the predetermined process (step S5; Yes), the process by the detection device 100 ends. On the other hand, if it is determined in step S5 that sufficient data according to the purpose has not been obtained in the predetermined process (step S5; No), difference extraction is performed in n-frame units (step S6). Specifically, after the start of the process, of the sensing results obtained in the process of step S1 that has already been performed up to the process of step S6, the most recent n sensing results (n is a natural number equal to or greater than 2) are extracted as targets for the process of step S7 described below. Note that if the number of times the process of step S1 has already been performed up to the process of step S6 is less than n, all sensing results are extracted as targets for the process of step S7.

[0088] The control unit 92 determines whether excessive pressure from the finger Fi toward the sensor unit 10 is deemed to exist (step S7). Specifically, the control unit 92 compares a sensing result obtained in a later sensing session among the sensing results extracted in the process of step S6 with an earlier sensing result. If, as a result of this comparison, the control unit 92 determines that the pattern of the blood vessels Ve is unclear or has disappeared in the later sensing session compared to the earlier sensing result, the control unit 92 determines that excessive pressure from the finger Fi toward the sensor unit 10 exists to the extent that the above-mentioned collapse Cr has occurred. In this determination process, the control unit 92 may determine that the disappearance of the pattern of the blood vessels Ve in the later sensing session is not due to movement of the finger Fi from the earlier sensing result, using the same concept as described with reference to FIG. 8. Conversely, if the finger Fi has moved, and the pattern of blood vessels Ve in the finger Fi that was generated in the previous sensing result is generated at a position corresponding to the finger Fi after the movement, it is deemed that there is no excessive pressure from the finger Fi toward the sensor unit 10.

[0089] If the processing of step S7 determines that there is excessive pressure from the finger Fi toward the sensor unit 10 (step S7; Yes), the detection device 100 performs a pressure response operation (step S8). Specifically, the control unit 92 turns on the notification unit 94. By turning on the notification unit 94, it is possible to notify a person who can see the notification unit 94, such as a user who is pressing the finger Fi toward the sensor unit 10, that excessive pressure from the finger Fi toward the sensor unit 10 is occurring. In other words, by turning on the notification unit 94, the notification unit 94 functions as a component for notifying that excessive pressure from the finger Fi toward the sensor unit 10 is occurring.

[0090] After the process of step S8 or when it is determined in the process of step S7 that there is no excessive pressure from the finger Fi toward the sensor unit 10 (step S7; No), the process proceeds to step S1.

[0091] Note that step S2 can be omitted. That is, after the processing of step S1, the process may automatically proceed to the processing of step S3. In this case, the control unit 92 may consider that the finger Fi has been detected when the pattern of the blood vessel Ve is obtained in the processing of step S4 (step S4; Yes). That is, the processing of step S4 may also serve as the processing of step S2.

[0092] The lighting of the notification unit 94 is not limited to the processing of step S8. For example, the notification unit 94 may be configured to light up in a first pattern when a blood vessel Ve pattern is obtained in the processing of step S4 (step S4; Yes), and to light up in a second pattern when the processing of step S8 is performed. In this case, the first pattern indicates that a blood vessel Ve pattern has been obtained normally. The second pattern indicates that the pressure from the finger Fi toward the sensor unit 10 is too strong. The first and second patterns are different lighting patterns, but the manner in which they are differentiated may be arbitrary. For example, the color of the light source lit in the first pattern may be different from the color of the light source lit in the second pattern. Furthermore, as a lighting pattern for a certain light source, the lighting state in the first pattern may be different from the lighting state in the second pattern. For example, the light source may be continuously lit in the first pattern, and the light source may repeatedly flash in the second pattern.

[0093] As described above, according to the embodiment, the detection device (detection device 100) includes a sensor unit (sensor unit 10) having a plurality of optical sensors (photodiodes PD) arranged two-dimensionally, and an acquisition unit (control unit 92) that acquires a pattern of blood vessels (blood vessels Ve) in a human finger (finger Fi) contained in the light and dark pattern of light detected by the sensor unit, and the acquisition unit acquires information about the pressure from the finger toward the sensor unit based on the light and dark pattern. Therefore, according to the embodiment, the pressure can be detected based on the light and dark pattern without providing a dedicated pressure sensor for detecting the pressure.

[0094] 7 and 8, if the dark areas in a relatively later light-dark pattern among multiple light-dark patterns obtained at different timings are larger than the dark areas in a relatively earlier light-dark pattern, the acquisition unit (control unit 92) determines that the pressure from the finger (finger Fi) has increased during acquisition of the multiple light-dark patterns. This makes it possible to detect whether the pressure has increased based on whether the size of the dark areas included in the light-dark patterns has increased.

[0095] 7, if a blood vessel pattern included in a relatively earlier light and dark pattern among multiple light and dark patterns obtained at different times becomes unclear or disappears in a relatively later light and dark pattern, the obtaining unit (control unit 92) determines that the pressure from the finger (finger Fi) was too strong when the relatively later light and dark pattern was obtained. This makes it possible to detect that the pressure was too strong based on the blood vessel pattern included in the light and dark patterns.

[0096] The detection device (detection device 100) also includes a notification unit (notification unit 94) that notifies the user of the pressing force from the finger (finger Fi) to the sensor unit (sensor unit 10). This allows the notification unit to notify the user who is pressing the finger (finger Fi) against the sensor unit, or any other person who can receive notification from the notification unit, of information related to the pressing force.

[0097] The light source (second light source 62) is provided at a position opposite to the surface on which the plurality of optical sensors (photodiodes PD) are arranged, and emits light including at least one of visible light and infrared light, thereby more reliably generating dark areas on the surface caused by the finger (finger Fi).

[0098] (Modification) Modifications of the embodiment will be described below with reference to Fig. 11 and Fig. 12. In the description of the modification, configurations that are the same as those in the embodiment will not be particularly mentioned, and the same reference numerals will be used and description thereof will be omitted.

[0099] 11 is a block diagram showing an example of the main configuration of a detection device 100A according to a modification. The detection device 100A further includes an operation unit 96 in addition to the components included in the detection device 100.

[0100] 12 is a schematic diagram showing the positional relationship between the sensor module 1, light source unit 5, operating unit 96, and their peripheral configuration in the detection device 100A, and the blood vessel Ve of the finger Fi, which is the target of detection by the sensor module 1. The operating unit 96 is provided so as to be switchable between a state in which it protrudes toward the finger Fi and a state in which it does not protrude toward the finger Fi, based on the closest position of the finger Fi to the sensor unit 10. Here, the "closest position of the finger Fi to the sensor unit 10" is, for example, position BL on the surface of the louver 99 facing the finger Fi. In other words, when the finger Fi abuts on the surface of the louver 99 facing the finger Fi, the finger Fi is considered to be closest to the sensor unit 10. Note that if the louver 99 is omitted, the "closest position of the finger Fi to the sensor unit 10" is the surface of the sensor unit 10 on which multiple photodiodes PD are provided, i.e., the surface of the detection area.

[0101] When the pressing force of the finger Fi is too high, the operating unit 96 drives the operating unit to push up the finger Fi. When the pressing force of the finger Fi is too high, it is, for example, a case like pattern 5 described with reference to FIG. 7 , and in such a case, the pressing force of the finger Fi is deemed to be too high (above a predetermined value). For example, the operating unit 96 includes a rotationally driven electric motor and an eccentric cam fixed to the output shaft of the electric motor and configured so that the outer diameter relative to the center of rotation of the output shaft varies depending on the rotation angle. In the operating unit 96 of this example, which portion of the eccentric cam is on the side of the "closest position of the finger Fi to the sensor unit 10" changes depending on the rotation angle of the rotation shaft. The operating unit 96 is configured so that both a rotation angle of the rotation shaft at which a portion of the outer circumferential surface of the eccentric cam protrudes toward the finger Fi beyond the "closest position of the finger Fi to the sensor unit 10" and a rotation angle of the rotation shaft at which the eccentric cam does not protrude toward the finger Fi beyond the "closest position of the finger Fi to the sensor unit 10" occur. It should be noted that this example is merely one example of a specific configuration of the operating unit 96 and is not limited to this. For example, the operating unit 96 may be an operating mechanism that is provided so as to be able to switch between protruding and not protruding toward the finger Fi from the "closest position of the finger Fi to the sensor unit 10" by linear movement of an actuator. The operating unit 96 only needs to be provided so as to be able to switch between protruding and not protruding toward the finger Fi based on the "closest position of the finger Fi to the sensor unit 10", and its specific configuration is not limited thereto.

[0102] The operating unit 96 operates to protrude toward the finger Fi from the "closest position of the finger Fi to the sensor unit 10" when the pressing force from the finger Fi is deemed to be too strong. In a modified example, during the processing of step S8 described with reference to FIG. 10 , the control unit 92 operates the operating unit 96 to protrude toward the finger Fi from the "closest position of the finger Fi to the sensor unit 10." This causes the finger Fi to receive a biasing force from the operating unit 96 in a direction away from the "closest position of the finger Fi to the sensor unit 10." The operation of the operating unit 96 is intended to suggest to the user of the finger Fi, via the tactile sensation with the operating unit 96, that the pressing force toward the "closest position of the finger Fi to the sensor unit 10" be eased. By receiving a feeling from the operating unit 96 that the finger Fi is being pushed up from the "closest position of the finger Fi to the sensor unit 10," the user of the finger Fi can easily realize that the pressing force applied from the finger Fi toward the sensor unit 10 is too strong.

[0103] Furthermore, in a modified example, if it is determined in the process of step S7 performed after the process of step S8 has been performed one or more times that there is no excessive pressure from the finger Fi toward the sensor unit 10 (step S7; No), the control unit 92 operates the operating unit 96 so that it does not protrude toward the finger Fi from the "closest position of the finger Fi to the sensor unit 10." This makes it easier for the user of the finger Fi to realize that the state in which the pressure from the finger Fi toward the sensor unit 10 is too strong has been resolved.

[0104] In addition, in the modified example, the control is not limited to the operation control of the operation unit 96, and the lighting control of the notification unit 94 may be further performed as in the embodiment. As described above, except for the points specifically mentioned, the modified example is the same as the embodiment.

[0105] As described above, according to the modified example, an operating unit (operating unit 96) is provided adjacent to the sensor unit (sensor unit 10) and is switchable between a state in which it protrudes toward the finger (finger Fi) and a state in which it does not protrude toward the finger in response to the pressure from the finger toward the sensor unit, based on the closest position (position BL) of the finger (finger Fi) to the sensor unit. This allows output according to the pressure via the operating unit.

[0106] Furthermore, the operating unit (operating unit 96) protrudes toward the finger (finger Fi) when the pressure from the finger (finger Fi) is deemed to be too strong, thereby indicating to the user pressing the finger (finger Fi) against the sensor unit (sensor unit 10) that the pressure is too strong through the tactile sensation generated by the operating unit on the finger.

[0107] The configuration functioning as the notification unit is not limited to the notification unit 94 or the operation unit 96, and the specific configuration can be changed as appropriate. For example, a voice output device including a speaker that notifies the user by voice that the pressing force is too strong, an amplifier, and a storage device that stores voice data may be employed as the notification unit. Also, a display device that outputs an image such as an image containing text information to notify the user, a display driver circuit, and a storage device that stores image data output by the display may be employed as the notification unit.

[0108] Furthermore, other effects and advantages brought about by the aspects described in this embodiment that are clear from the description in this specification or that can be appropriately thought of by a person skilled in the art are naturally understood to be brought about by the present disclosure.

[0109] REFERENCE SIGNS LIST 1 sensor module 5 light source unit 10 sensor unit 62 second light source 92 control unit 94 notification unit 96 operation unit 100, 100A detection device Fi finger Ve blood vessel

Claims

1. A detection device comprising: a sensor unit having a plurality of optical sensors arranged two-dimensionally; and an acquisition unit that acquires a pattern of blood vessels in a human finger contained in a light and dark pattern detected by the sensor unit, wherein the acquisition unit acquires information regarding the pressure applied from the finger to the sensor unit based on the light and dark pattern.

2. The detection device according to claim 1, wherein the acquisition unit determines that the pressure from the finger has increased during acquisition of multiple light and dark patterns when the dark areas in a relatively later light and dark pattern among multiple light and dark patterns obtained at different times are larger than the dark areas in a relatively earlier light and dark pattern.

3. The detection device according to claim 1 or 2, wherein the acquisition unit determines that the pressure from the finger was too strong when the relatively later light and dark pattern was acquired if a blood vessel pattern contained in a relatively earlier light and dark pattern among multiple light and dark patterns acquired at different times becomes unclear or disappears in the relatively later light and dark pattern.

4. The detection device according to claim 1 or 2, further comprising an alarm unit that provides an alarm regarding a pressure applied from the finger to the sensor unit.

5. A detection device as claimed in claim 1 or 2, further comprising a light source that is provided at a position opposite to the surface on which the plurality of optical sensors are arranged and that emits light including at least one of visible light and infrared light.

6. A detection device as described in claim 3, further comprising an operating unit provided adjacent to the sensor unit and capable of switching between a state in which it protrudes toward the finger and a state in which it does not protrude toward the finger in response to a pressure applied from the finger toward the sensor unit, based on the closest position of the finger to the sensor unit.

7. The detection device according to claim 6, wherein the operating portion protrudes toward the finger when the pressure from the finger is deemed to be too strong.

Images