Element array circuits, electromagnetic wave sensors, temperature sensors, and strain sensors

Abstract

To provide an element array circuit that can obtain a measured value related to a resistance value or the like quickly with high accuracy.SOLUTION: An element array circuit includes one or more first wiring lines, a plurality of second wiring lines, a plurality of impedance elements, one or more operational amplifiers, one or more conversion elements, and one or more switching portions. The plurality of second wiring lines each extends in a direction different from a direction in which one or more first wiring lines extend. The plurality of impedance elements is each coupled to both one of one or more first wiring lines and one of the plurality of second wiring lines. One or more operational amplifiers each include a positive input terminal, a negative input terminal that can be coupled to one of the plurality of second wiring lines, and an output terminal. One or more conversion elements are each coupled to the negative input terminal and the output terminal, and each convert a current flowing through one of the plurality of second wiring lines coupled to the negative input terminal into voltage. One or more switching portions are each coupled to one of the one or more conversion elements in parallel between the negative input terminal and the output terminal, and may come into either a conduction state or a non-conduction state.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an element array circuit having an element array in which a plurality of impedance elements are arranged, and an electromagnetic wave sensor, a temperature sensor, and a strain sensor including the same.

Background Art

[0002] Conventionally, a resistance element array circuit having a plurality of resistance elements arranged in a matrix has been disclosed. Such a resistance element array circuit is used, for example, as an infrared detection circuit (see, for example, Patent Document 1). In such an infrared detection circuit, a plurality of infrared-sensitive resistors such as thermistors whose resistance values change according to temperature changes are arranged.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in an element array circuit such as such an infrared detection circuit, it is desired to obtain a measurement value related to a resistance value or the like quickly and with high accuracy.

Means for Solving the Problems

[0005] The element array circuit according to an embodiment of the present invention includes one or more first wirings, a plurality of second wirings, a plurality of impedance elements, one or more operational amplifiers, one or more conversion elements, and one or more switching units. The plurality of second wirings are connected to one or more first wirings Each ofEach extends in a different direction. Multiple impedance elements are each connected to both one or more first wires and one of multiple second wires. Each of the one or more operational amplifiers has a positive input terminal, a negative input terminal connectable to one of the multiple second wires, and an output terminal. Each of the one or more conversion elements is Of the one or more operational amplifiers, one corresponding operational amplifier It is connected to the negative input terminal and output terminal, and converts the current flowing through one of several second wires connected to the negative input terminal into a voltage. Each of the one or more switching units is, Of the one or more operational amplifiers, one corresponding operational amplifier It is connected in parallel with one or more conversion elements between the negative input terminal and the output terminal, and can take on both conductive and non-conductive states.

[0006] In an element array circuit according to one embodiment of the present invention, by setting the switching unit to a conductive state and connecting the second wiring connected to the negative input terminal to the output terminal, the parasitic capacitance parasitic to the second wiring connected to the negative input terminal is quickly charged. After this charging, the switching unit is switched to a non-conductive state, and the output voltage from the output terminal caused by the impedance element can be measured. [Effects of the Invention]

[0007] According to one embodiment of the present invention, an element array circuit can be used to obtain measurement values ​​quickly and with high accuracy. [Brief explanation of the drawing]

[0008] [Figure 1] This is a circuit diagram showing an example configuration of an element array circuit according to the first embodiment of the present invention. [Figure 2] This is a flowchart illustrating an example of the measurement operation of the element array circuit shown in Figure 1. [Figure 3] Figure 1 is a circuit diagram illustrating the charging operation of parasitic capacitance in the element array circuit shown. [Figure 4] This is an explanatory diagram for illustrating the change in output voltage in the element array circuit shown in Figure 1. [Figure 5] This is a circuit diagram showing an example configuration of an element array circuit according to a second embodiment of the present invention. [Figure 6] This is a circuit diagram showing an example configuration of an element array circuit according to a third embodiment of the present invention. [Figure 7] This is a flowchart illustrating an example of the measurement operation of the element array circuit shown in Figure 6. [Figure 8] Figure 6 is a circuit diagram illustrating the charging operation of parasitic capacitance in the element array circuit shown. [Figure 9] This is a circuit diagram showing an example configuration of an element array circuit according to a fourth embodiment of the present invention. [Figure 10] This is a schematic diagram showing an example configuration of a sensor device according to a fifth embodiment of the present invention. [Figure 11] This is a circuit diagram showing an example configuration of an element array circuit as a first modification of the present invention. [Figure 12] This is a circuit diagram showing an example configuration of an element array circuit as a second modification of the present invention. [Figure 13] This is a circuit diagram showing an example configuration of an element array circuit as a third modified example of the present invention. [Figure 14] This is a circuit diagram showing an example configuration of an element array circuit as a fourth modified example of the present invention. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described in detail below with reference to the drawings. The description will be in the following order. 1. First Embodiment (First example of an element array circuit comprising multiple column wires and multiple operational amplifiers) 2. Second Embodiment (Second Example of an Element Array Circuit comprising Multiple Column Wires and Multiple Operational Amplifiers) 3. Third Embodiment (First Example of an Element Array Circuit Equipped with a Column Line Selection Unit) 4. Fourth Embodiment (Second Example of an Element Array Circuit Equipped with a Column Line Selection Unit) 5. Fifth Embodiment (Example of a Sensor Device Equipped with an Element Array Circuit) 6. Variations

[0010] <1. First Embodiment> [Overall Configuration Example of Element Array Circuit 1] FIG. 1 is a circuit diagram schematically showing a configuration example of an element array circuit 1 according to a first embodiment of the present invention. The element array circuit 1 is mounted on, for example, an infrared thermography, and is configured to output an output voltage according to the intensity of infrared rays irradiated to the element array circuit 1.

[0011] As shown in FIG. 1, the element array circuit 1 includes, for example, a plurality of row lines A (denoted as A1 to Am in FIG. 1), a plurality of column lines B (denoted as B1 to Bn in FIG. 1), a plurality of resistance elements R (denoted as R(1,1) to R(m,n) in FIG. 1), a row line selection unit SA, a plurality of operational amplifiers OP (denoted as OP1 to OPn in FIG. 1), a plurality of capacitor elements CP (denoted as CP1 to CPn in FIG. 1), and a plurality of switches SW (denoted as SW1 to SWn in FIG. 1), and a control unit CTRL. In FIG. 1, a state where m row lines A are arranged is illustrated, but the number of the plurality of row lines A can be arbitrarily set. Similarly, in FIG. 1, a state where n column lines B are arranged is illustrated, but the number of the plurality of column lines B can be arbitrarily set. Also, in FIG. 1 , the resistance element R connected to both the a-th row line Aa among the m row lines A1 to Am and the b-th column line Bb among the n column lines B1 to Bn is denoted as R(a,b). The same notation is used in the drawings after FIG. 1. Also, the plurality of row lines A and the plurality of column lines B are not in direct contact with each other.

[0012] (Row Line A)<00001​​​​​​The first end of each of the multiple wax wires A can be connected to a DC power supply PS1 via switch SWA1 (denoted as SWA1-1 to SWA1-m in Figure 1) of the wax wire selection unit SA, and can also be connected to a DC power supply PS2 via switch SWA2 (denoted as SWA2-1 to SWA2-m in Figure 1) of the wax wire selection unit SA. In addition, the first ends of multiple resistor elements R are connected to each of the multiple wax wires A. In the example in Figure 1, n resistor elements R are connected in parallel to one wax wire A. Specifically, the first ends of resistor elements R(1,1) to R(1,n), which are arranged in the Y-axis direction, are connected to wax wire A1 that extends in the Y-axis direction. Similarly, the first ends of the resistive elements R(2,1) to R(2,n), which are aligned in the Y-axis direction, are connected to the wax wire A2 extending in the Y-axis direction, and the first ends of the resistive elements R(m,1) to R(m,n), which are aligned in the Y-axis direction, are connected to the wax wire Am extending in the Y-axis direction. In the example in Figure 1, the second end opposite to the first end of each of the multiple wax wires A is connected to the first ends of the resistive elements R(1,n) to R(m,n), which are aligned in the X-axis direction.

[0014] When measuring a resistor R selected from multiple resistors R (referred to as the selected resistor RS for convenience), a switch SWA1 corresponding to the selected resistor AS (referred to as the selected resistor AS for convenience) is set to a conductive state so that a first voltage V1 is applied from the DC power supply PS1 to the selected resistor AS. Furthermore, when measuring the selected resistor RS, a second voltage V2 (≠V1) is applied from the DC power supply PS2 to all resistors A other than the selected resistor AS (referred to as the non-selected resistors AU for convenience) via a switch SWA2 that is set to a conductive state and corresponds to the non-selected resistors AU. Figure 1 shows, as an example, a state in which the resistive elements R(1,1) to R(1,n) are selected. Specifically, Figure 1 shows a state in which the switch SWA1-1 is in a conductive state, thereby applying a first voltage V1 from the DC power supply PS1 to the selective solder wire A1 corresponding to the selective resistive elements R(1,1) to R(1,n), and a state in which the switches SWA2-2 to SWA2-m are in a conductive state, thereby applying a second voltage V2 (≠V1) from the DC power supply PS2 to all non-selective solder wires A2 to Am other than the selective solder wire A1. In this case, the switches SWA1-2 to SWA1-m connected to the non-selective solder wires A2 to Am are all in a non-conductive state, and the switch SWA2-1 connected to the selective solder wire A1 is also in a non-conductive state. Either the first voltage V1 or the second voltage V2 may be 0V.

[0015] (Column line B) Column wire B is a specific example corresponding to the "second wiring" of the present invention. Each of the multiple column lines B extends in a different direction from the multiple wax lines A. For example, each of the multiple column lines B extends in a second direction, and the multiple column lines B are aligned adjacent to each other in a first direction different from the second direction. In the example in Figure 1, the multiple column lines B each extend in the X-axis direction, for example, and are aligned adjacent to each other in the Y-axis direction.

[0016] The first end of each of the multiple column wires B is connected to the corresponding operational amplifier OP among the multiple operational amplifiers OP. Specifically, the first end of column wire B1 is connected to the negative input terminal T2 of operational amplifier OP1, the first end of column wire B2 is connected to the negative input terminal T2 of operational amplifier OP2, and the first end of column wire Bn is connected to the negative input terminal T2 of operational amplifier OPn.

[0017] Furthermore, the second ends of multiple resistive elements R are connected to each of the multiple column wires B. The second end of a resistive element R is the end opposite to the first end connected to the wax wire A. In the example in Figure 1, m resistive elements R are connected in parallel to one column wire B. Specifically, the second ends of the resistive elements R(1,1) to R(m,1) arranged in the X-axis direction are connected to the column wire B1 extending in the X-axis direction. Similarly, the second ends of the resistive elements R(1,2) to R(m,2) arranged in the X-axis direction are connected to the column wire B2 extending in the X-axis direction, and the second ends of the resistive elements R(1,n) to R(m,n) arranged in the X-axis direction are connected to the column wire Bn extending in the X-axis direction. In the example in Figure 1, the second end of each of the multiple column wires B, opposite to the first end, is connected to the second ends of the resistive elements R(m,1) to R(m,n) arranged in the Y-axis direction.

[0018] (Resistor R) The resistive element R is a specific example corresponding to the "impedance element" of the present invention. Each of the multiple resistive elements R is connected to both one of the multiple wax wires A and one of the multiple column wires B. Each of the multiple resistive elements R has a first end connected to wax wire A and a second end connected to column wire B. As mentioned earlier, in the example in Figure 1, n resistive elements R are connected to each of the multiple wax wires A, and m resistive elements R are connected to each of the multiple column wires B. There is one resistive element R that is connected to both one wax wire A from the multiple wax wires A and one column wire B from the multiple column wires B. Therefore, one resistive element R can be identified by selecting one wax wire A from the multiple wax wires A and one column wire B from the multiple column wires B.

[0019] The resistive element R is part of an infrared light receiving element that converts infrared light focused by, for example, a lens, into an electrical signal. Specifically, it is a resistive layer that exhibits a change in resistance due to temperature changes. The resistive layer is, for example, a thermistor film. The thermistor film contains, for example, vanadium oxide, amorphous silicon, polycrystalline silicon, a spinel-type crystalline oxide containing manganese, titanium oxide, or yttrium-barium-copper oxide. An infrared absorbing layer that absorbs infrared light and generates heat is provided adjacent to the thermistor film. The infrared absorbing layer contains, for example, silicon oxide (SiO2), aluminum oxide (Al2O3), silicon nitride (Si3N4), or aluminum nitride (AlN). The resistive element R undergoes temperature changes in the infrared absorbing layer and the resistive layer depending on the intensity of the infrared light it receives, resulting in a change in the resistance value of the resistive layer.

[0020] (Waxed wire selection section SA) The wax wire selection unit SA has a plurality of switches SWA1 (SWA1-1 to SWA1-m) and a plurality of switches SWA2 (SWA2-1 to SWA2-m). Each of the plurality of switches SWA1 (SWA1-1 to SWA1-m) and the plurality of switches SWA2 (SWA2-1 to SWA2-m) is capable of switching between a conductive state and a non-conductive state. Each of the plurality of switches SWA1 (SWA1-1 to SWA1-m) is provided between a corresponding wax wire A (A1 to Am) and the DC power supply PS1. Each of the plurality of switches SWA2 (SWA2-1 to SWA2-m) is provided between a corresponding wax wire A (A1 to Am) and the DC power supply PS2.

[0021] The wax wire selection unit SA selects one of several wax wires A (referred to as the selected wax wire AS for convenience), connects that selected wax wire AS to the DC power supply PS1 that applies the first voltage V1 to the selected wax wire AS, and deselects the other wax wires A that are not selected AS. Waxed wireThe unselected wiring AU is connected to a DC power supply PS2 that applies a second voltage V2 to AU. The second voltage V2 is different from the first voltage V1. The operation of the wax wire selection unit SA is controlled by the control unit CTRL. That is, the switching operations of the multiple switches SWA1 (SWA1-1 to SWA1-m) and multiple switches SWA2 (SWA2-1 to SWA2-m) in the wax wire selection unit SA are performed based on commands from the control unit CTRL.

[0022] (Operational amplifier OP) Each of the multiple operational amplifiers (OP) is connected to a corresponding column line B of the multiple column lines B. Each of the multiple operational amplifiers (indicated as OP1 to OPn in Figure 1) includes a positive input terminal T1, a negative input terminal T2, and an output terminal T3. The positive input terminal T1 is connected to a DC power supply PS2, and a second voltage V2 is applied to the positive input terminal T1. The negative input terminal T2 is connected to a corresponding column line B. Each operational amplifier (OP) operates so that the positive input terminal T1 and the negative input terminal T2 are at the same potential, so the potential of the negative input terminal T2 is approximately the second voltage V2. The output terminal T3 is connected to the negative input terminal T2 via a capacitive element CP.

[0023] (Capacitive element CP) Capacitive element CP is one specific example corresponding to the "conversion element" of the present invention. Each of the multiple capacitive elements CP is connected to both the negative input terminal T2 and the output terminal T3 of a corresponding operational amplifier OP, and converts the current flowing through column line B, which is connected to the negative input terminal T2, into a voltage. Specifically, in the example in Figure 1, capacitive element CP1 is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OP1, and converts the current flowing through column line B1 into a voltage. Similarly, capacitive element CP2 is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OP2, and converts the current flowing through column line B2 into a voltage, and capacitive element CPn is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OPn, and converts the current flowing through column line Bn into a voltage.

[0024] (Switch SW) Switch SW is one specific example corresponding to the "switching unit" of the present invention. Each of the multiple switches SW is connected to a corresponding operational amplifier OP from among multiple operational amplifiers OP. Each of the multiple switches SW is connected in parallel to a corresponding capacitive element CP between the negative input terminal T2 and output terminal T3 of the corresponding operational amplifier OP. Each of the multiple switches SW can be in a conduction state or a non-conduction state. Specifically, in the example in Figure 1, switch SW1 is connected in parallel to the capacitive element CP1 between the negative input terminal T2 and output terminal T3 of operational amplifier OP1 and can be in a conduction state or a non-conduction state. Similarly, switch SW2 is connected in parallel to the capacitive element CP2 between the negative input terminal T2 and output terminal T3 of operational amplifier OP2 and can be in a conduction state or a non-conduction state. Switch SWn is connected in parallel to the capacitive element CPn between the negative input terminal T2 and output terminal T3 of operational amplifier OPn and can be in a conduction state or a non-conduction state.

[0025] (Control Unit CTRL) The control unit CTRL is, for example, a microcomputer, and the CPU (Central Processing Unit) executes a control program to perform predetermined control processing. The control unit CTRL controls the switching operation of multiple switches SW. The control unit CTRL charges the parasitic capacitance of each of the multiple column wires B, and then controls the switching of one switch SW corresponding to each column wire B to a non-conducting state. The control unit CTRL charges the parasitic capacitance of each column wire B by making one switch SW corresponding to each column wire B conduct, and making the column wire B connected to the negative input terminal T2 of the corresponding operational amplifier OP conduct to the output terminal T3 of the corresponding operational amplifier OP.

[0026] Furthermore, the control unit CTRL controls the switching operation of the wax wire selection unit SA. Specifically, the control unit CTRL sets one switch SWA1 corresponding to the selected wax wire AS to a conductive state, and the other switches SWA1 corresponding to the non-selected wax wire AU to a non-conductive state. In addition, the control unit CTRL sets one switch SWA2 corresponding to the selected wax wire AS to a non-conductive state, and the other switches SWA2 corresponding to the non-selected wax wire AU to a conductive state. Here, the selected wax wire AS is one wax wire A corresponding to the selection resistor RS. The non-selected wax wire AU is all other wax wires A other than the selected wax wire AS.

[0027] The control unit CTRL charges the parasitic capacitance of each column wire B, then switches a switch SW corresponding to each column wire B to a non-conductive state, and then measures the output voltage from the output terminal T3 of the operational amplifier OP corresponding to each column wire B, which is caused by the selective resistor RS connected to both the selective wax wire AS and each column wire B.

[0028] Furthermore, the time required to charge the parasitic capacitance of each column wire B by keeping the switch SW corresponding to each column wire B in a conductive state should be longer than the time required for almost all of the charge of the capacitive element CP corresponding to each column wire B to be discharged. Specifically, that time should be equal to the capacitance value of the capacitive element CP corresponding to each column wire B and In that capacitive element CP The time required to charge the parasitic capacitance of each column wire B by conducting the corresponding switch SW should be longer than five times the product of the capacitance value of the parasitic capacitance of each column wire B and the resistance value of the corresponding switch SW. This is because the parasitic capacitance of each column wire B is sufficiently charged, allowing for accurate measurement of the output voltage caused by each of the selective resistor elements RS.

[0029] Each of the DC power supplies PS1 and PS2 may be located inside the element array circuit 1 or outside the element array circuit 1.

[0030] [Measurement operation in element array circuit 1] In the element array circuit 1, measurements can be performed for each of the multiple resistor elements R, for example, as shown below. Note that the following measurement operations are performed by commands from the control unit CTRL.

[0031] Figure 2 is a flowchart illustrating an example of the measurement operation of the element array circuit 1. First, all switches are set to a non-conductive state (step S101). Specifically, all of the switches SW1 (SW1~SWn), SWA1 (SWA1-1~SWA1-m), and SWA2 (SWA2-1~SWA2-m) shown in Figure 1 are set to a non-conductive state (open state).

[0032] Next, select the selection wax wire AS corresponding to the selection resistor element RS to be measured (step S102). Specifically, the selection wax wire AS to which the selection resistor element RS is connected. Corresponding Switch SWA1 is set to conduct, and the first voltage V1 is applied to the selected wax wire AS. Switch SWA1 corresponding to the non-selected wax wire AU remains in a non-conductive state. Furthermore, the non-selected wax wire AU CorrespondingSwitch SWA2 is set to conduct, and a second voltage V2 is applied to the non-selective wax wire AU. Switch SWA2 corresponding to the selective wax wire AS remains in a non-conductive state. The example in Figure 1 shows a state in which the resistive elements R(1,1) to R(1,n) are selected as the selective resistive element RS. That is, switch SWA1-1 corresponding to wax wire A1 as the selective wax wire AS is set to conduct, and a first voltage V1 is applied to wax wire A1. On the other hand, switches SWA1-2 to SWA1-m corresponding to wax wires A2 to Am as the non-selective wax wire AU remain in a non-conductive state. Furthermore, switches SWA2-2 to SWA2-m corresponding to wax wires A2 to Am as the non-selective wax wire AU are set to conduct, and a second voltage V2 is applied to wax wires A2 to Am. On the other hand, switch SWA2-1 corresponding to wax wire A1 as the selective wax wire AS remains in a non-conductive state.

[0033] Next, one switch SW corresponding to each column wire B is turned on (step S103), and the parasitic capacitance of each column wire B is charged. ru.Specifically, one switch SW corresponding to each column line B is set to a conductive state, thereby connecting the column line B connected to the negative input terminal T2 of the corresponding operational amplifier OP with the output terminal T3 of the corresponding operational amplifier OP. In the example in Figure 1, switch SW1 corresponding to column line B1 to which the resistor element R(1,1) as a selective resistor element RS is connected is set to a conductive state, thereby connecting the negative input terminal T2 and output terminal T3 of operational amplifier OP1. Similarly, switch SW2 corresponding to column line B2 to which the resistor element R(1,2) as a selective resistor element RS is connected is set to a conductive state, thereby connecting the negative input terminal T2 and output terminal T3 of operational amplifier OP2. Switch SWn corresponding to column line Bn to which the resistor element R(1,n) as a selective resistor element RS is connected is set to a conductive state, thereby connecting the negative input terminal T2 and output terminal T3 of operational amplifier OPn. Figure 3 shows a circuit diagram illustrating the charging operation of the parasitic capacitance PC in the element array circuit 1. As shown by the dashed arrows in Figure 3, by turning switch SW1 into a conductive state, current flows from the operational amplifier OP1 to column wire B1, and the parasitic capacitance PC attached to column wire B1 is charged. Similarly, by turning switch SW2 into a conductive state, the parasitic capacitance PC attached to column wire B2 is charged, and by turning switch SWn into a conductive state, the parasitic capacitance PC attached to column wire Bn is charged. Here, it is desirable to charge the parasitic capacitance PC of each column wire B by turning one switch SW corresponding to each column wire B into a conductive state for a time longer than the time it takes for almost all of the charge of one capacitance element CP corresponding to each column wire B to be discharged. Specifically, it is desirable to charge the parasitic capacitance PC of column wire B1 by turning switch SW1 into a conductive state for a time longer than five times the product of the capacitance value of capacitance element CP1 and the resistance value of switch SW1, i.e., five times the time constant. If switch SW1 is kept in the conductive state for a time equal to five times the product of the capacitance value of capacitive element CP1 and the resistance value of switch SW1, 99.3% of the charge of capacitive element CP1 will be discharged.Similarly, it is desirable to charge the parasitic capacitance PC of column wire B2 by keeping switch SW2 in a conductive state for a time longer than five times the product of the capacitance value of capacitive element CP2 and the resistance value of switch SW2, and to charge the parasitic capacitance PC of column wire Bn by keeping switch SWn in a conductive state for a time longer than five times the product of the capacitance value of capacitive element CPn and the resistance value of switch SWn. Furthermore, it is desirable to charge the parasitic capacitance PC of each column wire B by keeping switch SW corresponding to each column wire B in a conductive state for a time longer than five times the product of the capacitance value of the parasitic capacitance PC of each column wire B and the resistance value of one switch SW corresponding to each column wire B. This is because the parasitic capacitance PC of each column wire B is sufficiently charged, and the output voltage caused by each of the selective resistors RS can be accurately measured. It is desirable to charge the parasitic capacitance PC of column wire B1 by keeping switch SW1 in a conductive state for a time longer than five times the product of the capacitance value of the parasitic capacitance PC of column wire B1 and the resistance value of switch SW1, i.e., five times the time constant. Similarly, it is desirable to charge the parasitic capacitance PC of column wire B2 by keeping switch SW2 in a conductive state for a time longer than five times the product of the capacitance value of the parasitic capacitance PC of column wire B2 and the resistance value of switch SW2, and it is desirable to charge the parasitic capacitance PC of column wire Bn by keeping switch SWn in a conductive state for a time longer than five times the product of the capacitance value of the parasitic capacitance PC of column wire Bn and the resistance value of switch SWn.

[0034] Next, one switch SW corresponding to each column line B is de-conducted (step S104). This completes the charging of the parasitic capacitance PC of each column line B, which has its corresponding switch SW in the conductive state. In the example in Figure 1, switch SW1 corresponding to column line B1 is switched to the de-conducting state. Similarly, switch SW2 corresponding to column line B2 is switched to the de-conducting state, and switch SWn corresponding to column line Bn is switched to the de-conducting state. At this time, the potential of the negative input terminal T2 of each operational amplifier OP is the second voltage V2, so a voltage difference between the first voltage V1 and the second voltage V2 (V2-V1) is applied to the resistor elements R(1,1) to R(1,n), and a current dependent on the resistance value of each resistor element R(1,1) to R(1,n) flows through each resistor element R(1,1) to R(1,n), flows through each column line B1 to Bn, and flows towards each capacitor element CP1 to CPn. In contrast, a second voltage V2 is applied to each of the other wax wires A2 to Am and column wires B1 to Bn, excluding the selectable wax wire A1. As a result, the voltage applied to the other resistive elements R, excluding the selectable resistive elements R(1,1) to R(1,n), becomes 0, and therefore no current flows through the other resistive elements R, excluding R(1,1) to R(1,n).

[0035] Next, the output voltage corresponding to each selective resistor RS is measured (step S105). Specifically, the output voltage from the output terminal T3 of one operational amplifier OP corresponding to each column B, due to the selective resistor RS connected to both the selective wax wire AS and each column wire B, is measured. In the example in Figure 1, the output voltage Vout from the output terminal T3 of operational amplifier OP1 corresponding to the resistor R(1,1) connected to both wax wire A1 and column wire B1 is measured. Similarly, the output voltage Vout from the output terminal T3 of operational amplifier OP2 corresponding to the resistor R(1,2) connected to both wax wire A1 and column wire B2 is measured, and the output voltage Vout from the output terminal T3 of operational amplifier OPn corresponding to the resistor R(1,n) connected to both wax wire A1 and column wire Bn is measured. The current flowing through each of the column wires B1 to Bn is converted into voltage by each of the capacitive elements CP1 to CPn, and output as the output voltage Vout from the output terminal T3 of operational amplifiers OP1 to OPn corresponding to each of the resistors R(1,1) to R(1,n). The output voltage Vout can be written as shown in equation (1) below.

[0036] Vout[V]={(V2[V]-V1[V]) / (cs[F]×rs[Ω])}×T[sec.]+V2[V] ……(1) Here, V1[V]: This is the first voltage applied to the selected wax wire AS. V2[V]: This is the second voltage applied to the positive input terminal T1. cs[F]: This is the capacitance value of one capacitance element CP corresponding to each column line B. rs[Ω]: This is the resistance value of one selective resistor RS corresponding to each column line B. T[sec.]: This is the elapsed time since one switch SW corresponding to each column line B was de-conducted. Vout[V]: This is the output voltage of one operational amplifier OP corresponding to each column line B after T[sec.] has elapsed.

[0037] Figure 4 is an explanatory diagram illustrating the change in output voltage Vout from the output terminal T3 of the operational amplifier OP1 in the element array circuit 1. The horizontal axis of Figure 4 represents time t, and the vertical axis represents the output voltage Vout. In Figure 4, time t0 is the time when switch SW1 is switched to the conductive state in step S103, and charging of the parasitic capacitance PC of column wire B1 begins. In Figure 4, time t1 is the time when switch SW1 is switched to the non-conductive state in step S104, and charging of the parasitic capacitance PC of column wire B1 ends. Therefore, the time from time t0 to time t1 is the charging time of the parasitic capacitance PC of column wire B1. In Figure 4, time t2 is the time when the output voltage Vout_t2 is measured after time T has elapsed from time t1. The example shown in Figure 4 is one in which the first voltage V1 is greater than the second voltage V2, and the output voltage Vout gradually decreases as time progresses from time t1. Since the capacitance value cs[F] of the capacitive element CP is known, the output voltage Vout depends on the resistance value rs[Ω] of the selective resistor RS, as shown in equation (1). Therefore, based on equation (1) above, the resistance value rs of each selective resistor RS can be calculated from the output voltage Vout_t2 at time t2.

[0038] With the above steps completed, the measurement operation in the element array circuit 1 is finished. When measuring the output voltage Vout corresponding to other resistive elements R other than resistive elements R(1,1) to R(1,n), repeat steps S101 to S105 above. However, for column wire B to which the already measured resistive elements R are connected, the operation of recharging its parasitic capacitance may be omitted. Also, in this embodiment, the order of steps S102 and S103 may be reversed, or step S102 may be placed between steps S104 and S105.

[0039] [Effects of element array circuit 1] As described above, the element array circuit 1 of this embodiment comprises one or more wax wires A, multiple column wires B, multiple resistor elements R, one or more operational amplifiers OP, one or more capacitive elements CP, and one or more switches SW. The multiple column wires B each extend in a direction different from the one or more wax wires A. The multiple resistor elements R are one or more no ro Each is connected to both one of the U-line A and one of the multiple column lines B. One or more operational amplifiers OP have a positive input terminal T1, a negative input terminal T2 that can be connected to one of the multiple column lines B, and an output terminal T3. One or more capacitive elements CP are Of the one or more operational amplifiers (OPs), one corresponding operational amplifier (OP) It is connected to the negative input terminal T2 and the output terminal T3, and converts the current flowing through column wire B, which is connected to the negative input terminal T2, into a voltage. One or more switches SW are, Of the one or more operational amplifiers (OPs), one corresponding operational amplifier (OP) A capacitive element CP is connected in parallel between the negative input terminal T2 and the output terminal T3, allowing it to switch between a conductive and non-conductive state. In an element array circuit 1 with this configuration, by setting one switch SW corresponding to each column line B to a conductive state, the column line B connected to the negative input terminal T2 of the corresponding operational amplifier OP and the output terminal T3 of the corresponding operational amplifier OP are connected, thereby quickly charging the parasitic capacitance attached to the column line B connected to the negative input terminal T2 of the corresponding operational amplifier OP. After this charging, the switch SW is switched to a non-conductive state, and the output voltage Vout from the output terminal T3 of the operational amplifier OP corresponding to each of the selective resistor elements RS can be measured.

[0040] However, in the infrared detection circuit of the aforementioned Patent Document 1, for example, the resistive element (resistor Rt mnA low-pass filter is formed by the parasitic capacitance of the resistor element and the wiring connected to the negative input terminal of the operational amplifier. Due to the effect of this low-pass filter, it takes a long time for the potential of the negative input terminal of the operational amplifier to which the wiring is connected to to reach a steady state as the parasitic capacitance charges, and it may also take a long time for the output voltage value due to the resistor element to reach a steady state. Therefore, in order to accurately measure the resistance value of the resistor element, it is necessary to wait a long time until the output voltage value reaches a steady state. Although it is possible to measure the output voltage value before it reaches a steady state, the accuracy of the measurement will be reduced.

[0041] In this respect, the element array circuit 1 of this embodiment is provided with a switch SW, which allows for rapid charging of the parasitic capacitances associated with each column wire B. Therefore, the output voltage Vout caused by the selective resistor RS connected to each column wire B can be quickly brought to a steady state, and the output voltage Vout related to the resistance value of each selective resistor RS can be measured quickly and accurately.

[0042] Furthermore, the element array circuit 1 of this embodiment is equipped with multiple operational amplifiers OP, with one operational amplifier OP corresponding to each of the multiple column lines B. Therefore, compared to, for example, the case where each of the multiple column lines B is selectively connected to a single operational amplifier OP and the output voltage Vout is measured, the output voltage Vout can be measured more quickly.

[0043] <2. Second Embodiment> [Example of the overall configuration of element array circuit 2] Figure 5 is a schematic circuit diagram showing an example of the overall configuration of an element array circuit 2 according to the second embodiment of the present invention. As shown in Figure 5, the configuration of the element array circuit 2 is substantially the same as the configuration of the element array circuit 1 of the first embodiment shown in Figure 1, except that multiple resistors RE (denoted as RE1 to REn in Figure 5) are used instead of multiple capacitive elements CP as multiple conversion elements. Therefore, the following description will mainly focus on the resistors RE, and descriptions of other components will be omitted as appropriate.

[0044] (Resistor element RE) Resistor element RE is a specific example corresponding to the "conversion element" and "first resistor element" of the present invention. Resistor element RE includes, for example, a resistor made of a metallic material having a predetermined resistivity. Each of the multiple resistor elements RE is connected to both the negative input terminal T2 and the output terminal T3 of a corresponding operational amplifier OP, and converts the current flowing through column wire B connected to the negative input terminal T2 into a voltage. Specifically, in the example in Figure 5, resistor element RE1 is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OP1, and converts the current flowing through column wire B1 into a voltage. Similarly, resistor element RE2 is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OP2, and converts the current flowing through column wire B2 into a voltage, and resistor element REn is connected to both the negative input terminal T2 and the output terminal T3 of operational amplifier OPn, and converts the current flowing through column wire Bn into a voltage. The resistance value of each of the multiple resistor elements RE is greater than the resistance value of the corresponding switch SW.

[0045] [Measurement operation in element array circuit 2] In the element array circuit 2, measurements can be taken for each of the multiple resistor elements R, for example, as shown below. Note that the following measurement operations are performed by commands from the control unit CTRL.

[0046] The measurement operation of element array circuit 2 is basically the same as that of element array circuit 1 (see Figure 2). That is, as shown in the flowchart of Figure 2, the parasitic capacitances attached to each column line B are quickly charged before the measurement of the resistive element R is performed (step S103). Specifically, in the example of Figure 5, switch SW1 corresponding to column line B1 to which the resistive element R(1,1) as a selective resistive element RS is connected is made conductive, and the negative input terminal T2 and output terminal T3 of the operational amplifier OP1 are made conductive. Similarly, switch SW2 corresponding to column line B2 to which the resistive element R(1,2) as a selective resistive element RS is connected is made conductive, and the negative input terminal T2 and output terminal T3 of the operational amplifier OP2 are made conductive. Switch SWn corresponding to column line Bn to which the resistive element R(1,n) as a selective resistive element RS is connected is made conductive, and the negative input terminal T2 and output terminal T3 of the operational amplifier OPn are made conductive. This charges the parasitic capacitances of column wire B1, column wire B2, and column wire Bn, respectively. Here, as in the first embodiment, the time for charging the parasitic capacitance PC of each column wire B by keeping one switch SW corresponding to each column wire B in a conductive state is preferably longer than five times the product of the capacitance value of the parasitic capacitance PC of each column wire B and the resistance value of the one switch SW corresponding to each column wire B.

[0047] Next, one switch SW corresponding to each column wire B is de-conducted (step S104). This completes the charging of the parasitic capacitance PC of each column wire B, which has its corresponding switch SW in the conductive state. In the example in Figure 5, switch SW1 corresponding to column wire B1 is switched to the de-conducting state. Similarly, switch SW2 corresponding to column wire B2 is switched to the de-conducting state, and switch SWn corresponding to column wire Bn is switched to the de-conducting state. At this time, a voltage (V2-V1) which is the difference between the first voltage V1 and the second voltage V2 is applied to the resistive elements R(1,1) to R(1,n), and a current dependent on the resistance value of each resistive element R(1,1) to R(1,n) flows through each of the resistive elements R(1,1) to R(1,n), flows through each of the column wires B1 to Bn, and flows through each of the resistive elements RE1 to REn. In Figure 5, the dashed arrows show how current flows through resistor RE1, depending on the resistance value of resistor R(1,1). In contrast, a second voltage V2 is applied to each of the other wax wires A2~Am and column wires B1~Bn, excluding the select wax wire A1. Therefore, the voltage applied to the other resistors R other than the select resistors R(1,1)~R(1,n) is 0, and no current flows through the other resistors R other than R(1,1)~R(1,n). Next, the output voltage corresponding to each select resistor RS is measured (step S105). Specifically, the output voltage from the output terminal T3 of one operational amplifier OP corresponding to each column wire B, which is caused by the select resistor RS connected to both the select wax wire AS and each column wire B, is measured. The currents flowing through column lines B1 to Bn are converted into voltages by resistors RE1 to REn, and these are output as output voltages Vout from the output terminals T3 of the operational amplifiers OP1 to OPn, which correspond to resistors R(1,1) to R(1,n). The output voltage Vout can be written as shown in equation (2) below.

[0048] Vout[V]=(re[Ω] / rs[Ω])×(V2[V]-V1[V])+V2[V] ……(2) Here, V1[V]: This is the first voltage applied to the selected wax wire AS. V2[V]: This is the second voltage applied to the positive input terminal T1. re[Ω]: This is the resistance value of one resistor RE corresponding to each column line B. rs[Ω]: This is the resistance value of one selective resistor RS corresponding to each column line B. Vout[V]: This is the output voltage of one operational amplifier OP corresponding to each column line B.

[0049] Since the resistance value re[Ω] of resistor element RE1 is known, the output voltage Vout depends on the resistance value rs[Ω] of the selective resistor element RS, as shown in equation (2). Therefore, based on equation (2) above, the resistance value rs of each selective resistor element RS can be calculated from the output voltage Vout.

[0050] [Effects of element array circuit 2] The element array circuit 2 of this embodiment can be expected to have the same effects as the element array circuit 1 of the first embodiment. That is, since the element array circuit 2 of this embodiment is provided with a switch SW, the parasitic capacitances attached to each column wire B can be charged quickly. Therefore, the output voltage Vout caused by the selective resistor RS connected to each column wire B can be quickly brought to a steady state, and the output voltage Vout related to the resistance value of each selective resistor RS can be measured quickly and accurately.

[0051] Furthermore, the element array circuit 2 of this embodiment is equipped with multiple operational amplifiers, with one operational amplifier OP corresponding to each of the multiple column lines B. Therefore, compared to, for example, the case where each of the multiple column lines B is selectively connected to a single operational amplifier OP and the output voltage Vout is measured, the output voltage Vout can be measured more quickly.

[0052] <3. Third Embodiment> [Example of the overall configuration of element array circuit 3] Figure 6 is a schematic circuit diagram showing an example configuration of an element array circuit 3 according to a third embodiment of the present invention. As shown in Figure 6, the configuration of the element array circuit 3 differs from the configuration of the element array circuit 1 in Figure 1 in that it further includes a column wire selection unit SB, and the number of switches SW, capacitive elements CP, and operational amplifiers OP is set to 1. Therefore, in the following description, the explanation will mainly focus on the column wire selection unit SB, and explanations of other components will be omitted as appropriate. Although Figure 6 illustrates a state in which m wax wires A are arranged, the number of wax wires A can be arbitrarily set. Similarly, although Figure 6 illustrates a state in which n column wires B are arranged, the number of column wires B can be arbitrarily set. In addition, in the example shown in Figure 6, one set of switches SW, capacitive elements CP, and operational amplifiers OP is provided for n column wires B, but two or more sets of switches SW, capacitive elements CP, and operational amplifiers OP may be provided for n column wires B.

[0053] (Column line selection section SB) The column wire selection unit SB has a plurality of switches SWB1 (SWB1-1 to SWB1-n) and a plurality of switches SWB2 (SWB2-1 to SWB2-n). Each of the plurality of switches SWB1 (SWB1-1 to SWB1-n) and SWB2 (SWB2-1 to SWB2-n) is capable of switching between a conductive state and a non-conductive state. Each of the plurality of switches SWB1 (SWB1-1 to SWB1-n) is provided between a corresponding column wire B (B1 to Bn) and the negative input terminal T2 of the operational amplifier OP. Each of the plurality of switches SWB2 (SWB2-1 to SWB2-n) is provided between a corresponding column wire B (B1 to Bn) and the DC power supply PS2.

[0054] The column line selection unit SB selects one of several column lines B (referred to as the selected column line BS for convenience) and connects this selected column line BS to the negative input terminal T2 of the operational amplifier OP. The column line selection unit SB also connects the other column lines B (referred to as the unselected column lines BU for convenience) to the DC power supply PS2 via several switches SWB2 (SWB2-1 to SWB2-n). The operation of the column line selection unit SB is controlled by the control unit CTRL. That is, the switching operations of the multiple switches SWB1 (SWB1-1 to SWB1-n) and multiple switches SWB2 (SWB2-1 to SWB2-n) in the column line selection unit SB are executed based on commands from the control unit CTRL.

[0055] [Measurement operation in element array circuit 3] In the element array circuit 3, measurements can be performed on each of the multiple resistor elements R, for example, as shown below. Note that the following measurement operations are performed by commands from the control unit CTRL.

[0056] Figure 7 is a flowchart illustrating the measurement operation of the element array circuit 3. First, all switches are set to a non-conductive state (step S301). Specifically, all of the switches shown in Figure 6—one switch SW, multiple switches SWA1 (SWA1-1 to SWA1-m), multiple switches SWA2 (SWA2-1 to SWA2-m), multiple switches SWB1 (SWB1-1 to SWB1-n), and multiple switches SWB2 (SWB2-1 to SWB2-n)—are set to a non-conductive state (open state).

[0057] Next, a selection wax wire AS corresponding to the selection resistance element RS to be measured is selected (step S302). This step S302 is performed in the same manner as step 102 in Figure 2 described in the first embodiment above.

[0058] Next, the selected column line BS corresponding to the selected resistance element RS to be measured is selected (step S303). Specifically, the switch SWB1 connected to the selected column line BS to which the selected resistance element RS is connected is set to conduct, and the selected column line BS is connected to the operational amplifier OP. The switch SWB1 corresponding to the non-selected column line BU is kept in a non-conducting state. Furthermore, the switch SWB2 of the non-selected column line BU is set to conduct, and a second voltage V2 is applied to the non-selected column line BU. The switch SWB2 corresponding to the selected column line BS is kept in a non-conducting state. The example in Figure 6 shows the state in which the resistance element R(1,1) is selected as the selected resistance element RS. That is, the switch SWB1-1 corresponding to column line B1 as the selected column line BS is set to conduct, and column line B1 is connected to the operational amplifier OP. On the other hand, the switches SWB1-2 to SWB1-n corresponding to column lines B2 to Bn as the non-selected column lines BU are kept in a non-conducting state. Furthermore, switches SWB2-2 to SWB2-n, which correspond to column lines B2 to Bn as non-selective column lines BU, are made conductive, and a second voltage V2 is applied to column lines B2 to Bn. On the other hand, switch SWB2-1, which corresponds to column line B1 as a selected column line BS, is kept non-conductive.

[0059] Next, switch SW is turned on (step S304) to charge the parasitic capacitance attached to the selection column line BS corresponding to the selection resistor element RS to be measured. Specifically, switch SWB1-1, which corresponds to column line B1 as the selection column line BS, is turned on, and switch SW is turned on, making the column line B1 and the output terminal T3 of the operational amplifier OP conductive. Figure 8 shows a circuit diagram illustrating the charging operation of the parasitic capacitance PC in the element array circuit 3. As shown by the dashed arrow in Figure 8, turning on switch SW charges the operational amplifier O PCurrent flows through column wire B1, and the parasitic capacitance PC attached to column wire B1 is charged. Here, it is desirable to charge the parasitic capacitance PC of the selected column wire BS by keeping the switch SW in the conductive state for a longer period of time than the time required for almost all of the charge of the capacitive element CP to be discharged. Specifically, it is desirable to charge the parasitic capacitance PC of the selected column wire BS by keeping the switch SW in the conductive state for a longer period of time than five times the product of the capacitance value of the capacitive element CP and the resistance value of the switch SW, i.e., five times the time constant. If the switch SW is kept in the conductive state for a time of five times the product of the capacitance value of the capacitive element CP and the resistance value of the switch SW, 99.3% of the charge of the capacitive element CP will be discharged. Furthermore, it is desirable to charge the parasitic capacitance PC of the selected column wire BS by keeping the switch SW in the conductive state for a longer period of time than five times the product of the capacitance value of the parasitic capacitance PC of the selected column wire BS and the resistance value of the switch SWB corresponding to the selected column wire BS (the resistance value when the switch SWB is in the conductive state). The parasitic capacitance PC of the selected column wire BS is sufficiently charged, and the output voltage Vout due to the selected resistor RS is positive. Because it can be measured accurately.

[0060] Next, the switch SW is de-conducted (step S305). This completes the charging of the parasitic capacitance PC of the selected column wire BS, which was in the conductive state when the switch SW was turned on. At this time, a voltage (V2-V1), which is the difference between the first voltage V1 and the second voltage V2, is applied to the resistive element R(1,1), and a current dependent on the resistance value of the resistive element R(1,1) flows through the resistive element R(1,1), through the column wire B1 as the selected column wire BS, and towards the capacitive element CP. In contrast, the second voltage V2 is applied to the other wax wires A2~Am and column wire B1, excluding the wax wire A1 which is the selected wax wire AS. Therefore, among the resistive elements R(1,1)~R(1,m) connected to the column wire B1 as the selected column wire BS, the voltage applied to the resistive elements R other than the resistive element R(1,1) which is the selected resistive element RS is 0, so no current flows through the resistive elements R(1,2)~R(1,m). Furthermore, the resistive element R connected to the column lines B2~Bn, which are non-selective column lines BU, is not connected to the capacitive element CP, so it does not affect the capacitive element CP.

[0061] Next, the output voltage corresponding to the selective resistor RS is measured (step S306). This step S306 is performed in the same manner as step 105 in Figure 2 described in the first embodiment above. In step S306, the output voltage Vout from the output terminal T3 of the operational amplifier OP is measured. As described in the first embodiment above, the resistance value rs of the selective resistor RS can be calculated from the output voltage Vout from the output terminal T3 of the operational amplifier OP based on equation (1). However, in this embodiment, in equation (1), cs[F] is read as the capacitance value of the capacitive element CP, rs[Ω] is read as the resistance value of one selective resistor RS corresponding to the selective column line BS, T[sec.] is read as the elapsed time since the switch SW was in a non-conductive state, and Vout[V] is read as the output voltage of the operational amplifier OP after T[sec.] has elapsed.

[0062] With the above steps completed, the measurement operation in the element array circuit 3 is finished. When measuring the output voltage Vout corresponding to a resistor R other than resistor R(1,1), repeat steps S301 to S306 above. However, for column wire B to which a resistor R that has already been measured is connected, the operation to recharge its parasitic capacitance may be omitted. Also, in the example in Figure 6, the first end of the non-selective column wire BU is connected to the DC power supply PS2 via switch SWB2, so the parasitic capacitance of the non-selective column wire BU can be charged to some extent by the current from the DC power supply PS2. However, a slight error (offset voltage) may occur between the second voltage V2 applied from the DC power supply PS2 and the potential of the negative input terminal T2, and due to this error, charging the parasitic capacitance of the non-selective column wire BU by the current from the DC power supply PS2 may be insufficient. For this reason, in order to perform measurements with higher accuracy, the operation to charge the parasitic capacitance of the selected column wire BS by conducting the switch SW each time the selected column wire BS is selected may be performed. Furthermore, in this embodiment, the order of steps S302 to S305 may be arbitrarily rearranged under the conditions that "step S303 is performed before step S305" and "step S304 is performed before step S305". Specifically, the order of steps S302 to S305 may be S302→S304→S303→S305, S303→S302→S304→S305, S303→S304→S302→S305, S303→S304→S305→S302, S304→S302→S303→S305, S304→S303→S302→S305, or S304→S303→S305→S302. If step S304 occurs before step S303, charging of the parasitic capacitance PC of column B designated as the selected column B begins when switch SW is turned to the conductive state and switch SWB1 corresponding to column B designated as the selected column B is turned to the conductive state.Furthermore, in the example in Figure 6, the first end of the non-selective column wire BU is connected to the DC power supply PS2 via the switch SWB2. However, the connection destination of the first end of the non-selective column wire BU does not matter as long as the non-selective column wire BU is not connected to the capacitive element CP and no current flows between the non-selective column wire BU and the capacitive element CP.

[0063] [Effects of element array circuit 3] In the element array circuit 3 of this embodiment, the same effects as in the element array circuit 1 of the first embodiment can be expected. That is, in the element array circuit 3 of this embodiment, a switch SW is provided, so that the parasitic capacitance parasitic to the selection column line BS can be charged quickly. Therefore, the output voltage Vout caused by the selection resistor RS connected to the selection column line BS can be quickly brought to a steady state, and the output voltage Vout related to the resistance value of the selection resistor RS can be measured quickly and accurately.

[0064] Furthermore, in the element array circuit 3 of this embodiment, the column wire selection unit SB is used to selectively connect each of the multiple column wires B to one operational amplifier OP, thus the above-mentioned circuit equipped with multiple operational amplifiers OP 1 Compared to the element array circuit 1 of the previous embodiment, this design can be made more compact.

[0065] <4. Fourth Embodiment> [Example of the overall configuration of element array circuit 4] Figure 9 is a schematic circuit diagram showing an example of the configuration of an element array circuit 4 according to the fourth embodiment of the present invention. As shown in Figure 9, the configuration of the element array circuit 4 is substantially the same as the configuration of the element array circuit 3 of the third embodiment shown in Figure 6, except that a resistive element RE is used instead of a capacitive element CP as one conversion element. In Figure 9, a state in which m wax wires A are arranged is illustrated, but the number of wax wires A can be set arbitrarily. Similarly, in Figure 9, a state in which n column wires B are arranged is illustrated, but the number of column wires B can be set arbitrarily. In addition, in the example shown in Figure 9, a switch SW is connected to the n column wires B. Click the resistor button RE A set of , and an operational amplifier OP is provided, but a switch SW is provided for n column wires B, Click the resistor button RE And two or more pairs of operational amplifiers (OP) may be provided.

[0066] Furthermore, the measurement operation of the element array circuit 4 in this embodiment can also be performed in accordance with the procedure (steps S301 to S306) described in the third embodiment with reference to Figure 7. Similar to the third embodiment, the time for charging the parasitic capacitance PC of the selection column line BS with the switch SW in a conductive state should be longer than 5 times the product of the capacitance value of the parasitic capacitance PC and the sum of the resistance value of the switch SW and the resistance value of the switch SWB corresponding to the selection column line BS. Also, in step S306, the output voltage Vout from the output terminal T3 of the operational amplifier OP is measured. As described in the second embodiment, the resistance value rs of the selection resistor RS can be calculated from the output voltage Vout from the output terminal T3 of the operational amplifier OP based on equation (2). However, in this embodiment, in equation (2), re[Ω] is read as the resistance value of the resistor RE, rs[Ω] is read as the resistance value of one selection resistor RS corresponding to the selection column line BS, and Vout[V] is read as the output voltage of the operational amplifier OP.

[0067] [Effects of element array circuit 4] In the element array circuit 4 of this embodiment, the same effects as in the element array circuit 3 of the third embodiment can be expected. That is, in the element array circuit 4 of this embodiment, a switch SW is provided, so that the parasitic capacitance parasitic to the selection column wire BS can be charged quickly. Therefore, the output voltage Vout caused by the selection resistor RS connected to the selection column wire BS can be quickly brought to a steady state, and the output voltage Vout related to the resistance value of the selection resistor RS can be measured quickly and accurately.

[0068] Furthermore, in the element array circuit 4 of this embodiment, a column wire selection unit SB is used to selectively connect each of the multiple column wires B to one operational amplifier OP, so the above-mentioned configuration with multiple operational amplifiers OP 2 Compared to the element array circuit 2 of the previous embodiment, this design can be made more compact.

[0069] <5. Fifth Embodiment> Figure 10 is a schematic diagram illustrating an example of the configuration of a sensor device 101 equipped with an element array circuit of the present invention. As shown in Figure 10, the sensor device 101 comprises a detection unit 10, a calculation unit 20, a storage unit 30, and an output unit 40. The sensor device 101 is, for example, an electromagnetic wave sensor that detects the intensity of electromagnetic waves to be received. Note that the configuration of the sensor device 101 shown in Figure 10 is just one example and is not limited thereto.

[0070] The detection unit 10 has at least one of the element array circuits 1 to 4 described in the first to fourth embodiments above. The detection unit 10 is, for example, an infrared detection unit that receives infrared light and outputs a voltage that changes according to the intensity of the received infrared light. However, the detection unit 10 may also receive electromagnetic waves other than infrared light (for example, terahertz waves) and output a voltage that changes according to the intensity of the received electromagnetic waves.

[0071] The calculation unit 20 receives the output voltage from the detection unit 10 and performs calculations such as converting it into data of desired parameters. The storage unit 30 stores the data generated by the calculation unit 20. The output unit 40 outputs the data generated by the calculation unit 20 as an electrical signal to an external device.

[0072] According to the sensor device 101 of this embodiment, since it is equipped with a detection unit 10 having at least one of the element array circuits 1 to 4, the intensity of the electromagnetic waves to be received can be measured quickly and accurately.

[0073] In this example, the resistive element R in the detection unit 10 is shown as a light-receiving element that converts electromagnetic waves such as infrared rays into electrical signals, but the sensor device 101 of this embodiment is not limited to this case.

[0074] For example, a thermosensitive resistor made of a thermistor material or a temperature-sensitive conductive ink material may be used as the resistive element R in the element array circuits 1 to 4 of the detection unit 10. Such a thermosensitive resistor is designed so that its electrical resistance changes depending on the temperature. In that case, the sensor device 101 becomes a temperature sensor capable of detecting the temperature distribution within a plane.

[0075] Alternatively, pressure-sensitive elements made of pressure-sensitive conductive ink material or the like may be used as the resistive elements R in the element array circuits 1 to 4 of the detection unit 10. Such pressure-sensitive elements are configured so that their electrical resistance changes according to the intensity of the applied pressure. The sensor device 101, which includes a detection unit 10 that uses pressure-sensitive elements as resistive elements R, becomes a pressure sensor capable of detecting the pressure distribution in a plane.

[0076] Furthermore, strain gauges may be used as the resistive elements R in the element array circuits 1 to 4 of the detection unit 10. Such strain gauges are configured so that their electrical resistance changes according to the intensity of the applied stress. A sensor device 101 equipped with a detection unit 10 that uses strain gauges as resistive elements R becomes a strain sensor capable of detecting the stress distribution in a plane.

[0077] <6. Variation> Although this disclosure has been described with reference to several embodiments, it is not limited to these embodiments, and various modifications are possible.

[0078] For example, the drawings illustrating the element array circuits 1 to 4 of the first to fourth embodiments above illustrate a case where the extension directions of the multiple wax wires are parallel to each other, but the present invention is not limited to this, and the multiple wax wires may be non-parallel to each other. Furthermore, the multiple wax wires are not limited to extending in a straight line, but may extend in a curved shape overall, or may have a shape that includes curved or bent portions in part. Similarly, the drawings illustrating the element array circuits 1 to 4 illustrate a case where the extension directions of the multiple column wires are parallel to each other, but the present invention is not limited to this, and the multiple column wires may be non-parallel to each other. Furthermore, the present invention is not limited to a case where the multiple wax wires and multiple column wires extend in directions perpendicular to each other. Moreover, the multiple column wires are not limited to extending in a straight line, but may extend in a curved shape overall, or may have a shape that includes curved or bent portions in part.

[0079] Furthermore, although the element array circuits 1 to 4 in the first to fourth embodiments described above have multiple wax wires and multiple column wires, the present invention is not limited thereto. For example, the element array circuit 3A shown in Figure 11 is equipped with only one wax wire A. The configuration of the element array circuit 3A is substantially the same as that of the element array circuit 3 (Figure 8), except that it has only one wax wire A instead of multiple wax wires A1 to Am and does not have a wax wire selection unit SA. Also, the element array circuit 1A shown in Figure 12 is equipped with only one column wire B. The configuration of the element array circuit 1A is substantially the same as that of the element array circuit 1, except that it has only one column wire B instead of multiple columns B1 to Bn.

[0080] Furthermore, while the element array circuits 1 to 4 in the first to fourth embodiments described above have multiple resistive elements R as multiple impedance elements, the present invention is not limited thereto. For example, the element array circuit 1B shown in Figure 13 has multiple semiconductor elements SC. The configuration of element array circuit 1B is substantially the same as that of element array circuit 1, except that it has multiple semiconductor elements SC instead of multiple resistive elements R. The semiconductor elements SC are, for example, those whose electrical characteristics change with temperature, such as diodes. For example, instead of the thermistor film given as an example of resistive element R in the first embodiment, a diode whose impedance value changes with temperature may be used, and the temperature in the diode may be detected as an output voltage due to the impedance value of the diode. This can be applied to an electromagnetic wave sensor that detects the intensity of electromagnetic waves such as infrared rays, or a temperature sensor that can detect the temperature distribution in a plane.

[0081] Furthermore, although the element array circuits 1 to 4 of the first to fourth embodiments described above have one or more capacitive elements CP or one or more resistive elements RE as one or more conversion elements, the present invention is not limited thereto, and for example, one or more semiconductor elements may be used. For example, as shown in the element array circuit 1C in Figure 14, there may be multiple diodes D as multiple conversion elements. In the example shown in Figure 14, currents dependent on the resistance values ​​of each of the resistive elements R(1,1) to R(1,n) flow through each of the resistive elements R(1,1) to R(1,n), through each of the column lines B1 to Bn, and through each of the diodes D1 to Dn. The currents flowing through each of the column lines B1 to Bn are converted into voltages by each of the diodes D1 to Dn according to the current-voltage characteristics of each of the diodes D1 to Dn, and output as output voltages Vout from the output terminals T3 of the operational amplifiers OP1 to OPn corresponding to each of the resistive elements R(1,1) to R(1,n).

[0082] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur. [Explanation of Symbols]

[0083] 1...Element array circuit, A(A1~Am)...Wax wire, B(B1~Bn)...Column wire, CTRL...Control unit, CP(CP1~CPn)...Capacitor element, OP(OP1~OPn)...Operational amplifier, PS1,PS2...DC power supply, R(R(1,1)~R(m,n))...Resistor element, SA...Wax wire selection unit, SW(SW1~SWn)...Switch.

Claims

1. One or more first wires and A plurality of second wirings, each extending in a direction different from each of the one or more first wirings, Multiple impedance elements, each connected to one of the one or more first wirings and one of the multiple second wirings, Each of the operational amplifiers has a positive input terminal, a negative input terminal connectable to one of the plurality of second wirings, and an output terminal. Each of the above one or more operational amplifiers is connected to the negative input terminal and the output terminal of a corresponding operational amplifier, and one or more conversion elements convert the current flowing through one of the plurality of second wires connected to the negative input terminal into a voltage, Each of the above includes one or more switching units that are connected in parallel with one of the above one or more conversion elements between the negative input terminal and the output terminal of a corresponding operational amplifier from among the one or more operational amplifiers, and that can take on a conduction state and a non-conduction state, A control unit that performs control to switch one of the one or more switching units to a non-conductive state by making one of the plurality of second wirings corresponding to the one switching unit conductive, thereby making one of the plurality of second wirings corresponding to the one switching unit conductive and the output terminal of the one operational amplifier corresponding to the one switching unit conductive, thereby charging the parasitic capacitance attached to one of the plurality of second wirings corresponding to the one switching unit, and then switching the one switching unit to a non-conductive state. Equipped with Element array circuit.

2. After charging the parasitic capacitance, the control unit switches one of the one or more switching units corresponding to the negative input terminal to the non-conductive state, and then measures the output voltage from the output terminal caused by one of the plurality of impedance elements connected to both one of the one or more first wirings and one of the plurality of second wirings connected to the negative input terminal. The element array circuit according to claim 1.

3. The one or more conversion elements are one or more capacitive elements. The time for charging the parasitic capacitance by making one of the one or more switching units corresponding to the negative input terminal conductive is longer than five times the product of the capacitance value of one of the one or more capacitive elements corresponding to the negative input terminal and the resistance value of the one of the one or more switching units corresponding to the negative input terminal. The element array circuit according to claim 2.

4. One or more first wirings, A plurality of second wirings, each extending in a direction different from each of the one or more first wirings, Multiple impedance elements, each connected to one of the one or more first wirings and one of the multiple second wirings, Each of the operational amplifiers has a positive input terminal, a negative input terminal connectable to one of the plurality of second wirings, and an output terminal. Each of the above one or more operational amplifiers is connected to the negative input terminal and the output terminal of a corresponding operational amplifier, and one or more conversion elements convert the current flowing through one of the plurality of second wires connected to the negative input terminal into a voltage, Each of the above includes one or more switching units that are connected in parallel with one of the above one or more conversion elements between the negative input terminal and the output terminal of a corresponding operational amplifier from among the one or more operational amplifiers, and that can take on a conduction state and a non-conduction state, A second wiring selection unit that selects one of the plurality of second wirings and connects it to the negative input terminal, A control unit that performs control to switch one of the one or more switching units to a non-conductive state by making one of the plurality of second wirings corresponding to the one switching unit conductive, thereby making one of the plurality of second wirings corresponding to the one switching unit conductive and the output terminal of the one operational amplifier corresponding to the one switching unit conductive, thereby charging the parasitic capacitance attached to one of the plurality of second wirings corresponding to the one switching unit, and then switching the one switching unit to a non-conductive state. Equipped with, The time required to charge the parasitic capacitance by keeping one of the switching units in a conductive state is longer than five times the product of the capacitance value of the parasitic capacitance and the sum of the resistance value of the one switching unit and the resistance value of the second wiring selection unit. Element array circuit.

5. One or more first wirings, A plurality of second wirings, each extending in a direction different from each of the one or more first wirings, Multiple impedance elements, each connected to one of the one or more first wirings and one of the multiple second wirings, Each of the multiple operational amplifiers has a positive input terminal, a negative input terminal connectable to one of the multiple second wirings, and an output terminal. Each of the plurality of conversion elements is connected to the negative input terminal and the output terminal of a corresponding operational amplifier among the plurality of operational amplifiers, and converts the current flowing through one of the plurality of second wires connected to the negative input terminal into a voltage. Each of the multiple switching units is connected in parallel with one of the multiple conversion elements between the negative input terminal and the output terminal of a corresponding operational amplifier among the multiple operational amplifiers, and is capable of taking on a conduction state and a non-conduction state. A control unit that performs control to switch one of the plurality of switching units to a non-conductive state by making one of the plurality of second wirings corresponding to the one switching unit conductive, thereby making one of the plurality of second wirings corresponding to the one switching unit conductive and the output terminal of the one operational amplifier corresponding to the one switching unit conductive, thereby charging the parasitic capacitance attached to one of the plurality of second wirings corresponding to the one switching unit, and then switching the one switching unit to a non-conductive state. Equipped with, The time for charging the parasitic capacitance by making one of the multiple switching units corresponding to the negative input terminal conductive is longer than five times the product of the capacitance value of the parasitic capacitance and the resistance value of the one switching unit. Element array circuit.

6. Multiple first wires and One or more second wirings, each extending in a direction different from each of the plurality of first wirings, Each of the plurality of impedance elements is connected to both one of the plurality of first wirings and one of the one or more second wirings, One or more operational amplifiers having a positive input terminal, a negative input terminal connectable to one of the one or more second wirings, and an output terminal, Each is connected to the negative input terminal and the output terminal of a corresponding operational amplifier among the one or more operational amplifiers, and one or more conversion elements that convert the current flowing through one of the one or more second wirings connected to the negative input terminal into a voltage, Each of the above includes one or more switching units that are connected in parallel with one of the above one or more conversion elements between the negative input terminal and the output terminal of a corresponding operational amplifier from among the one or more operational amplifiers, and that can take on a conduction state and a non-conduction state, A control unit that performs control to switch one of the one or more switching units to a non-conductive state by making one of the one or more second wirings corresponding to the one switching unit conductive, thereby making one of the one or more second wirings corresponding to the one switching unit conductive and the output terminal of the one operational amplifier corresponding to the one switching unit conductive, thereby charging the parasitic capacitance attached to one of the one or more second wirings corresponding to the one switching unit, and then switching the one switching unit to a non-conductive state. Equipped with Element array circuit.

7. After charging the parasitic capacitance, the control unit switches one of the one or more switching units corresponding to the negative input terminal to the non-conductive state, and then measures the output voltage from the output terminal caused by one of the multiple impedance elements connected to both one of the multiple first wirings and one of the one or more second wirings connected to the negative input terminal. The element array circuit according to claim 6.

8. The time for charging the parasitic capacitance by making one of the one or more switching units corresponding to the negative input terminal conductive is longer than five times the product of the capacitance value of the parasitic capacitance and the resistance value of the one of the one or more switching units corresponding to the negative input terminal. The element array circuit according to claim 6.

9. The one or more conversion elements are one or more capacitive elements. The time for charging the parasitic capacitance by making one of the one or more switching units corresponding to the negative input terminal conductive is longer than five times the product of the capacitance value of one of the one or more capacitive elements corresponding to the negative input terminal and the resistance value of the one of the one or more switching units corresponding to the negative input terminal. The element array circuit according to claim 6.

10. The one or more first wirings are a plurality of first wirings, Each of the plurality of impedance elements is connected to one of the plurality of first wirings, It is connected to both the first and second wirings and one of the plurality of second wirings. The element array circuit according to any one of claims 1 to 9.

11. Each of the one or more conversion elements is a capacitive element, a first resistive element, or a first semiconductor element. The element array circuit according to any one of claims 1 to 9.

12. Each of the aforementioned plurality of impedance elements is either a second resistive element or a second semiconductor element. The element array circuit according to any one of claims 1 to 9.

13. An electromagnetic wave sensor having an element array circuit according to any one of claims 1 to 9.

14. A temperature sensor having an element array circuit according to any one of claims 1 to 9.

15. A strain sensor having an element array circuit according to any one of claims 1 to 9.

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