WO2021201247A1

WO2021201247A1 - Signal detection circuit, drive/detection circuit, sensor array, and sensor system

Info

Publication number: WO2021201247A1
Application number: PCT/JP2021/014220
Authority: WO
Inventors: 守石▲崎▼
Original assignee: 凸版印刷株式会社
Priority date: 2020-04-03
Filing date: 2021-04-01
Publication date: 2021-10-07
Also published as: JPWO2021201247A1

Abstract

Provided is a smaller-scale signal detection circuit. Also provided is a drive/detection circuit constructed by including a drive circuit and a control circuit in the signal detection circuit, the drive/detection circuit having a smaller scale and making fewer errors. The signal detection circuit is for a sensor array that detects external stimuli to sensors corresponding to intersections of a matrix of scanning lines and signal lines. In the signal detection circuit, a group of Ｍ１ signal lines make up each of Ｍ２ blocks, and Ｍ２ blocks each house a first switching circuit having input terminals connected to Ｍ１ signal lines, and a load resistance and a voltage detection amplifier that are connected to an output terminal of the first switching circuit. The signal detection circuit includes a second switching circuit having input terminals connected respectively to output terminals of Ｍ２ blocks, and an AD converter connected to an output terminal of the second switching circuit.

Description

Signal detection circuit, drive detection circuit, sensor array and sensor system

The present disclosure relates to signal detection circuits, drive detection circuits, sensor arrays and sensor systems.

In recent years, people's interest in health has increased, and progress in the healthcare field is expected. Along with this, it is important to arrange the sensors in an array to obtain information on external stimulus values such as pressure and temperature in two dimensions in order to grasp a person's posture, movement, abnormality, and the like. For example, an in-plane pressure distribution can be detected by using a pressure sensor array that combines a thin film transistor array and a pressure sensitive medium. As the pressure-sensitive medium, there are those whose resistance changes depending on the pressure (Patent Document 1) and those whose potential difference changes depending on the pressure (Patent Document 2). Alternatively, an in-plane temperature distribution can be detected by using a temperature sensor array that combines a thin film transistor array and a temperature sensitive medium.

A sensor array usually has detection points (referred to as "pixels") corresponding to intersections of a plurality of scanning wires and a plurality of signal wires, and a circuit that detects a signal from the sensor array when the number of signal wires increases. Will also grow in scale. The most easily conceivable signal detection circuit is to provide the same number of load resistors 122, voltage detection amplifier 123, and AD converter 124 as the number of signal wiring 115 as shown in FIG. 29, but requires a large area and cost. ..

Therefore, as a method of reducing the scale of the signal detection circuit, it has been proposed to reduce the number of circuits on the downstream side by applying the switching circuit 100 as shown in FIG. The signal detection circuit inputs the outputs of the plurality of signal wirings 115 to one switching circuit 100 after passing through the voltage detection amplifier 123, and outputs the output of one switching circuit 100 to one AD converter 124. I'm typing. For example, in the circuit described in Patent Document 3, the outputs from a plurality of electrodes are input to one multiplexer after passing through an operational amplifier, and the output of the one multiplexer is input to one A / D converter. You are typing. Further, an example of a drive circuit including a signal detection circuit as shown in FIG. 30 is shown in FIG. The drive detection circuit of FIG. 31 is obtained by adding a control circuit 125 and a drive circuit 126 to the signal detection circuit of FIG. 30, and detects a signal at a sensor point by applying an on-voltage to the scanning wiring 127. .. In Patent Document 4, a large number of signal wiring outputs are input to a small number of switching circuits after passing through a voltage detection amplifier, and are input to the same number of AD converters as the switching circuits. According to these, the number of voltage detection amplifiers and load resistors is not reduced, but the number of AD converters can be reduced.

Japanese Unexamined Patent Publication No. 2014-119375 Japanese Patent No. 2943437 Japanese Patent No. 4160251 Japanese Patent No. 3667058

However, in these circuits, although the number of AD converters on the downstream side of the switching circuit can be reduced, the same number of voltage detection amplifiers and load resistors on the upstream side of the switching circuit must be prepared as the number of signal wirings. There was a problem that the scale of the entire detection circuit could not be reduced very much.

The present disclosure has been made in view of the situation of the prior art, and an object of the present invention is to provide a signal detection circuit having a small scale. Another object of the present invention is to provide a drive detection circuit having a small scale and a small error when the drive detection circuit includes a drive circuit and a control circuit in the signal detection circuit.

One aspect of the present disclosure for solving the above problems is a signal detection circuit for a sensor array that detects an external stimulus of a sensor unit corresponding to an intersection of a matrix of a plurality of scanning wirings and a plurality of signal wirings. a is a plurality of signal lines are divided into M ₂ blocks one by _one M, in each of the M ₂ blocks are first the signal lines of _one M is connected to the input A second switching circuit is provided, and a load resistance and voltage detection amplifier connected to the output of the first switching circuit are provided, _{and each output from the M 2} blocks is connected to an input. It is a signal detection circuit having a switching circuit and an AD converter connected to the output of the second switching circuit.

Further, another aspect of the present disclosure is provided corresponding to each of a plurality of signal wirings, a plurality of scanning wirings intersecting the signal wirings, and intersections of the signal wirings and the scanning wirings, and the pixel electrodes and the first thin film transistor. A pixel electrode including a plurality of pixel portions including a second thin film transistor, a drain wiring for supplying power to the drain electrode of the first thin film transistor, a sensor portion connected to the pixel electrode, and a common electrode connected to the sensor portion. Is connected to the gate electrode of the first thin film transistor, the drain electrode of the first thin film transistor is connected to the drain wiring, the source electrode of the first thin film transistor is connected to the drain electrode of the second thin film transistor, and the gate electrode of the second thin film transistor is the scanning wiring. The source electrode of the second thin film transistor is a sensor array connected to the signal wiring.

Another aspect of the present disclosure is a sensor system comprising a sensor array and a signal detection circuit, wherein the sensor array includes a plurality of signal wirings, a plurality of scanning wirings intersecting the signal wirings, and a signal wiring. A plurality of pixel portions including a pixel electrode, a first thin film, and a second thin film, a drain wiring for supplying power to the drain electrode of the first thin film, and a pixel electrode, which are provided corresponding to each of the intersections of the scanning wiring and the scanning wiring. A sensor unit to be connected and a common electrode connected to the sensor unit are provided, the pixel electrode is connected to the gate electrode of the first thin film, the drain electrode of the first thin film is connected to the drain wiring, and the source of the first thin film is connected. The electrode is connected to the drain electrode of the second thin film, the gate electrode of the second thin film is connected to the scanning wiring, the source electrode of the second thin film is connected to the signal wiring, and the signal detection circuit has a plurality of signal wirings. It is divided into M2 blocks by M1 each, and in each of the M2 blocks, the first switching circuit to which the M1 signal wiring is connected to the input and the output of the first switching circuit A second switching circuit is provided with a connected load resistance and voltage detection amplifier, and each output from the M2 blocks is connected to the input, and an AD converter connected to the output of the second switching circuit. It is a sensor system having and.

According to the present disclosure, it is possible to provide a signal detection circuit on a small scale. Further, when the drive detection circuit includes the drive circuit and the control circuit in the signal detection circuit, it is possible to provide a drive detection circuit having a small scale and a small error.

FIG. 1 is a circuit diagram illustrating an exemplary signal detection circuit according to the first embodiment of the present disclosure. FIG. 2 is a circuit diagram illustrating an exemplary drive detection circuit including the signal detection circuit of FIG. FIG. 3 is a circuit diagram showing another example of the drive detection circuit including the signal detection circuit of FIG. FIG. 4 is an explanatory diagram showing a simple signal detection method. FIG. 5 is an explanatory diagram schematically showing the signal detection method of the present disclosure. FIG. 6 is a circuit diagram schematically showing a sensor array applied to the first embodiment. FIG. 7 is an explanatory diagram illustrating an exemplary signal detection circuit according to the second embodiment of the present disclosure. FIG. 8 is an explanatory diagram illustrating an exemplary drive detection circuit including the signal detection circuit of FIG. 7. FIG. 9 is an explanatory diagram schematically showing the signal detection method of the present disclosure. FIG. 10 is a circuit diagram schematically showing a sensor array applied to the second embodiment. FIG. 11 is an explanatory diagram showing an example of a pixel circuit according to the third embodiment of the present disclosure. FIG. 12 is a plan view and a cross-sectional view showing a specific example of the pixel circuit of FIG. FIG. 13 is an explanatory diagram showing an example of a pixel circuit according to the fourth embodiment of the present disclosure. 14 is a plan view and a cross-sectional view showing a specific example of the pixel circuit of FIG. 13. FIG. 15 is an explanatory diagram showing an example of a pixel circuit according to a fifth embodiment of the present disclosure. 16 is a plan view and a cross-sectional view showing a specific example of the pixel circuit of FIG. FIG. 17 is an explanatory diagram showing an example of a pixel circuit according to a sixth embodiment of the present disclosure. FIG. 18 is a plan view and a cross-sectional view showing a specific example of the pixel circuit of FIG. FIG. 19 is a block diagram schematically showing the nursing care data collection / determination system of the present disclosure. FIG. 20 is an explanatory diagram showing an arrangement example of the nursing care sensor device of the present disclosure. FIG. 21 is a circuit diagram schematically showing a sensor array applied to the first embodiment. FIG. 22 is a circuit diagram schematically showing a current limiting circuit applied to the seventh embodiment. FIG. 23 is an explanatory diagram including an example of a detection circuit connected to the pixel circuit of FIG. FIG. 24 is an explanatory diagram including another example of the detection circuit connected to the pixel circuit of FIG. FIG. 25 is an explanatory diagram including an example of a detection circuit connected to the pixel circuit of FIG. FIG. 26 is an explanatory diagram including another example of the detection circuit connected to the pixel circuit of FIG. FIG. 27 is an explanatory diagram showing an example of a conventional pixel circuit. FIG. 28 is an explanatory diagram showing another example of the conventional pixel circuit. FIG. 29 is a circuit diagram illustrating a conventional signal detection circuit as an example. FIG. 30 is a circuit diagram showing another example of a conventional signal detection circuit. FIG. 31 is a circuit diagram illustrating a conventional drive detection circuit as an example.

The embodiments of the present disclosure will be described in detail below with reference to the drawings. In the drawings used below, the scale is not drawn accurately for the sake of clarity. Also, the embodiments of the present disclosure are a group of embodiments based on a single invention of its own. In addition, each aspect of the present disclosure is an aspect of a group of embodiments based on a single invention. Each configuration of the present disclosure may have each aspect of the present disclosure. Each feature of the present disclosure can be combined to form each configuration. Therefore, each feature of the present disclosure, each configuration of the present disclosure, each aspect of the present disclosure, and each embodiment of the present disclosure can be combined, and the combination exerts a cooperative function and exerts a synergistic effect. Can be done.

[First Embodiment]
FIG. 1 shows a circuit diagram showing an example of a signal detection circuit according to the first embodiment of the present disclosure. The target sensor array to which this signal detection circuit is applied has M signal wirings 15. In Figure 1, M of signal lines 15 are divided into one by _one M M ₂ blocks (broken line in the portion surrounded by the Figure 1). When the signal wiring 15 of each block _{is referred to as signal wiring A to M 1} , in the signal detection circuit of the present embodiment, the signal wiring A to M ₁ is connected to the input of the first switching circuit 101, and the first switching circuit _{It has two} blocks in which the output of 101 is connected to the load resistor 20 and the voltage detection amplifier 53. The presence of the first switching circuit 101, the number of required load resistor 20 and the voltage detecting amplifier 53 is not the M becomes a _two M, can be reduced than the number of signal wires 15.

Further, the output of the voltage detection amplifier 53 of each block is connected to the input of the second switching circuit 102, and the output of the second switching circuit 102 is connected to the input of the AD converter 25. When the number of inputs of one second switching circuit 102 is L, the number of AD converters 25 need not the _two M, becomes (M 2 _{/ L)} number, can be reduced than the number of the voltage detection amplifier 53 .. When the number of inputs L of the second switching circuit 102 _{is equal to M 2} , the number of AD converters 25 required is one.

In this way, by combining the first switching circuit 101 and the second switching circuit 102, the number of load resistance 20 and the voltage detection amplifier 53 can be reduced from the number of signal wirings 15, and the number of AD converters 25 can be detected by voltage. Since the number can be reduced from the number of amplifiers 53, the scale of the signal detection circuit can be reduced, and the installation area and manufacturing cost can be suppressed.

Although the voltage detection amplifier 53 is described as a voltage follower in FIG. 1, the present invention is not limited to this, and a circuit having an amplification factor other than 1 or an inverting amplifier circuit may be used. Further, the voltage detection amplifier 53 may have a known oscillation prevention circuit, phase compensation circuit, capacitance correction circuit, and protection circuit. Further, a FET (Field Effect Transistor) or the like may be used instead of using an operational amplifier. Further, in FIG. 1, it is described that the load resistor 20 is installed between the signal line and the GND, but when the voltage detection amplifier 53 is an inverting amplifier circuit, it is between the signal line and the output of the voltage detection amplifier 53. It may be installed in.

Further, it is desirable that the first switching circuit 101 is an analog multiplexer. If an analog multiplexer is used, switching can be performed at high speed without losing the information of the analog signal. However, if the signal voltage range is too large for the analog multiplexer to handle, a relay may be used.

Since the load resistance 20 is not on the input side but on the output side of the first switching circuit 101, a current flows through the first switching circuit 101 to lower the impedance, and the circuit is less susceptible to noise. Further, since the current flows only in the signal line of the input switched to the output of the first switching circuit 101 among the signal wiring 15 connected to the first switching circuit 101, the power consumption can be suppressed.

Next, FIG. 2 shows a circuit diagram showing an example of a drive detection circuit including the signal detection circuit of FIG. The sensor array to which this drive detection circuit is applied has M signal wirings 15 and N scanning wirings 12. The drive detection circuit of FIG. 2 includes a control circuit 5 and a drive circuit 6 in addition to the signal detection circuit according to the present embodiment, and includes a first switching circuit 101, a second switching circuit 102, and an AD. The converter 25 and the drive circuit 6 are controlled by the control circuit 5. In order to control the first switching circuit 101, digital wiring 48 having the number of bits n (where 2 ^n-1 <M ₁ ≤ 2 ⁿ _{) that can switch the switching circuit having the number of inputs M 1 is required.} The number of digital wiring 48 required in the block is _{2 if M 1} = 4, 3 if _{M 1} = 8, and 4 if _{M 1} = 16.

When the number of digital outputs of the control circuit 5 is small, it is preferable to control the first switching circuit 101 by using the counter 49 as shown in FIG. As a result, the digital wiring 48 for switching the input of each block can be made one by one.

FIG. 4 shows an easily conceivable signal detection method when the drive detection circuit of FIGS. 2 and 3 is applied. In FIG. 4, the second switching circuit 102 is switched to the block 1 in advance. After applying the on-voltage to the first line of the scanning wiring 12, the first switching circuit 101 of the block 1 is set to the signal A, and the data of the signal A is read by the AD converter 25. Next, the first switching circuit 101 is set to signal B, and the data of signal B is read by the AD converter 25. Similarly, after reading the data up to the signal M ₁ in order by the AD converter 25, the second switching circuit 102 is switched to the block 2, and the signals A to M 1 of the block 2 are read in order in the same _{manner as the block 1.} .. Then, in the same manner as in

blocks

1 and 2, read until the block _{M 2.} In this case, the data can be read in the order of pixel arrangement, which is easy to understand, but has the following problems.

Since the data is read by the AD converter 25 immediately after switching the first switching circuit 101, the data is read before the signal is stable, and the error becomes large.

The improved signal detection method will be described with reference to FIG. In FIG. 5, all the first switching circuits 101 are switched to the signal A in advance. After applying the on-voltage to the first line of the scanning wiring 12, wait for a certain period of time.

After that, the second switching circuit 102 is switched to the block 1, the data of the signal A of the block 1 is read by the AD converter 25, and then the first switching circuit 101 of the block 1 is set to the signal B. Next, the second switching circuit 102 is switched to the block 2, the data of the signal A of the block 2 is read by the AD converter 25, and then the first switching circuit 101 of the block 2 is set to the signal B. Hereinafter, block 3, block 4, also performed on ..., also applies to the block _{M 2,} i.e., by switching the second switching circuit 102 to the block _{M 2,} the data signal A of the block _{M 2} AD After being read by the converter 25, the first switching circuit 101 of the _{block M 2 is set to the signal B.} (The above is the "signal A reading / switching to signal B process")

After that, the second switching circuit 102 is switched to the block 1, the data of the signal B of the block 1 is read by the AD converter 25, and then the first switching circuit 101 of the block 1 is set to the signal C. Next, the second switching circuit 102 is switched to the block 2, the data of the signal B of the block 2 is read by the AD converter 25, and then the first switching circuit 101 of the block 2 is set to the signal C. Hereinafter, block 3, block 4, also performed on ..., also applies to the block _{M 2,} i.e., by switching the second switching circuit 102 to the block _{M 2,} AD converter data signal B block M2 After reading at 25, the first switching circuit 101 of the _{block M 2 is set to the signal C.} (The above is the "signal B reading / switching to signal C process")

After that, in the same manner as the "signal A reading / switching to signal B" and "signal B reading / switching to signal C", "signal C reading / switching to signal D" and "signal D reading / switching to signal E". switching step ", ... and continued, to switch process" to "signal M ₁ read-signal a, i.e., by switching the second switching circuit 102 to block 1, the data of the signal M ₁ of the block 1 AD After being read by the converter 25, the first switching circuit 101 of the block 1 is set to the signal A. Next, the second switching circuit 102 is switched to the block 2, _{the data of the signal M 1} of the block 2 is read by the AD converter 25, and then the first switching circuit 101 of the block 2 is set to the signal A. Hereinafter, block 3, block 4, do the same for., Same for block _{M 2,} i.e., by switching the second switching circuit 102 to the block _{M 2,} the data of the signal _{M 1} of the block _{M 2} after reading the AD converter 25, the first switching circuit 101 of the block _{M 2} to the signal a. However, this description is specifically described for the sake of clarity _{, and does not limit the signal M 1 to} be later than the signal E, that is, does not limit it to M ₁ > 5. ₁ may be an integer of 2 or more. Further, the block M ₂ is not limited to being later than the block 4, that is, it is not limited to M ₂ > 4, and M ₂ may be an integer of 2 or more.

Subsequently, an off voltage is applied to the first line of the scanning wiring 12, and then an on voltage is applied to the second line of the scanning wiring 12, and the process waits for a “fixed time”. As in the case of the first row of the scanning lines 12, performs "signal A read-signal B to the switching process" - "signal M ₁ read-signal A to the switching process."

The same operation is performed up to the Nth line of the scanning wiring 12, and the off voltage is applied to the Nth line of the scanning wiring 12. Up to this point, sensor information for one screen can be obtained. Further, by repeating the same operation, data for a plurality of screens, that is, time-dependent data of signals of all pixels can be obtained. (However, it is not limited to N> 2, and N may be an integer of 1 or more.)

More generally, the characteristics of the signal detection method of FIG. 5 will be shown. After switching the signal wiring selected by the first switching circuit 101 to another different signal wiring, before measuring the signal, The measurement of the signal of the signal wiring selected by the first switching circuit of the other block is performed one or more times. As a result, it is possible to gain time from switching the first switching circuit 101 until the signal stabilizes, and it is possible to improve the accuracy of signal measurement. Especially when the number of blocks is _two M, the switching of the first signal switching circuit 101, between the measurement of the switching signal, the other (M 2 _-1) measurements easily be performed can.

In addition, the features of the signal detection method of FIG. 5 will be shown a little more concretely. The control circuit 5 performs a first process of causing the drive circuit 6 to apply an on-voltage to one scanning wiring selected from the plurality of scanning wirings 12. After applying the on-voltage, wait for a certain period of time. Then, in one block selected by the second switching circuit, the signal of one signal wiring selected by the first switching circuit is read out via the AD converter 25, and one by the first switching circuit 101. A procedure for selecting another block different from one block by the second switching circuit 102 after selecting another signal line different from the signal wiring and before reading the signal of the selected other signal wiring 15. , A procedure for reading a signal, a procedure for switching the first switching circuit 101 of another block, and a procedure for selecting one block by the second switching circuit 102, which are selected by these processes. A second process is performed in which the signals of the sensor unit for one line corresponding to the one scanning wiring 12 are read out in order. Further, the drive circuit 6 is subjected to a third process of applying an off voltage to one scanning wiring 12 selected after the completion of the second process. The signals of all the sensor units are read out by repeating the first process, the standby, the second process, and the third process for all the scanning wirings 12.

However, in one block, the procedure of selecting another signal line different from one signal wiring 15 by the first switching circuit 101 and the selection of another block different from one block by the second switching circuit 102. The procedure may be reversed. That is, the second process is performed after reading the signal of one signal wiring 15 selected by the first switching circuit 101 in one block selected by the second switching circuit 102 via the AD converter 25. After selecting another block different from one block by the second switching circuit 102 and selecting another signal line different from one signal wiring 15 for the first switching circuit 101 of one block, 1 Before reading the signal of the other signal wiring 15 of one block, the procedure of reading the signal of the other block, the procedure of switching the second switching circuit 102, and the procedure of switching the first switching circuit 101 of the other block. , And, by these processes, the signal of one line of the sensor unit corresponding to one selected scanning wiring 12 may be read out in order.

Therefore, in the second process, after selecting another signal wiring 15 different from one signal wiring 15 by the first switching circuit 101 of one block, and before reading the signal of the other signal wiring 15 of one block. At least, the procedure of reading the signal of the other block, the procedure of switching the second switching circuit 102, and the procedure of switching the first switching circuit 101 of the other block are repeated.

Further, waits a predetermined time from the turn-on voltage is applied to the one of the N of scanning lines 12, the "predetermined time" is the measurement time of the AD converter 25 (M 2 _-1) times or more. Then, regarding the signal A of the block 1, which is the first measurement of one screen, the measurement of the AD converter 25 is performed after the first switching circuit 101 is switched to the signal A and before the measurement of the signal A is performed. to be able to sandwich the time × (M 2 _-1) or more, the signal as with the measurement of other signals can earn time to stabilize, improve the accuracy of signal measurement to the same extent as the other signal be able to.

An example of a sensor array suitable for the signal detection circuit, the drive detection circuit, and the signal detection method of the present embodiment will be described. FIG. 6 is a circuit diagram showing an example of a sensor array applied to the first embodiment. In the sensor array, a pixel circuit consisting of the first thin film transistor T1 and the second thin film transistor T2 is assembled at the intersection of the matrix of N scanning wires 12 and M signal wirings 15, and the gate of the first thin film transistor T1 is formed. A pressure-sensitive medium 9, for example, is provided as a sensor unit 109 between the electrode and the common electrode 10. The drain wiring 14 is connected to the drain of the first thin film transistor T1, the source of the first thin film transistor T1 is connected to the drain of the second thin film transistor T2, and the gate of the second thin film transistor T2 is connected to the scanning wiring 12. The source of the second thin film transistor T2 is connected to the signal wiring 15. A pressure-dependent voltage is generated in the pressure-sensitive medium 9. When one of the scanning wires 12 is turned on, a current depending on the stimulation (pressure, etc.) of the pixels in that row flows through the signal wiring 15. As the sensor unit 109, a pressure sensitive medium 9, for example, polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-trifluoroethylene copolymer is suitable. Note that FIG. 6 is an example, and the present invention is not limited to the sensor array having this structure. FIG. 21 is a circuit diagram showing an example of a sensor array applied to the first embodiment. In the sensor array, a pixel circuit by the thin film transistor 38 is assembled at the intersection of the matrix of N scanning wires 12 and M signal wires 15, and the pressure is sensitive between the drain electrode of the thin film transistor 38 and the power supply wiring 36. It has a medium 39. The gate of the thin film transistor 38 is connected to the scanning wire 12, and the source of the thin film transistor 38 is connected to the signal wire 15. The resistance value of the pressure sensitive medium 39 changes depending on the pressure. When one of the scanning wires 12 is turned on, a current that depends on the pressure of the pixels in that row flows through the signal wires 15. As the pressure sensitive medium 39, rubber or the like in which conductive particles are dispersed is suitable. Alternatively, another sensor unit 109 may be adopted and used for another type of pressure sensor, displacement sensor, temperature sensor, or the like. Further, the power supply wiring 36 may have a current limiting circuit 40 described later in the seventh embodiment.

As described above, in the signal detection circuit according to the first embodiment, the number of the load resistance 20 and the voltage detection amplifier 53 is increased by providing the first switching circuit 101 on the upstream side of the load resistance 20 and the voltage detection amplifier 53. Further, by providing the second switching circuit 102 on the downstream side of the voltage detection amplifier 53, the number of AD converters 25 can be reduced, and the scale of the signal detection circuit can be reduced. Further, by applying the signal detection circuit, the scale of the drive detection circuit can be reduced. Further, after the signal is switched by the first switching circuit 101 and before the measurement of the signal is performed, the switched and unmeasured signals of other blocks are measured, so that the measurement is performed after the switching signal becomes stable. It can be performed.

[Second Embodiment]
A second embodiment of the present disclosure will be described with reference to FIG. 7. FIG. 7 is an explanatory diagram showing an example of the signal detection circuit according to the second embodiment of the present disclosure. The sensor array to which this signal detection circuit is applied has M signal wirings 15 and M reference signal wirings 16. Signal lines 15 and the reference signal lines 16 are divided into _{M 2} blocks one by _one each _M. The signal wirings A to M ₁ of each block are connected to the input of the first switching circuit 101, and the output of the first switching circuit 101 is connected to the load resistance 20 and the voltage detection amplifier 53. Further, the reference signal wirings A to M ₁ of each block are connected to the input of the third switching circuit 103, and the output of the third switching circuit 103 is connected to the load resistance 21 and the voltage detection amplifier 54. Therefore, the required load resistance and the number of voltage detection amplifiers are not the total of the signal wiring 15 and the reference signal wiring 16 (M × 2), but twice the number of blocks (M ₂ × 2).

Further, the output of the voltage detection amplifier 53 of the signal and the output of the voltage detection amplifier 54 of the reference signal corresponding to the signal are input to the differential amplifier circuit 24. The number of differential amplifier circuits 24 required is M ₂ , which is the same as the number of blocks. The output of the differential amplifier circuit 24 is connected to the input of the second switching circuit 102, and the output of the second switching circuit 102 is connected to the input of the AD converter 25. When the number of inputs of the second switching circuit 102 is L, the number of AD converters 25 need not the _two M, becomes (M 2 _{/ L)} number, it can be reduced than the number of the differential amplifier circuit 24. When the number of inputs L of the second switching circuit 102 _{is equal to M 2} , the number of AD converters 25 required is one.

In this way, by combining the first switching circuit 101, the third switching circuit 103, and the second switching circuit 102, the number of the load resistance 20 and the voltage detection amplifier 53 can be reduced from the number of the signal wiring 15. Since the number of load resistors 21 and voltage detection amplifiers 54 can be reduced from the number of reference signal wirings 16 and the number of AD converters 25 can be reduced from the number of differential amplifier circuits 24, the scale of the signal detection circuits can be reduced and installed. Area and cost can be reduced.

Although the

voltage detection amplifiers

53 and 54 are described as voltage followers in FIG. 7, the present invention is not limited to this, and a circuit having an amplification factor other than 1 or an inverting amplifier circuit may be used. Further, the

voltage detection amplifiers

53 and 54 may have known oscillation prevention circuits, phase compensation circuits, capacitance correction circuits, and protection circuits. Further, FET or the like may be used instead of the operational amplifier. Further, in FIG. 7, it is described that the

load resistors

20 and 21 are installed between the signal line and the GND, but when the

voltage detection amplifiers

53 and 54 are inverting amplifier circuits, the output of the signal line and the inverting amplifier circuit It may be installed between. Further, the differential amplifier circuit 24 may be a circuit in which the amplification factor is 1 and the difference between the signal and the reference signal is observed, but the amplification factor may be other than 1. Further, the differential amplifier circuit 24 can shift the output voltage by the base voltage Vbase. In the differential amplifier circuit 24, by adding Vbase to the signal wiring output-reference output, even when the signal wiring output-reference output is small or negative, it can be reliably detected.

Further, it is desirable that the first switching circuit 101 and the third switching circuit 103 are analog multiplexers. With an analog multiplexer, switching is possible at high speed without losing the information of the analog signal. However, if the signal voltage range is too large for the analog multiplexer to handle, a relay may be used.

Due to the

load resistors

20 and 21 on the output side of the first switching circuit 101 and the third switching circuit 103 instead of the input side, a current flows through the first switching circuit 101 and the third switching circuit 103. The impedance becomes low, and the circuit is less susceptible to noise. Further, of the signal wiring 15 connected to the first switching circuit 101, only the input signal line switched to the output of the first switching circuit 101 and the reference signal wiring 16 connected to the third switching circuit 103. Since the current flows only through the reference signal line of the input switched to the output of the third switching circuit 103, the power consumption can be suppressed.

Next, the drive detection circuit according to this embodiment will be described. FIG. 8 is an explanatory diagram showing an example of a drive detection circuit including the signal detection circuit of FIG. The sensor array to which this drive detection circuit is applied has M signal wirings 15, M reference signal wirings 16, and N scanning wirings 12. The drive detection circuit of FIG. 8 includes a control circuit 5 and a drive circuit 6 in addition to the signal detection circuit according to the present embodiment, and includes a first switching circuit 101, a third switching circuit 103, and a third switching circuit 103. The switching circuit 102 of 2, the AD converter 25, and the drive circuit 6 are controlled by the control circuit 5. When the number of digital outputs of the control circuit 5 is small, the counter 49 is used to control the first switching circuit 101 and the third switching circuit 103. If the counter 49 is used, the digital wiring 48 for switching the input of each block can be made one by one.

Even when the drive detection circuit shown in FIG. 8 is applied, the signal detection method shown in FIG. 9 is desirable instead of the simple signal detection method as in the first embodiment.

In FIG. 9, all the first switching circuits 101 are switched to the signal A, the third switching circuit 103 is switched to the reference signal A, and the second switching circuit 102 is switched to the block 1. After applying the on-voltage to the first line of the scanning wiring 12, wait for a "fixed time".

After that, the data corresponding to the difference between the signal A of the block 1 and the reference signal A is read by the AD converter 25, and then the first switching circuit 101 of the block 1 is used as the signal B and the third switching circuit 103 of the block 1 is used. Set to reference signal B. Next, the second switching circuit 102 is switched to the block 2, the data corresponding to the difference between the signal A and the reference signal A of the block 2 is read by the AD converter 25, and then the first switching circuit 101 of the block 2 is used. For the signal B, the third switching circuit 103 of the block 2 is used as the reference signal B. Hereinafter, the same applies to the blocks 3, the blocks 4, ..., And the same applies to the block M ₂ , that is, the second switching circuit 102 is switched to the block M ₂ , and the signal A and the reference signal A of the _{block M 2 are switched.} data corresponding to the difference from the loading by the AD converter 25, a first switching circuit 101 of the block _{M 2} to the signal B, and the third switching circuit 103 of the block _{M 2} in the reference signal B. (The above is the "signal difference A reading / switching to signal B process")

After that, the second switching circuit 102 is switched to the block 1, the data corresponding to the difference between the signal B and the reference signal B of the block 1 is read by the AD converter 25, and then the first switching circuit 101 of the block 1 is signaled. In C, the third switching circuit 103 of the block 1 is used as the reference signal C. Next, the second switching circuit 102 is switched to the block 2, the data corresponding to the difference between the signal B and the reference signal B of the block 2 is read by the AD converter 25, and then the first switching circuit 101 of the block 2 is used. For the signal C, the third switching circuit 103 of the block 2 is used as the reference signal C. Hereinafter, the same applies to the blocks 3, the blocks 4, ..., And the same applies to the block M ₂ , that is, the second switching circuit 102 is switched to the block M ₂ , and the signal B and the reference signal B of the _{block M 2 are switched.} data corresponding to the difference from the loading by the AD converter 25, a first switching circuit 101 of the block _{M 2} to the signal C, and a third switching circuit 103 of the block _{M 2} in the reference signal C. (The above is the "signal difference B reading / switching to signal C process")

After that, "Signal difference A reading / switching to signal B", "Signal difference B reading / switching to signal C"
In the same manner as above, "Signal difference C reading / switching to signal D", "Signal difference D reading / switching to signal E", and so on, followed by "Signal difference M1 reading / switching to signal A". That is, the second switching circuit 102 is switched to the block 1, _{the data corresponding to the difference between the signal M 1} _{of the block 1} and the reference signal M 1 is read by the AD converter 25, and then the first switching of the block 1 is performed. The circuit 101 is used as the signal A, and the third switching circuit 103 of the block 1 is used as the reference signal A. Then, by switching the second switching circuit 102 to the block 2, the data corresponding to the difference between the signal M ₁ and the reference signal M ₁ of the block 2 from the loading by the AD converter 25, a first switching circuit block 2 101 is used as the signal A, and the third switching circuit 103 of the block 2 is used as the reference signal A. Hereinafter, the same applies to the blocks 3, the blocks 4, ..., And the same applies to the block M ₂ , that is, the second switching circuit 102 is switched to the block M ₂ , and the signal M ₁ and the reference signal of the _{block M 2 are switched.} data corresponding to the difference between M ₁ after reading the AD converter 25, a first switching circuit 101 of the block _{M 2} to the signal a, the third switching circuit 103 of the block _{M 2} in the reference signal a. However, this description is specifically described for the sake of clarity _{, and does not limit the signal M 1 to} be later than the signal E, that is, does not limit it to M ₁ > 5. ₁ may be an integer of 2 or more. Further, the block M ₂ is not limited to being later than the block 4, that is, it is not limited to M ₂ > 4, and M ₂ may be an integer of 2 or more.

Subsequently, an off voltage is applied to the first line of the scanning wiring 12, and then an on voltage is applied to the second line of the scanning wiring 12, and the process waits for a “fixed time”. Similar to the first line of the scanning wiring 12, "signal difference A reading / switching to signal B" to "signal difference M ₁ reading / switching to signal A" are performed.

The same operation is performed up to the Nth line of the scanning wiring 12, and the off voltage is applied to the Nth line of the scanning wiring 12. Up to this point, sensor information for one screen can be obtained. Further, by repeating the same operation, data for a plurality of screens, that is, time-dependent data of signal differences of all pixels can be obtained. (However, it is not limited to N> 2, and N may be an integer of 1 or more.)

The feature of the signal detection method of FIG. 9 is that after switching to the signal wiring selected by the first switching circuit 101 and the reference signal corresponding to the signal wiring, before measuring the signal difference between them, the other The measurement of the difference between the signal of the signal wiring selected by the first switching circuit 101 of the block and the signal of the reference signal wiring corresponding to the signal wiring is performed one or more times. As a result, it is possible to gain time from switching the first switching circuit 101 and the third switching circuit 103 until the signal stabilizes, and it is possible to improve the accuracy of signal measurement. Especially when the number of blocks is _two M, it can be easily sandwich the measurements (M 2 _-1) times.

In addition, the features of the signal detection method of FIG. 9 will be shown a little more concretely. The control circuit 5 performs a first process of causing the drive circuit 6 to apply an on-voltage to one scanning wiring 12 selected from the plurality of scanning wirings 12. After applying the on-voltage, wait for a certain period of time. Then, in one block selected by the second switching circuit 102, one signal wiring 15 selected by the first switching circuit 101 and one signal wiring 15 selected by the third switching circuit 103. The signal difference of the reference signal wiring 16 corresponding to the above is read out via the AD converter 25, and one signal wiring 15 and another signal line different from the reference signal wiring 16 and the reference signal wiring 16 are read by the first and third switching circuits. After selecting, and before reading the signal difference of the other selected signal wiring 15 and the reference signal wiring 16, the procedure of selecting another block different from one block by the second switching circuit 102 and the signal difference. There is a procedure of reading out, a procedure of switching the first and third switching circuits of other blocks, and a procedure of selecting one block by the second switching circuit 102, and the selection is performed by these processes. A second process is performed in which the signal difference of one line of the sensor unit corresponding to the one scanning wiring 12 is read out in order. Further, the drive circuit 6 is subjected to a third process of applying an off voltage to one scanning wiring 12 selected after the completion of the second process. The signals of all the sensor units are read out by repeating the first process, the standby, the second process, and the third process for all the scanning wirings 12.

However, a procedure for selecting another signal wiring 15 and a reference signal wiring 16 different from one signal wiring 15 and the reference signal wiring 16 by the first and third switching circuits in one block, and a second switching circuit 102. The procedure for selecting another block that is different from one block may be reversed. That is, in the second process, in one block selected by the second switching circuit 102, the signal difference between the one signal wiring 15 and the reference signal wiring 16 selected by the first and third switching circuits is AD. After reading through the converter 25, another block different from one block is selected by the second switching circuit 102, and the first and third switching circuits of one block are connected to one signal wiring 15 and a reference signal. After selecting another signal wiring 15 and reference signal wiring 16 different from the wiring 16, read the signal difference of the other block before reading the signal difference of the other signal wiring 15 and the reference signal wiring 16 of one block. It has a repetition of a procedure, a procedure for switching the second switching circuit 102, and a procedure for switching the first and third switching circuits of other blocks, and one scanning wiring selected by these processes. The signals of one line of the sensor unit corresponding to 12 may be read out in order.

Therefore, in the second process, the first switching circuit 101 and the third switching circuit 103 of one block select the other signal wiring 15 and the reference wiring 16 different from the one signal wiring 15 and the reference signal wiring 16. After that, before reading the signal difference of the other signal wiring 15 and the reference signal wiring 16 of one block, at least the procedure of reading the signal difference of the other block, the procedure of switching the second switching circuit 102, and other procedures. The procedure for switching the first switching circuit 101 and the third switching circuit 103 of the block is repeated.

Further, waits a predetermined time from the turn-on voltage is applied to the one of the N of scanning lines 12, the "predetermined time" is the measurement time of the AD converter 25 (M 2 _-1) times or more. Then, regarding the difference between the signal A and the reference signal A of the block 1, which is the first measurement on one screen, the signal after switching the first switching circuit 101 and the third switching circuit 103 to the signal A by performing the measurement of the difference between a and the reference signal a, to be able to sandwich the measuring time × (M 2 _-1) or more AD converters 25, is measured as well as signal and reference signals of the other signal difference It is possible to gain time until it stabilizes, and the accuracy of signal measurement can be improved to the same level as other signal differences. Further, since the measurement is performed after the signal and the reference signal are stable, the time constant until the signal stabilizes and the time constant until the reference signal stabilizes do not necessarily have to match.

A suitable sensor array applicable to the signal detection circuit, drive detection circuit, and signal detection method of the present embodiment will be described. FIG. 10 is a circuit diagram showing an example of a sensor array applied to the second embodiment. In the sensor array, a pixel circuit consisting of the first thin film transistor T1 and the second thin film transistor T2 is assembled at the intersection of the matrix of N scanning wires 12 and M signal wirings 15, and the gate of the first thin film transistor T1 is formed. A pressure-sensitive medium 9, for example, is provided as a sensor unit 109 between the electrode and the common electrode 10. Further, a reference circuit by a third thin film transistor T3 and a fourth thin film transistor T4 is assembled at the intersection of N scanning wires 12 and M reference signal wirings 16, and the third thin film transistor T3 becomes the first thin film transistor T1. Adjacent. The channel length / channel width of the third thin film transistor T3 is equal to the channel length / channel width of the first thin film transistor T1, and the channel length / channel width of the fourth thin film transistor T4 is the channel length / channel of the second thin film transistor T2. Ideally equal to width. The drain wiring 14 is connected to the drain of the first thin film transistor T1, the source of the first thin film transistor T1 is connected to the drain of the second thin film transistor T2, and the gate of the second thin film transistor T2 is connected to the scanning wiring 12. The source of the second thin film transistor T2 is connected to the signal wiring 15. A voltage that depends on the stimulus (pressure, etc.) is generated in the sensor unit 109. On the other hand, the common electrode 10 is connected to the gate of the third thin film transistor T3, the drain wiring 14 is connected to the drain of the third thin film transistor T3, and the source of the third thin film transistor T3 is the drain of the fourth thin film transistor T4. Connected, the gate of the fourth thin film transistor T4 is connected to the scanning wire 12, and the source of the fourth thin film transistor T4 is connected to the reference signal wire 16. When one of the scanning wires 12 is turned on, a current that depends on the pressure of the pixels in that row flows through the signal wiring 15, and a current that has characteristics similar to those of the pixel circuit in that row and does not depend on stimuli (pressure, etc.). Flows through the reference signal wiring 16. As the sensor unit 109, a pressure sensitive medium 9, for example, polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-trifluoroethylene copolymer is suitable. The sensor array applicable to this embodiment is not limited to the sensor array having the structure shown in FIG. For example, a pressure-sensitive medium whose resistance changes depending on the pressure may be used, and a signal of an element to which pressure is applied and a reference signal of an element to which pressure is not applied may be used. Alternatively, another sensor unit 109 may be adopted and used for another type of pressure sensor, displacement sensor, temperature sensor, or the like. Further, the drain wiring 14 may have a current limiting circuit 40 described later in the seventh embodiment.

By subtracting the detection voltage from the adjacent reference signal wiring 16 from the detection voltage from the signal wiring 15, the in-plane distribution of the thin film transistor array can be canceled because the characteristics of the adjacent thin film transistors are similar. Further, since the temperatures of the adjacent thin film transistors are the same, most of the temperature dependence of the thin film transistors can be canceled.

As described above, in the signal detection circuit according to the second embodiment, the first switching circuit 101 is located upstream of the load resistance 20 and the voltage detection amplifier 53, and the first switching circuit 101 is located upstream of the load resistance 21 and the voltage detection amplifier 54. By providing the switching circuit 103 of 3, the number of

load resistors

20 and 21 and the

voltage detection amplifiers

53 and 54 can be reduced, and further, a second switching circuit 102 is provided on the downstream side of the differential amplifier circuit 24. Therefore, the number of AD converters 25 can be reduced, and the scale of the signal detection circuit can be reduced. Further, by applying the signal detection circuit, the scale of the drive detection circuit can be reduced. Further, after the signals are switched by the first switching circuit 101 and the third switching circuit 103, the switched and unmeasured signal differences of other blocks are measured before the signal difference is measured. , The measurement can be performed after the switching signal becomes stable, and a signal detection method with a small error can be provided.

In the conventional sensor array, there is a problem that the pressure-sensitive medium whose resistance changes tends to deteriorate. Therefore, it has been studied to use a pressure-sensitive medium of a type in which the potential difference changes as in Patent Document 2 (FIG. 28). However, there is a problem that a circuit having a load resistance in a pixel and reading a potential as in Patent Document 2 is vulnerable to noise. Further, since the first thin film transistor 41 is used as the grounded-source circuit, there is a problem that it is easily affected by the mobility of the thin film transistor and the variation of the threshold value. Further, the pressure-sensitive medium of Patent Document 2 is an inorganic substance, and has a problem of being vulnerable to mechanical impact.

Therefore, a sensor array that is less affected by variations in the mobility of the thin film transistor and the threshold value and is resistant to noise will be described in the third to sixth embodiments.

[Third Embodiment]
An example of a conventional pixel circuit is shown in FIG. In FIG. 27, the pressure-sensitive medium 130, which is a sensor unit, is of a type in which the resistance changes depending on the pressure, and one end is connected to the common electrode and the other end is connected to the drain electrode of the thin film transistor 31. A power supply is connected to the common electrode. A gate voltage (on voltage) that turns on the thin film transistor 31 is applied to one of the scanning wires 32, and a gate voltage (off voltage) that turns off the thin film transistor 31 is applied to the other scanning wires 32. A current flowing through the pressure-sensitive medium 130 of the corresponding pixel flows through the signal wiring 33 through the thin film transistor 31 belonging to the scanning wiring 32 to which the on-voltage is applied. By sequentially changing the scanning wiring 32 to be turned on one by one, the pressure data of all lines is read out.

FIG. 28 shows another example of the conventional pixel circuit. In FIG. 28, the pressure-sensitive medium 140, which is a sensor unit, is of a type in which the potential difference changes depending on the pressure. One end of the pressure sensitive medium 140 is connected to the gate electrode of the first thin film transistor 41, the other end is connected to the source electrode of the first thin film transistor 41, and the first thin film transistor 41 is connected to the power supply via the drain resistance 43 in the pixel. The first thin film transistor 41 is a source grounded circuit. A gate voltage (on voltage) that turns on the second thin film transistor 42 is applied to one of the scanning wires 44, and a gate voltage (off voltage) that turns off the second thin film transistor 42 is applied to the other scanning wires 44. Apply. Then, the drain voltage of the corresponding pixel is drawn out to the signal wiring 45 through the second thin film transistor 42 belonging to the scanning wiring 44 to which the on-voltage is applied. By sequentially changing the scanning wiring 44 to be turned on one by one, the pressure data of all lines can be read out.

However, since the circuit that reads out the voltage has a high input impedance, if the signal wiring 45 is long, noise is likely to be mixed in the signal. Further, if the impedance of the detection circuit is lowered so that noise is less likely to be mixed in this circuit, the drain resistor 43 flows through the detection circuit (not necessarily) in addition to the current flowing through the first thin film 41 (depending on the pressure). A current (which does not depend on the pressure) flows, and the voltage drop of the drain resistor 43 due to the current flowing through the detection circuit becomes an error. Further, since the source grounded circuit amplifies both the voltage and the current, the sensitivity is high, but the signal voltage is easily affected by the mobility and the variation of the threshold value of the first thin film transistor 41.

Therefore, the pixel circuit of the third embodiment of the present disclosure is shown in FIG. In FIG. 11, the sensor unit 109 (for example, the pressure sensitive medium 9) is of a type in which the potential difference changes depending on a stimulus (pressure or the like). One end of the sensor unit 109 is connected to the common electrode 10, the other end is connected to the gate electrode G1 of the first thin film transistor, and the drain electrode D1 of the first thin film transistor is connected to the power supply Vdd via the drain wiring 14, and the first The source electrode S1 of the thin film transistor is connected to the drain electrode D2 of the second thin film transistor, the gate electrode G2 of the second thin film transistor is connected to the scanning wiring 12, and the source electrode S2 of the second thin film transistor is connected to the signal wiring 15. Including the load resistance 20 in the signal detection circuit, the first thin film transistor is a drain ground circuit (source follower). A gate voltage (on voltage) that turns on the second thin film transistor is applied to one of the scanning wires 12, and a gate voltage (off voltage) that turns off the second thin film transistor is applied to the other scanning wires 12. .. Then, the source electrode S1 of the corresponding pixel is connected to the signal wiring 15 and connected to the load resistance 20 in the signal detection circuit through the second thin film transistor belonging to the scanning wiring 12 to which the on-voltage is applied. That is, since the load resistor 20 is outside the array, a current flows through the signal wiring 15, so that the impedance is low and noise is unlikely to be mixed into the signal. Further, since it is a drain ground (source follower) circuit, only the current is amplified and the source potential is close to the gate potential, so that the signal voltage is not easily affected by the variation in mobility of the first thin film transistor. The pressure data of each line can be read out by sequentially changing the scanning wiring 12 to be turned on one by one.

Since the potential of the common electrode 10 is added to the potential difference depending on the stimulation (pressure or the like) of the sensor unit 109 and applied to the gate electrode G1 of the first thin film, the operating point is determined by the potential of the common electrode 10. Can be adjusted.

As the sensor array detection method in the third embodiment, for example, the signal detection circuit, the drive detection circuit, and the signal detection method according to the first embodiment can be preferably used. At this time, the number of scanning wires 12 of the sensor array is N, and the number of signal wires 15 is M.

As the sensor unit 109, the pressure sensitive medium 9 (type in which the potential difference changes) is suitable. However, it is also possible to use another pressure-sensitive medium, a displacement-sensitive medium, a temperature-sensitive medium, or the like as the sensor unit 109.

When the potential of the drain wiring 14 is changed from 0 to Vdd immediately before the measurement, the capacitance between the gate and drain electrodes of the first thin film transistor (the pixel electrode 8 connected to the gate electrode G1 and the drain electrode D1 are connected). Assuming that (including the drain wiring 14) is Cgd1 and the capacitance between the pixel electrode 8 and the common electrode 10 is Cp, the potential of the pixel electrode 8 is shifted by ΔVp = Vdd × Cgd1 / (Cgd1 + Cp). This deviation needs to be sufficiently smaller than the maximum potential change amount of the sensor unit 109, and needs to be suppressed within 10% of the maximum potential change amount, for example. In order to suppress the above deviation within 10% of the maximum potential change amount, | Vdd × Cgd1 / (Cgd1 + Cp) | ≦ maximum potential change amount × 0.1 may be set. Here, the maximum potential change amount is the amount of change in the pixel electrode potential from the state in which no stimulus (pressure, etc.) is applied to the sensor to the time when the stimulus of the maximum value in the detection range set in the sensor is applied. be. For example, when the maximum potential change amount is 4 [V], | Vdd × Cgd1 / (Cgd1 + Cp) | ≦ 0.4.

A specific example of the sensor array shown in FIG. 11 is shown in FIG. It has gate electrodes G1 and G2 on the insulating substrate 1 (G2 is connected to the scanning wiring 12), has a gate insulating film 3 on it, has semiconductors SC1 and SC2 on it, and has semiconductors SC1 and SC2 on it. It has source electrodes S1 and S2 and drain electrodes D1 and D2 (S1 is connected to D2 via a connection wire 17, D1 is connected to a drain wire 14, and S2 is connected to a signal wire 15), on which the source electrodes S1 and S2 are provided. It has an interlayer insulating film 7 and a pixel electrode 8 on the interlayer insulating film 7 (the pixel electrode 8 has a gate electrode G1 via via

wires

18U and 18L provided in the opening of the interlayer insulating film 7 and the opening of the gate insulating film 3). It is connected to the. Further, it has a sensor unit 109 and a common electrode 10. The sensor unit 109 is in contact with or bonded to the pixel electrode 8.

An insulating etching stopper layer may be provided on the semiconductors SC1 and SC2, and semiconductors are provided at the interface between the semiconductors SC1 and SC2 and the source electrodes S1 and S2 and at the interface between the semiconductors SC1 and SC2 and the drain electrodes D1 and D2. It may have a contact layer having a resistance lower than 4.

Further, when the pixel electrode 8 is thick, there may be a gap in the portion where the pixel electrode 8 is not provided, or it may be filled with an insulating material.

In FIG. 12, the pixel electrode 8 is also the back gate electrode of the first thin film transistor. As a result, the operation becomes more stable than when the pixel electrode 8 is simply connected to the gate electrode G1 without covering the channel portion of the first thin film transistor. Further, although not shown in FIG. 12, a back gate electrode may be provided in the second thin film transistor, and a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the second thin film transistor becomes stable.

The insulating substrate 1 may be glass, but organic substances (for example, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PES (polyether sulfone), PI (polyimide), PC (polycarbonate), etc.) are suitable. As the gate electrodes G1 and G2, metals (for example, Al, Ti, Mo, Ta, etc. or alloys containing these as main components) are suitable. The gate insulating film 3 is preferably an organic substance (acrylic, epoxy, etc.) or an inorganic substance (SiO ₂ , SiN, etc.) or a laminate or mixture thereof. The semiconductors SC1 and SC2 are preferably organic semiconductors, oxide semiconductors, and amorphous Si. The source electrodes S1 and S2 and the drain electrodes D1 and D2 are preferably made of metal (for example, Al, Ti, Mo, Ta or the like or an alloy containing these as main components). The interlayer insulating film 7 is preferably an organic substance (acrylic, epoxy, etc.) or an inorganic substance (SiO ₂ , SiN, etc.) or a laminate or mixture thereof. The pixel electrode 8 is preferably made of a metal (for example, Al, Ti, Mo, Ta or the like or an alloy containing these as a main component) or a mixture of metal particles and a resin (Ag paste or the like). As the sensor unit 109, a pressure-sensitive medium 9, particularly an organic piezoelectric material (polyvinylidene fluoride, polyvinylidene fluoride / ethylene trifluoride copolymer, polylactic acid, porous electret type, etc.) is suitable, but it is a displacement-sensitive medium. Or a temperature sensitive medium. The common electrode 10 is preferably a metal (for example, Al, Ti, Mo, Ta, etc. or an alloy containing these as a main component).

However, flexibility is often desired for the sensor array, and in order to ensure flexibility, the main components of the insulating substrate 1, the gate insulating film 3, the interlayer insulating film 7, and the sensor unit 109 (pressure sensitive medium 9, etc.) are organic substances. Is particularly desirable.

Further, if the pixel electrode 8 is made of metal, it is easy to make the pixel electrode 8 thin, and it is possible to eliminate the gap between the interlayer insulating film 7 and the sensor unit 109 (pressure sensitive medium 9 or the like) other than the pixel electrode 8. It can improve the uniformity of measurement. If the pixel electrode 8 is a mixture of metal particles and resin, it is easy to thicken the pixel electrode 8, and a gap between the interlayer insulating film 7 and the sensor portion 109 (pressure sensitive medium 9 or the like) other than the pixel electrode 8 can be formed. It can be increased and a predetermined pressure can be obtained with a smaller force, that is, the sensitivity can be increased.

FIG. 12 shows the case of bottom gate and top contact, but the present disclosure is not limited to this, and top gate and bottom contact may be used.

[Fourth Embodiment]
The pixel circuit of the fourth embodiment of the present disclosure is shown in FIG. In FIG. 13, a third thin film transistor is further provided in the pixel circuit of FIG. 11, the drain electrode D3 of the third thin film transistor is connected to the pixel electrode 8, the source electrode S3 is connected to the common wiring 11, and the gate electrode G3 is It is connected to the reset wiring 13.

Before performing the measurement, a voltage (on voltage) for turning on the third thin film transistor is applied to the reset wiring 13 in a state where no stimulus (pressure or the like) is applied to the sensor unit 109. Then, the pixel electrode 8 is connected to the common wiring 11 via the third thin film transistor, and the electric charge accumulated in the pixel electrode 8 can be reduced to zero. Here, the common wiring 11 has the same potential as the common electrode 10. Then, a voltage (off voltage) for turning off the third thin film transistor is applied to the reset wiring 13, and a voltage Vdd is applied to the drain wiring 14.

The sensor unit 109, which changes the potential difference depending on the pressure like a piezoelectric element, has a potential difference of 0 when the stimulus (pressure, etc.) is 0 in a steady state, but depending on the past history, for example, the stimulus (pressure) until just before use. Etc.), an error due to the residual charge of the sensor unit 109 occurs, such that the potential difference is not 0 even if the stimulus (pressure or the like) is 0. In the sensor array according to the present embodiment, since the charge of the pixel electrode 8 can be reset by turning on the third thin film transistor immediately before the measurement, it is possible to eliminate the error caused by the residual charge of the sensor unit 109.

The gate-drain electrode capacitance of the first thin film transistor (including the pixel electrode 8 connected to the gate electrode G1 and the drain wiring 14 connected to the drain electrode D1) is Cgd1, and the gate-drain capacitance of the third thin film transistor (including the gate-drain capacitance). The reset wiring 13 connected to the gate electrode G3 and the capacitance of the pixel electrode 8 connected to the drain electrode D3 are set to Cgd3, and the capacitance between the pixel electrode 8 and the common electrode 10 is set to Cp. do. When an off voltage is applied to the reset wiring 13 to turn off the third thin film transistor, the potential of the pixel electrode 8 shifts by ΔVp = − {Vreset (on) -Vreset (off)} × Cgd3 / (Cgd3 + Cp + Cgd1). Further, when the potential of the drain wiring 14 is changed from 0 to Vdd, the potential of the pixel electrode 8 is deviated by ΔVp = Vdd × Cgd1 / (Cgd1 + Cp + Cgd3). In the case of an n-channel TFT, the former is negative and the latter is positive, and in the case of a p-channel TFT, the former is positive and the latter is negative, and in each case, there is an effect of canceling each other's voltage changes. Further, this voltage change needs to be sufficiently smaller than the maximum potential change amount of the pressure sensitive medium 9, and needs to be suppressed within 10% of the maximum potential change amount, for example. In order to suppress the above voltage change within 10% of the maximum potential change amount, | Vdd × Cgd1 / (Cgd1 + Cp + Cgd3)-{Vreset (on) -Vreset (off)} × Cgd3 / (Cgd3 + Cp + Cgd1) | ≦ Maximum potential change amount × It may be 0.1. Here, the maximum potential change amount is the pixel electrode potential change amount when the pressure of the maximum value in the pressure detection range set in the pressure sensor is applied from the state where the pressure is not applied to the pressure sensor. .. For example, when the maximum potential change amount is 4 [V], | Vdd × Cgd1 / (Cgd1 + Cp + Cgd3)-{Vreset (on) -Vreset (off)} × Cgd3 / (Cgd3 + Cp + Cgd1) | ≦ 0.4.

The measurement method is the same as that of the third embodiment, and the sensor array detection method in the third embodiment preferably includes, for example, the signal detection circuit, the drive detection circuit, and the signal detection method according to the first embodiment. Can be used for.

A specific example of FIG. 13 is shown in FIG. It has gate electrodes G1, G2, and G3 on the insulating substrate 1 (G2 is connected to the scanning wiring 12 and G3 is connected to the reset wiring 13), has a gate insulating film 3 on it, and has a gate insulating film 3 on it. It has semiconductors SC1, SC2, SC3, and has source electrodes S1, S2, S3 and drain electrodes D1, D2, D3 on it (S1 is connected to D2 via a connection wiring 17, and D3 is a gate insulating film. It is connected to the gate electrode G1 via the via wiring 18L provided in the opening of 3, D1 is connected to the drain wiring 14, S2 is connected to the signal wiring 15, S3 is connected to the common wiring 11), and above. It has an interlayer insulating film 7 and a pixel electrode 8 on the interlayer insulating film 7 (the pixel electrode 8 is connected to the drain electrode D3 via a via wiring 18U provided in the opening of the interlayer insulating film 7). Further, it has a sensor unit 109 (for example, a pressure sensitive medium 9) and a common electrode 10. The sensor unit 109 is in contact with or bonded to the pixel electrode 8.

An insulating etching stopper layer may be provided on the semiconductors SC1, SC2, and SC3, the interface between the semiconductors SC1, SC2, and SC3 and the source electrodes S1, S2, and S3, and the semiconductors SC1, SC2, SC3 and the drain electrode. A contact layer having a lower resistance than the semiconductors SC1, SC2, and SC3 may be provided at the interface between D1, D2, and D3.

In FIG. 14, the pixel electrode 8 is also the back gate electrode of the first thin film transistor. As a result, the operation becomes more stable than when the pixel electrode 8 is simply connected to the gate electrode G1 without covering the channel portion of the first thin film transistor. Further, although not shown in FIG. 14, a back gate electrode may be provided in the second thin film transistor, and a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the second thin film transistor becomes stable. Similarly, a back gate electrode may be provided on the third thin film transistor, and a pixel electrode potential, a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the third thin film transistor becomes stable.

The material of each component is the same as that of the third embodiment.

FIG. 14 shows the case of bottom gate and top contact, but the present disclosure is not limited to this, and top gate and bottom contact may be used.

[Fifth Embodiment]
The pixel circuit of the fifth embodiment of the present disclosure is shown in FIG. In FIG. 15, the sensor unit 109 (for example, the pressure sensitive medium 9) is of a type in which the potential difference changes depending on a stimulus (pressure or the like). One end of the sensor unit 109 is connected to the common electrode 10, the other end is connected to the gate electrode G1 of the first thin film transistor, and the drain electrode D1 of the first thin film transistor is connected to the power supply Vdd via the drain wiring 14, and the first The source electrode S1 of the thin film transistor is connected to the drain electrode D2 of the second thin film transistor, the gate electrode G2 of the second thin film transistor is connected to the scanning wiring 12, and the source electrode S2 of the second thin film transistor is connected to the signal wiring 15. Including the load resistance 20 in the detection circuit described later, the first thin film transistor is a drain ground circuit (source follower). Since the load resistor 20 is outside the array, a current flows through the signal wiring 15, so the impedance is low and noise is less likely to be mixed. Further, since it is a drain ground (source follower) circuit, only the current is amplified and the voltage is almost unchanged, so that it is not easily affected by the mobility and the variation of the threshold value of the first thin film transistor.

Further, the common wiring 11 is connected to the gate electrode G4 of the fourth thin film transistor, the drain electrode D4 of the fourth thin film transistor is connected to the power supply Vdd via the drain wiring 14, and the source electrode S4 of the fourth thin film transistor is the fifth. The thin film transistor drain electrode D5 of the thin film transistor, the gate electrode G5 of the fifth thin film transistor is connected to the scanning wiring 12, the source electrode S5 of the fifth thin film transistor is connected to the reference signal wiring 16, and the load resistance in the signal detection circuit. Including 20, the fourth thin film transistor is a drain ground circuit (source follower).

By observing the difference between the signal circuit composed of the sensor unit 109 and the first to second thin film transistors and the reference circuit composed of the fourth to fifth thin film transistors, the mobility variation and the threshold value change of the first thin film transistor can be determined. It is possible to cancel by the mobility variation or the threshold value change of the fourth thin film transistor, and to cancel the mobility variation or the mobility change of the second thin film transistor by the mobility variation or the threshold value change of the fifth thin film transistor. .. This is because the variation and characteristic change are greatly affected by the in-plane distribution, and therefore the variation and characteristic change of the thin film transistors formed in the same pixel are similar. In particular, the shape of the first thin film transistor (channel width and channel length) and the shape of the fourth thin film transistor (channel width and channel length) are made equal, and the shape of the second thin film transistor (channel width and channel length) and the fifth thin film transistor are made equal to each other. The shapes of the thin film transistors (channel width and channel length) should be equal.

As the sensor array detection method in the fifth embodiment, for example, the signal detection circuit, the drive detection circuit, and the signal detection method according to the second embodiment can be preferably used. At this time, the number of scanning wires 12 of the sensor array is N, and the number of signal wires 15 is M.

When the potential of the drain wiring 14 is changed from 0 to Vdd immediately before the measurement, the potential deviation of the pixel electrode 8 may be set to | Vdd × Cgd1 / (Cgd1 + Cp) | ≦ maximum potential change amount × 0.1. Is the same as in the third embodiment.

A specific example of FIG. 15 is shown in FIG. It has gate electrodes G1, G2, G4, and G5 on the insulating substrate 1 (G2 and G5 are connected to the scanning wiring 12), has a gate insulating film 3 on it, and semiconductors SC1, SC2, on the gate insulating film 3. It has SC4 and SC5, and has source electrodes S1, S2, S4, S5 and drain electrodes D1, D2, D4, D5 on it (S1 is connected to D2 via a connection wiring 17, and S4 is a connection wiring. It is connected to D5 via 17, D1 and D4 are connected to the drain wiring 14, S2 is connected to the signal wiring 15, S5 is connected to the reference signal wiring 16), and has an interlayer insulating film 7 on it. A pixel electrode 8 and a common wiring 11 are provided on the pixel electrode 8 (the pixel electrode 8 is connected to the gate electrode G1 via via

wires

18U and 18L provided in the opening of the interlayer insulating film 7 and the opening of the gate insulating film 3). The common wiring 11 is connected to the gate electrode G4 via via

wirings

18U and 18L provided in the opening of the interlayer insulating film 7 and the opening of the gate insulating film 3). Further, it has a sensor unit 109 (for example, a pressure sensitive medium 9) and a common electrode 10. The sensor unit 109 is in contact with or bonded to the pixel electrode 8.

An insulating etching stopper layer may be provided on the semiconductors SC1, SC2, SC4, and SC5, or the interface between the semiconductors SC1, SC2, SC4, SC5 and the source electrodes S1, S2, S4, S5 and the semiconductor SC1, A contact layer having a lower resistance than the semiconductors SC1, SC2, SC4, and SC5 may be provided at the interface between the SC2, SC4, and SC5 and the drain electrodes D1, D2, D4, and D5.

Further, when the pixel electrode 8 is thick, there may be a gap in the portion where the pixel electrode 8 is not provided, or it may be filled with an insulating material. The common wiring 11 may or may not be in contact with the sensor unit 109.

In FIG. 16, the pixel electrode 8 is the back gate electrode of the first thin film transistor, and the common wiring 11 is the back gate electrode of the fourth thin film transistor. As a result, the pixel electrode 8 is only connected to the gate electrode G1 without covering the channel portion of the first thin film transistor, or the common wiring 11 is connected to the gate electrode G4 without covering the channel portion of the fourth thin film transistor. The operation is more stable than when it is just connected. Further, although not shown in FIG. 16, a back gate electrode may be provided in the second thin film transistor, and a pixel electrode potential, a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the second thin film transistor becomes stable. Similarly, a back gate electrode may be provided on the fifth thin film transistor, and a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the fifth thin film transistor becomes stable.

The material of each component is the same as that of the third embodiment.

FIG. 16 shows the case of bottom gate and top contact, but the present disclosure is not limited to this, and top gate and bottom contact may be used.

[Sixth Embodiment]
The pixel circuit of the sixth embodiment of the present disclosure is shown in FIG. In FIG. 17, a third thin film transistor is further provided in the pixel circuit of FIG. 15, the drain electrode D3 of the third thin film transistor is connected to the pixel electrode 8, the source electrode S3 is connected to the common wiring 11, and the gate electrode G3 is It is connected to the reset wiring 13.

Before measuring the pressure, a voltage (on voltage) for turning on the third thin film is applied to the reset wiring 13 in a state where no stimulus (pressure or the like) is applied to the sensor unit 109. Then, the pixel electrode 8 is connected to the common wiring 11 via the third thin film transistor, and the electric charge accumulated in the pixel electrode 8 can be reduced to zero. Then, a voltage (off voltage) for turning off the third thin film transistor is applied to the reset wiring 13, and a power supply Vdd is applied to the drain wiring 14.

When an off voltage is applied to the reset wiring 13 to turn off the third thin film transistor, the potential of the pixel electrode 8 shifts by ΔVp = (Vreset (off) -Vreset (on)) × Cgd3 / (Cgd3 + Cp + Cgd1). When the potential of the drain wiring 14 is changed from 0 to Vdd, the potential of the pixel electrode 8 deviates by ΔVp = Vdd × Cgd1 / (Cgd1 + Cp + Cgd3), and both have the effect of canceling each other, as in the second embodiment. .. Similar to the second embodiment, | Vdd × Cgd1 / (Cgd1 + Cp + Cgd3)-{Vreset (on) -Vreset (off)} × Cgd3 / (Cgd3 + Cp + Cgd1) | ≦ Maximum potential change amount × 0.1.

The measurement method is the same as that of the fifth embodiment, and the sensor array detection method in the sixth embodiment preferably includes, for example, the signal detection circuit, the drive detection circuit, and the signal detection method according to the second embodiment. Can be used for.

A specific example of FIG. 17 is shown in FIG. The gate electrodes G1, G2, G3, G4, and G5 are provided on the insulating substrate 1 (G2 and G5 are connected to the scanning wiring 12 and G3 is connected to the reset wiring 13), and the gate insulating film 3 is placed on the gate electrodes G1 and G2, G3, G4, and G5. It has semiconductors SC1, SC2, SC3, SC4, SC5 on it, and has source electrodes S1, S2, S3, S4, S5 and drain electrodes D1, D2, D3, D4, D5 on it ( S1 is connected to D2 via the connecting wiring 17, D3 is connected to the gate electrode G1 via the via wiring 18L provided in the opening of the gate insulating film 3, and S4 is connected to D5 via the connecting wiring 17. , D1 and D4 are connected to the drain wiring 14, S2 is connected to the signal wiring 15, S5 is connected to the reference signal wiring 16, S3 is connected to the common wiring 11), and the interlayer insulating film 7 is provided therein. A pixel electrode 8 and a common wiring 11 are provided on the pixel electrode 8 (the pixel electrode 8 is connected to the drain electrode D3 via a via wiring 18U provided in the opening of the interlayer insulating film 7, and the common wiring 11 is an interlayer insulating film. It is connected to the gate electrode G4 via via

wires

18U and 18L provided in the openings of the gate 7 and the gate insulating film 3.). Further, it has a sensor unit 109 (for example, a pressure sensitive medium 9) and a common electrode 10. The sensor unit 109 is in contact with or bonded to the pixel electrode 8.

An insulating etching stopper layer may be provided on the semiconductors SC1, SC2, SC3, SC4, and SC5, or the semiconductors SC1, SC2, SC3, SC4, SC5 and the source electrodes S1, S2, S3, S4, and S5. And the interface between the semiconductors SC1, SC2, SC3, SC4, SC5 and the drain electrodes D1, D2, D3, D4, D5 have a contact layer with lower resistance than the semiconductors SC1, SC2, SC3, SC4, SC5. May be good.

The material of each component is the same as that of the third embodiment.

In FIG. 18, the pixel electrode 8 is the back gate electrode of the first thin film transistor, and the common wiring 11 is the back gate electrode of the fourth thin film transistor. As a result, the pixel electrode 8 is only connected to the gate electrode G1 without covering the channel portion of the first thin film transistor, or the common wiring 11 is connected to the gate electrode G4 without covering the channel portion of the fourth thin film transistor. The operation is more stable than when it is just connected. Further, although not shown in FIG. 12, a back gate electrode may be provided in the second thin film transistor, and a pixel electrode potential, a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the second thin film transistor becomes stable. Similarly, a back gate electrode may be provided on the third thin film transistor, and a pixel electrode potential, a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the third thin film transistor becomes stable. Similarly, a back gate electrode may be provided on the fifth thin film transistor, and a common electrode potential, a GND potential, or a specific constant potential may be connected thereto. As a result, the operation of the fifth thin film transistor becomes stable.

FIG. 18 shows the case of bottom gate and top contact, but the present disclosure is not limited to this, and top gate and bottom contact may be used.

Further, when the sensor unit 109 is oriented so that the potential on the pixel electrode 8 side rises at the time of + stimulation (pressurization, etc.), the signal voltage at the time of no stimulation is adjusted to somewhere between 0 and +2 [V]. Is good. Then, when an AD converter having a 0 to + 5 V input is used in signal detection, a detection range of 5 to 3 V can be used. When the sensor unit 109 is oriented so that the potential on the pixel electrode 8 side drops during + stimulation (pressurization, etc.), it is better to adjust the signal voltage without stimulation to somewhere between +3 and +5 [V]. .. Then, when using an AD converter with 0 to + 5V input, a detection range of 3 to 5V can be used.

Further, when the sensor unit 109 is oriented so that the potential on the pixel electrode 8 side rises at the time of + stimulation (pressurization, etc.), the voltage Vbase to be added by the differential amplifier circuit 24 is somewhere between 0 and +2 [V]. It is better to adjust to. Then, when using an AD converter with 0 to + 5V input, a detection range of 5 to 3V can be used. When the sensor unit 109 is oriented so that the potential on the pixel electrode 8 side drops during + stimulation (pressurization, etc.), the voltage Vbase added by the differential amplifier circuit 24 is adjusted to somewhere between +3 and +5 [V]. It is better to do it. Then, when using an AD converter with 0 to + 5V input, a detection range of 3 to 5V can be used.

[7th Embodiment]
A health state estimation system using the signal detection circuit or drive detection circuit of the first embodiment or the signal detection circuit or drive detection circuit of the second embodiment will be described with reference to FIG. FIG. 19 is a block diagram showing an example of the nursing care data collection / determination system of the present disclosure. The long-term care data collection / judgment system includes a long-term care sensor device and a data collection / judgment device. The care sensor device is a signal detection circuit of the first or second embodiment to which a communication circuit is added, and includes a signal detection circuit, a communication circuit, a pressure-sensitive sensor array, a microcomputer, and a drive circuit. The communication circuit of the care sensor device is a circuit that communicates data with an external circuit and is capable of wired communication and wireless communication, but wireless communication such as Bluetooth (registered trademark) and Wi-Fi (registered trademark) is particularly preferable. Yes, and it is preferable to connect to the Internet. The data collection / judgment device has a communication circuit, a computer, and a database. (1) The data detected by the long-term care sensor device is stored in the database as it is or after being processed. At that time, the medical condition of the care recipient can also be saved together. (2) Using artificial intelligence, analyze big data in the database by machine learning or the like to clarify the relationship between posture and medical condition. (3) The data detected by the long-term care sensor device is compared with the data in the database to determine the medical condition. It is possible to perform three operations.

One data collection / judgment device may be connected to only one care sensor device, or one data collection / judgment device may be connected to a plurality of care sensor devices. When connecting to only one long-term care sensor device, data can be easily exchanged, but the response speed of the long-term care sensor device needs to be high. Alternatively, the speed of the data collection / judgment device does not have to be very high. When connecting to a plurality of long-term care sensor devices, data exchange becomes complicated, but the operating speed of each long-term care sensor device may be slow. Alternatively, the speed of the data collection / judgment device needs to be high.

Further, although the computer and the database are in one data collection / judgment device in FIG. 19, the computer and the database may communicate with each other via a communication circuit.

An example of the long-term care sensor device is shown in FIG. In FIG. 20, the care sensor device 200 is described so as to be visible on the bed 201, but in reality, the sheets are placed on the bed 201 and the care recipient is asked to sleep on the sheets. The nursing care sensor device 200 of FIGS. 20A and 20B has a large sheet-shaped sensor array 200A (for example, a pressure sensor array) on the bed. 200G is a drive circuit, 200S is a signal detection circuit, and 200C is a control / communication circuit. The short side may be the driving side as shown in FIG. 20A, or the long side may be the driving side as shown in FIG. 20B.

The care sensor device 200 of FIG. 20C has a plurality of band-shaped sensor arrays 200A, connects all the short sides of the band-shaped sensor array 200A to the signal detection circuit 200S, and drives wiring next to each other on the long side of the band. By connecting with the inter-connection component 200WG, all the gate wirings are connected to one drive circuit 200G, and one control / communication circuit 200C is provided. The care sensor device 200 of FIG. 20D has a plurality of small sheet-shaped sensor arrays 200A, and the signal wirings of the small sheet-shaped sensor arrays 200A are connected to each other by a signal wiring connection component 200WS to connect the signal detection circuit 200S. The drive wirings of the small sheet-shaped sensor array 200A are connected to each other by the drive wiring connection component 200WG to be connected to one drive circuit 200G, and have one control / communication circuit 200C. 20 (c) and 20 (d) replace the large sheet-shaped sensor array of FIG. 20 (a) with a plurality of strip-shaped sensor arrays or a plurality of small sheet-shaped sensor arrays. The drive side and the signal side may be interchanged as shown in FIG. 20 (b). These operate as one care sensor device 200.

The nursing care sensor device 200 of FIG. 20 (e) has a plurality of band-shaped sensor arrays 200A, connects the short side of the band-shaped sensor array 200A to the signal detection circuit 200S, and connects each band-shaped sensor to the plurality of drive circuits 200G. The long sides of the array 200A are connected to each other, and a plurality of control / communication circuits 200C are provided. The care sensor device 200 of FIG. 20F has a plurality of small sheet-shaped sensor arrays 200A, and the signal wirings of the small sheet-shaped sensor arrays 200A are connected to each other by a signal wiring connection component 200WS to form a strip-shaped set. Then, it is connected to the signal detection circuit 200S, each band-shaped set is connected to the plurality of drive circuits 200G, and has a plurality of control / communication circuits 200C. 20 (e) and 20 (f) operate as a plurality of care sensor devices 200.

Further, when the sensor array is applied to the determination of the posture, the determination is possible even if the stimulation values (pressure, etc.) of all the pixels are not accurately measured. Even if a problem occurs in the detection unit of one pixel and it becomes abnormal data, it can be determined by interpolating from the data of surrounding pixels. Further, even if a problem occurs in the detection unit of a plurality of pixels and the data becomes abnormal, it can be determined by interpolating from the data of the surrounding pixels. In this case, if the pixels in which the problem occurs are dispersed, it is easier to interpolate the data as compared with the case where the pixels are densely packed. However, even when it is dense, constant interpolation is possible. The sensor array is not limited to the pressure sensor. Specifically, a displacement sensor or a temperature sensor can be used as a sensor array. That is, it can also be applied to a displacement sensor array and a temperature sensor array. Furthermore, it can be applied to a composite sensor array having both a temperature sensor and a pressure sensor, for example.

Further, as shown in FIG. 22, it is preferable to provide the drain wiring 14 with a current limiting circuit 40. When a short circuit occurs between the drain wiring 14 and other wiring (scanning wiring 12, signal wiring 15, reference signal wiring 16, common electrode 37, etc.) in the array, it prevents an excessive current from flowing. At that time, as shown in FIG. 22A, the power supply may be branched after passing through one current limiting circuit 40 and connected to all the drain wirings 14, but in that case, due to an abnormality at one place. The voltage of all the drain wires 14 drops, and the entire sensor array shows an abnormal value. Therefore, as shown in FIG. 22B, it is desirable that the power supply is branched, each of the branches passes through the current limiting circuit 40, and then connected to the individual drain wiring 14. Normally, since the drain wiring 14 is provided for each column or row, it is preferable to provide one current limiting circuit 40 for each drain wiring 14. In this case, the voltage of one drain wiring 14 drops due to an abnormality at one place, and the sensor in one column or one row shows an abnormal value, but the abnormality in one column or one row is corrected by interpolation. be able to. Alternatively, as shown in FIG. 22C, each of the plurality of current limiting circuits 40 may be assigned a plurality of column wirings or row wirings. At that time, as shown in FIG. 22D, the column wiring or row wiring in charge of one current limiting circuit 40 is not adjacent to each other, and the column wiring or row wiring in charge of another current limiting circuit 40 is provided between them. It is possible to prevent an abnormality in one place from becoming a continuous abnormality of a plurality of columns or a plurality of rows, and interpolation becomes possible. The current limiting circuit 40 is not limited to the circuit shown in FIG. 22A, and may be another type of current limiting circuit.

As described above, by applying the signal detection circuit or drive detection circuit of the first embodiment or the signal detection circuit or drive detection circuit of the second embodiment, the long-term care data collection capable of estimating the health condition can be performed. -A judgment system can be provided.

(Example 1)
The signal detection circuit of FIG. 1 was manufactured. The first switching circuit 101 is an analog multiplexer with 8 inputs and 1 output, the load resistance 20 is a metal film resistance of 1 MΩ, the voltage detection amplifier 53 is a voltage follower using an operational amplifier, and the second switching circuit 102 is an analog multiplexer with 8 inputs and 1 output. The AD converter 25 has a 0 to + 5 V input and a 0 to 255 level (8 bit) output. This circuit has M ₁ = 8, M ₂ = 8, L = 8, and corresponds to a sensor array having M = 64 signal wires 15. An oscillation prevention circuit was incorporated in the voltage detection amplifier 53, and an AD converter input protection circuit was provided on the output side of the voltage detection amplifier 53.

The first switching circuit 101 was controlled by using a microcomputer and a 3-bit counter, and the second switching circuit 102 and the AD converter 25 were also controlled by the same microcomputer to detect the signal of the pressure sensor array of 1 row and 64 columns. The measurement time of the AD converter 25 is (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, the time constant of the output response of the second switching circuit 102 is about 3 μs, and the time constant of the output response of the first switching circuit 101. Was about 500 μs. The time constant of the response of the output of the first switching circuit 101, since (M 2 _-1) × AD converter measurement time = small compared to 1092Myuesu, the signal detection method of FIG. 5, signals from the stable high I was able to measure the accuracy.

(Example 2)
The microcomputer and the counter used in the first embodiment were added to the signal detection circuit of the first embodiment as the control circuit 5 and the counter 49, and the drive circuit 6 was further added to prepare the drive detection circuit of FIG. The drive circuit outputs + 15V as the on voltage or -15V as the off voltage.

Using this drive detection circuit, the signal of the pressure sensor array of 8 rows and 64 columns was detected by the signal detection method of FIG. The measurement time of the AD converter 25 is (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, the time constant of the output response of the second switching circuit 102 is about 3 μs, and the time constant of the output response of the first switching circuit 101. Was about 500 μs. The time constant of the response of the output of the first switching circuit 101, since (M 2 _-1) × AD converter measurement time = small compared to 1092Myuesu, the signal detection method of FIG. 5, signals from the stable high I was able to measure the accuracy.

(Example 3)
The signal detection circuit of FIG. 7 was manufactured. Each set of analog multiplexers (8 inputs, 1 output x 2 sets) is used for the first switching circuit 101 and the third switching circuit 103, and the

load resistors

20 and 21 are 1 MΩ metal film resistors, the voltage detection amplifier 53, and the like. 54 is a non-inverting amplifier circuit using an operational amplifier, the differential amplifier circuit 24 is a circuit using an operational amplifier, the second switching circuit 102 is an analog multiplexer with 8 inputs and 1 output, and the AD converter 25 is 0 to 255 levels (8 bits) with 0 to + 5 V inputs. It was used as an output. This circuit has M ₁ = 8, M ₂ = 8, L = 8, and corresponds to a sensor array with M = 64 signal wires and 64 reference signal wires. An oscillation prevention circuit was incorporated in the

voltage detection amplifiers

53 and 54, and an AD converter input protection circuit was provided on the output side of the

voltage detection amplifiers

53 and 54.

The first switching circuit 101 and the third switching circuit 103 are controlled by using a microcomputer and a 3-bit counter, and the second switching circuit 102 and the AD converter 25 are also controlled by the same microcomputer. A signal was detected. The measurement time of the AD converter 25 is (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, the time constant of the output response of the second switching circuit 102 is about 3 μs, and the time constant of the output response of the first switching circuit 101. Was about 500 μs. The time constant of the response of the output of the first switching circuit 101, since (M 2 _-1) × AD converter measurement time = small compared to 1092Myuesu, the signal detection method of FIG. 9, signals from the stable high I was able to measure the accuracy.

(Example 4)
The microcomputer and the counter used in the third embodiment were added to the signal detection circuit of the third embodiment, and the drive circuit 6 was further added to prepare the drive detection circuit of FIG. The drive circuit 6 outputs + 15V as an on voltage or -15V as an off voltage.

Using this drive detection circuit, the signal of the pressure sensor array of 8 rows and 64 columns was detected by the signal detection method of FIG. The measurement time of the AD converter 25 is (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, the time constant of the output response of the second switching circuit 102 is about 3 μs, and the first switching circuit 101 and the third switching circuit 103. The time constant of the response of the output of was about 500 μs. The time constant of the response of the output of the first switching circuit 101 and the third switching circuit _103, since _(M 2 -1) × AD converter measurement time = small compared to 1092Myuesu, the signal detection method of FIG. 9, the signal Was able to measure with high accuracy after it became stable.

(Example 5)
The sensor array of FIG. 12 was manufactured. Using a PET film on a glass substrate as the insulating substrate 1, Mo was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form gate electrodes G1 and G2 and scanning wiring 12. Next, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form a gate insulating film 3 with an opening. Further, the amorphous InGaZnO was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form semiconductor patterns SC1 and SC2. _{Then, a SiO 2} pattern was formed as an etching stopper layer on the portions of the semiconductor patterns SC1 and SC2 to be channels (not shown).

Further, Mo is formed into a film, resist film, pattern exposure, development, etching, and resist removal to remove the source electrodes S1 and S2, the drain electrodes D1 and D2, the connection wiring 17 (between S1 and D2), the signal wiring 15, and the drain. The wiring 14 and the via wiring 18L (lower half between the pixel electrode and G1) were formed.

Then, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form an interlayer insulating film 7 with an opening. Next, Mo was formed into a film, a resist film, pattern exposure, development, etching, and resist removal to form a pixel electrode 8 and a via wiring 18U (upper half between the pixel electrodes 8 and G1). At this time, the pixel electrode 8 was connected to the gate electrode G1 by via

wires

18U and 18L.

Further, a pressure-sensitive medium (polyvinylidene fluoride triethylene ethylene copolymer, polarized) having Mo attached to the entire surface of one side is installed so that the pressure-sensitive medium side is in contact with the pixel electrode 8, and the sensor unit 109 ( The pressure-sensitive medium 9) and the common electrode 10 were used. Then, the glass substrate was peeled off from the PET film which is the insulating substrate 1. Since the pixel electrode 8 is thin, the sensor unit 109 (pressure sensitive medium 9) is in contact with the interlayer insulating film 7 in a portion other than the pixel electrode 8, and there is almost no gap.

Here, the gate-drain capacitance (including the pixel electrode-drain wiring capacitance) of the first thin film transistor was Cgd1 = 1.53 pF, and the pixel electrode 8 / common electrode 10 capacitance Cp = 63.1 pF.

Using the detection circuit of FIG. 23, + 1V is applied to the common electrode 10, + 10V is applied to the drain wiring 14, an on voltage + 15V is applied to one of the scanning wirings 12, and an off voltage of -15V is applied to the other, and a pressure-dependent signal for one pixel is applied. Got By switching the analog switch 22, a pressure-dependent signal for one line was obtained. The same operation was performed by changing the on-voltage position of the scanning wiring 12, and pressure-dependent signals of all pixels were obtained. From the pressure-dependent signal, the pressure of each pixel can be known. Further, since the potential change of the pixel electrode 8 when Vdd is applied is 0.24 V and the maximum potential change amount of the pressure sensitive medium 9 (at a pressure of 800 kPa) is 4 V, the error due to the potential change of the pixel electrode 8 when Vdd is applied is It is sufficiently small, 6% of the maximum potential change amount.

(Example 6)
The sensor array of FIG. 14 was manufactured. Using a polyimide film on a glass substrate as the insulating substrate 1, Mo is formed, resist filmed, pattern exposed, developed, etched, and resist removed to form gate electrodes G1, G2, G3, scanning wiring 12, and reset wiring 13. Formed. Next, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form a gate insulating film 3 with an opening. Further, the amorphous InGaZnO was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form semiconductor patterns SC1, SC2, and SC3. _{Then, a SiO 2} pattern was formed as an etching stopper layer on the portions of the semiconductor patterns SC1, SC2, and SC3 to be channels (not shown).

Further, Mo is formed into a film, resist film, pattern exposure, development, etching, and resist removal to remove the source electrodes S1, S2, S3, drain electrodes D1, D2, D3, connection wiring 17 (between S1 and D2), and vias. The wiring 18L (between D3-G1), the signal wiring 15, and the drain wiring 14 were formed.

Then, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form an interlayer insulating film 7 with an opening. Next, the Ag paste was screen-printed to form the pixel electrode 8 and the via wiring 18U (between the pixel electrodes 8 and D3). At this time, the pixel electrode 8 was connected to the drain electrode D3 and the gate electrode G1 by the via

wires

18U and 18L.

Further, a pressure-sensitive medium having Mo on the entire surface of one side (polyvinylidene fluoride triethylene ethylene copolymer, polarization-treated) is installed so that the pressure-sensitive medium side is bonded to the pixel electrode 8, and the sensor unit 109 ( The pressure-sensitive medium 9) and the common electrode 10 were used. Further, the glass substrate was peeled off from the polyimide film which is the insulating substrate 1. Since the pixel electrode 8 is thick, the sensor unit 109 (pressure sensitive medium 9) is not in contact with the interlayer insulating film 7, and there is a gap in the portion where the pixel electrode 8 is not provided.

Here, the gate-drain capacitance of the first thin film transistor (including the capacitance between the pixel electrode and the drain wiring) Cgd1 = 1.53pF, and the gate-drain capacitance of the third thin film transistor (including the capacitance between the pixel electrode and the drain wiring). ) Cgd3 = 0.69pF, and the capacitance between the pixel electrode 8 and the common electrode 10 was Cp = 63.1pF.

Using the detection circuit of FIG. 24, first, an on-voltage + 15V was applied to the reset wiring 13 with + 1V to the common electrode 10 and 0V to the drain wiring 14. Next, the potential of the reset wiring 13 was set to an off voltage of -15V, and the potential of the drain wiring 14 was set to + 15V.

An on voltage of + 15V and an off voltage of -15V were applied to one of the scanning wires 12 to obtain a pressure-dependent signal for one pixel. By switching the analog switch 22, a pressure-dependent signal for one line was obtained. The same operation was performed by changing the on-voltage position of the scanning wiring 12, and pressure-dependent signals of all pixels were obtained. From the pressure-dependent signal, the pressure of each pixel can be known. Further, since the potential change of the pixel electrode 8 when Vreset is off and Vdd is applied is 0.027V and the maximum potential change amount of the pressure sensitive medium 9 (at a pressure of 800 kPa) is 4V, the pixel electrode 8 when Vreset is off and Vdd is applied is 4V. The error due to the potential change is 0.7% of the maximum potential change, which is sufficiently small.

(Example 7)
The sensor array of FIG. 16 was manufactured. Using a PET film on a glass substrate as the insulating substrate 1, Mo was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form gate electrodes G1, G2, G4, G5, and scanning wiring 12. .. Next, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form a gate insulating film 3 with an opening. Further, the amorphous InGaZnO was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form semiconductor patterns SC1, SC2, SC4, and SC5. _{Then, a SiO 2} pattern was formed as an etching stopper layer on the channel portions of the semiconductor patterns SC1, SC2, SC4, and SC5 (not shown).

Further, Mo is formed into a film, resist is formed, pattern is exposed, developed, etched, and resist is removed to remove the source electrodes S1, S2, S4, S5, drain electrodes D1, D2, D4, D5, and connection wiring 17 (S1-D2). (Between), connection wiring 17 (between S4-D5), signal wiring 15, reference signal wiring 16, drain wiring 14, common wiring 11, via wiring 18L (lower half between pixel electrodes 8 and G1), via wiring 18L (common) The lower half of the wiring 11-G4) was formed.

Then, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form an interlayer insulating film 7 with an opening. Next, the Ag paste is screen-printed to form the pixel electrode 8, the common wiring 11, the via wiring 18U (upper half between the pixel electrodes 8 and G1), and the via wiring 18U (the upper half between the common wiring 11 and G4). bottom. At this time, the pixel electrode 8 was connected to the gate electrode G1, and the common wiring 11 was connected to the gate electrode G4.

Further, a pressure-sensitive medium having Mo on the entire surface of one side (polyvinylidene fluoride triethylene ethylene copolymer, polarization-treated) is installed so that the pressure-sensitive medium side is bonded to the pixel electrode 8, and the sensor unit 109 ( The pressure-sensitive medium 9) and the common electrode 10 were used. Further, the glass substrate was peeled off from the PET film which is the insulating substrate 1.

Using the detection circuit of FIG. 25, + 1V is applied to the common electrode 10, + 10V is applied to the drain wiring 14, an on voltage + 15V is applied to one of the scanning wirings 12, and an off voltage of -15V is applied to the other, and a pressure-dependent signal for one pixel is applied. Got By switching the analog switch 22, a pressure-dependent signal for one line was obtained. The same operation was performed by changing the on-voltage position of the scanning wiring 12, and pressure-dependent signals of all pixels were obtained. From the pressure-dependent signal, the pressure of each pixel can be known. Further, since the potential change of the pixel electrode 8 when Vdd is applied is 0.24 V and the maximum potential change amount of the pressure sensitive medium 9 (at a pressure of 800 kPa) is 4 V, the error due to the potential change of the pixel electrode 8 when Vdd is applied is It is sufficiently small, 6% of the maximum potential change amount. The detection circuit was set to Vbase = 0.5 [V].

(Example 8)
The sensor array of FIG. 18 was manufactured. Using a polyimide film on a glass substrate as the insulating substrate 1, Mo is formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal, and the gate electrodes G1, G2, G3, G4, G5, scanning wiring 12, The reset wiring 13 was formed. Next, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form a gate insulating film 3 with an opening. Further, the amorphous InGaZnO was formed by film formation, resist film formation, pattern exposure, development, etching, and resist removal to form semiconductor patterns SC1, SC2, SC3, SC4, and SC5. _{Then, a SiO 2} pattern was formed as an etching stopper layer on the channel portions of the semiconductor patterns SC1, SC2, SC3, SC4, and SC5 (not shown).

Further, Mo is formed into a film, resist is formed, pattern is exposed, developed, etched, and resist is removed, and the source electrodes S1, S2, S3, S4, S5, drain electrodes D1, D2, D3, D4, D5, and connection wiring 17 are formed. (Between S1-D2), via wiring 18L (between D3-G1), connection wiring 17 (between S4-D5), signal wiring 15, drain wiring 14, via wiring 18L (lower half of common wiring 11-G4 wiring) Was formed.

Then, the photosensitive acrylic was formed into a film, exposed to a pattern, and developed to form an interlayer insulating film 7 with an opening. Next, the Ag paste was screen-printed to form the pixel electrode 8, the via wiring 18U (between the pixel electrodes 8 and D1), the common wiring 11, and the via wiring 18U (the upper half between the common wiring 11 and G4). At this time, the pixel electrode 8 was connected to the drain electrode D3 and the gate electrode G1, and the common wiring 11 was connected to the gate electrode G4.

Further, a pressure-sensitive medium having Mo on the entire surface of one side (polyvinylidene fluoride triethylene ethylene copolymer, polarization-treated) is installed so that the pressure-sensitive medium side is bonded to the pixel electrode 8, and the sensor unit 109 ( The pressure-sensitive medium 9) and the common electrode 10 were used. Further, the glass substrate was peeled off from the polyimide film which is the insulating substrate 1.

Using the detection circuit of FIG. 26, first, an on-voltage + 15V was applied to the reset wiring 13 with + 1V to the common electrode 10 and 0V to the drain wiring 14. Next, the potential of the reset wiring 13 was set to an off voltage of -15V, and the potential of the drain wiring 14 was set to + 15V.

An on-voltage of + 15V and an off-voltage of -15V were applied to one of the scanning wires 12, and a signal on the pressure-sensitive side of one pixel was obtained. By switching the analog switch 22, a signal on the non-pressure sensitive side was obtained. Further, by switching the analog switch 22, signals on the pressure-sensitive side and the non-pressure-sensitive side for one line were obtained. The same operation was performed by changing the on-voltage position of the scanning wiring 12, and signals on the pressure-sensitive side and the non-pressure-sensitive side of all the pixels were obtained. The pressure of each pixel can be found from the value obtained by subtracting the non-pressure sensitive signal from the pressure sensitive signal. Further, since the potential change of the pixel electrode 8 when Vreset is off and Vdd is applied is 0.027V and the maximum potential change amount of the pressure sensitive medium 9 (at a pressure of 800 kPa) is 4V, the pixel electrode 8 when Vreset is off and Vdd is applied is 4V. The error due to the potential change is 0.7% of the maximum potential change, which is sufficiently small. The detection circuit was set to Vbase = 1.0 [V].

(Comparative Example 1)
The signal detection circuit of FIG. 30 was manufactured. The switching circuit 100 uses eight analog multiplexers with 8 inputs and 1 output, the load resistance 122 is a metal film resistance of 1 MΩ, the voltage detection amplifier 123 is a voltage follower using an operational amplifier, and the AD converter 124 is 0 to 255 levels with 0 to + 5 V inputs ( 8 bits) Output. A load resistor 122 and 64 voltage detection amplifiers 123 were used in this circuit. This circuit corresponds to a sensor array having 64 signal wires 15.

The switching circuit 100 was controlled by using a microcomputer, and the AD converter 124 was also controlled by the same microcomputer to detect the signal of the pressure sensor array of 1 row and 64 columns. The measurement time of the AD converter 124 was (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, and the time constant of the output response of the switching circuit 100 was about 500 μs. Since the time constant of the output response of the switching circuit 100 is larger than the AD converter measurement time = 156 μs, the signal is not stable and the measurement accuracy is poor.

(Comparative Example 2)
Using the signal detection circuit of Example 2, the signal of the pressure sensor array of 8 rows and 64 columns was detected by the signal detection method of FIG. The measurement time of the AD converter 25 is (preparation time 104 μs + actual measurement time 52 μs) = 156 μs, the time constant of the output response of the second switching circuit 102 is about 3 μs, and the time constant of the output response of the first switching circuit 101. Was about 500 μs. Since the time constant of the output response of the first switching circuit 101 is larger than the AD converter measurement time = 156 μs, the signal is not stable and the measurement accuracy is poor by the signal detection method of FIG.

This disclosure can be used as a signal detection circuit or a drive detection circuit for various sensor arrays. Further, it can be used for various sensor arrays using a type of sensor unit in which the potential difference changes. Furthermore, it can be used for sensor systems including a health condition estimation system.

1 ... Insulation substrate G1, G2, G3, G4, G5 ... Gate electrode 3 ... Gate insulating film SC1, SC2, SC3, SC4, SC5 ... Semiconductor pattern S1, S2, S3, S4, S5 ... Source electrodes D1, D2, D3 , D4, D5 ... Drain electrode 5 ... Control circuit 6 ... Drive circuit 7 ... Interlayer insulating film 8 ... Pixel electrode 9 ... Pressure sensitive medium (type in which the potential difference changes)
10 ... Common electrode 11 ... Common wiring 12 ... Scanning wiring 13 ... Reset wiring 14 ... Drain wiring 15 ... Signal wiring 16 ... Reference signal wiring 17 (S1-D2, S4-D5) ...

Connection wiring

18L, 18U ... Via

wiring

20, 21 ... Load resistance 22 ... Analog switch 24 ... Differential amplification circuit 25 ... Analog-digital conversion circuit (AD converter)
31 ... Thin film transistor 32 ... Scanning wiring 33 ... Signal wiring 36 ... Power supply wiring 38 ... TFT
39 ... Pressure-sensitive medium (type in which resistance changes)
40 ... Current limiting circuit 41 ... First thin film transistor 42 ... Second thin film transistor 43 ... Drain resistance 44 ... Scanning wiring 45 ... Signal wiring 48 ... Control signal (digital wiring)
49 ...

Counters

53, 54 ... Voltage detection amplifier 100 ... Switching circuit 101 ... First switching circuit 102 ... Second switching circuit 103 ... Third switching circuit 109 ... Sensor unit 115 ... Signal wiring 122 ... Load resistance 123 ... Voltage Detection amplifier 124 ... AD converter 125 ... Control circuit 126 ... Drive circuit 127 ... Scanning wiring 130 ... Pressure-sensitive medium (type in which resistance changes)
140 ... Inorganic pressure-sensitive medium (type in which the potential difference changes)
200 ... Nursing sensor device 200A ... Pressure sensor array 200G ... Drive circuit 200S ... Signal detection circuit 200C ... Control / communication circuit 200WG ... Drive wiring connection parts 200WS ... Signal wiring connection parts 201 ... Bed T1 ... TFT1
T2 ... TFT2
T3 ... TFT3
T4 ... TFT4

Claims

A signal detection circuit for a sensor array that detects an external stimulus of the sensor unit corresponding to the intersection of a matrix of a plurality of scanning wires and a plurality of signal wires.
The plurality of signal wirings are divided into M 2 blocks, M 1 each.
In each of the two M blocks,
A first switching circuit M 1 present in the signal line is connected to the input,
A load resistor and a voltage detection amplifier connected to the output of the first switching circuit are provided.
M A second switching circuit in which each output from the two blocks is connected to an input,
With the AD converter connected to the output of the second switching circuit,
Signal detection circuit with.
The signal detection circuit according to claim 1, wherein the first switching circuit is an analog multiplexer.
The signal detection circuit, the control circuit, and the drive circuit according to claim 1 or 2 are provided.
The drive circuit is a circuit that applies an on voltage or an off voltage to the scanning wiring.
A drive detection circuit in which the first switching circuit, the second switching circuit, the AD converter, and the drive circuit are controlled by the control circuit.
The drive detection circuit according to claim 3, wherein the control circuit controls the first switching circuit via a counter.
The control circuit
In one block of the M 2 pieces of the blocks,
After switching one signal wiring selected by the first switching circuit to another signal wiring different from the one signal wiring, before measuring the signal of the other signal wiring,
In another block different from the one block
The drive detection circuit according to claim 3 or 4, wherein the signal of one signal wiring selected by the first switching circuit is measured one or more times.
The control circuit
A first process of applying an on-voltage to the drive circuit to one scanning wiring selected from the plurality of scanning wirings,
After applying the on-voltage, wait for a certain period of time,
In one block selected by the second switching circuit, the signal of one signal wiring selected by the first switching circuit is read out through the AD converter, and the first switching of the one block is performed. After selecting another signal line different from the one signal wiring by the circuit, and before reading the signal of the other signal wiring of the one block, at least by the second switching circuit, the one block Has a repetition of a procedure of selecting a different other block, a procedure of reading a signal of the other block, and a procedure of switching the first switching circuit of the other block, and the selection is performed by these processes. A second process of sequentially reading the signals of the sensor unit for one line corresponding to one scanning wiring, and
It is possible to execute the third process of applying an off voltage to the selected scanning wiring to the drive circuit after the completion of the second process.
The drive detection according to claim 5, wherein all the signals of the sensor unit are read out by repeating the first process, the standby, the second process, and the third process for all the scanning wirings. circuit.
The time of waiting, the a (M 2 -1) times the length of the AD converter reading time, driving detection circuit according to claim 6.
Further, it has M reference signal wirings which are provided in parallel with each of the M signal wirings and are not affected by the external stimulus of the sensor unit.
The reference signal lines of the M is divided into M 2 pairs of the blocks one by one M,
In each of the two M blocks,
A third switching circuit M 1 present in the reference signal line is connected to the input,
The load resistance and reference voltage detection amplifier connected to the output of the third switching circuit,
A differential amplifier circuit is provided,
The output of the voltage detection amplifier is connected to the + input of the differential amplifier circuit,
The signal detection circuit according to claim 1 or 2, wherein the output of the reference voltage detection amplifier is connected to the-input of the differential amplifier circuit.
The signal detection circuit, a control circuit, and a drive circuit according to claim 8 are provided.
The drive circuit is a circuit that applies an on voltage or an off voltage to the scanning wiring.
A drive detection circuit in which the first switching circuit, the third switching circuit, the second switching circuit, the AD converter, and the drive circuit are controlled by the control circuit.
The control circuit
In any one of the M 2 pieces of the blocks,
The one signal wiring selected by the first switching circuit and the reference signal wiring corresponding to the one signal wiring are different from the one signal wiring and the reference signal wiring corresponding to the one signal wiring. After switching to the other signal wiring and other reference signal wiring corresponding to the other signal wiring, and before measuring the signal difference between the other signal wiring and the other reference signal wiring,
In another block different from the one block
The drive detection circuit according to claim 9, wherein the signal difference between the one signal wiring selected by the first switching circuit and the reference signal wiring corresponding to the one signal wiring is measured one or more times.
The control circuit
A first process of applying an on-voltage to the drive circuit to one scanning wiring selected from the plurality of scanning wirings,
After applying the on-voltage, wait for a certain period of time,
In one block selected by the second switching circuit, the signal difference between one signal wiring selected by the first and third switching circuits and the reference signal wiring corresponding to the one signal wiring is obtained. Read through the AD converter, and the first switching circuit and the third switching circuit of the one block allow the one signal wiring and another signal wiring different from the reference signal wiring corresponding to the one signal wiring. After selecting the reference signal wiring corresponding to the signal line, at least the signal difference of the other block is set before reading the signal difference between the other signal wiring of the one block and the other reference signal wiring. The procedure of reading, the procedure of switching the second switching circuit 102, and the procedure of switching the first and third switching circuits of the other block are repeated, and the selected 1 is obtained by these processes. The second process of reading out the signal difference of the sensor unit for one line corresponding to the scanning wiring of the book in order, and
It is possible to execute the third process of applying an off voltage to the selected scanning wiring to the drive circuit after the completion of the second process.
The drive detection according to claim 10, wherein signals of all the sensor units are read out by repeating the first process, the standby, the second process, and the third process for all the scanning wirings. circuit.
With multiple signal wiring
Multiple scanning wires that intersect the signal wires,
A plurality of pixel portions including a pixel electrode, a first thin film transistor, and a second thin film transistor, which are provided corresponding to each of the intersections of the signal wiring and the scanning wiring,
Drain wiring for supplying power to the drain electrode of the first thin film transistor,
The sensor unit connected to the pixel electrode and
It is provided with a common electrode connected to the sensor unit.
The pixel electrode is connected to the gate electrode of the first thin film transistor, the drain electrode of the first thin film transistor is connected to the drain wiring, and the source electrode of the first thin film transistor is connected to the drain electrode of the second thin film transistor. A sensor array in which the gate electrode of the second thin film transistor is connected to the scanning wiring and the source electrode of the second thin film transistor is connected to the signal wiring.
The pixel portion further includes a third thin film transistor.
The sensor array has a common wiring for supplying power to the source electrode of the third thin film transistor and a reset wiring for supplying power to the gate electrode of the third thin film transistor.
12. The drain electrode of the third thin film transistor is connected to the pixel electrode, the source electrode of the third thin film transistor is connected to the common wiring, and the gate electrode of the third thin film transistor is connected to the reset wiring. Sensor array.
The pixel portion further includes a fourth thin film transistor and a fifth thin film transistor.
The sensor array has a plurality of reference signal wirings parallel to the signal wiring and common wiring for supplying power to the gate electrode of the fourth thin film transistor.
The gate electrode of the fourth thin film transistor is connected to the common wiring, the drain electrode of the fourth thin film transistor is connected to the drain wiring, and the source electrode of the fourth thin film transistor is connected to the drain electrode of the fifth thin film transistor. The sensor array according to claim 12 or 13, wherein the gate electrode of the fifth thin film transistor is connected to the scanning wiring, and the source electrode of the fifth thin film transistor is connected to the reference signal wiring.
The sensor array according to any one of claims 12 to 14, wherein the sensor unit is an organic piezoelectric material.
The first to fifth thin film transistors are provided on an insulating substrate, have a gate electrode, a gate insulating film, a semiconductor, a source electrode, and a drain electrode, and are laminated on the first to fifth thin film transistors. It has an insulating film, the pixel electrode is provided on at least the interlayer insulating film on the first thin film transistor, and the insulating substrate, the gate insulating film, and the interlayer insulating film are mainly composed of an organic insulating material. The sensor array according to claim 15.
The sensor array according to claim 16, wherein the pixel electrode is a mixture of conductive particles and an organic binder.
It ’s a sensor system,
With the sensor array
Equipped with a signal detection circuit
The sensor array is
With multiple signal wiring
Multiple scanning wires that intersect the signal wires,
A plurality of pixel portions including a pixel electrode, a first thin film transistor, and a second thin film transistor, which are provided corresponding to each of the intersections of the signal wiring and the scanning wiring,
Drain wiring for supplying power to the drain electrode of the first thin film transistor,
The sensor unit connected to the pixel electrode and
It is provided with a common electrode connected to the sensor unit.
The pixel electrode is connected to the gate electrode of the first thin film transistor, the drain electrode of the first thin film transistor is connected to the drain wiring, and the source electrode of the first thin film transistor is connected to the drain electrode of the second thin film transistor. The gate electrode of the second thin film transistor is connected to the scanning wiring, and the source electrode of the second thin film transistor is connected to the signal wiring.
The signal detection circuit
The plurality of signal wirings are divided into M 2 blocks, M 1 each.
In each of the two M blocks,
A first switching circuit M 1 present in the signal line is connected to the input,
A load resistor and a voltage detection amplifier connected to the output of the first switching circuit are provided.
M A second switching circuit in which each output from the two blocks is connected to an input,
A sensor system having an AD converter connected to the output of the second switching circuit.