Sensor and sensor system

Abstract

To use a plurality of photoelectric conversion elements in combination.SOLUTION: A sensor disclosed comprises a first photoelectric conversion element having photoelectric conversion characteristics that change in response to applied mechanical energy, and a second photoelectric conversion element having photoelectric conversion characteristics that change in response to applied mechanical energy, to which substantially no mechanical energy is applied or to which the applied mechanical energy is smaller than that of the first photoelectric conversion element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to sensors and sensor systems. [Background technology]

[0002] Patent Document 1 discloses a strain gauge that uses a photoelectric conversion element having a piezoelectric semiconductor. The photoelectromotive force output by the photoelectric conversion element having a piezoelectric semiconductor changes in response to strain applied to the photoelectric conversion element. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-154738 Summary of the Invention

[0004] The present inventors came up with the idea that the function of a sensor can be improved by using a plurality of photoelectric conversion elements having photoelectric conversion characteristics that change in response to applied mechanical energy.

[0005] An aspect of the present disclosure is a sensor. In one embodiment, the disclosed sensor may include a first photoelectric conversion element having a photoelectric conversion characteristic that changes in response to applied mechanical energy, and a second photoelectric conversion element having a photoelectric conversion characteristic that changes in response to applied mechanical energy, to which substantially no mechanical energy is applied or to which the mechanical energy applied is smaller than that of the first photoelectric conversion element.

[0006] In one embodiment, the disclosed sensor may include a flexible first base, a second base having higher rigidity than the first base, a first photoelectric conversion element provided on the first base and having photoelectric conversion characteristics that change in response to applied mechanical energy, and a second photoelectric conversion element provided on the second base and having photoelectric conversion characteristics that change in response to applied mechanical energy.

[0007] An aspect of the present disclosure is a sensor system. In an embodiment, the disclosed sensor system may include a sensor and a signal processing circuit connected to the sensor.

[0008] Further details will be described in the following embodiments. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a configuration diagram of the sensor system. [Figure 2] FIG. 2 is a diagram showing the configuration of the sensor. [Figure 3] FIG. 3 is a diagram illustrating the energy levels of a photoelectric conversion element. [Figure 4] FIG. 4 is a configuration diagram of the sensor system. [Figure 5] FIG. 5 is a configuration diagram of the sensor. [Figure 6] Figure 6 shows the strain, temperature change, and illuminance characteristics of the photoelectric conversion element. [Figure 7] FIG. 7 is a configuration diagram of the signal processing circuit. [Figure 8] FIG. 8 is a block diagram showing the processing of the processor. DETAILED DESCRIPTION OF THE INVENTION

[0010] <1. Overview of sensors and sensor systems>

[0011] (1) The sensor according to the embodiment may include a first photoelectric conversion element having photoelectric conversion characteristics that change in response to applied mechanical energy, and a second photoelectric conversion element having photoelectric conversion characteristics that change in response to applied mechanical energy, to which substantially no mechanical energy is applied or to which the applied mechanical energy is smaller than that of the first photoelectric conversion element.

[0012] (2) The sensor may further include a third photoelectric conversion element to which substantially no mechanical energy is applied together with the second photoelectric conversion element, or to which the mechanical energy applied is substantially the same as that applied to the second photoelectric conversion element.

[0013] (3) The sensor according to the embodiment may include a flexible first base, a second base having higher rigidity than the first base, a first photoelectric conversion element provided on the first base and having photoelectric conversion characteristics that change in response to applied mechanical energy, and a second photoelectric conversion element provided on the second base and having photoelectric conversion characteristics that change in response to applied mechanical energy.

[0014] (4) The sensor may further include a third photoelectric conversion element provided on the second base and having a photoelectric conversion characteristic that changes in response to applied mechanical energy.

[0015] (5) A sensor system according to the embodiment may include the sensor according to any one of (1) to (4) above, and a signal processing circuit connected to the sensor.

[0016] The signal processing circuit may calibrate the first output signal of the first photoelectric conversion element using the second output signal of the second photoelectric conversion element.

[0017] (6) A sensor system according to an embodiment includes a sensor according to (2) or (4) and a signal processing circuit connected to the sensor, and the signal processing circuit can output thermal response data based on either the second output signal of the second photoelectric conversion element or the third output signal of the third photoelectric conversion element, and can output optical response data based on the other output signal.

[0018] (7) A sensor system according to an embodiment includes a sensor according to (2) or (4) and a signal processing circuit connected to the sensor, and the signal processing circuit can calibrate the first output signal of the first photoelectric conversion element using the second output signal of the second photoelectric conversion element and the third output signal of the third photoelectric conversion element.

[0019] (8) A sensor system according to an embodiment includes a sensor according to (2) or (4) and a signal processing circuit connected to the sensor, and the signal processing circuit can calibrate the output voltage of either the second photoelectric conversion element or the third photoelectric conversion element using the output current value of the other element.

[0020] (9) A sensor system according to an embodiment includes a sensor according to (2) or (4) and a signal processing circuit connected to the sensor, and the signal processing circuit may be configured to operate using one or both of the first photovoltaic power generated by the first photoelectric conversion element and the second photovoltaic power generated by the second photoelectric conversion element as operating power.

[0021] (10) A sensor system according to an embodiment includes a sensor according to (2) or (4) and a signal processing circuit connected to the sensor, and the signal processing circuit can be configured to operate using at least one of a first photovoltaic power generated by the first photoelectric conversion element, a second photovoltaic power generated by the second photoelectric conversion element, and a third photovoltaic power generated by the third photoelectric conversion element as its operating power.

[0022] <2. Examples of sensors and sensor systems>

[0023] Hereinafter, an example of a sensor and a sensor system according to an embodiment will be described with reference to the drawings.

[0024] The sensor system 1 shown in FIG. 1 includes a sensor 100 and a signal processing circuit 200 (signal processing device 200). The sensor 100 outputs a photovoltaic power in response to an input such as strain. The sensor 100 according to the embodiment can be used as a mechanical quantity sensor. Mechanical quantities that can be detected by the sensor 100 include, for example, force, acceleration, or vibration. As will be described later, the sensor 100 according to the embodiment can also detect light and / or heat in addition to mechanical quantities.

[0025] The signal processing circuit 200 is connected to the sensor 100 and performs signal processing and the like on the output signal of the sensor 100. The signal processing circuit 200 performs signal processing on the output signal of the sensor 100 (e.g., a voltage signal or a current signal) and can output data indicating a detected mechanical quantity. In addition to being able to output data indicating a mechanical quantity, the signal processing circuit 200 can also output data indicating light intensity (illuminance) and / or data indicating temperature from the output signal of the sensor 100. As an example, the signal processing circuit 200 can operate as a data logger of physical quantity data detected by the sensor 100, as described below.

[0026] The signal processing circuit 200 included in the sensor system 1 can transmit data such as data indicating mechanical quantities to the external device 300 via wireless communication or wired communication. The external device 300 can receive data from the signal processing circuit 200. The external device 300 can be configured by, for example, a computer. The external device 300 can process the received data and perform monitoring processing on a monitored object such as a device or structure in which the sensor 100 is installed.

[0027] 1 and 2, the sensor 100 includes a plurality of photoelectric conversion elements 110 and 120. The sensor 100 shown in Fig. 1 and 2 includes, as an example, two photoelectric conversion elements, a first photoelectric conversion element 110 and a second photoelectric conversion element 120. The plurality of photoelectric conversion elements 110 and 120 may have the same structure.

[0028] Each of the multiple photoelectric conversion elements 110, 120 has photoelectric conversion characteristics that change depending on the applied mechanical energy. The mechanical energy is, for example, strain, force, acceleration, or vibration energy acting on the photoelectric conversion elements 110, 120. The photoelectric conversion elements 110, 120 may be configured as heterojunction photoelectric conversion elements. The photoelectric conversion elements 110, 120 may be configured as PN junction semiconductor elements including N-type semiconductors 11A, 11B and P-type semiconductors 12A, 12B.

[0029] In the photoelectric conversion elements 110 and 120, whose photoelectric conversion characteristics change in response to applied mechanical energy, at least one of the pn-junctioned n-type semiconductors 11A and 11B and p-type semiconductors 12A and 12B is a piezoelectric semiconductor. For example, in the photoelectric conversion elements 110 and 120, the n-type semiconductors 11A and 11B are piezoelectric semiconductors. The n-type piezoelectric semiconductors 11A and 11B are, for example, ZnO. For example, the p-type semiconductors 12A and 12B are non-piezoelectric semiconductors. The p-type semiconductors 12A and 12B are, for example, selenium (Se). Selenium has a high optical absorption coefficient for visible light. This improves the photoelectric conversion efficiency of the photoelectric conversion elements 110 and 120. The conduction band minimum and band gap can be adjusted by adding approximately 0 to 10% magnesium (Mg) to ZnO. Regarding selenium (Se), tellurium (Te) may be vapor-deposited on ZnO before selenium is vapor-deposited to strengthen adhesion with the ZnO layer. In this case, the amount of tellurium used may be extremely small (film thickness of 1 nm or less).

[0030] Fig. 3 is a diagram for explaining the energy levels of the photoelectric conversion elements 110 and 120. Fig. 3(A) shows the energy levels when no mechanical energy such as tensile strain or compressive strain is applied to the photoelectric conversion elements 110 and 120, and Fig. 3(B) shows the energy levels when mechanical energy is applied.

[0031] As shown in Figure 3, at the PN junction (boundary) of the first photoelectric conversion element 110, a band offset ΔEc occurs, which is the energy level difference between the piezoelectric semiconductor ZnO (N-type semiconductor 11) and selenium (Se) (P-type semiconductors 12A, 12B).

[0032] When strain is applied, polarization occurs within the N layer, which is a piezoelectric semiconductor. When polarization occurs within the N layer, negative polarization charge increases at the PN junction. When negative polarization charge increases at the PN junction, electrons (negative) in the conduction band repel and holes in the valence band are attracted, generating piezoelectric polarization charge. This reduces the band offset ΔEc at the PN junction, as shown in Figure 4(B) "After Change." As a result, the open-circuit voltage and short-circuit current when exposed to light between electrodes 21 and 22 change according to the strain. For example, as the strain increases, the open-circuit voltage increases. In other words, as the strain increases, the photovoltaic power increases.

[0033] 1 and 2, first electrodes 21A and 21B are connected to the N-type semiconductors 11A and 11B. Second electrodes 22A and 22B are connected to the P-type semiconductors 12A and 12B. The first electrodes 21A and 21B are, for example, transparent electrodes (light-transmitting electrodes). The transparent electrodes are, for example, ITO (Indium-Tin Oxide) electrodes. The second electrodes 22A and 22B may be non-light-transmitting electrodes, for example, gold (Au) electrodes.

[0034] The multiple photoelectric conversion elements 110, 120 can be provided on the base 23. As an example, the first electrodes 21A, 21B are arranged on the base 23, and the N-type semiconductors 11A, 11B, the P-type semiconductors 12A, 12B, and the second electrodes 22A, 22B are stacked in this order on the first electrodes 21A, 21B.

[0035] The base 23 is made of a transparent material (light-transmitting material). For example, the material forming the base 23 is PET (polyethylene terephthalate) or a polyimide film. As shown in FIGS. 1 and 2, for example, light L irradiated onto the sensor 100 is irradiated from below the base 23 toward the base 23 in FIGS. 1 and 2. The light L passes through the light-transmitting base 23 and the transparent electrodes 21A and 21B to reach the photoelectric conversion elements 110 and 120.

[0036] Photovoltaic power is generated between electrodes 21A, 21B and electrodes 22A, 22B due to photoelectric conversion by photoelectric conversion elements 110, 120. That is, a voltage is generated between electrodes 21A, 21B and electrodes 22A, 22B, and a current flows between electrodes 21A, 21B and electrodes 22A, 22B.

[0037] The electrodes 21A and 22A provided on the first photoelectric conversion element 110 are connected to a signal processing circuit 200. The electrodes 21A and 22A provided on the first photoelectric conversion element 110 are connected to a first channel input terminal 201 of the signal processing circuit 200, for example. A voltage (open circuit voltage) generated by the first photoelectric conversion element 110 is provided to the first channel input terminal 201 as a first output signal of the sensor 100.

[0038] The electrodes 21B and 22B provided on the second photoelectric conversion element 120 are connected to the signal processing circuit 200. The electrodes 21B and 22B provided on the second photoelectric conversion element 120 are connected to a second channel input terminal 202 of the signal processing circuit 200, for example. A voltage (open circuit voltage) generated by the second photoelectric conversion element 120 is provided to the second channel input terminal 202 as a second output signal of the sensor 100.

[0039] As shown in FIGS. 1 and 2, the base 23 includes a first base 23A and a second base 23B. In FIGS. 1 and 2, the first base 23A and the second base 23B are integrally formed from the same material, as an example. The first base 23A is relatively thin and easily elastically deforms. Therefore, the first base 23A is easily deformed by mechanical action such as strain or vibration. In this embodiment, the first base 23A is used as a detection region for mechanical energy.

[0040] The second base 23B is relatively thicker than the first base 23A. Therefore, the second base 23B has higher rigidity than the first base 23A and is less susceptible to elastic deformation. The second base 23B preferably has high rigidity so that it does not substantially deform under normal usage conditions. The second base 23B is less susceptible to deformation even when subjected to mechanical action such as strain or vibration. In the embodiment, the second base 23B is used, for example, as a non-detection region for mechanical energy, and is used as a detection region for light and / or heat, as described below.

[0041] 1 and 2, the rigidity of the first base 23A and the second base 23B is made different by making the thickness of the base 23 different, but the rigidity of the first base 23A and the second base 23B may also be made different by making the materials constituting the first base 23A and the second base 23B different. Also, the first base 23A and the second base 23B do not need to be integral and may be separate.

[0042] The first photoelectric conversion element 110 is provided on the first base 23A (a detection area for mechanical energy) which is easily deformed. Therefore, mechanical energy is applied to the first photoelectric conversion element 110 due to distortion or vibration occurring in the first base 23A.

[0043] On the other hand, the second photoelectric conversion element 120 is provided on the second base 23B (a region where mechanical energy is not detected), which is difficult to deform. Therefore, mechanical energy due to distortion or the like is not substantially applied to the second photoelectric conversion element 120. Furthermore, even if mechanical energy is applied to the second photoelectric conversion element 120, the mechanical energy applied to the second photoelectric conversion element 120 is smaller than the mechanical energy applied to the first photoelectric conversion element 110.

[0044] Here, the light L is irradiated to both the first photoelectric conversion element 110 and the second photoelectric conversion element 120 in the same manner. That is, the illuminance of the light L irradiated to the first photoelectric conversion element 110 and the second photoelectric conversion element 120 is substantially the same. Furthermore, the first photoelectric conversion element 110 and the second photoelectric conversion element 120 are used in environments of substantially the same temperature T.

[0045] The photoelectric conversion characteristics of the first photoelectric conversion element 110 change depending on the magnitude of the applied mechanical energy. Therefore, the first output signal of the first photoelectric conversion element 110 provided on the easily deformable first base 23A is a signal corresponding to the magnitude of the applied mechanical energy. In other words, the first output signal of the first photoelectric conversion element 110 is a signal of mechanical response. Therefore, the mechanical response is input as the first output signal to the first channel input terminal 201 of the signal processing circuit 200.

[0046] The photoelectric conversion characteristics of the second photoelectric conversion element 120 also change depending on the magnitude of the applied mechanical energy. However, even when mechanical energy due to strain or the like is applied to the first photoelectric conversion element 110, substantially no mechanical energy is applied to the second photoelectric conversion element 120. Therefore, the second output signal of the second photoelectric conversion element 120 is a non-mechanical response based on the illuminance of light or the like. Therefore, the non-mechanical response is input as the second output signal to the second channel input terminal 202 of the signal processing circuit 200.

[0047] Furthermore, even if mechanical energy is applied to the second photoelectric conversion element 120, the applied mechanical energy is smaller than that applied to the first photoelectric conversion element 110. Therefore, the second output signal of the second photoelectric conversion element 120 is less affected by the mechanical energy than the first output signal. In this way, the first output signal and the second output signal are affected differently by the mechanical energy.

[0048] Figures 4 and 5 show another example of the sensor system 1. Regarding the sensor system 1 shown in Figures 4 and 5, the points not particularly described below are the same as those of the sensor system 1 shown in Figures 1 and 2.

[0049] 4 and 5, the sensor 100 included in the sensor system 1 includes a first photoelectric conversion element 110, a second photoelectric conversion element 120, and a third photoelectric conversion element 130. That is, the sensor 100 in FIGS. 4 and 5 includes three photoelectric conversion elements 110, 120, and 130. The three photoelectric conversion elements 110, 120, and 130 may have the same structure. That is, like the first photoelectric conversion element 110 and the second photoelectric conversion element 120, the third photoelectric conversion element 130 has an N-type semiconductor 11C and a P-type semiconductor 12 disposed between electrodes 21C and 22C, and has photoelectric conversion characteristics that change depending on the magnitude of applied mechanical energy.

[0050] Similar to the second photoelectric conversion element 120, the third photoelectric conversion element 130 is provided on the second base 23B, which is difficult to deform. Therefore, similar to the second photoelectric conversion element, the third photoelectric conversion element 130 is not substantially subjected to mechanical energy. Alternatively, even if mechanical energy is applied, the mechanical energy is substantially the same as the mechanical energy applied to the second photoelectric conversion element 120. In other words, the mechanical energy applied to the third photoelectric conversion element 130 is smaller than the mechanical energy applied to the first photoelectric conversion element 110.

[0051] Here, the light L is irradiated in the same manner to all of the first photoelectric conversion element 110, the second photoelectric conversion element 120, and the third photoelectric conversion element 130. That is, the illuminance of the light L irradiated to each of the photoelectric conversion elements 110, 120, and 130 is substantially the same. Furthermore, each of the photoelectric conversion elements 110, 120, and 130 is used in an environment of substantially the same temperature T.

[0052] The electrodes 21C and 22C provided on the third photoelectric conversion element 130 are connected to the signal processing circuit 200. The electrodes 21C and 22C provided on the third photoelectric conversion element 130 are connected, for example, to a third channel input terminal 203 of the signal processing circuit 200. A signal generated by the third photoelectric conversion element 130 is provided to the third channel input terminal 203 as a third output signal of the sensor 100.

[0053] The sensor 100 shown in FIG. 4 includes a current-voltage converter 141 connected to the electrode 21C of the third photoelectric conversion element 130. For example, a current-voltage conversion amplifier (I / V amplifier) ​​is used as the current-voltage converter 141. The current (photocurrent) generated by the third photoelectric conversion element 130 is converted into a voltage by the current-voltage converter 141. A voltage value corresponding to the current value generated by the third photoelectric conversion element 130 is provided as a third output signal to the third channel input terminal 203. Note that the signal processing circuit 200 may also include the current-voltage converter 141. In this case, the current generated by the third photoelectric conversion element 130 is provided to the third channel input terminal 203.

[0054] In the sensor 100 shown in FIG. 4, the first photoelectric conversion element 110 is for obtaining a mechanical response (strain response), the second photoelectric conversion element 120 is for obtaining a thermal response, and the third photoelectric conversion element 130 is for obtaining an optical response.

[0055] Figure 6 shows the open-circuit voltage V of the photoelectric conversion elements 110, 120, and 130 as a function of strain and temperature changes. OC and the short-circuit current J of the photoelectric conversion elements 110, 120, and 130 relative to the illuminance. SC This shows the relationship between

[0056] As shown in Figure 6(A), as the strain ε increases, the open-circuit voltage V OC Therefore, the first output signal (open circuit voltage) of the first photoelectric conversion element 110 increases as the strain ε increases. Therefore, the signal processing circuit 200 can obtain data indicating the strain ε based on the first output signal of the first photoelectric conversion element 110.

[0057] As shown in Figure 6(B), when the temperature change ΔT increases, the open-circuit voltage V OC becomes smaller. That is, the photoelectric conversion characteristics of the photoelectric conversion elements 110, 120, and 130 are also affected by the temperature T. Therefore, in an environment where the illuminance of light is constant and mechanical energy is not applied or is constant, the second output signal (open circuit voltage) of the second photoelectric conversion element 120 becomes larger as the temperature change ΔT becomes larger. Therefore, the signal processing circuit 200 can obtain data indicating the temperature T based on the second output signal of the second photoelectric conversion element 120.

[0058] Furthermore, the second output signal of the second photoelectric conversion element 120 can be used to calibrate the first output signal (mechanical response such as strain) in addition to being used as a measurement value of the temperature T. The environments in which the first photoelectric conversion element 110 and the second photoelectric conversion element 120 exist are substantially the same except for the magnitude of the applied mechanical energy. Therefore, by using the second output signal of the second photoelectric conversion element 120, it is possible to determine the mechanical energy (e.g., the magnitude of strain) applied to the first photoelectric conversion element 110 while eliminating the influence of environmental factors other than the mechanical energy.

[0059] As shown in FIG. 6C, when the illuminance P of the light L increases, the short-circuit current J of the photoelectric conversion elements 110, 120, and 130 SC Therefore, in an environment where no mechanical energy is applied or the applied mechanical energy is constant (temperature is also constant), the output current of the third photoelectric conversion element 130 increases as the illuminance P increases. Therefore, the signal processing circuit 200 can obtain data indicating the illuminance P based on the third output signal of the third photoelectric conversion element 130.

[0060] Furthermore, the third output signal of the third photoelectric conversion element 130 can be used not only as a measurement value of the illuminance P, but also for calibrating the first output signal (mechanical response such as strain) and / or calibrating the second output signal (thermal response) (light illuminance calibration), as will be described later.

[0061] Fig. 7 shows an example of the signal processing circuit 200 shown in Fig. 4. Note that the signal processing circuit 200 shown in Fig. 7 can also be used as the signal processing circuit shown in Fig. 1 if the third channel input terminal 203 is not used.

[0062] 7 includes a processor 211 for signal processing and a memory 212. The processor 211 may be, for example, a CPU that executes a computer program (software) stored in the memory 212, or may be configured by a hardware circuit that performs signal processing using analog circuits and / or logic circuits. The memory 212 can store data obtained by signal processing. Therefore, the signal processing circuit 200 can be used as a data logger.

[0063] The signal processing circuit 200 may include a communication device 213 that performs data communication with the external device 300. The communication device 213 can transmit data obtained by signal processing to the external device 300.

[0064] The signal processing circuit 200 shown in FIG. 7 includes a power supply circuit 220. The power supply circuit 220 generates operating power for the other components 211, 212, and 213 of the signal processing circuit 200 from the output (photovoltaic power) of the sensor 100. The signal processing circuit 200 can operate by receiving power from the photovoltaic power of the sensor 100, and therefore can operate without being connected to a battery or supplied with power from an external power source. The sensor 100 may also include the power supply circuit 220 shown in FIG. 7. In this case, it becomes possible for the circuits included in the sensor 100 (such as the current-voltage converter 141) to be self-powered.

[0065] 7 is connected to all three input terminals 201, 202, and 203, and is therefore able to generate operating power from the photovoltaic power of all three photoelectric conversion elements 110, 120, and 130. However, the power supply circuit 220 may generate operating power from any one or any two of the three photoelectric conversion elements 110, 120, and 130. For example, the power supply circuit 220 may generate operating power from both the first photoelectric conversion element 110 and the second photoelectric conversion element 120, or may generate operating power from both the second photoelectric conversion element 120 and the third photoelectric conversion element 130.

[0066] FIG. 8 shows an example of signal processing 231, 232, and 233 performed by the processor 211.

[0067] Among the signal processing steps 231, 232, and 233 shown in FIG. 8, the first processing step 231 is a calibration processing step. The calibration processing step 231 is a processing step for calibrating the first output signal of the first photoelectric conversion element 110 for detecting distortion using the second output signal of the second photoelectric conversion element 120, which is substantially unaffected by distortion. The calibration processing may, for example, simply calculate the difference between the first output signal and the second output signal, or may calibrate the first output signal by performing other calculations using the first output signal and the second output signal. The other calculations may, for example, calibrate the first output signal based on the value of the second output signal using a correction table or correction function that corrects the first output signal according to the value of the second output signal.

[0068] The calibration process 231 may be a process of calibrating the first output signal of the first photoelectric conversion element 110 for detecting strain using the second output signal of the second photoelectric conversion element 120 and the third output signal of the third photoelectric conversion element 120, which are substantially unaffected by strain. The calibration using the second output signal and the third output signal may, for example, calibrate the first output signal based on the value of the second output signal and the value of the third output signal using a correction table or a correction function that corrects the first output signal according to the second output signal (voltage value; mainly thermal response) and the third output signal (current value (corresponding voltage value); optical response).

[0069] The processor 211 can obtain mechanical quantity data (strain data, etc.) that is free from the influence of factors such as the magnitude of light illuminance through the calibration process 231.

[0070] Of the signal processes 231, 232, and 233 shown in Fig. 8, the second process 232 is a temperature calculation process. The temperature calculation process 232 is a process for obtaining temperature data (thermal response data) indicating the temperature T from the second output signal. As shown in Fig. 6(B), the voltage of the second photoelectric conversion element 120 is affected by the temperature T, so the processor 211 can perform an operation to obtain the temperature data based on the second output signal and output the temperature data.

[0071] The open-circuit voltage V of the photoelectric conversion element 120 OC varies mainly depending on the temperature T and has an approximately linear response to the temperature T. Therefore, the temperature data can be determined based only on the second output signal.

[0072] In the equation (1) of FIG. 8, A is the quality factor of the photoelectric conversion element 120, k is the Boltzmann coefficient, T is the temperature, q is the charge, X is the light collection magnification, and J SC is the short circuit current density, and J 00 is the dark current density.

[0073] The short-circuit current density J in equation (1) SC is affected by the illuminance of light, but in equation (1), the short-circuit current density J SC / dark current density J 00 The natural logarithm ln of this is the open circuit voltage V OC Therefore, the value of the open circuit voltage V OC Compared to the temperature T that affects the short circuit current density J SC is the open circuit voltage V OC Therefore, the open circuit voltage V OC The influence of light on the short-circuit current density J can be ignored. SC is a constant, so there is no need to consider the influence of light.

[0074] In order to more accurately determine the temperature T when the illuminance fluctuates, the third output signal (current value; light response) can be used to calibrate the second output signal to eliminate the influence of light, thereby obtaining temperature data from which the influence of light has been eliminated. The calibration of the second output signal may be performed, for example, by using a correction table or correction function that corrects the second output signal in accordance with the third output signal, which is the light response.

[0075] 8, the third process 233 is an illuminance calculation process. The illuminance calculation process 233 is a process for obtaining illuminance data (light response data) indicating the illuminance P from the third output signal. As shown in equation (2) in FIG. 8, the short-circuit current I ph is determined based on the illuminance P of the incident light L. Therefore, the processor 211 can perform a calculation to obtain illuminance data based on the third output signal and output the illuminance data.

[0076] Note that the calibration of the first output signal (mechanical quantity) based on the second output signal may be calibration of the first output signal using temperature data determined from the second output signal. Also, the calibration of the first output signal (mechanical quantity) based on the second and third output signals may be calibration of the first output signal using temperature data determined from the second output signal and illuminance data determined from the third output signal. Furthermore, the calibration of the second output signal (thermal response) based on the third output signal (light response) may be calibration of the second output signal (temperature) using illuminance data determined from the third output signal.

[0077] The present invention is not limited to the above-described embodiment, and various modifications are possible. [Explanation of symbols]

[0078] 1: Sensor system 11A: N-type semiconductor 11B: N-type semiconductor 11C: N-type semiconductor 12A: P-type semiconductor 12B: P-type semiconductor 12C: P-type semiconductor 21A: 1st electrode 21B: 1st electrode 21C: 1st electrode 22A: 2nd electrode 22B: 2nd electrode 22C: 2nd electrode 23: Bass 23A: First base 23B: Second base 100: Sensor 110: First photoelectric conversion element 120: Second photoelectric conversion element 130: Third photoelectric conversion element 141: Voltage converter 200: Signal processing circuit 201: Channel 1 input terminal 202: Second channel input terminal 203: Third channel input terminal 211: Processor 212: Memory 213: Communication equipment 220: Power supply circuit 231: Proofreading 232: Temperature calculation process 233: Illuminance calculation process 300: External device L: light P: illuminance T :Temperature

Claims

1. a first photoelectric conversion element having a photoelectric conversion characteristic that changes in response to applied mechanical energy; a second photoelectric conversion element having a photoelectric conversion characteristic that changes depending on the applied mechanical energy, to which substantially no mechanical energy is applied or to which the applied mechanical energy is smaller than that of the first photoelectric conversion element; A sensor comprising:

2. Further provided is a third photoelectric conversion element to which mechanical energy is not substantially applied together with the second photoelectric conversion element, or to which mechanical energy is applied that is substantially the same as that of the second photoelectric conversion element. The sensor of claim 1 .

3. a flexible first base; a second base having higher rigidity than the first base; Equipped with a first photoelectric conversion element provided on the first base and having a photoelectric conversion characteristic that changes in response to applied mechanical energy; a second photoelectric conversion element provided on the second base and having a photoelectric conversion characteristic that changes in response to applied mechanical energy; A sensor comprising:

4. a third photoelectric conversion element provided on the second base and having a photoelectric conversion characteristic that changes in response to applied mechanical energy; The sensor of claim 3 .

5. The sensor according to any one of claims 1 to 4; a signal processing circuit connected to the sensor; Equipped with the signal processing circuit calibrates the first output signal of the first photoelectric conversion element using the second output signal of the second photoelectric conversion element; Sensor system.

6. The sensor according to claim 2 or claim 4; a signal processing circuit connected to the sensor; Equipped with the signal processing circuit outputs thermal response data based on one of the second output signal of the second photoelectric conversion element and the third output signal of the third photoelectric conversion element, and outputs photoresponse data based on the other output signal. Sensor system.

7. The sensor according to claim 2 or claim 4; a signal processing circuit connected to the sensor; Equipped with the signal processing circuit calibrates the first output signal of the first photoelectric conversion element using the second output signal of the second photoelectric conversion element and the third output signal of the third photoelectric conversion element; Sensor system.

8. The sensor according to claim 2 or claim 4; a signal processing circuit connected to the sensor; Equipped with The signal processing circuit uses an output current value of either the second photoelectric conversion element or the third photoelectric conversion element to calibrate an output voltage of the other element. Sensor system.

9. The sensor according to any one of claims 1 to 4; a signal processing circuit connected to the sensor; Equipped with the signal processing circuit is configured to operate using one or both of a first photovoltaic power generated by the first photoelectric conversion element and a second photovoltaic power generated by the second photoelectric conversion element as operating power. Sensor system.

10. The sensor according to claim 2 or claim 4; a signal processing circuit connected to the sensor; Equipped with the signal processing circuit is configured to operate using at least one of a first photovoltaic power generated by the first photoelectric conversion element, a second photovoltaic power generated by the second photoelectric conversion element, and a third photovoltaic power generated by the third photoelectric conversion element as operating power. Sensor system.

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