JP7244069B2 - Inspection device and inspection method - Google Patents

Description

The present invention relates to an inspection apparatus and an inspection method.

In order to extract current from a solar cell, it is necessary to connect a connector to the solar cell. In the case of solar cells for artificial satellites, the solar cells and connectors are connected by resistance welding in order to ensure reliability. ing. A bypass diode is also connected to the solar cell to protect the solar cell. Since satellites have a long trial period and cannot be repaired once they go out into space, the reliability of solar cells is important. Therefore, it is necessary to confirm whether there is any problem in the performance of the solar cell after connector welding.

Patent Literature 1 describes a technique for inspecting defects in solar cells using an EL (electroluminescence) emission method inspection and a thermograph inspection. Further, Patent Literature 2 describes a technique for evaluating the performance of a solar cell by heating a solar cell element that constitutes a solar cell and detecting the light emission characteristics of light emitted from the solar cell element by heating.

WO2007/129585 JP 2013-098411 A

However, in the above-described related technology, EL inspection and IR (infrared) inspection need to be performed by separate inspection apparatuses, which takes time. In addition, there is a problem that the use of dedicated inspection equipment increases the space required for the inspection equipment, resulting in expensive equipment.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an inspection apparatus and an inspection method that can solve the above-described problems.

According to the first aspect of the present invention, the inspection device includes: a probe for contacting a connector of a solar cell to which a bypass diode is connected; a first power supply unit for supplying current in the forward direction, which is the direction opposite to the current flowing through the solar cell; , a first analysis unit that analyzes the first captured image; and a second power supply unit that applies current to the solar cell via the probe in a direction opposite to the direction of the current generated by the solar cell; a second imaging unit that captures a second captured image showing the temperature of the solar cell when the current is passed in the opposite direction; and a second analysis unit that analyzes the second captured image, the probe and It is characterized in that switching is made between the first power supply section and the second power supply section in a state in which the connector is in contact with the connector .

According to a second aspect of the present invention, an inspection method includes: a probe for contacting a connector of a solar cell to which a bypass diode is connected; A current is passed in the forward direction, which is the direction opposite to the current flowing through, and a first captured image showing the light emitting state of the solar cell when the current is passed in the forward direction is captured, and the first captured image is analyzed, A second image showing the temperature of the solar cell when current is passed through the solar cell through the probe in the opposite direction, which is the same direction as the current generated by the solar cell, and the current is caused to flow in the opposite direction. An image is captured, the second captured image is analyzed, and the direction of current flow is switched in a state in which the probe and the connector are in contact with each other .

According to the present invention, both EL inspection and IR inspection can be performed with one inspection apparatus.

It is a figure showing composition of an inspection device by one embodiment of the present invention. It is a figure which shows the hardware constitutions of the analysis apparatus by one Embodiment of this invention. 1 is a functional block diagram of an analysis device according to one embodiment of the present invention; FIG. It is a figure which shows the processing flow of the inspection apparatus by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 1st process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 2nd process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 3rd process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 4th process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 5th process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 6th process of the test|inspection by one Embodiment of this invention. It is a figure which shows the state of the test|inspection apparatus in the 7th process of the test|inspection by one Embodiment of this invention. It is a figure showing the minimum composition of an inspection device by one embodiment of the present invention.

An inspection apparatus and an inspection method according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing the configuration of an inspection apparatus according to this embodiment.
The inspection device 1 is a device for inspecting the solar cell 20 . A connector 21 is connected to the solar cell 20 for extracting current from the solar cell 20 . In addition, a bypass diode is connected to the solar cell 20 in order to prevent a failure from occurring due to a reverse current flow in the solar cell 20 . A bypass diode is a circuit for allowing current generated in the reverse direction of the solar cell 20 to flow. That is, the solar cell 20 and the bypass diode are connected so that the anode and cathode (positive and negative electrodes) directions are reversed. The connector 21 is connected to the solar cell 20 and the bypass diode by a parallel gap welding method.

The inspection apparatus 1 welds the connector 21 to the solar cell 20 to which the bypass diode is connected, and then inspects the assembly to which the cover glass is attached. The inspection device 1 determines the conductivity of the solar cell 20 (that is, the quality of the connection between the solar cell 20 and the connector 21) by EL inspection. Also, the inspection device 1 determines whether the bypass diode functions normally (that is, whether the connection between the solar cell 20 and the bypass diode is good or bad) by IR inspection.

The inspection device 1 includes a Y-axis 13, a metal plate 14, an X-axis 15, a Z-axis 16, a measurement unit 18, a power supply 19, an axis control controller 22, a PLC 23 (PLC: Programmable Logic Controller), an analysis device 24, a switch 25, and the like. Configured.

As shown, the inspection apparatus 1 has a Y-axis 13, an X-axis 15, and a Z-axis 16 that are orthogonal to each other. A metal plate 14 movable along the Y-axis 13 is installed on the Y-axis 13 . The metal plate 14 is a stage on which the solar cell 20 to be inspected is installed. The metal plate 14 is metallic without surface treatment. The metal plate 14 is connected to a power supply 19 through wiring. Metal plate 14 functions as a contact for energizing solar cell 20 . An insulator such as resin is provided between the metal plate 14 and the connector 21 so that the metal plate 14 and the connector 21 are not electrically connected.

The X-axis 15 and Z-axis 16 are installed above the metal plate 14 . A measurement unit 18 having a CCD camera 11 (CCD: Charge-Coupled Device), an IR camera 12 (IR: InfraRed), and a probe 17 is installed on the Z-axis 16 . Measuring unit 18 is movable along X-axis 15 and Z-axis 16 .

The probe 17 is a metallic probe. The probe 17 is connected to a power supply 19 through wiring. The probe 17 functions as a contact for energizing the solar cell 20 . When the probe 17 automatically contacts the connector 21 of the solar cell 20 placed on the metal plate 14 during the inspection, the probe 17, the connector 21, the solar cell 20 and the metal plate 14 are electrically connected. .

The power supply 19 includes a first power supply section 19-1 and a second power supply section 19-2. The first power supply section 19-1 and the second power supply section 19-2 are electrically connected to the solar cell 20 installed on the metal plate 14 through the metal plate 14 and the probe 17. FIG. The first power supply section 19-1 is a power supply for EL inspection. The first power supply section 19-1 is connected to the metal plate 14 and the probe 17 so as to energize the assembly in the direction opposite to the current generated by the solar cell 20 (hereinafter referred to as "forward direction"). In other words, the first power supply section 19-1 supplies current in the direction in which the solar cell 20 is energized. The second power supply section 19-2 is a power supply for IR inspection. The second power supply section 19-2 is connected to the metal plate 14 and the probe 17 so as to energize the assembly in the same direction as the current generated by the solar cell 20 (hereinafter referred to as "opposite direction"). That is, the second power supply section 19-2 supplies current in a direction that energizes the bypass diode connected to the solar cell 20. FIG.

The CCD camera 11 and the IR camera 12 image the metal plate 14 from above. The CCD camera 11 is a first imaging unit that captures a first captured image showing the light emitting state of the solar cell 20 when current is passed in the forward direction. The IR camera 12 is a second imaging unit that captures a second captured image showing the temperature of the solar cell 20 when the current is passed in the opposite direction. The second picked-up image is a thermographic image that indicates the temperature in terms of brightness and hue.

A switch 25 is a switch for turning on or off the inspection apparatus 1 . Axis control controller 22 controls movement of metal plate 14 and measurement unit 18 . The PLC 23 is a control device that controls the inspection device 1 in an integrated manner. The PLC 23 is connected to the CCD camera 11, the IR camera 12, the power supply 19, the axis controller 22 and the analysis device 24. PLC 23 controls axis controller 22, power supply 19, CCD camera 11, and IR camera 12, respectively. Also, the PLC 23 transmits the first captured image captured by the CCD camera 11 and the second captured image captured by the IR camera 12 to the analysis device 24 . The analysis device 24 is an information processing device such as a personal computer. The analysis device 24 analyzes the first captured image and the second captured image received from the PLC 23 to determine the quality of the solar cell 20 .

FIG. 2 is a diagram showing the hardware configuration of the analysis device.
As shown in this figure, the analysis device 24 includes hardware such as a CPU 101 (CPU: Central Processing Unit), a ROM 102 (ROM: Read Only Memory), a RAM 103 (RAM: Random Access Memory), a capacity storage device 104, and a communication module 105. is a computer with

A program is stored in the ROM 102 . The CPU 101 reads a program from the ROM 102, develops it in the RAM 103, and executes processing according to the program. Also, the CPU 101 secures a predetermined storage area in the RAM 103 according to a program.

The program may be for realizing part of the functions that the analysis device 24 is caused to exhibit. For example, the program may function in combination with another program already stored in the storage or in combination with another program installed in another device. In other embodiments, the analysis device 24 may include a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device) in addition to or instead of the configuration shown in FIG. . Examples of PLD include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Array). In this case, part or all of the functions implemented by the CPU 101 may be implemented by the integrated circuit. Such an integrated circuit is also included as an example of a processor.

Also, the program may be for realizing part of the functions described above. Furthermore, the program may be a so-called difference file (difference program) that implements the above-described functions in combination with another program already stored in the ROM 102 .

FIG. 3 is a functional block diagram of the analysis device.
The analysis device 24 is activated when the power is turned on, and the CPU 101 executes the analysis program stored in the ROM 102 . Thus, the analysis device 24 includes at least a first image acquisition section 241 , a first analysis section 242 , a second image acquisition section 243 , a second analysis section 244 , a storage section 245 and an output section 246 .
The first image acquisition unit 241 receives and acquires the first captured image captured by the CCD camera 11 from the PLC 23 . The first image acquisition section 241 outputs the acquired first captured image to the first analysis section 242 .

The first analysis unit 242 analyzes the first captured image. That is, the first analysis unit 242 executes EL test analysis processing based on the first captured image. For example, the first analysis unit 242 determines the conductivity of the solar cell 20 based on the first captured image. Specifically, the first analysis unit 242 compares the first captured images before and after the energization, and identifies the light emitting portion that emits light based on the color difference. Then, the first analysis unit 242 determines that the electrical conductivity of the solar cell 20 is normal when the light-emitting portion is equal to or greater than a predetermined proportion of the whole, and determines that the solar cell 20 has normal conductivity when the light-emitting portion is less than the predetermined proportion of the whole. It is determined that the conductivity is abnormal. The first analysis unit 242 also determines the presence or absence of cracks in the solar cell 20 by performing image processing such as edge detection on the first captured image. The first analysis unit 242 writes the first captured image and the determination result based on the first captured image (hereinafter referred to as “EL test result”) in association with each other in the storage unit 245 . Also, the first analysis unit 242 outputs the first captured image and the EL test result based on the first captured image to the output unit 246 .

The second image acquisition unit 243 receives and acquires the second captured image captured by the IR camera 12 from the PLC 23 . The second image acquisition section 243 outputs the acquired second captured image to the second analysis section 244 .

A second analysis unit 244 analyzes the second captured image. That is, the second analysis unit 244 executes analysis processing for IR inspection based on the second captured image. For example, the second analysis unit 244 determines whether the bypass diode functions normally based on the second captured image. The second analysis unit 244 identifies the temperature of that portion from the brightness and hue of the solar cell 20 in the second captured image. Then, when the temperature exceeds a predetermined threshold, the second analysis unit 244 determines that there is an abnormality in or near that portion. Also, the second analysis unit 244 determines that the bypass diodes are functioning normally when the temperature of the solar cell 20 as a whole is equal to or lower than the threshold. The second analysis unit 244 associates the second captured image with the determination result based on the second captured image (hereinafter referred to as “IR inspection result”) and writes them in the storage unit 245 . The second analysis unit 244 also outputs the second captured image and the IR inspection result based on the second captured image to the output unit 246 .

The storage unit 245 associates and stores the first captured image and the EL test result based on the first captured image. The storage unit 245 also stores the second captured image and the IR inspection result based on the second captured image in association with each other.
The output unit 246 displays the first captured image and the EL test result based on the first captured image on a display or the like. The output unit 246 also displays the second captured image and the IR inspection result based on the second captured image on a display or the like. Alternatively, the output unit 246 may transmit the first captured image and the EL inspection result based on the first captured image, or the second captured image and the IR inspection result based on the second captured image to another device.

FIG. 4 is a diagram showing the processing flow of the inspection device.
Next, an inspection method by the inspection apparatus 1 will be described. The operation of the inspection apparatus 1 in each process from the first process to the seventh process in the inspection will be described below.

FIG. 5 is a diagram showing the state of the inspection apparatus in the first step of inspection.
First, in the first step, an inspector installs the assembly (the solar cell 20 to which the bypass diode and the connector 21 are connected) at a specified position on the metal plate 14 .

FIG. 6 is a diagram showing the state of the inspection apparatus in the second step of inspection.
Subsequently, in the second step, the operator pushes the switch 25 on the axis controller 22 . The inspection apparatus 1 is activated when the switch 25 receives an input.

FIG. 7 is a diagram showing the state of the inspection apparatus in the third step of inspection.
In the third step, the axis controller 22 moves the metal plate 14 on the Y-axis 13 along the Y-axis, and moves the measuring unit 18 along the X-axis 15 to move the metal plate 14, which is the stage. Alignment is performed (step S101). The axis controller 22 moves the metal plate 14 and the measurement unit 18 so that the probe 17 is directly above the connector 21 .

FIG. 8 is a diagram showing the state of the inspection apparatus in the fourth step of inspection.
In the fourth step, the axis controller 22 lowers the measurement unit 18 along the Z-axis 16 (moves in the downward direction AR18) to bring the probe 17 into contact with the connector 21 (step S102).

FIG. 9 is a diagram showing the state of the inspection apparatus in the fifth step of inspection.
In the fifth step, the PLC 23 turns on the first power supply section 19-1 to operate (step S103). As a result, a forward current is applied to the solar cell 20, and the solar cell 20 is energized. The solar cell 20 emits light when energized. Subsequently, the PLC 23 controls the CCD camera 11 to image the solar cell 20 (step S104). The PLC 23 transmits the first captured image captured by the CCD camera 11 to the analysis device 24 .

The analysis device 24 executes EL test analysis processing based on the first captured image (step S105). When the first captured image is captured, current is flowing in the forward direction to the solar cell 20. Therefore, if the electrical conductivity of the solar cell 20 is normal, electrons enter the holes of the solar cell 20, Battery 20 emits light. Therefore, the first analysis unit 242 of the analysis device 24 identifies the portion emitting light from the first captured image, and if the portion emitting light is a predetermined proportion or more of the whole, the electrical conductivity of the solar cell 20 is reduced. Judge as normal. Further, the first analysis unit 242 determines that the electrical conductivity of the solar cell 20 is abnormal when the light-emitting portion is less than a predetermined percentage of the whole. Moreover, when the solar cell 20 has a crack, the portion of the crack appears as a black line in the first captured image. Therefore, the first analysis unit 242 also determines whether there is a crack in the solar cell 20 by performing edge detection or the like on the first captured image. The output unit 246 displays the first captured image and the EL test result on a display or the like.

FIG. 10 is a diagram showing the state of the inspection apparatus in the sixth step of inspection.
In the sixth step, the PLC 23 turns off the first power supply section 19-1 to stop the operation (step S106). Then, the PLC 23 turns on the second power supply section 19-2 to operate (step S107). As a result, a current is applied in the opposite direction to the solar cell 20 and the bypass diode is energized. Subsequently, PLC 23 controls IR camera 12 to image solar cell 20 (step S108). PLC 23 transmits the second captured image captured by IR camera 12 to analysis device 24 .

The analysis device 24 executes analysis processing for the IR inspection based on the second captured image (step S109). When the second captured image is captured, current flows in the reverse direction to the solar cell 20, but if the bypass diode is functioning normally, the bypass diode bypasses the reverse current to the solar cell 20. Therefore, heat generation of the solar cell 20 can be suppressed. On the other hand, when the bypass diode has a failure or is not properly connected to the solar cell 20, a load is applied to the bypass diode or the solar cell 20 in the vicinity thereof, and heat is generated. Therefore, the second analysis unit 244 of the analysis device 24 identifies the temperature of the solar cell 20 from the second captured image, and determines that there is an abnormality in or near that portion when the temperature exceeds a predetermined threshold. Further, the second analysis unit 244 determines that the bypass diodes are functioning normally when the temperature of the solar cell 20 as a whole is equal to or lower than the threshold. The output unit 246 displays the second captured image and the IR inspection result on a display or the like. After that, the PLC 23 turns off the second power supply section 19-2 to stop the operation (step S110).

FIG. 11 is a diagram showing the state of the inspection apparatus in the seventh step of inspection.
In the seventh step, when the inspection is completed, the axis controller 22 moves the metal plate 14 and the measuring unit 18 to designated positions (eg, initial positions) (step S111). After that, the inspection apparatus 1 ends the processing. This completes the inspection of the solar cell 20 to which the bypass diode and the connector 21 as an assembly are connected. The worker retrieves the assembly from the inspection device 1 after the inspection is completed. The inspection method shown in the process described above allows efficient inspection of the assembly.

Thus, according to the present embodiment, the inspection apparatus 1 supplies the solar cell 20 to which the bypass diode and the connector 21 are connected, in the same forward direction as the current generated by the solar cell 20 through the connector 21 . A first power supply unit 19-1 that supplies current, a CCD camera 11 that captures a first captured image showing the light emission state of the solar cell 20 when current is supplied in the forward direction, and a first captured image that analyzes the first captured image. The temperature of the analysis part 242, the second power supply part 19-2 that causes the current to flow through the solar cell 20 through the connector 21 in the reverse direction to the forward direction, and the temperature of the solar cell 20 when the current flows in the reverse direction. It includes an IR camera 12 that captures a second captured image, and a second analysis section 244 that analyzes the second captured image. Thereby, both EL inspection and IR inspection can be performed with one inspection apparatus 1 . Therefore, space saving and cost reduction of equipment can be realized.

The inspection apparatus 1 also includes a metal plate 14 on which the solar cell 20 is installed, and the first power supply unit 19-1 and the second power supply unit 19-2 are electrically connected to the solar cell 20 through the metal plate 14. do. As a result, the EL inspection and the IR inspection can be performed simultaneously at one location on the metal plate 14, which is the stage. Therefore, since the EL inspection and the IR inspection can be performed without moving the solar cell 20 to be inspected, the inspection of the solar cell 20 can be efficiently performed.

The inspection apparatus 1 also includes a probe 17 that automatically contacts the connector 21 of the solar cell 20 installed on the metal plate 14. The first power supply unit 19-1 and the second power supply unit 19-2 are connected is electrically connected to the solar cell 20 via the . As a result, the operator simply installs the solar cell 20 at the specified position on the metal plate 14, and the inspection apparatus 1 automatically performs both the EL inspection and the IR inspection, so that the lead time of the inspection process can be shortened. . In addition, the process yield can be improved by reducing the handling work.

Further, the first analysis unit 242 determines that the electrical conductivity of the solar cell 20 is normal when the light-emitting portion of the solar cell 20 is equal to or more than a predetermined proportion of the whole in the first captured image, and the light-emitting portion is the entirety. On the other hand, when it is less than the predetermined ratio, it is determined that the conductivity of the solar cell 20 is abnormal. This makes it possible to inspect the electrical conductivity of the solar cell 20, that is, the quality of the connection between the solar cell 20 and the connector 21. FIG.

In addition, the second analysis unit 244 determines that the bypass diodes are functioning normally when the temperature of the solar cell 20 as a whole is equal to or lower than the predetermined threshold value in the second captured image. Thereby, it is possible to inspect whether the bypass diode is functioning normally, that is, whether the connection between the solar cell 20 and the bypass diode is good or bad.

Also, the first analysis unit 242 determines whether or not there is a crack in the solar cell 20 based on the first captured image. Thereby, the presence or absence of cracks in the solar cell 20 can be inspected.

FIG. 12 is a diagram showing the minimum configuration of the inspection device.
The inspection apparatus 1 may have at least the functions of the first power supply section 19-1, the CCD camera 11, the first analysis section 242, the second power supply section 19-2, the IR camera 12, and the second analysis section 244. .
The first power supply section 19-1 supplies current to the solar cell 20 to which the bypass diode is connected in the forward direction opposite to the current generated by the solar cell 20. FIG.
The CCD camera 11 captures a first captured image showing the light emitting state of the solar cell 20 when current is passed in the forward direction.
The first analysis unit 242 analyzes the first captured image.
The second power supply section 19-2 supplies current to the solar cell 20 in the opposite direction, which is the same direction as the current generated by the solar cell 20. FIG.
The IR camera 12 captures a second captured image showing the temperature of the solar cell 20 when the current is passed in the reverse direction.
The second analysis unit 244 analyzes the second captured image.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

For example, in the above-described embodiment, the inspection apparatus 1 performs the IR inspection after the EL inspection, but the present invention is not limited to this, and the EL inspection may be performed after the IR inspection.

In addition, each embodiment of the present invention is not limited to the combination of EL inspection and IR inspection, and can be applied to other inspection apparatuses and inspection methods as long as the inspection uses two types of cameras at the same time to analyze captured images. is.

The analysis device 24 and PLC 23 described above have a computer system inside. Each process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by reading and executing this program by a computer. Here, the computer-readable recording medium refers to magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, semiconductor memories, and the like. Alternatively, the computer program may be distributed to a computer via a communication line, and the computer receiving the distribution may execute the program.

Further, the program may be for realizing part of the functions described above. Further, it may be a so-called difference file (difference program) that can realize the above-described functions in combination with a program already recorded in the computer system.

1 inspection device 11 CCD camera 12 IR camera 13 Y axis 14 metal plate 15 X axis 16 Z axis 17 probe 18 measurement unit 19 power supply 19-1 first power supply section 19-2 second power supply section 20 solar cell 21 connector 22 axis control Controller 23 PLC
24 analysis device 241 first image acquisition unit 242 first analysis unit 243 second image acquisition unit 244 second analysis unit 245 storage unit 246 output unit 25 switch

Claims (7)

a probe for contacting the connector of the solar cell to which the bypass diode is connected;
a first power supply unit that supplies current to the solar cell through the probe in a forward direction, which is a direction opposite to the current generated by the solar cell;
a first imaging unit that captures a first captured image showing a light emitting state of the solar cell when the current is passed in the forward direction;
a first analysis unit that analyzes the first captured image;
a second power supply unit that applies a current to the solar cell via the probe in a direction opposite to the current generated by the solar cell;
a second imaging unit that captures a second captured image showing the temperature of the solar cell when the current is passed in the opposite direction;
a second analysis unit that analyzes the second captured image;
with
Switching between the first power supply unit and the second power supply unit to supply current while the probe and the connector are in contact with each other
inspection equipment. A metal plate for installing the solar cell,
The inspection device according to claim 1, wherein the first power supply section and the second power supply section are electrically connected to the solar cell through the metal plate. The probe automatically contacts the connector of the solar cell installed on the metal plate.
The inspection device according to claim 2. The first analysis unit determines that the electrical conductivity of the solar cell is normal when the light emitting portion of the solar cell is a predetermined proportion or more of the whole in the first captured image, and determines that the light emitting portion is a predetermined proportion of the whole. The inspection apparatus according to any one of claims 1 to 3, wherein it is determined that the electrical conductivity of the solar cell is abnormal when the ratio is less than the ratio. 5. Any one of claims 1 to 4, wherein the second analysis unit determines that the bypass diode is functioning normally when the temperature of the entire solar cell is equal to or less than a predetermined threshold value in the second captured image. or the inspection device according to item 1. The inspection apparatus according to any one of claims 1 to 5, wherein the first analysis unit determines whether or not there is a crack in the solar cell based on the first captured image. a probe for contacting the connector of the solar cell to which the bypass diode is connected;
Passing a current through the probe in a forward direction opposite to the current generated by the solar cell to the solar cell,
Capturing a first captured image showing a light emitting state of the solar cell when the current is passed in the forward direction;
analyzing the first captured image;
passing a current through the probe through the solar cell in the opposite direction, which is the same direction as the current generated by the solar cell;
Capturing a second captured image showing the temperature of the solar cell when the current is passed in the opposite direction;
analyzing the second captured image ;
Switching the direction of current flow while the probe and the connector are in contact with each other
Inspection method.

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