A fiber optic sensor system

Abstract

The present application provides a fiber optic sensor system. The system includes a power conversion module, which is used to step down the power supply voltage to generate a first voltage, a second voltage, a third voltage and a fourth voltage; an optical transmission module, which is powered by a first voltage, is used to output a first optical signal according to a pulse signal, and adjust the first optical signal according to a control voltage, and adjust the first optical signal according to an ambient temperature; an automatic power control module, which is powered by a second voltage, is used to generate a power control signal according to the first optical signal; an optical receiving module, which is powered by a second voltage, is used to convert the second optical signal into a detection electrical signal; a display module, which is powered by a third voltage, is used to receive display instructions. A main control module, which is powered by a fourth voltage, is used to output a pulse signal and a display instruction, and output a control voltage according to a power control signal, and output a detection result signal according to a detection electrical signal. The present application realizes real-time compensation of the first optical signal and improves the reliability of the fiber optic sensor.

Description

Technical Field

[0001] The present application relates to the field of optoelectronic technology, and in particular to an optical fiber sensor system. Background Art

[0002] With the continuous improvement of industrial automation, fiber optic sensors, as precision detection and measurement tools, have been widely used in many industries due to their advantages such as high precision, fast response and non-contact measurement. However, although fiber optic sensor technology has made significant progress, there are still some technical limitations in practical applications, which restricts its further performance improvement and wider application.

[0003] However, traditional fiber optic sensors can usually only maintain stable transmission of optical signals under a single environmental condition. But when the environmental conditions change or they are used for a long time, the intensity of the optical signal they emit can be easily damaged. This makes it difficult for traditional fiber optic sensors to maintain long-term stable operation, thus affecting their reliability and service life. Summary of the invention

[0004] In view of the above problems, the present application provides a fiber optic sensor system to solve the above technical problems.

[0005] The optical fiber sensor system provided in this application includes:

[0006] A power conversion module, used for connecting to a power source and stepping down a power source voltage to generate a first voltage, a second voltage, a third voltage and a fourth voltage;

[0007] The optical transmission module is powered by a first voltage, and is used to output a first optical signal according to the pulse signal, and to adjust the first optical signal according to an adjustable control voltage, and to adjust the first optical signal according to an ambient temperature, wherein the first optical signal is transmitted from the transmitting optical fiber to a target area, and after passing through the target area, a second optical signal is formed and transmitted to a receiving optical fiber;

[0008] an automatic power control module, powered by a second voltage, for generating a power control signal according to the first optical signal, so as to adjust the control voltage through the power control signal;

[0009] The optical receiving module is powered by a second voltage and is used to receive a second optical signal and convert the second optical signal into a detection electrical signal for output; the second optical signal is transmitted from the receiving optical fiber to the optical receiving module;

[0010] The display module is powered by a third voltage and is used to receive a display instruction to display preset parameters.

[0011] The main control module is powered by a fourth voltage and is used to output pulse signals and display instructions, output control voltage according to the power control signal, and output a detection result signal according to the detection electrical signal. The detection result signal is used to indicate whether a target detection object exists in the target area.

[0012] The optical fiber sensor system provided by the present application, the embodiment of the present application converts the power supply voltage into the power supply voltage required by each module through the power conversion module to power each module, the automatic power control module outputs a power control signal to adjust the control voltage by detecting the intensity of the first optical signal, the optical transmission module receives the adjustable control voltage to adjust the luminous intensity of the first optical signal generated by the optical transmission module, and also adjusts the luminous intensity of the first optical signal according to the ambient temperature, thereby realizing real-time compensation of the optical signal emitted by the optical transmission module, so that the optical fiber sensor can work in different environmental conditions.

[0013] In addition, the fiber optic sensor system provided by the present application enables the display module and the main control module to be powered by different power supply systems. In this way, even if the power consumption of the display module is large, it will not affect the power supply system of the main control module, thereby making the power ripple of the main control module more stable. Compared with the traditional fiber optic sensor that uses the same power supply system for the display module and the main control module, the power ripple of the main control module is increased due to the large power consumption of the display module, resulting in power instability. The embodiment of the present application significantly reduces the power ripple of the main control module, improves the stability of the main control module, and thereby improves the detection accuracy and detection range of the fiber optic sensor.

[0014] These and other aspects of the present application will become more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A module schematic diagram of the optical fiber sensor system provided in an embodiment of the present application is shown.

[0017] Figure 2 A module schematic diagram of a power conversion module provided in an embodiment of the present application is shown.

[0018] Figure 3 A module schematic diagram of the optical transmission module provided in an embodiment of the present application is shown.

[0019] Figure 4A schematic diagram of the structure of the optical transmission module provided in an embodiment of the present application is shown.

[0020] Figure 5 A module schematic diagram of an automatic power control module provided in an embodiment of the present application is shown.

[0021] Figure 6 A schematic diagram of the structure of an automatic power control module provided in an embodiment of the present application is shown.

[0022] Figure 7 A module schematic diagram of an optical receiving module provided in an embodiment of the present application is shown.

[0023] Figure 8 Another module schematic diagram of the optical fiber sensor system provided in an embodiment of the present application is shown.

[0024] Fig. 9 Another module schematic diagram of the optical fiber sensor system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0026] In the embodiments of the present application, it should be noted that, in this article, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0027] Moreover, the terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0028] It should be noted that in the embodiments of the present application, "connection" can be understood as electrical connection, and the connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be either a direct connection between A and B or an indirect connection between A and B through one or more other electrical components.

[0029] The first end of each transistor used in the embodiment of the present application is one of the collector and the emitter, and the second end of each transistor is the other of the collector and the emitter. Since the collector and the emitter of the transistor can be symmetrical in structure, the collector and the emitter can be indistinguishable in structure, that is, the first end and the second end of the transistor in the embodiment of the present application can be indistinguishable in structure.

[0030] The present application embodiment provides a fiber optic sensor system, Figure 1 The module schematic diagram of the optical fiber sensor system provided in the embodiment of the present application is shown as follows: Figure 1 As shown, the optical fiber sensor system includes a power conversion module, an optical transmission module, an automatic power control module, an optical receiving module, a display module and a main control module.

[0031] The power conversion module is used to connect the power supply and step down the power supply voltage to generate the first voltage, the second voltage, the third voltage and the fourth voltage. The optical transmission module is powered by the first voltage, and is used to output the first optical signal according to the pulse signal, and adjust the first optical signal according to the adjustable control voltage, and adjust the first optical signal according to the ambient temperature. The first optical signal is transmitted from the transmitting optical fiber to the target area, and after passing through the target area, a second optical signal is formed and transmitted to the receiving optical fiber. The automatic power control module is powered by the second voltage, and is used to generate a power control signal according to the first optical signal, so as to adjust the control voltage through the power control signal. The optical receiving module is powered by the second voltage, and is used to receive the second optical signal, convert the second optical signal into a detection electrical signal and output it; the second optical signal is transmitted from the receiving optical fiber to the optical receiving module. The display module is powered by the third voltage, and is used to receive a display instruction to display a preset parameter. The main control module is powered by the fourth voltage, and is used to output a pulse signal and a display instruction, and output a control voltage according to the power control signal, and output a detection result signal according to the detection electrical signal, and the detection result signal is used to indicate whether there is a target detection object in the target area.

[0032] Optionally, the embodiment of the present application converts the power supply voltage into the power supply voltage required by each module through the power conversion module to power each module. The automatic power control module outputs a power control signal to adjust the control voltage by detecting the intensity of the first optical signal. For example, when the intensity of the first optical signal decreases, the automatic power control module will increase the control voltage. The optical transmission module receives the adjustable control voltage to adjust the luminous intensity of the first optical signal generated by the optical transmission module, and also adjusts the luminous intensity of the first optical signal according to the ambient temperature, thereby realizing real-time compensation of the optical signal emitted by the optical transmission module, so that the optical fiber sensor can operate under different environmental conditions.

[0033] In addition, in the embodiment of the present application, the display module and the main control module are powered by different power supply systems. In this way, even if the power consumption of the display module is large, it will not affect the power supply system of the main control module, thereby making the power ripple of the main control module more stable. Compared with the traditional optical fiber sensor, the display module and the main control module use the same power supply system. Because the power consumption of the display module is large, the power ripple of the main control module is increased, resulting in power instability. The embodiment of the present application significantly reduces the power ripple of the main control module, improves the stability of the main control module, and thereby improves the detection accuracy and detection range of the optical fiber sensor.

[0034] In some embodiments, the display module is a display screen device.

[0035] In some embodiments, the display module is an LED display screen.

[0036] It can be understood that in the embodiment of the present application, the main control module is a chip with central processing unit capabilities. When the main control module transmits different signals with other modules, it is connected to each module through different IO ports. For example, the main control module can be an MCU (microcontroller), a single-chip microcomputer, etc.

[0037] It can be understood that the fiber optic sensor system provided in the embodiment of the present application is applied to a fiber optic sensor, wherein the transmitting fiber and the receiving fiber are components of the fiber optic sensor itself, and therefore the embodiment of the present application does not further explain the transmitting fiber and the receiving fiber.

[0038] The optical fiber sensor system provided by the embodiment of the present application realizes real-time compensation of the optical signal emitted by the optical transmission module, so that the optical fiber sensor can work in different environmental conditions and can be applied to environmental conditions with constantly changing temperatures. In addition, the embodiment of the present application greatly reduces the power ripple of the main control module and improves the stability of the main control module's transceiver signal. Due to the stability of the transceiver signal and the reduction of the power ripple, the embodiment of the present application can significantly improve the detection accuracy and detection range of the optical fiber sensor.

[0039] In some embodiments, Figure 2A schematic diagram of a power conversion module provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, in the embodiment of the present application, the power conversion module includes:

[0040] The first power conversion unit is used to connect to a power source and convert a power source voltage into a first voltage. The second power conversion unit is connected to the first power conversion unit and converts the first voltage into a second voltage. The third power conversion unit is used to connect to a power source and convert the power source voltage into a third voltage. The fourth power conversion unit is connected to the second power conversion unit and converts the second voltage into a fourth voltage.

[0041] In the embodiment of the present application, the display module and the main control module are powered by the third power conversion unit and the fourth power conversion unit respectively, and the third power conversion unit directly converts the power supply voltage, so that the display module with high power consumption uses a separate power supply system. Compared with the traditional optical fiber sensor that makes the display module and the main control module use the same power supply system, the embodiment of the present application greatly reduces the power ripple of the fourth power conversion unit and improves the stability of the receiving and transmitting signals of the main control module. Due to the stability of the receiving and transmitting signals and the reduction of the power ripple, the embodiment of the present application can significantly improve the detection accuracy and detection range of the optical fiber sensor.

[0042] In some embodiments, in the embodiment of the present application, the first voltage is 7V, which is used to power the optical transmission module, the second voltage is 5V, which is used to power the automatic power control module and the optical receiving module, the third voltage is 3.3V, which is used to power the display module, and the fourth voltage is 3.3V, which is used to power the main control module.

[0043] In some embodiments, the first power conversion unit and the third power conversion unit are used to convert the power supply voltage of the large current into a small voltage (the first voltage and the third voltage). The embodiment of the present application uses a direct current-to-direct current converter chip (DC-DC) for voltage conversion to improve conversion efficiency. The second power conversion unit and the fourth power conversion unit are used to convert the small voltage (the first voltage) of the small current into a smaller voltage (the second voltage and the fourth voltage). The embodiment of the present application uses a low dropout linear regulator chip (LDO, Low Dropout Regulator) for voltage conversion to improve power conversion accuracy.

[0044] It is understandable that designing a power conversion unit to convert voltage is a routine method for those skilled in the art, and therefore the embodiments of the present application do not limit the specific circuit structure of each power conversion unit.

[0045] In some embodiments, Figure 3 A schematic diagram of a light transmitting module provided in an embodiment of the present application is shown. Figure 3As shown, in the embodiment of the present application, the optical transmission module includes a first switch unit, a second switch unit, a temperature compensation unit and a light emitting unit.

[0046] The first switch unit is connected to the light emitting unit and is used to receive a pulse signal to control the light emitting unit to emit a first light signal when it is turned on. The second switch unit is connected to the first switch unit and is used to receive a control voltage to adjust the first light signal according to the control voltage when it is turned on. The temperature compensation unit is connected to the first switch unit and is used to enhance the first light signal as the temperature rises and reduce the first light signal as the temperature drops. The light emitting unit is connected to the power conversion module to be powered by a first voltage.

[0047] Optionally, in an embodiment of the present application, when the pulse signal output by the main control module is pulled low, the first switch unit is not turned on, so that the light-emitting unit does not emit light; when the pulse signal is pulled high, the first switch unit is turned on, so that the light-emitting unit emits light. After the first switch unit is turned on, the second switch unit increases or decreases the current in the light-emitting unit circuit by receiving an adjustable control voltage, thereby adjusting the intensity of the first light signal emitted by the light-emitting unit. After the first switch unit is turned on, when the ambient temperature rises, the temperature compensation unit will increase the current in the light-emitting unit circuit, thereby enhancing the intensity of the first light signal emitted by the light-emitting unit. When the ambient temperature decreases, the temperature compensation unit will make the current in the light-emitting unit circuit effective, thereby reducing the intensity of the first light signal emitted by the light-emitting unit.

[0048] In some embodiments, Figure 4 The structure diagram of the optical transmission module provided in the embodiment of the present application is shown as follows: Figure 4 As shown, the first switch unit includes a first transistor Q1, a first resistor R1 and a second resistor R2.

[0049] The control end of the first transistor receives a pulse signal through the first resistor and receives a control voltage through the second switch unit, the first end is connected to the light-emitting unit, the second end is grounded through the second switch unit and the temperature compensation unit respectively, the first end of the first resistor is connected to the first transistor, the second end is connected to the first end of the second resistor, and is connected to the main control module to receive the pulse signal, and the second end of the second resistor is grounded. Optionally, the first resistor is a current limiting resistor of the first transistor, and the second resistor is a grounding resistor, which is used to keep the control end of the first transistor at a low level before the light-emitting module is powered on.

[0050] In some embodiments, the first transistor is an NPN transistor.

[0051] It can be understood that in the embodiment of the present application, the first resistor and the second resistor are not necessary electronic components that constitute the first switching unit. In fact, the embodiment of the present application can also use electronic components / circuits with the same functions as the first resistor and the second resistor to replace the first resistor and the second resistor.

[0052] The second switch unit includes a second transistor Q2, a first diode D0, a third resistor R3, a fourth resistor R4 and a first capacitor C1.

[0053] The control end of the second transistor is connected to the anode of the first diode, and the first end is connected to the first switch unit; the second end is respectively connected to the first end of the third resistor and the first end of the first capacitor, the second end of the third resistor is connected to the main control module to receive the control voltage, the second end of the first capacitor is grounded, the anode of the first diode is also connected to the first switch unit, the cathode is connected to the first end of the fourth resistor, and the first end of the fourth resistor is grounded. Optionally, the first diode is used as a switching diode, so that the voltage drop of the control end of the second transistor is approximately 0.7V, so that the base of the second transistor maintains a certain voltage, the fourth resistor is a current limiting resistor, the third resistor, the first capacitor and the second transistor form a constant current circuit, so as to adjust the current output by the first transistor by receiving the control voltage, wherein the third resistor and the first capacitor are also used to form a filtering current limiting circuit.

[0054] In some embodiments, the second transistor is an NPN transistor.

[0055] It can be understood that in the embodiment of the present application, the first diode, the third resistor, the fourth resistor and the first capacitor are not necessary electronic components that constitute the second switching unit. In fact, the embodiment of the present application can also use electronic components / circuits with the same functions to replace the first diode, the third resistor, the fourth resistor and the first capacitor.

[0056] The temperature compensation unit includes a temperature-sensitive resistor RV, a fifth resistor R5 and a sixth resistor R6.

[0057] The first end of the temperature-sensitive resistor is connected to the first switch unit through the fifth resistor and to the first end of the sixth resistor. The second end of the temperature-sensitive resistor is connected to the second end of the sixth resistor and is grounded.

[0058] Optionally, because of the temperature drift effect of the transistor, when the ambient temperature is high, the conduction degree of the first transistor will be weakened, so that the intensity of the first light signal emitted by the light-emitting unit will be reduced, and the resistance of the thermistor will be reduced in the high temperature environment, thereby increasing the current of the temperature compensation unit. At this time, the current passing through the first transistor increases, thereby increasing the intensity of the first light signal emitted by the light-emitting unit. The working principle of the temperature compensation unit in a low temperature environment is opposite to that in a high temperature environment.

[0059] The light emitting unit includes a first light emitting diode D1, a seventh resistor R7 and a second capacitor C2.

[0060] The anode of the first light emitting diode is connected to the first end of the seventh resistor and the first end of the second capacitor respectively, the cathode is connected to the first switch unit, the second end of the seventh resistor is connected to the power conversion module to receive the first voltage, and the second end of the second capacitor is grounded. Optionally, the seventh resistor and the second capacitor are used to form a current limiting filter circuit.

[0061] It can be understood that in the embodiment of the present application, the seventh resistor and the second capacitor are not necessary electronic components that constitute the light-emitting unit. In fact, the embodiment of the present application can also use electronic components / circuits with the same functions to replace the seventh resistor and the second capacitor.

[0062] The optical fiber sensor system provided in the embodiment of the present application receives a control voltage through a second switch unit to adjust the current size of the light-emitting unit circuit, so as to adjust the intensity of the first light signal emitted by the light-emitting unit, and controls the current size of the light-emitting unit circuit under different temperature environments through a temperature compensation unit to adjust the intensity of the first light signal emitted by the light-emitting unit, so that the optical fiber sensor can operate in different environmental conditions and can be suitable for environmental conditions with constantly changing temperatures, thereby improving the reliability and applicability of the optical fiber sensor.

[0063] In some embodiments, Figure 5 FIG. 4 shows a schematic diagram of an automatic power control module provided in an embodiment of the present application. Figure 5 As shown, the automatic power control module includes:

[0064] The first photoelectric conversion unit is used to receive a first optical signal to generate a first electrical signal.

[0065] The first voltage amplifying unit is used to receive a first electrical signal, amplify the first electrical signal and output a second electrical signal.

[0066] The first voltage follower unit is used to convert the second electrical signal into a power control signal.

[0067] In some embodiments, Figure 6 FIG. 4 shows a schematic diagram of the structure of the automatic power control module provided in an embodiment of the present application. Figure 6 As shown, the first photoelectric conversion unit includes a first photodiode PD1 and an eighth resistor R8.

[0068] The anode of the first photodiode is grounded, the cathode is connected to the first voltage amplification unit, and is connected to the power conversion module through the eighth resistor to receive the second voltage. Optionally, the first photodiode is used to convert the first optical signal into a first electrical signal, and the eighth resistor R8 is a pull-up load resistor.

[0069] It can be understood that in the embodiment of the present application, the eighth resistor is not a necessary electronic device for constituting the first photoelectric conversion unit. In fact, the embodiment of the present application can also use an electronic device / circuit with the same function to replace the eighth resistor.

[0070] The first voltage amplifying unit includes a first operational amplifier A1, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a third capacitor C3, a fourth capacitor C4 and a fifth capacitor C5.

[0071] The positive input terminal of the first operational amplifier is respectively connected to the first end of the ninth resistor, the first end of the tenth resistor and the first end of the third capacitor, the reverse input terminal is respectively connected to the first end of the fourth capacitor, the first end of the fifth capacitor and the first end of the eleventh resistor, the output terminal is respectively connected to the second end of the eleventh resistor, the second end of the fifth capacitor and the first voltage follower unit, the second end of the ninth resistor is connected to the power conversion module to receive the second voltage, the second end of the tenth resistor and the second end of the third capacitor are grounded, and the second end of the fourth capacitor is connected to the first photoelectric conversion unit.

[0072] Optionally, the ninth resistor and the tenth resistor are used to form a voltage divider circuit to provide a voltage reference for the positive input terminal of the first operational amplifier, the third capacitor is used for filtering, the fourth capacitor is used for AC isolation, the fifth capacitor and the eleventh resistor are used to form a low-pass filter circuit, and the values ​​of the fourth capacitor, the fifth capacitor and the eleventh resistor are used to control the voltage value of the second voltage signal output by the first operational amplifier.

[0073] In some embodiments, the voltage value of the second voltage signal does not exceed 3.3V, so that the main control module powered by 3.3V can receive the power control signal converted from the second voltage signal.

[0074] The first voltage follower unit includes a second operational amplifier A2, a twelfth resistor R12, and a sixth capacitor C6.

[0075] The positive input terminal of the second operational amplifier is connected to the first voltage amplification unit, the reverse input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier, the output terminal of the second operational amplifier is also grounded through the twelfth resistor and the sixth capacitor, and is connected to the main control module through the twelfth resistor to output a power control signal to the main control module. Optionally, the twelfth resistor and the sixth capacitor are used to form a current limiting filter circuit.

[0076] It can be understood that in the embodiment of the present application, the twelfth resistor and the sixth capacitor are not necessary electronic components for constituting the first voltage amplification unit. In fact, the embodiment of the present application can also use electronic components / circuits with the same functions to replace the twelfth resistor and the sixth capacitor.

[0077] In the optical fiber sensor system provided in the embodiment of the present application, when the intensity of the first optical signal emitted by the optical transmitting module is automatically adjusted, the initial luminous intensity of the first light-emitting diode is made lower than 100%. In this way, when the optical signal emitted by the first light-emitting diode has light decay, the power control signal output by the automatic power control module will be reduced synchronously, and then the main control module increases the control voltage after the power control signal is reduced, thereby enhancing the luminous intensity of the first light-emitting diode.

[0078] It can be understood that in the embodiment of the present application, there is no restriction on the specific structures of the first photoelectric conversion unit, the first voltage amplification unit, and the first voltage follower unit, and the circuit structure that can realize the corresponding function is not limited to the above one.

[0079] In some embodiments, Figure 7 A schematic diagram of a light receiving module provided in an embodiment of the present application is shown. Figure 7 As shown, the optical receiving module includes:

[0080] The second photoelectric conversion unit is used to receive the second optical signal to generate a third electrical signal.

[0081] The second voltage amplifying unit is used to receive the third electrical signal, amplify the third electrical signal and output a fourth electrical signal.

[0082] The third voltage amplifying unit is used to receive the fourth electrical signal, amplify the fourth electrical signal and output a fifth electrical signal.

[0083] The second voltage follower unit is used to convert the fifth electrical signal into a detection electrical signal.

[0084] Optionally, the optical receiving module is used to convert the second optical signal output by the receiving optical fiber into a third electrical signal, and generate a fifth electrical signal through diode amplification, and finally convert the fifth electrical signal into a detection electrical signal through a second voltage follower and output it to the main control module, so that the main control module can determine whether there is a detection object in the target area based on the detection electrical signal.

[0085] It can be understood that in the embodiments of the present application, the implementation of the second photoelectric conversion unit, the second voltage amplification unit, the third voltage amplification unit, and the second voltage follower unit is a conventional technical means for those skilled in the art. Therefore, the embodiments of the present application do not limit the specific structures of the second photoelectric conversion unit, the second voltage amplification unit, the third voltage amplification unit, and the second voltage follower unit. In fact, the circuit structure that can realize the corresponding function is not limited to one, and in the above embodiments, an implementation method of the photoelectric conversion unit, the voltage amplification unit, and the voltage follower unit has been given.

[0086] In some embodiments, each operational amplifier also includes a power supply terminal and a ground terminal. In this case, the power supply terminal of each operational amplifier needs to be connected to a corresponding power supply, the ground terminal needs to be grounded accordingly, and a corresponding current limiting circuit and filtering circuit need to be set according to actual needs.

[0087] In some embodiments, Figure 8 Another module schematic diagram of the optical fiber sensor system provided in the embodiment of the present application is shown in FIG. Figure 8 As shown, the optical fiber sensor system provided in the embodiment of the present application also includes a digital sensor driver based on the IO-LINK communication protocol, and the digital sensor driver is used to output an NPN signal or a PNP signal according to the output control signal generated by the main control module.

[0088] Traditional fiber optic sensors can only output NPN signals or PNP signals, resulting in insufficient application scenarios. In view of this, the fiber optic sensor system provided in the embodiment of the present application further expands the application scenarios of fiber optic sensors by setting a digital sensor driver based on the IO-LINK communication protocol to achieve an output mode compatible with NPN signals and PNP signals. Furthermore, the digital sensor driver based on the IO-LINK communication protocol can also be connected to the host computer through IO-LINK communication means, thereby realizing communication between the host computer and the main control module of the fiber optic sensor.

[0089] It can be understood that in the embodiment of the present application, the digital sensor driver is controlled to output an NPN signal or a PNP signal by controlling the main control module to output a corresponding output control signal, but the embodiment of the present application does not limit the control method of the main control module. For example, the main control module can set the high and low levels of the output control signal to make the digital sensor driver output an NPN signal or a PNP signal. For another example, the main control module can also output multiple level signals as output control signals, and the digital sensor driver is controlled by multiple level signals to output an NPN signal or a PNP signal.

[0090] In some embodiments, Fig. 9 Another module schematic diagram of the optical fiber sensor system provided in the embodiment of the present application is shown. Fig. 9 As shown, the optical fiber sensor system provided in the embodiment of the present application also includes a voltage level conversion unit, which is powered by a fourth voltage and is respectively connected to the main control module and the digital sensor driver, and is used to receive an output control signal generated by the main control module to convert the level of the output control signal from a first level to a second level, and output it to the digital sensor driver based on the IO-LINK communication protocol.

[0091] Optionally, in an embodiment of the present application, the power supply voltage of the main control module is 3.3V. When the power supply voltage of the digital sensor driver based on the IO-LINK communication protocol is not 3.3V, the embodiment of the present application realizes communication between the digital sensor driver and the main control module by setting a voltage level conversion unit.

[0092] In some embodiments, in the optical fiber sensor system provided by the embodiments of the present application, the main control module converts the power control signal into a first digital quantity, compares it with a preset first threshold value, and outputs the control voltage according to the comparison result, thereby outputting the control voltage according to the power control signal. The main control module converts the detection electrical signal into a second digital quantity, compares it with a preset second threshold value, and outputs a detection result signal according to the comparison result, thereby outputting a detection result signal according to the detection electrical signal. The main control module lowers the second threshold value when the second digital quantity is lower than a preset third threshold value, thereby adjusting the detection accuracy of the optical fiber sensor when the detection accuracy of the optical fiber sensor is reduced, thereby further improving the reliability of the optical fiber sensor.

[0093] In some embodiments, the optical fiber sensor system provided by the embodiments of the present application further includes:

[0094] The indication module is connected to the main control module and generates a corresponding indication according to a level signal output by the main control module. For example, if the level signal is high, the indication module indicates that there is a detection object in the target area; if the level signal is low, the indication module indicates that there is no detection object in the target area.

[0095] In some embodiments, the indication module is also used to indicate the power status according to a level signal output by the main control module. For example, when the main control module outputs a high level, the indication module indicates that the power supply is in a normal power-on state. When the level signal is a low level, the indication module indicates that the power supply is in an abnormal state.

[0096] It can be understood that the embodiments of the present application do not limit the specific structure of the above-mentioned indication module, as long as it can achieve the functions described in the above-mentioned embodiments. For example, the indication module can be set to indicate through light, and for example, the indication module can also be set to indicate through sound.

[0097] In some embodiments, the optical fiber sensor system provided by the embodiments of the present application further includes a control module, which is used to output different level signals to the main control module to set different states of the optical fiber sensor.

[0098] Exemplarily, the control module may include multiple function buttons for controlling the detection accuracy, detection frequency, preset first thresholds, second thresholds, third thresholds, intensity of the first light signal emitted by the optical transmission module, etc. of the optical fiber sensor.

[0099] It is understandable that, for those skilled in the art, setting the function buttons to configure the state of the optical fiber sensor is a conventional technical means, so the control module will not be described in detail in the embodiment of the present application.

[0100] The optical fiber sensor system provided in the embodiment of the present application is applied to optical fiber sensors, such as reflective optical fiber sensors and reflected optical fiber sensors. It can compensate the optical signal emitted by the optical transmission module in real time, and when the detection accuracy of the optical fiber sensor is reduced, it can automatically adjust the detection accuracy of the optical fiber sensor, thereby realizing the application of the optical fiber sensor in different environmental conditions, and can be suitable for environmental conditions with constantly changing temperatures, thereby improving the reliability of the optical fiber sensor.

[0101] In addition, the embodiments of the present application greatly reduce the power ripple of the main control module and improve the stability of the receiving and transmitting signals of the main control module. Due to the stability of the receiving and transmitting signals and the reduction of the power ripple, the embodiments of the present application can significantly improve the detection accuracy and detection range of the optical fiber sensor.

[0102] In addition, the embodiment of the present application is also provided with a digital sensor driver based on the IO-LINK communication protocol, which is compatible with outputting NPN signals and PNP signals, thereby expanding the output mode of the optical fiber sensor.

[0103] The above contents are further detailed descriptions of the present application in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be regarded as the protection scope of the present application.

Claims

1. A fiber optic sensor system, characterized in that: include: A power conversion module, used for connecting to a power source and stepping down a power source voltage to generate a first voltage, a second voltage, a third voltage and a fourth voltage; an optical transmission module, powered by the first voltage, configured to output a first optical signal according to a pulse signal, adjust the first optical signal according to an adjustable control voltage, and adjust the first optical signal according to an ambient temperature, wherein the first optical signal is transmitted from a transmitting optical fiber to a target area, and after passing through the target area, a second optical signal is formed and transmitted to a receiving optical fiber; an automatic power control module, powered by the second voltage, for generating a power control signal according to the first optical signal, so as to adjust the control voltage by the power control signal; an optical receiving module, powered by the second voltage, configured to receive the second optical signal, convert the second optical signal into a detection electrical signal for output; The second optical signal is transmitted from the receiving optical fiber to the optical receiving module; A display module, powered by the third voltage, for receiving a display instruction to display a preset parameter; a main control module, powered by the fourth voltage, used to output the pulse signal and the display instruction, and output the control voltage according to the power control signal, and output a detection result signal according to the detection electrical signal, wherein the detection result signal is used to indicate whether a target detection object exists in the target area; Wherein, the power conversion module comprises: A first power conversion unit, used for connecting to the power supply and converting the power supply voltage into a first voltage; a second power conversion unit, connected to the first power conversion unit, and configured to convert the first voltage into a second voltage; A third power conversion unit, used to connect to the power supply and convert the power supply voltage into a third voltage; a fourth power conversion unit, connected to the second power conversion unit, and configured to convert the second voltage into a fourth voltage, The optical transmission module comprises: a first switch unit, a second switch unit, a temperature compensation unit and a light emitting unit; The first switch unit is connected to the light emitting unit and is used to receive the pulse signal so as to control the light emitting unit to emit the first light signal when turned on; The second switch unit is connected to the first switch unit and is used to receive the control voltage so as to adjust the first optical signal according to the control voltage when being turned on; The temperature compensation unit is connected to the first switch unit, and is used to enhance the first optical signal as the temperature rises, and to reduce the first optical signal as the temperature drops; The light emitting unit is connected to the power conversion module to be powered by the first voltage.

2. The optical fiber sensor system according to claim 1, characterized in that: The first switch unit includes a first transistor, a first resistor and a second resistor; The control end of the first transistor receives the pulse signal through the first resistor and receives the control voltage through the second switch unit, the first end is connected to the light emitting unit, and the second end is grounded through the second switch unit and the temperature compensation unit respectively; The first end of the first resistor is connected to the first transistor, the second end is connected to the first end of the second resistor, and is connected to the main control module to receive the pulse signal, and the second end of the second resistor is grounded; The second switch unit includes a second transistor, a first diode, a third resistor, a fourth resistor and a first capacitor; The control end of the second transistor is connected to the anode of the first diode, the first end is connected to the first switch unit; the second end is respectively connected to the first end of the third resistor and the first end of the first capacitor; The second end of the third resistor is connected to the main control module to receive the control voltage, and the second end of the first capacitor is grounded; The anode of the first diode is also connected to the first switch unit, and the cathode is connected to the first end of the fourth resistor, and the first end of the fourth resistor is grounded; The temperature compensation unit includes a temperature-sensitive resistor, a fifth resistor and a sixth resistor; The first end of the temperature-sensitive resistor is connected to the first switch unit through the fifth resistor and is connected to the first end of the sixth resistor, and the second end of the temperature-sensitive resistor is connected to the second end of the sixth resistor and is grounded; The light emitting unit comprises a first light emitting diode, a seventh resistor and a second capacitor; The anode of the first light emitting diode is connected to the first end of the seventh resistor and the first end of the second capacitor respectively, and the cathode is connected to the first switch unit; The second end of the seventh resistor is connected to the power conversion module to receive the first voltage, and the second end of the second capacitor is grounded.

3. The optical fiber sensor system according to claim 1, characterized in that: The automatic power control module comprises: A first photoelectric conversion unit, configured to receive a first optical signal to generate a first electrical signal; A first voltage amplifying unit, configured to receive the first electrical signal, amplify the first electrical signal and output a second electrical signal; The first voltage follower unit is used to convert the second electrical signal into the power control signal.

4. The optical fiber sensor system according to claim 3, characterized in that: The first photoelectric conversion unit includes a first photodiode and an eighth resistor; The anode of the first photodiode is grounded, the cathode is connected to the first voltage amplification unit, and is connected to the power conversion module through the eighth resistor to receive the second voltage; The first voltage amplifying unit includes a first operational amplifier, a ninth resistor, a tenth resistor, an eleventh resistor, a third capacitor, a fourth capacitor and a fifth capacitor; The first operational amplifier has a positive input terminal connected to the first end of the ninth resistor, the first end of the tenth resistor and the first end of the third capacitor, a negative input terminal connected to the first end of the fourth capacitor, the first end of the fifth capacitor and the first end of the eleventh resistor, and an output terminal connected to the second end of the eleventh resistor, the second end of the fifth capacitor and the first voltage follower unit; The second end of the ninth resistor is connected to the power conversion module to receive the second voltage, the second end of the tenth resistor and the second end of the third capacitor are grounded, and the second end of the fourth capacitor is connected to the first photoelectric conversion unit; The first voltage follower unit includes a second operational amplifier, a twelfth resistor, and a sixth capacitor; The positive input terminal of the second operational amplifier is connected to the first voltage amplification unit, the reverse input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier, the output terminal of the second operational amplifier is also grounded through the twelfth resistor and the sixth capacitor, and is connected to the main control module through the twelfth resistor to output the power control signal to the main control module.

5. The optical fiber sensor system according to claim 1, characterized in that: The optical receiving module comprises: A second photoelectric conversion unit, configured to receive the second optical signal to generate a third electrical signal; a second voltage amplifying unit, configured to receive the third electrical signal, amplify the third electrical signal and output a fourth electrical signal; a third voltage amplifying unit, configured to receive the fourth electrical signal, amplify the fourth electrical signal and output a fifth electrical signal; The second voltage follower unit is used to convert the fifth electrical signal into the detection electrical signal.

6. The optical fiber sensor system according to claim 1, characterized in that: Also includes: A digital sensor driver based on the IO-LINK communication protocol, wherein the digital sensor driver is used to output an NPN signal or a PNP signal according to an output control signal generated by a main control module.

7. The optical fiber sensor system according to claim 6, characterized in that: Also includes: A voltage level conversion unit is powered by the fourth voltage and is respectively connected to the main control module and the digital sensor driver, and is used to receive an output control signal generated by the main control module to convert the level of the output control signal from a first level to a second level, and output it to the digital sensor driver based on the IO-LINK communication protocol.

8. The optical fiber sensor system according to claim 1, characterized in that: The main control module outputs the control voltage according to the power control signal, including: converting the power control signal into a first digital quantity, comparing it with a preset first threshold, and outputting the control voltage according to the comparison result, The main control module outputs a detection result signal according to the detection electrical signal, including: Converting the detection electrical signal into a second digital quantity, comparing it with a preset second threshold value, and outputting a detection result signal according to the comparison result; The main control module is further configured to lower the second threshold when the second digital value is lower than a preset third threshold.

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