Background suppression type photoelectric sensor system

Abstract

The invention discloses a background suppression type photoelectric sensor system, and the system comprises a light transmitting module which is used for receiving a pulse signal and transmitting a light signal to a target region; the light receiving module is used for converting the light signal reflected from the target area into a first voltage signal and outputting the first voltage signal; the voltage amplification module is used for amplifying the first voltage signal and generating and outputting a second voltage signal; the gating module is used for receiving the pulse signal and the second voltage signal, and outputting the second voltage signal when the pulse signal is at a high level; and the main control module is used for outputting a pulse signal, receiving the second voltage signal output by the gating module and generating an indication signal according to the second voltage signal. According to the photoelectric sensor system provided by the invention, the main control module can judge whether the target detection object exists in the target area only when the pulse signal is at the high level, so that the influence of stray light on the photoelectric sensor is effectively reduced, and the anti-interference capability of the photoelectric sensor is improved.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a background suppression type photoelectric sensor system. Background Art

[0002] Background suppression photoelectric sensors often face the challenge of stray light interference. Because the optical signal received by the photoelectric sensor includes not only the useful photocurrent generated by the sensor's own light source, but also the photocurrent generated by various stray lights in the environment (such as indoor lighting, sunlight, etc.). These stray lights may be mixed with the useful photocurrent, causing the useful light signal to be interfered with. In some cases, especially when the ambient light intensity is very high, the interference current caused by the stray light may even exceed the current generated by the sensor's own light source, which will directly affect the normal operation of the photoelectric sensor.

[0003] Traditional background suppression photoelectric sensors usually convert the received light signal directly into an electrical signal, then enhance the signal through an amplifier circuit, and finally provide it to the subsequent circuit for sampling and judgment. However, due to the lack of effective signal separation means, any interference signal received by the sensor during the entire pulse width modulation (PWM) signal cycle may affect the final signal acquisition. Therefore, the interference signal may change the intensity of the useful signal, causing the sensor to have problems such as shortened distance or misjudgment during detection, and in extreme cases, it may even cause the sensor to fail to detect the target normally. In order to overcome these problems, new methods need to be developed to reduce the impact of stray light on the performance of photoelectric sensors. Summary of the invention

[0004] In view of the above problems, the present application provides a background suppression type photoelectric sensor system to solve the above technical problems.

[0005] In a first aspect, the present application provides a background suppression type photoelectric sensor system, comprising:

[0006] An optical transmission module, used for receiving a pulse signal to transmit an optical signal to a target area;

[0007] A light receiving module, used for converting a light signal reflected from a target area into a first voltage signal for output;

[0008] A voltage amplification module, used to amplify the first voltage signal and generate a second voltage signal output;

[0009] A gating module, used for receiving a pulse signal and a second voltage signal, and outputting the second voltage signal when the pulse signal is at a high level;

[0010] The main control module is used to output a pulse signal and to receive a second voltage signal output by the selection module, and to generate an indication signal according to the second voltage signal, wherein the indication signal is used to indicate whether a target detection object exists in a target area.

[0011] The background suppression type photoelectric sensor system provided in the present application generates a second voltage signal by receiving a pulse signal and a voltage amplification module, and only when the pulse signal is at a high level will the second voltage signal be output to the main control module. In this way, the main control module will determine whether there is a target detection object in the target area only when the pulse signal is at a high level, thereby effectively reducing the influence of stray light on the photoelectric sensor and improving the anti-interference ability of the photoelectric sensor.

[0012] 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

[0013] 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.

[0014] Figure 1 A module schematic diagram of a photoelectric sensor system provided in an embodiment of the present application is shown.

[0015] Figure 2 A structural schematic diagram of a gating module provided in an embodiment of the present application is shown.

[0016] Figure 3 Another structural schematic diagram of the analog switch unit provided in an embodiment of the present application is shown.

[0017] Figure 4 A module schematic diagram of the optical transmission module provided in an embodiment of the present application is shown.

[0018] Figure 5 A structural schematic diagram of an optical transmission module provided in an embodiment of the present application is shown.

[0019] Figure 6 A module schematic diagram of an optical receiving module provided in an embodiment of the present application is shown.

[0020] Figure 7 A structural schematic diagram of an optical receiving module provided in an embodiment of the present application is shown.

[0021] Figure 8 A module schematic diagram of a voltage amplification module provided in an embodiment of the present application is shown.

[0022] Fig. 9 A structural schematic diagram of a voltage amplification module provided in an embodiment of the present application is shown.

[0023] Fig.10 Another module schematic diagram of the photoelectric sensor system provided in an embodiment of the present application is shown.

[0024] Fig.11 A schematic diagram of a power conversion module provided in an embodiment of the present application is shown.

[0025] Fig.12 Another module schematic diagram of the photoelectric sensor system provided in an embodiment of the present application is shown.

[0026] Fig.13 A schematic diagram of a photoelectric sensor provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] In the circuit structure provided in the embodiments of the present application, the nodes do not represent actual existing components, but represent the junction points of related couplings in the circuit diagram, that is, these nodes are nodes formed by the equivalent junction points of related couplings in the circuit diagram.

[0032] 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.

[0033] The present application embodiment provides a background suppression type photoelectric sensor system. Figure 1 The module schematic diagram of the photoelectric sensor system provided in the embodiment of the present application is shown as follows: Figure 1 As shown, the photoelectric sensor system includes a light transmitting module, a light receiving module, a voltage amplifying module, a gating module and a main control module.

[0034] Among them, the light emitting module is used to receive a pulse signal to emit a light signal to the target area, the light receiving module is used to convert the light signal reflected from the target area into a first voltage signal output, the voltage amplification module is used to amplify the first voltage signal, generate a second voltage signal output, the gating module is used to receive the pulse signal and the second voltage signal, when the pulse signal is at a high level, output the second voltage signal, the main control module is used to output the pulse signal, and for receiving the second voltage signal output by the gating module, generating an indication signal according to the second voltage signal, the indication signal is used to indicate whether there is a target detection object in the target area. Optionally, when there is an interfering light source, the light receiving module may also receive light signals from the interfering light sources, these interfering light sources may cause the useful signal (light signal from the target area) to rise or fall, and in severe cases may even drown out the useful signal, thereby causing the sensor to misdetect, therefore, the embodiment of the present application sets the gating module, only when the pulse signal output by the main control module is at a high level, the electrical signal converted by the light receiving module will be received by the main control module, so as to reduce the interference of the interfering light source to the sensor.

[0035] 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.

[0036] The background suppression type photoelectric sensor system provided in the embodiment of the present application generates a second voltage signal by receiving a pulse signal and a voltage amplification module, and only when the pulse signal is at a high level will the second voltage signal be output to the main control module. In this way, the main control module will determine whether there is a target detection object in the target area only when the pulse signal is at a high level, thereby effectively reducing the influence of stray light on the photoelectric sensor and improving the anti-interference ability of the photoelectric sensor.

[0037] In some embodiments, Figure 2 A schematic diagram of the structure of the gating module provided in the embodiment of the present application is shown. Figure 2 As shown, in the photoelectric sensor system provided by the embodiment of the present application, the selection module includes an analog switch unit, the signal input end (A) of the analog switch unit is connected to the voltage amplifier module to receive the second voltage signal output by the voltage amplifier module, the first signal output end (B1) of the analog switch unit is connected to the main control module to output the second voltage signal to the main control module, so that the main control module determines whether there is a target detection object in the target area according to the second voltage signal, the second signal output end (B2) of the analog switch unit is grounded, so that when the pulse signal is at a low level, the second voltage signal is discharged to the ground to avoid interference with the light source, the control end (SELECT) of the analog switch unit is connected to the main control module to receive the pulse signal output by the main control module, so that the analog switch unit controls the second voltage signal to be output from the first signal output end when the pulse signal is at a high level, and controls the second voltage signal to be output from the second signal output end when the pulse signal is at a low level.

[0038] Optionally, the analog switch unit further includes a power input terminal and a ground terminal, which are used to respectively connect to a power supply circuit and a ground of the photoelectric sensor system.

[0039] It can be understood that in the embodiments of the present application, there is no limitation on the specific structure of the analog switch unit. For example, the analog switch unit can be set to an existing analog switch device / chip, or it can be set to a circuit with gating capability built by a designer. Specifically, the analog switch unit can be any circuit module that can realize the functions described in the above embodiments.

[0040] The background suppression type photoelectric sensor system provided in the embodiment of the present application outputs the second voltage signal to the main control module through the analog switch unit. The analog switch unit will choose to output the second voltage signal to the main control module only when the pulse signal is at a high level. In this way, the main control module will determine whether there is a target detection object in the target area only when the pulse signal is at a high level, thereby effectively reducing the influence of stray light on the photoelectric sensor and improving the anti-interference ability of the photoelectric sensor.

[0041] In some embodiments, Figure 3Another structural schematic diagram of the analog switch unit provided in the embodiment of the present application is shown. Figure 3 As shown, the analog switch unit further includes a first resistor R1, a first end of the first resistor R1 is connected to the second signal output end (B2) of the analog switch unit, and a second end of the first resistor unit is grounded. Optionally, the first resistor R1 is used as a pull-down resistor, and when the pulse signal is at a low level, the interference signal integrated by the interference light is pulled down and discharged to the ground, thereby avoiding affecting the useful signal.

[0042] In some embodiments, Figure 4 A schematic diagram of a light transmitting module provided in an embodiment of the present application is shown. Figure 4 As shown, the optical transmission module includes a laser diode LD, a photodiode PD, a first filtering unit, a first switching unit, a second switching unit, a first voltage dividing unit, a second voltage dividing unit, a power regulating unit, a first current limiting unit and an anti-reverse diode unit D1.

[0043] The anode of the laser diode LD is used to receive the power supply voltage V5P0 through the first filtering unit, and the cathode is connected to the first switch unit through the first current limiting unit. The cathode of the photodiode PD is used to receive the power supply voltage V5P0 through the first filtering unit, and the anode is connected to the second switch unit. The control end of the first switch unit is connected to the second switch unit, and is connected to the main control module through the first voltage divider unit to receive the pulse signal. The first end is connected to the laser diode LD through the first current limiting unit, and the second end is grounded. The control end of the second switch unit is connected to the anode of the photodiode, and is connected to the power adjustment unit through the second voltage divider unit. The first end is connected to the first switch unit, and the second end is grounded. The power adjustment unit is used to adjust the voltage divided by the second voltage divider unit output to the second switch unit. The anode of the anti-reverse diode unit D1 is connected to the second switch unit through the first current limiting unit, and the cathode of the anti-reverse diode unit D1 is used to receive the power supply voltage V5P0 through the first filtering unit. The power adjustment unit, the first filtering unit, the first voltage divider unit, and the second voltage divider unit are also grounded.

[0044] Among them, the first filtering unit is used to filter the power supply voltage V5P0, the first voltage dividing unit and the second voltage dividing unit are used to provide bias voltages for the first switch unit and the second switch unit respectively, the first current limiting unit is used to limit current, and the anti-reverse diode unit is used to prevent current reverse.

[0045] Optionally, in the background suppression type photoelectric sensor system provided by the embodiment of the present application, when the pulse signal output by the main control module is at a low level, the first switch unit is not turned on, so that the laser diode does not emit light; when the pulse signal output by the main control module is at a high level, the first switch unit is turned on, so that the laser diode emits light. Optionally, after the first switch unit is turned on, the greater the light-emitting power of the laser diode, the greater the photocurrent of the photodiode. When the photocurrent reaches a threshold value, the second switch unit is turned on, so that the light-emitting power of the laser diode is reduced. When the light-emitting power of the laser diode decreases, the second switch unit is disconnected, so that the light-emitting power of the laser diode increases again. The photoelectric sensor system provided by the embodiment of the present application enables the optical power to be constantly in a dynamic equilibrium state.

[0046] It can be understood that the embodiments of the present application do not limit the specific structures of the above-mentioned first filtering unit, first voltage dividing unit, second voltage dividing unit, power adjustment unit, and first current limiting unit, as long as they can achieve the functions described in the above-mentioned embodiments.

[0047] In some embodiments, Figure 5 A schematic diagram of the structure of the optical transmission module provided in the embodiment of the present application is shown. Figure 5 As shown, the first switch unit includes an NPN transistor Q1, and the second switch unit includes an NPN transistor Q2. The first current limiting unit includes a resistor RL, the first end of the resistor RL is respectively connected to the cathode of the laser diode LD and the anode of the anti-reverse diode D1, and the second end is connected to the first end of the first switch unit. The first voltage dividing unit includes a second resistor R2 and a third resistor R3, the first end of the second resistor R2 is connected to the main control module to receive the pulse signal, the second end of the second resistor R2 is respectively connected to the first end of the first switch unit and the third resistor R3, and the second end of the third resistor R3 is grounded. The second voltage dividing unit includes a fourth resistor R4 and a fifth resistor R5, the first end of the fourth resistor R4 is connected to the second switch unit, the second end of the fourth resistor R4 is respectively connected to the first end of the power adjustment unit and the fifth resistor R5, and the second end of the fifth resistor is grounded. The power adjustment unit includes a potentiometer RT, the sliding end of the potentiometer RT is respectively connected to the fourth resistor R4 and the fifth resistor R5, the first end is suspended, and the second end is grounded. The first filtering unit includes a sixth resistor R6, a first capacitor C1 and a second capacitor C2. The first end of the sixth resistor R6 is used to receive the power supply voltage V5P0. The second end of the sixth resistor R6 is respectively connected to the first end of the first capacitor C1, the first end of the second capacitor C2, the laser diode LD and the photodiode PD. The second end of the first capacitor C1 and the second end of the second capacitor C2 are both grounded.

[0048] The photoelectric sensor system provided in the embodiment of the present application realizes dynamic control of the power of the laser diode by using only two switch units and basic components such as resistors and capacitors. Compared with the traditional laser driving circuit that needs to use operational amplifiers and transistors to realize dynamic control of the laser diode, the photoelectric sensor provided in the embodiment of the present application reduces the circuit cost.

[0049] In some embodiments, Figure 6 A schematic diagram of a light receiving module provided in an embodiment of the present application is shown. Figure 6 As shown, the optical receiving module includes a dual photodiode unit U1, a second filtering unit, a first sampling unit and a second sampling unit. The two cathodes of the dual photodiode unit U1 are used to receive the power supply voltage V5P0 through the second filtering unit, and the two anodes are connected to the voltage amplification module and grounded through the first sampling unit and the second sampling unit, respectively, so as to convert the optical signal reflected by the target area into two electrical signals (i.e., the first voltage signal) through the dual photodiode unit.

[0050] It can be understood that the embodiments of the present application do not limit the specific structures of the second filtering unit, the first sampling unit and the second sampling unit, as long as they can achieve the functions described in the embodiments.

[0051] For example, Figure 7 A schematic diagram of the structure of the optical receiving module provided in the embodiment of the present application is shown. Figure 7 As shown, the second filtering unit is an RC filtering circuit composed of a seventh resistor R7 and a third capacitor C3, the first sampling unit includes an eighth resistor R8, and the second sampling unit includes a ninth resistor R9.

[0052] In some embodiments, Figure 8 A schematic diagram of a voltage amplification module provided in an embodiment of the present application is shown in FIG. Figure 8 As shown, the voltage amplification module includes a third filtering unit, a differential amplification unit, a fourth filtering unit and an inverting amplification unit. The third filtering unit is used to receive a first voltage signal (the first voltage signal is Figure 6 The two electrical signals output by the optical receiving module shown in the figure) are used to filter the first voltage signal, and the differential amplifier unit is used to filter the filtered first voltage signal (the first voltage signal is Figure 6 The two electrical signals output by the optical receiving module shown in the figure are differentially amplified to generate a third voltage signal output; the fourth filtering unit is used to filter the third voltage signal, and the inverting amplifying unit is used to invert the filtered third voltage signal to generate a second voltage signal output.

[0053] The photoelectric sensor system provided in the embodiment of the present application performs a first-stage differential amplification on the two electrical signals (i.e., the first voltage signal) converted by the optical receiving module through a differential amplifier unit to generate a third voltage signal, and performs a second-stage reverse amplification on the third voltage signal obtained by the first-stage amplification through an inverting amplifier unit to generate a second voltage signal. In this way, even if the different amounts of light reflected by the detection objects of different colors cause different photocurrents generated by the photoelectric receiving tube, the two electrical signals generated by the dual photodiode unit will increase or decrease at the same time, so that the sensor will not cause changes in the detection distance due to the strong or weak light reflection capabilities of the detection objects of different colors, thereby achieving the background suppression effect.

[0054] It is understandable that the embodiments of the present application do not limit the specific structures of the differential amplifier unit and the inverting amplifier unit as long as they can achieve the functions described in the embodiments.

[0055] For example, Fig. 9 A schematic diagram of the structure of the voltage amplification module provided in the embodiment of the present application is shown. Fig. 9 As shown, the voltage amplifier module (referring to Fig. 9 In the circuit within the dotted line), the third filtering unit includes a fourth capacitor C4 and a fifth capacitor C5 connected to the two anodes of the dual photodiode unit in the optical receiving module to filter the two received electrical signals (i.e., the first electrical signal) respectively, and the inverting differential amplification unit includes a first operational amplifier A1, a sixth capacitor C6, a seventh capacitor C7, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14 and a fifteenth resistor R15.

[0056] The inverting input terminal of the first operational amplifier A1 is connected to an anode of the dual photodiode unit through the tenth resistor R10 and the fourth capacitor C4, and is connected to the output terminal of the first operational amplifier A1 through the eleventh resistor R11; the non-inverting input terminal of the first operational amplifier A1 is connected to the other anode of the dual photodiode unit through the fifth capacitor C5, and is grounded through the twelfth resistor R12 and the sixth capacitor C6, and the connection node between the sixth capacitor C6 and the twelfth resistor R12 is also grounded through the fourteenth resistor R14 and the fifteenth resistor R15. The ground terminal of the first operational amplifier A1 is grounded, the power supply terminal of the first operational amplifier A1 receives the power supply voltage V5P0, and is grounded through the seventh capacitor C7, the seventh capacitor C7 is also grounded through the thirteenth resistor R13, the fourteenth resistor R14 and the fifteenth resistor R15, and the output terminal of the first operational amplifier A1 is connected to the inverting amplification unit.

[0057] The fourth filtering unit includes an eighth capacitor C8 to filter the third voltage signal output by the differential amplifier unit, and the inverting amplifier unit includes a second operational amplifier A2, a ninth capacitor C9, a tenth capacitor C10, an eleventh capacitor C11, a sixteenth resistor R16, a seventeenth resistor R17 and an eighteenth resistor R18.

[0058] Among them, the inverting input terminal of the second operational amplifier A2 is connected to the output terminal of the first operational amplifier A1 through the sixteenth resistor R16 and the eighth capacitor C8, and is connected to the output terminal of the second operational amplifier A2 through the ninth capacitor C9 and the seventeenth resistor R17 respectively, the non-inverting input terminal of the second operational amplifier A2 is grounded through the tenth capacitor C10, and the output terminal of the second operational amplifier is connected to the signal input terminal (A) of the selection module through the eighteenth resistor R18, and is grounded through the eleventh capacitor C11.

[0059] In some embodiments, Fig.10 Another module schematic diagram of the photoelectric sensor system provided in the embodiment of the present application is shown in FIG. Fig.10 As shown, the photoelectric sensor system also includes a power conversion module, which is used to connect to the power supply and step down the power supply voltage to convert it into a power supply voltage V5P0 to power the optical transmitting module, optical receiving module, voltage amplifying module, gating module, and main control module respectively.

[0060] It is understandable that the embodiments of the present application do not limit the specific structure of the above-mentioned power conversion module, as long as it can achieve the functions described in the above-mentioned embodiments. For example, the power conversion module can achieve power supply voltage reduction by using a step-down chip.

[0061] In some embodiments, the power conversion module provided in the embodiments of the present application is a digital sensor output driver integrated with a low voltage difference linear regulator. In addition to being used to step down the power supply voltage to power each module, the digital sensor output driver integrated with the low voltage difference linear regulator can also be used to receive the first level signal and the second level signal output by the two IO ports of the main control module. When the first level signal and the second level signal are high level, an NPN signal is output. When the first level signal is high level and the second level signal is low level, a PNP signal is output.

[0062] Optionally, taking the digital sensor output driver model TIOS1015DMWR as an example, Fig.11 A schematic diagram of a power conversion module provided in an embodiment of the present application is shown. Fig.11As shown, this model of digital sensor output driver integrates a low voltage drop linear regulator, the VCC pin is configured to receive the power supply voltage Vin through the current limiting resistor element R19, and is also grounded through the filter capacitor element C12, the VCC_IN / OUT pin is configured to output the power supply voltage V5P0 (that is, the power supply voltage is converted to a 5V power supply voltage), and is grounded through the capacitor element C13, thereby realizing the power supply voltage Vin is stepped down to the power supply voltage V5P0 to power each module.

[0063] like Fig.11 As shown, in the digital sensor output driver of model TIOS1015DMWR, the IN pin and the EN pin are configured to be connected to the main control module respectively to receive the first level signal and the second level signal respectively. According to the first level signal and the second level signal, the OUT pin outputs the NPN signal and the PNP signal, thereby realizing the configuration of the digital sensor output driver of this model to output the NPN signal or the PNP signal. Specifically, the digital sensor output driver of this model includes two customizable IO ports (IN pin and EN pin), and the two IO ports are set to receive the first level signal and the second level signal from the main control module (such as MCU, single-chip microcomputer, etc.), respectively. When the first level signal and the second level signal are high, the digital sensor output driver of this model outputs the NPN signal through the OUT pin. When the first level signal is high and the second level signal is low, the digital sensor output driver of this model outputs the PNP signal through the OUT pin. It should be clear that the first and second relationship terms in the embodiments of the present application are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0064] It is understandable that if Fig.11 As shown, the power conversion module provided in the embodiment of the present application is only applied to the pins described in the above embodiment, and the embodiment of the present application does not limit the other pins of the digital sensor output driver model TIOS1015DMWR. The connection relationship of the pins can be set according to the requirements during circuit design. For example, Fig.11As shown, in the digital sensor output driver of model TIOS1015DMWR, the embodiment of the present application configures the NFAULT pin (the TIOS1015DMWR model digital sensor output driver is usually used to indicate the fault status of the driver) to be grounded through the current limiting resistor element R20, configures the ILIM_ADJ pin (the TIOS1015DMWR model digital sensor output driver is usually used to adjust or set the maximum output current limit of the driver) to be grounded through the current limiting resistor element R21, configures the NC0 pin (undefined pin) to be unconnected, configures the NC1 (undefined pin) pin to be grounded, and configures the GND pin to be grounded.

[0065] In some embodiments, Fig.12 Another module schematic diagram of the photoelectric sensor system provided in the embodiment of the present application is shown. Fig.12 As shown, the photoelectric sensor system also includes an indication module, which is connected to the main control module and is used to receive the indication signal, and indicates that the target detection object exists in the target area when the indication signal is a first level, and indicates that the target detection object does not exist in the target area when the indication signal is a second level.

[0066] 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.

[0067] The background suppression type photoelectric sensor system provided in the embodiment of the present application is used to prepare a background suppression type photoelectric sensor. Optionally, the embodiment of the present application provides a background suppression type photoelectric sensor. Fig.13 A schematic diagram of a photoelectric sensor provided in an embodiment of the present application is shown. Fig.13 As shown, the photoelectric sensor includes a housing 100 and a photoelectric sensor system, a transmitting lens 110 and a receiving lens 120 disposed in the housing 100 .

[0068] In some embodiments, the background suppression type photoelectric sensor system provided in the embodiments of the present application is used to prepare a laser background suppression type photoelectric sensor.

[0069] 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 background suppression type photoelectric sensor system, characterized in that: include: An optical transmission module, used for receiving a pulse signal to transmit an optical signal to a target area; A light receiving module, used for converting the light signal reflected from the target area into a first voltage signal for output; A voltage amplification module, used to amplify the first voltage signal and generate a second voltage signal for output; A gating module, configured to receive the pulse signal and the second voltage signal, and output the second voltage signal when the pulse signal is at a high level; The main control module is used to output the pulse signal and receive the second voltage signal output by the selection module, and generate an indication signal according to the second voltage signal, wherein the indication signal is used to indicate whether the target detection object exists in the target area.

2. The background suppression type photoelectric sensor system according to claim 1, characterized in that: The gating module includes an analog switch unit; The signal input end of the analog switch unit is connected to the voltage amplification module to receive the second voltage signal; The first signal output terminal of the analog switch unit is connected to the main control module to output the second voltage signal to the main control module, and the second signal output terminal of the analog switch unit is grounded; The control end of the analog switch unit is connected to the main control module to receive the pulse signal output by the main control module, control the second voltage signal to be output from the first signal output end when the pulse signal is at a high level, and control the second voltage signal to be output from the second signal output end when the pulse signal is at a low level.

3. The background suppression type photoelectric sensor system according to claim 2, characterized in that: The analog switch unit further includes a first resistor; A first end of the first resistor is connected to the second signal output end of the analog switch unit, and a second end of the first resistor is grounded.

4. The background suppression type photoelectric sensor system according to claim 1, characterized in that: The optical transmission module includes a laser diode, a photodiode, a first filtering unit, a first switching unit, a second switching unit, a first voltage dividing unit, a second voltage dividing unit, a power adjustment unit, a first current limiting unit and an anti-reverse diode unit; The anode of the laser diode is used to receive the power supply voltage through the first filter unit, and the cathode is connected to the first switch unit through the first current limiting unit; The cathode of the photodiode is used to receive the supply voltage through the first filtering unit, and the anode is connected to the second switch unit; The control end of the first switch unit is connected to the second switch unit, and is connected to the main control module through the first voltage divider unit to receive the pulse signal, the first end is connected to the laser diode through the first current limiting unit, and the second end is grounded; The control end of the second switch unit is connected to the anode of the photodiode and is connected to the power adjustment unit through the second voltage divider unit, the first end is connected to the first switch unit, and the second end is grounded; The power adjustment unit is used to adjust the divided voltage output by the second voltage dividing unit to the second switch unit; The anode of the anti-reverse diode is connected to the second switch unit through the first current limiting unit, and the cathode of the anti-reverse diode is used to receive the supply voltage through the first filtering unit; The first filtering unit, the first voltage dividing unit and the second voltage dividing unit are also grounded.

5. The background suppression type photoelectric sensor system according to claim 4, characterized in that: The first voltage dividing unit includes a second resistor and a third resistor; The first end of the second resistor is connected to the main control module to receive the pulse signal, the second end of the second resistor is respectively connected to the first switch unit and the first end of the third resistor, and the second end of the third resistor is grounded; The second voltage dividing unit includes a fourth resistor and a fifth resistor; The first end of the fourth resistor is connected to the second switch unit, the second end of the fourth resistor is connected to the power adjustment unit and the first end of the fifth resistor respectively, and the second end of the fifth resistor is grounded; The power adjustment unit includes a potentiometer; The sliding end of the potentiometer is connected to the fourth resistor and the fifth resistor respectively, the first end is suspended, and the second end is grounded; The first filtering unit includes a sixth resistor, a first capacitor and a second capacitor; The first end of the sixth resistor is used to receive the supply voltage, the second end of the sixth resistor is respectively connected to the first end of the first capacitor, the first end of the second capacitor, the laser diode and the photodiode, and the second end of the first capacitor and the second end of the second capacitor are both grounded.

6. The background suppression type photoelectric sensor system according to claim 1, characterized in that: The optical receiving module includes a dual photodiode unit, a second filtering unit, a first sampling unit and a second sampling unit; The two cathodes of the dual photodiode unit are used to receive the power supply voltage through the second filtering unit, and the two anodes are connected to the voltage amplification module and are grounded through the first sampling unit and the second sampling unit respectively.

7. The background suppression type photoelectric sensor system according to claim 1, characterized in that: The voltage amplification module comprises: a third filtering unit, configured to receive the first voltage signal to perform filtering processing on the first voltage signal; a differential amplification unit, connected to the third filtering unit, and configured to differentially amplify the first voltage signal to generate a third voltage signal for output; a fourth filtering unit, configured to receive the third voltage signal to filter the third voltage signal; The inverting amplifier unit is connected to the fourth filtering unit and is used to invert and amplify the second voltage signal to generate the second voltage signal for output.

8. The background suppression type photoelectric sensor system according to claim 1, characterized in that: Also includes: The power conversion module is used to connect the power supply, step down the power supply voltage, and convert it into a power supply voltage to respectively power the optical transmitting module, the optical receiving module, the voltage amplifying module, the gating module, and the main control module.

9. The background suppression type photoelectric sensor system according to claim 8, characterized in that: The power conversion module includes: a digital sensor output driver with an integrated low-voltage difference linear regulator, and the digital sensor output driver with an integrated low-voltage difference linear regulator is also used to receive a first level signal and a second level signal output by the main control module, and output an NPN signal when the first level signal and the second level signal are both high level, and output a PNP signal when the first level signal is high level and the second level signal is low level.

10. The background suppression type photoelectric sensor system according to claim 1, characterized in that: Also includes: The indication module is connected to the main control module and is used to receive the indication signal, and indicates that the target detection object exists in the target area when the indication signal is at a first level, and indicates that the target detection object does not exist in the target area when the indication signal is at a second level.

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