A calibration method for photoelectric characteristic difference of photoelectric sensor

Abstract

The present invention discloses a method for calibrating the photoelectric characteristic difference of a photoelectric sensor, which is characterized by comprising the steps of: S1, respectively adjusting the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor under the condition that the specific calibration environment and the illumination environment are consistent, so that the electrical signal values ​​output by each photoelectric sensor are consistent; S2, respectively storing the PWM drive values ​​when the signal values ​​output by each photoelectric sensor are consistent; S3, when driving and using each photoelectric sensor, calling the stored PWM drive value of each photoelectric sensor, and driving the photoelectric sensor under the drive of the PWM drive value. This method can eliminate or reduce the photoelectric characteristic difference of the photoelectric sensor, and improve the detection accuracy and detection consistency of the sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor calibration, and in particular to a method for calibrating photoelectric characteristic differences of a photoelectric sensor. Background Art

[0002] At present, no matter whether it is through-beam or reflective type, the photoelectric sensors cannot guarantee the consistency of the photoelectric characteristics of each sensor in mass production, resulting in misjudgment or unusability in some high-precision application environments. In later use, the photoelectric sensors will also be affected by structural differences, high temperature, humidity, oxidation, dust and contamination, etc., resulting in differences in photoelectric characteristics, which in turn leads to a decrease in the detection accuracy of the photoelectric sensors. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a method for calibrating the differences in photoelectric characteristics of photoelectric sensors, which can quickly and effectively calibrate the problem of reduced sensor detection accuracy caused by slight differences in individual photoelectric characteristics in mass production, or differences in photoelectric characteristics caused by high temperature, humidity, oxidation, dust contamination and other factors.

[0004] The technical solution of the present invention is:

[0005] A method for calibrating the difference in photoelectric characteristics of a photoelectric sensor, characterized in that it comprises the steps of:

[0006] S1, when a specific calibration environment and an illumination environment are consistent, respectively adjust the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor so that the value of the electrical signal output by each photoelectric sensor is consistent;

[0007] S2, respectively stores the PWM driving value when the signal value output by each photoelectric sensor is consistent;

[0008] S3, when driving and using each photoelectric sensor, calling the stored PWM driving value of each photoelectric sensor, and driving the photoelectric sensor under the driving of the PWM driving value.

[0009] Furthermore, the specific calibration environment includes an environment with specific temperature, dust-free and relatively fixed lighting environment.

[0010] Furthermore, the consistent illumination environment includes the consistent illumination of the substance directed to the photodiode in the photoelectric sensor, and the consistent absolute distance of the illuminated substance relative to the illuminated photodiode.

[0011] Furthermore, in S1, the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor is adjusted respectively, so that the signal value output by each photoelectric sensor is consistent. The microprocessor MCU outputs the PWM signal to the two ends of the light-emitting diode of each photoelectric sensor, and inputs the PWM signal to each photoelectric sensor.

[0012] Furthermore, in S1, making the signal value output by each photoelectric sensor consistent is achieved by receiving the analog signal value at the output end of the photoelectric sensor, converting the analog signal output into a numerical signal, and then automatically judging and automatically adjusting the output PWM signal by the microprocessor MCU.

[0013] Furthermore, the microprocessor MCU is integrated with an analog-to-digital conversion module, and the analog signal output by the photoelectric sensor is directly and automatically collected and judged by the analog-to-digital conversion module of the microprocessor MCU, and the duty cycle of the output PWM signal is automatically adjusted by the microprocessor MCU.

[0014] The beneficial effects of the present invention are as follows: the method adjusts the luminous intensity of the light-emitting diode of the photoelectric sensor by adjusting the PWM duty cycle, and then collects the numerical value of the receiving end of the photoelectric sensor to make the numerical value of the receiving end of the photoelectric sensor consistent, and stores and uses the numerical value, which can eliminate or reduce the difference in the photoelectric characteristics of the photoelectric sensor and improve the detection accuracy and detection consistency of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a flow chart of a method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0017] like Figure 1 As shown, a method for calibrating the difference in photoelectric characteristics of a photoelectric sensor is characterized by comprising the steps of:

[0018] S1, when the specific calibration environment and the illumination environment are consistent, respectively adjust the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor so that the value of the electrical signal output by each photoelectric sensor is consistent, where the consistency of the electrical signal value means the consistency of the voltage value of the electrical signal;

[0019] Among them, the specific calibration environment includes a specific temperature and humidity, dust-free and relatively fixed lighting environment, especially pay attention to avoid the influence of external sunlight and light, and the illumination environment is consistent, including the material irradiated by the photodiode in the photoelectric sensor, and the absolute distance of the irradiated material relative to the irradiated photodiode is consistent. Avoid errors in the calibration value caused by differences in photoelectric characteristics caused by external structural differences, light intensity, temperature, humidity, oxidation, dust contamination and other factors.

[0020] In addition, the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor is adjusted respectively so that the value of the electrical signal output by each photoelectric sensor is consistent. The microprocessor MCU outputs the PWM signal to the two ends of the light-emitting diode of each photoelectric sensor, and inputs the PWM signal to each photoelectric sensor.

[0021] S2, respectively stores the PWM driving value when the electrical signal value output by each photoelectric sensor is consistent, and saves the specific PWM value in FLASH to save the calibration value when power is off, avoiding secondary calibration or repeated calibration operation;

[0022] S3, when driving and using each photoelectric sensor, the stored PWM driving value of each photoelectric sensor is called, and the photoelectric sensor is driven by the PWM driving value. This ensures that the photoelectric characteristics of each photoelectric sensor are consistent, and achieves high-precision detection of the photoelectric sensor. In the future, the calibration function can be integrated into the product and opened to users, which can improve the accuracy of real-time detection of the product and solve equipment failures caused by sudden environmental changes or dust to a certain extent.

[0023] It should be further explained that, in one embodiment, making the signal value output by each photoelectric sensor consistent in S1 is achieved by receiving the analog signal value at the output end of the photoelectric sensor, converting the analog signal output into a digital signal, and then automatically judging and automatically adjusting the output PWM signal by the microprocessor MCU.

[0024] It should be further explained that, in one embodiment, the microprocessor MCU is integrated with an analog-to-digital conversion module, and the analog signal output by the photoelectric sensor is directly and automatically collected and judged by the analog-to-digital conversion module of the microprocessor MCU, and the duty cycle of the output PWM signal is automatically adjusted by the microprocessor MCU.

[0025] The above embodiments only express the concentrated implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A method for calibrating the difference in photoelectric characteristics of a photoelectric sensor, characterized in that: Includes steps: S1, when a specific calibration environment and an illumination environment are consistent, respectively adjust the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor so that the value of the electrical signal output by each photoelectric sensor is consistent; S2, respectively stores the PWM driving value when the signal value output by each photoelectric sensor is consistent; S3, when driving and using each photoelectric sensor, calling the stored PWM driving value of each photoelectric sensor, and driving the photoelectric sensor under the driving of the PWM driving value; The illumination environment is consistent, including the material illuminated by the photodiode in the photoelectric sensor, and the absolute distance of the illuminated material relative to the illuminated photodiode is consistent.

2. The method for calibrating the photoelectric characteristic difference of a photoelectric sensor according to claim 1, characterized in that: The specific calibration environment includes a specific temperature, dust-free and relatively fixed lighting environment.

3. The method for calibrating the photoelectric characteristic difference of a photoelectric sensor according to claim 1, characterized in that: In S1, the duty cycle of the PWM drive signal input to the input end of each photoelectric sensor in the batch sensor is adjusted respectively, so that the signal value output by each photoelectric sensor is consistent. The PWM signal is output to the two ends of the light-emitting diode of each photoelectric sensor through the microprocessor MCU, and the PWM signal is input to each photoelectric sensor.

4. The method for calibrating the photoelectric characteristic difference of a photoelectric sensor as claimed in claim 3, characterized in that: In S1, making the signal value output by each photoelectric sensor consistent is achieved by receiving the analog signal value of the output end of the photoelectric sensor, converting the analog signal output into a numerical signal, and then automatically judging and automatically adjusting the output PWM signal through the microprocessor MCU.

5. The method for calibrating the photoelectric characteristic difference of a photoelectric sensor as claimed in claim 4, characterized in that: The microprocessor MCU is integrated with an analog-to-digital conversion module. The analog signal output by the photoelectric sensor is directly and automatically collected and judged by the analog-to-digital conversion module of the microprocessor MCU, and the duty cycle of the output PWM signal is automatically adjusted by the microprocessor MCU.

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