As we all know, sensors have been widely used in human consumption and life. Especially for high-definition products, various sensors are needed to monitor and control various parameters in the consumption process, so that the equipment works normally or optimally. State and bring the product to the best quality. Therefore, it can be said that without many excellent sensors, modern consumption will lose its roots. In medicine, sensors can better analyze the cause and get a good treatment plan. In the research discussion, the sensor has a prominent position. In many areas, the sensory and simple sensors are basically unable to obtain accurate data. It is necessary to use a high-precision sensor to perform the analysis. The photosensitive receiving tube is a light-sensitive component that uses light. Sensors that convert signals into electrical signals have a very important position in automatic control and non-electrical electronic technology because of their non-contact, fast response and reliable performance.
(1) Sensitive component: It can directly sense the measured non-electricity and convert it into other physical quantities that have a positive relationship with the measured non-electricity according to certain rules.
(2) Conversion device (also called converter, sensor device): converts the non-electrical physical quantity (such as light intensity, etc.) output by the sensitive component into circuit parameters.
(3) Signal conditioning (conversion) circuit: stop the amplification, calculation, disposal, etc. of the electrical signal outputted by the conversion device to obtain a useful electrical signal for visualization, recording, disposal and control.
(4) Auxiliary power supply: Its role is to provide energy. Some sensors require an external power supply; some sensors do not require an external power supply, such as a piezoelectric sensor.
The role of the sensor
Today's information technology is reactionary. The employer feels that the organ can't get accurate data, and at the same time, it has to stop for many things that can't be sensed by the organ. The sensor is an alternative to the human body to get information and data. medium.
In industrial consumption, high-precision products are required to support various sensors to monitor and control various parameters in the consumption process, to make the equipment work in a normal state or in an optimal state, and to achieve the best quality of the product. Therefore, it can be said that without many excellent sensors, modern consumption will lose its roots.
The photosensitive receiving tube is a sensor that converts an optical signal into an electrical signal by using a photosensitive element, and its sensitive wavelength is near the visible wavelength, including the infrared wavelength and the ultraviolet wavelength. The light sensor is not limited to the detection of light. It can also be used as a detector component to form other sensors. For many non-power stop detections, it is only necessary to convert these non-electric quantities into changes in the optical signal. Light sensor is one of the most widely used and widely used sensors, and it plays an important role in automatic control and non-electrical measurement technology. Photosensors are available in a wide variety of photocells, photomultipliers, photoresistors, phototransistors, optocouplers, solar cells, infrared sensors, UV sensors, fiber optic sensors, color sensors, CCD and CMOS image sensors.
How the photosensitive receiver works
Photosensitive resistors are also called photo-sensing resistors, and their working principle is based on the internal photoelectric effect. The photosensor is equipped with a high-precision photocell. The photocell has a small plate consisting of a “needle-type two-tube”. When a reverse fixed pressure is applied to both ends of the phototube, any light impacts on it. It will incur the release of electrons. As a result, the higher the light intensity, the larger the current of the phototube. When the current passes through a resistor, the voltage across the resistor is converted to 0 by the digital-to-analog converter of the collector. -5V voltage, then collect and store the results in an appropriate manner. To be simple, the photosensor is an imitation signal that sends the light intensity to the robot host using the principle that the photoresistor is affected by the light intensity and the resistance changes.
The photoresistor is a resistor made by applying the photoelectric effect of the semiconductor to change the resistance value according to the intensity of the incident light; the incident light intensity, the resistance is reduced, the incident light is weak, and the resistance is increased. Photosensitive resistors are commonly used for light measurement, light control, and photoelectric conversion (converting changes in light into electrical changes).
Principle: It works based on the photoelectric effect of semiconductors. The photoresistor is non-polar and the tunnel is a resistive component. It can be applied with DC voltage and AC voltage. The working principle of the photoresistor: when lighting, the resistance is very small; when there is no light, the resistance is very large. The stronger the light, the smaller the resistance; the light stops and the resistance recovers.
Spectral range: from the ultraviolet region to the infrared region.
Advantages: high flexibility, small size, stable performance and low price.
Photoresist performance parameters:
The resistance when the photoresistor is not exposed to light is called a dark resistance, and the current flowing at this time is called a dark current. The resistance when exposed to light is called a bright resistance, and the current is called a bright current. The larger the dark resistance, the better, and the smaller the light resistance, the better. In practical applications, the dark resistance is about megaohms and the bright resistance is about several thousand ohms.
Sensor design plan and principle clarification
How the photosensitive receiver works
A sensor is a sensor that uses a light-sensitive element to convert an optical signal into an electrical signal. Its sensitive wavelength is near the visible wavelength, including the infrared wavelength and the ultraviolet wavelength. The light sensor is not limited to the detection of light. It can also be used as a detector component to form other sensors. For many non-power stop detections, it is only necessary to convert these non-electric quantities into changes in the optical signal. Light sensor is one of the most widely used and widely used sensors, and it plays an important role in automatic control and non-electrical measurement technology. The photoresistor is a special resistor made by applying the semiconductor photoconductivity. It is very sensitive to light, and its resistance value can change with the change of external light intensity (shading). When he is in the absence of light, he is in a high-resistance state; when there is light, his resistance value decreases rapidly. It is widely used in various control circuits (such as automatic lighting control circuits, automatic alarm circuits, etc.), household appliances (such as automatic height adjustment in TV sets, automatic exposure control in cameras, etc.) and various measuring instruments. The resistor is called a light pipe, which is simply a photoelectric device made of semiconductor materials. The photoresistor has no polarity. The tunnel is a resistor device that can be applied with either a DC voltage or an AC voltage. When there is no light, the value of the photoresistor (dark resistance) is large, and the current (dark current) in the circuit is small. When the photoresistor is exposed to light in a certain wavelength range, its resistance (bright resistance) is drastically reduced, and the current in the circuit is rapidly increased. Generally, the larger the dark resistance, the better, the smaller the bright resistance, the better the flexibility of the photo-sensitive resistor. The dark resistance value of the practice photoresistor is generally in the order of megaohms, and the value of the bright resistance is below several thousand ohms.
The light sensor converts the light intensity signal into an electrical signal through the light emitting diode and the buzzer alarm to become an automatic light intensity detection system. The light intensity is different from that of the bright sensor. When the light intensity is strong, the resistance of the photosensor is small. When the light intensity is weak, the photosensor is very large. When the light intensity is suitable, the resistance of the photo sensor is strong. Between the resistance of light and weak light. Therefore, the light signal can be converted into an electrical signal through the photosensitive sensor, and the illumination signal can be applied differently by different electrical signals generated by different illumination values to reveal different signals.