Where are infrared sensors used?
1. Flame detector
Flame sensors utilize the characteristic that infrared light is highly sensitive to flames. They use a specially designed infrared receiver to detect flames, and then convert the brightness of the flames into high and low level signals, which are input to the central processing unit. The central processing unit performs corresponding program processing based on the changes in the signal.
The flame sensor can detect infrared light with wavelengths in the range of 700 nanometers to 1000 nanometers, with a detection angle of 60°. The sensitivity is maximized when the infrared light wavelength is around 880 nanometers.
The far-infrared flame detector converts changes in the intensity of external infrared light into changes in current, which are then reflected as numerical values within the range of 0 to 255 by an A/D converter. The stronger the external infrared light, the smaller the value; the weaker the infrared light, the larger the value.
Infrared range sensors utilize the principle that the intensity of infrared signal reflection varies depending on the distance to an obstacle to detect its distance. An infrared range sensor has a pair of infrared signal emitting and receiving diodes. The emitting diode emits an infrared signal of a specific frequency, and the receiving diode receives this frequency signal. When the infrared signal encounters an obstacle, it is reflected back and received by the receiving diode. After processing, the signal is returned to the central processing unit (CPU) via a digital sensor interface. The CPU can then use the returned infrared signal to identify changes in the surrounding environment.
2. Infrared thermometer
An infrared thermometer mainly consists of an optical system, a modulator, an infrared sensor amplifier, and an indicator. An infrared sensor is a device that receives radiation from a target and converts it into an electrical signal. [1]
3. Infrared imaging
In many situations, it's not enough to know the average surface temperature of an object; one also needs to understand its temperature distribution for analysis, structural research, and detection of internal defects. Infrared imaging can visually display this temperature distribution in the form of an image.
Precautions for Infrared Sensor Applications
Infrared sensors are crucial components in infrared detection systems, but they are delicate and can be damaged if not handled carefully. Therefore, the following points should be noted when using infrared sensors:
1. It is essential to first understand the performance specifications and application range of infrared sensors, and master their usage conditions.
2. It is essential to pay attention to the operating temperature of the sensor. Generally, an infrared sensor that can operate at room temperature should be selected for ease of maintenance.
3. Adjust the operating point of the infrared sensor appropriately. Generally, a sensor has an optimal operating point. The signal-to-noise ratio of the infrared sensor is maximized only when operating at the optimal point.
4. Select an appropriate preamplifier to work with the infrared sensor to obtain the best detection results.
5. The modulation frequency is matched with the frequency response of the infrared sensor.
6. Do not touch or wipe the optical parts of the sensor with your hands to prevent damage and contamination.
7. When storing sensors, pay attention to moisture prevention, vibration prevention, and corrosion prevention.
