Pressure sensors are a type of device used to measure pressure. They can be divided into the following types according to their working principles and application fields:

1. Strain gauge pressure sensor: This sensor uses the resistance change of the strain gauge to measure pressure. When pressure is applied to a strain gauge, its shape changes slightly, causing a change in resistance. This kind of sensor is suitable for industrial automation, automotive fields, etc.

2. Capacitive pressure sensor: Capacitive pressure sensor uses changes in capacitance to measure pressure. When pressure is applied to the sensor, the distance or medium between the capacitors changes, causing a change in the capacitance value. It is commonly used for liquid level measurement and liquid pressure measurement.

3. Piezoelectric pressure sensor: This sensor uses the piezoelectric effect, which generates electric charges under pressure, and converts pressure into electrical signals. Piezoelectric pressure sensors perform well in harsh environments such as high temperature and high pressure, and are commonly used in aerospace, petrochemical and other fields.

4. Gas conduction pressure sensor: Gas conduction pressure sensor infers the pressure of the gas by measuring the thermal conductivity of the gas. It is suitable for gas flow measurement and gas system monitoring.

5. Resonance pressure sensor: Resonance pressure sensor uses the natural frequency and resonance characteristics of the material to measure pressure. When external pressure acts on the sensor, its resonant frequency changes, thereby achieving pressure measurement. It is widely used in high-precision measurements, such as laboratory instruments, etc.

6. Fiber optic pressure sensor: This sensor uses changes in optical fibers to measure pressure. When pressure is applied to an optical fiber, its refractive index changes, changing the way light travels. It is suitable for applications requiring long-distance transmission and immunity to electromagnetic interference.

These different types of pressure sensors play an important role in different application fields, helping us monitor and measure pressure in real time to ensure the safety and stability of various industrial processes.