Abstract: The present invention belongs to the technical field of trace gas detection, and relates to a multi-cavity semi-open resonant photoacoustic cell and a multi-gas simultaneous measurement system. The photoacoustic cell includes multiple resonant cavities. Each resonant cavity has a unique length and a unique resonant frequency, so each resonant cavity corresponds to one to-be-measured gas. A sensitive diaphragm of an acoustic sensor is fixed on one end face of the photoacoustic cell. Photoacoustic signals of different frequencies generated in the resonant cavities act on the sensitive diaphragm of the acoustic sensor, causing the sensitive diaphragm of the acoustic sensor to vibrate periodically. Concentration information of multiple to-be-measured gases can be obtained by analyzing the vibration of the sensitive diaphragm of the acoustic sensor.

Abstract: The present invention belongs to the field of trace gas detection technology and provides a multi-cavity superimposed non-resonant photoacoustic cell and gas detection system. The multi-cavity superimposed non-resonant photoacoustic cell includes a cylindrical metal shell, a plurality of non-resonant photoacoustic cavities, a sensitive diaphragm of the fiber-optic Fabry-Perot acoustic sensor, an optical glass window, an air inlet and an air outlet. The circular sensitive diaphragm of the fiber-optic Fabry-Perot acoustic sensor is fixed on one side of the cylindrical metal shell, and the other side of the cylindrical metal shell is sealed by an optical glass window. The gas to be measured enters through the inlet, diffuses into a plurality of non-resonant photoacoustic cavities, and exits through the outlet on the other side.

Abstract: The present invention belongs to the technical field of trace gas detection, and relates to a multi-cavity semi-open resonant photoacoustic cell and a multi-gas simultaneous measurement system. The photoacoustic cell includes multiple resonant cavities. Each resonant cavity has a unique length and a unique resonant frequency, so each resonant cavity corresponds to one to-be-measured gas. A sensitive diaphragm of an acoustic sensor is fixed on one end face of the photoacoustic cell. Photoacoustic signals of different frequencies generated in the resonant cavities act on the sensitive diaphragm of the acoustic sensor, causing the sensitive diaphragm of the acoustic sensor to vibrate periodically. Concentration information of multiple to-be-measured gases can be obtained by analyzing the vibration of the sensitive diaphragm of the acoustic sensor.

Abstract: The present invention provides the Fabry-Perot (F-P) sensor compromising housing, measuring probe, longitudinal sling block, and displacement converting device. The optic fiber passes through upside sealing ring and extends into upside through hole with the optic fiber end surface disposed at the bottom; the upside of longitudinal sliding block is disposed with reflecting surface, thus a Fabry-Perot cavity is formed between part of the fiber end surface at the bottom of the fiber and the reflecting surface on the upside of longitudinal sliding block. The displacement converting device will convert the lateral slides of the measuring probe into the slides of the longitudinal sliding block, which thus changes the distance from the reflecting surface to the fiber end surface and changes the Fabry-Perot cavity length. Further, the sliding distance of the measuring probe can be calculated after the variation of the Fabry-Perot cavity length measured in according with the Fabry-Perot principle.

Abstract: The present invention provides a Fabry-Perot sensor for measuring inclination. Wherein the present inclinometer is fixed on a static detected object in application use, the mass block is flexibly connected to the top plate, thus the line between the center of gravity of the mass block and the connecting point on the top plate is perpendicular to the horizontal plane; a Fabry-Perot cavity is formed between the reflecting surface disposed at one end of the mass block and the end of the optic fiber. The detected object will be in a static state after tilting, the line between the center of gravity of the mass block and its connecting point on the top plate is still perpendicular to the level plane and the F-P cavity length will have a variation. Then the change of cavity length can be measured in accordance with the Fabry-Perot principle, thereby the tilting angle of the mass block is able to be further measured. Then the tilting angle is also the inclination of the detected object.