Optical fiber evanescent wave form quartz enhanced photoacoustic spectrum sensor and gas measurement method

The invention discloses an optical fiber evanescent wave form quartz enhanced photoacoustic spectrum sensor and a gas measurement method. The sensor is composed of a semiconductor laser source, a front single-mode optical fiber, a tapered optical fiber, a quartz tuning fork and a rear single-mode optical fiber, wherein the semiconductor laser source, the front single-mode optical fiber, the tapered optical fiber and the rear single-mode optical fiber are arranged in sequence along a light beam transmission direction; and the tapered optical fiber penetrates through a fork leg of the quartz tuning fork. Semiconductor laser is transmitted to the tapered optical fiber through the front single-mode optical fiber, and an evanescent wave field with strong energy is generated on the tapered optical fiber; gas to be detected absorbs the energy of the evanescent wave field to generate sound waves; and the quartz tuning fork receives a sound wave signal to invert gas concentration. The novel full-optical-fiber evanescent wave form quartz enhanced photoacoustic spectrum sensor is constructed aiming at sensing detection of trace gas; and compared with a traditional lens transmission system, the optical fiber evanescent wave form quartz enhanced photoacoustic spectrum sensor has the extremely low insertion loss, the stability of a sensor system is extremely improved, the structure is simple and the volume is small.