Device and method for improving detection sensitivity of optoacousticspectrum

Abstract

The invention discloses a device and a method for improving the detection sensitivity of an optoacousticspectrum, belonging to the technical field of optoacoustic detection. A light intensity modulator is arranged on a laser path emitted by a tunable laser, and is used for modulating the laser, the modulated laser is irradiated on a detected substance, the laser which is absorbed by the detected substance is irradiated to a quartz tuning fork to stimulate the vibration of the quartz tuning fork, the lasers emitted by a first laser and a second laser are irradiated to two fork arms of the quartz tuning fork, and then are reflected to irradiate a first position sensitive detector and a second sensitive detector which are used for detecting the laser spot positions. According to the device and the method, the lasers which are symmetrically arranged and the position sensitive detectors are used for detecting the vibration of the quartz tuning fork, and the interference signal caused by asymmetrical vibration of the quartz tuning fork due to external disturbance can be eliminated by calculating the signals of the position sensitive detectors.

Description

technical field [0001] The invention belongs to the technical field of photoelectric detection, and in particular relates to a device and a method for improving the sensitivity of photoacoustic spectrum detection. Background technique [0002] Photoacoustic spectroscopy is a spectral technique developed based on the photoacoustic effect. Photoacoustic spectroscopy measures the amount of light energy absorbed by an object. It can measure strong light scattering and opaque objects that are difficult to measure by traditional spectral methods, and the samples can be measured whether they are crystals, powders, colloids, etc. It has high sensitivity and wide application range. advantage. It has broad application prospects in physics, chemistry, chemical industry, geology, biology, medicine and other aspects. [0003] In quartz-enhanced photoacoustic spectroscopy, it is necessary to measure the amplitude of the quartz tuning fork. The vibration of the quartz tuning fork is not ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a device and method for improving the detection sensitivity of photoacoustic spectroscopy. The device of the present invention has a reasonable structural design and can solve the problem of suppression of the signal generated by the quartz tuning fork by external interference; through the method of the present invention, the signal can be collected before Initially suppress the signal caused by external interference, improve the system signal-to-noise ratio and sensitivity

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