Gas detecting device based on multiple reflection of integrating sphere

Abstract

The invention discloses a gas detecting device based on multiple reflection of an integrating sphere. The device comprises an integrating sphere, an optical fiber, a photodetector and a transparent air chamber. The integrating sphere comprises a first hemisphere and a second hemisphere, a first air outlet, a light inlet and a light exit are formed in the first hemisphere, a first lens is arrangedat the light inlet, a second lens is arranged at the light exit, a first air inlet is formed in the second hemisphere, one end of the optical fiber is connected with the first lens, and the other endis connected with a light source; the photodetector is disposed outside the integrating sphere, and the light inlet end is connected to the light exit on the integrating sphere; the transparent air chamber is disposed in the integrating sphere, the transparent air chamber is provided with a second air inlet and a second air outlet which is communicated to the first air inlet on the integrating sphere; the second air outlet is communicated to the first air outlet on the integrating sphere. According to the device, the light is absorbed by the gas through the gas chamber after being reflected multiple times inside the integrating sphere. Since the gas is stored in the gas chamber independently of the integrating sphere, the integrating sphere can be prevented from being corroded by the gas.

Description

technical field [0001] The invention belongs to the technical field of gas analysis, and in particular relates to a gas detection device based on multiple reflections of an integrating sphere. Background technique [0002] When a continuous wavelength of light is hit on a certain gas, the gas will absorb some specific wavelengths of light, thereby reducing the intensity of the beam, and expanding the beam to the spectrum, forming the absorption spectrum of the substance. Based on the Lambert-Beer law, the concentration of the gas can be directly retrieved by using the degree of attenuation of the light intensity after passing through the gas. The longer the optical path of the light source through the measured gas, the more accurate the measured gas concentration data. Traditional multiple-reflection long-path gas absorption cells mainly include Heriot cell and White cell. The Herriott cell is a coaxial resonant cavity structure composed of two identical spherical mirrors....

AI Technical Summary

Problems solved by technology

These two gas absorption cells have been widely used, but both of them have the problems of high surface processing accuracy and relatively expensive cost. If it is polluted, it needs to be replaced as a whole, resulting in an increase in application costs

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