Methane Gas Detection Micro Fp Comb Filter Study

The mineral product gas sensor's safe examination has the very vital practical significance. The aim of the article is to research and design the miniature F-P comb filter which is applied to examine the methane gas. It realizes the high sensitive online telemetry in order to achieve the goal of monitoring the movement.The optical fiber gas sensors are widely used because it has a series of unique technical superiority. This article has analyzed the existing optical fiber gas sensors'technology principles and methods on the basis of optical fiber gas sensors'developing process and the present condition. It pointed out that their merit and the applicable limitation, and it elaborated F-P comb filters'principles, and the production process. At the same time, it proposed to design one kind of F-P comb filter which is combined with optical fiber collimator and take plating K9 material as the substrate based on the transmitted light nature of K9 glass. This method has high selectivity, good precision, and it may obtain the high signal-to-noise ratio.It is based on analyzing methane gas's near-infrared absorption line to use the central wave length 1650mm,30nm wide band's SLED light sources and the optical fiber, as well as the sensing air chamber to construct the light concentration gas absorption examination system. In the article, it has made the design of the light path and the air chamber, and the questions of F-P comb filters'design and manufacture have been analyzed and discussed detailedly. Its key point is to disscus the systemic loss and to analize the spectrum and error. The monitoring sensitivity of the system has been increased. It has obtained a good experimental result through comparing the theoretical calculation and the data which obtained from the experiment. The result has confirmed the miniature F-P comb filters'applicable feasibility in monitoring of gas, and it has provided the advantageous help to the experiments of methane gas.