公开(公告)号：US20030147080A1

公开(公告)日：2003-08-07

申请号：US10359526

申请日：2003-02-05

Applicant: Detector Electronics Corporation

Inventor： Randall G. Sarkis ,  John M. Jarvis

IPC: G01N021/00

CPC classification number: G01N21/359 ,  G01N21/3504

Abstract: An apparatus and method for open-path gas detection. The apparatus includes a radiation source and first and second radiation detectors sensitive to radiation in first and second spectral bands. The long cut-off wavelength of the second spectral band is longer than the long cut-off wavelength of the first spectral band, and the short cut-off wavelength of the second spectral band is shorter than the short cut-off wavelength of the short spectral band, such that the second spectral band is wider than and completely overlaps the first spectral band. Radiation from the radiation source passes through the area to be checked for gas, and is partially absorbed if gas is present. The path between the radiation source and the first and second radiation detectors need not be enclosed, and may exceed 100 meters in length. A processor compares intensity signals from the radiation detectors with a threshold value, and generates an output signal indicating a presence of gas based on the comparison. The method includes the steps of passing radiation through an area, and sensing radiation that has passed through the area within first and second spectral bands, wherein the long cut-off wavelength of the second spectral band is longer than the long cut-off wavelength of the first spectral band, and the short cut-off wavelength of the second spectral band is shorter than the short cut-off wavelength of the short spectral band. The intensities in the spectral bands are compared with a threshold value, and the presence of gas is indicated based on the comparison.

Abstract translation: 用于开放式气体检测的装置和方法。 该装置包括辐射源和对第一和第二光谱带中的辐射敏感的第一和第二辐射检测器。 第二光谱带的长截止波长比第一光谱带的长截止波长长，第二光谱带的短截止波长短于短截止波长 使得第二光谱带宽于第一光谱带并且与第一光谱带完全重叠。 来自辐射源的辐射通过要检查的气体的区域，并且如果存在气体则被部分吸收。 辐射源与第一和第二辐射探测器之间的路径不需要被封闭，并且长度可能超过100米。 处理器将来自辐射检测器的强度信号与阈值进行比较，并且基于该比较产生指示气体存在的输出信号。 该方法包括以下步骤：使辐射通过一个区域，并感测已经穿过第一和第二光谱带内的区域的辐射，其中第二光谱带的长截止波长比长截止波长长 第一光谱带和第二光谱带的短截止波长比短光谱带的短截止波长短。 将光谱带中的强度与阈值进行比较，并且基于比较来指示气体的存在。