公开(公告)号：US06680479B1

公开(公告)日：2004-01-20

申请号：US09601325

申请日：2000-09-25

Applicant: Stuart Charles Murray

Inventor： Stuart Charles Murray

IPC: G01N2131

CPC classification number: G01N21/3554 ,  G01J3/427

Abstract: A water detecting apparatus includes a source of infra-red radiation which is reflected off an inner surface of a pipe wall onto a mirror directing the infra-red signal along a path to an infra-red detector connected by an electrical signal path to an electronic control. The path is interrupted by a rotating chopper having windows occupied by two optical filters. The first optical filter only passes an infra-red signal of wavelength 1900 nm which is absorbed by water, while the second optical filter only passes an infra-red signal of wavelength 2200 nm, another wavelength absorbed by water, but not to the same extent as the 1900 nm wavelength. The 2200 nm wavelength serves as a reference signal. When the strength of the infra-red signal path by the first optical filter decreases in relation to the strength of the infra-red reference signal path by the second optical filter, this is due to water on the surface absorbing the 1900 nm wavelength more than the 2200 nm wavelength, and the electronic control causes an indicator to indicate the presence of the water.

Abstract translation: 水检测装置包括红外辐射源，其从管壁的内表面反射到反射镜上，该反射镜将红外信号沿着通过电信号路径连接到电子信号路径的红外线检测器的路径 控制。 该路径被具有由两个光学滤波器占据的窗口的旋转斩波器中断。 第一光学滤波器仅通过由水吸收的波长为1900nm的红外信号，而第二滤光器仅通过波长为2200nm的红外信号，另一波长被水吸收，但不是相同程度 作为1900nm波长。 2200nm波长用作参考信号。 当第一滤光器的红外信号路径的强度相对于第二滤光器的红外参考信号路径的强度降低时，这是由于吸收1900nm波长的表面上的水超过 2200nm波长，并且电子控制使得指示符指示水的存在。