Organic vapour detection system - with liquid crystal coated optical waveguide whose transmission varies when vapour contacts guide

摘要

The detection device for organic vapours comprises an elongated waveguide, a light source (1) which transmits light along the length of the waveguide, and a system (8-10) for measuring the light at the other end of the guide (7). The surface of the guide is coated with a liquid crystal material which is sensitive to the organic vapour so that the light transmission capacity of the waveguide varies in a measurable fashion when the guide contacts the vapour. The luminous source is typically a tungsten filament lamp.