Patent ID: 8731342

Claim:
A fiber-optic detection system for liquid-immersion detection, comprising: an optical time domain reflectometer; a backbone optical fiber coupled to the optical time domain reflectometer; an optical splitter disposed on the backbone optical fiber to split a detection light; a branch optical fiber coupled to the optical splitter and receiving the detection light; and a fiber-optic sensor for liquid-immersion detection, coupled to the branch optical fiber, the fiber-optic sensor for liquid-immersion detection comprising: an optical fiber having one end coupled to the branch optical fiber and the other end comprising an angled physical contact surface; and an interface material layer contacting the angled physical contact surface of the optical fiber, wherein the interface material layer has a rough surface to produce a diffusion reflection when in a dry state and a smooth surface to produce a specular reflection when absorbed a liquid in a wet state, wherein the detection light output from the optical splitter generates an optical power difference through a difference between the diffusion reflection and the specular reflection when being reflected back to the optical time domain reflectometer to identify whether or not the interface material layer is in the dry state or the wet state.