chapter  4
16 Pages

Fiber Optic Sensors

Fiber optic technology is based upon the transmission of light through fibers that can be as small as a human hair. The piping light system, although functional, was not completely successful due to non-ideal reflecting surfaces in the pipe. Fiber optics can fortunately be described in a qualitative sense. Normally light travels in a straight line, as it does in free space. Confining light within a prescribed structure will allow more direct point-to-point communications. Two very important topics that need to be addressed relative to the materials used in a fiber optic link are leaking and absorption. Absorption of light energy occurs when light interacts with impurity molecules in the glass exciting a vibrational mode in the fiber. Fiber optic links can be used to communicate both images and data. Light impinging upon a candidate area or volume can yield very useful information. Fiber optic probes are often used in assembly line sensing.