Optical properties total internal reflection

Polymethyl Methacrylate (PMMA), This material has exceptional optical clarity and resistance to outdoor exposure. It is resistant to alkalis, detergents, oils and dilute acids but is attacked by most solvents. Its peculiar property of total internal reflection is useful in advertising signs and some medical applications. 

It can be used to detect the variations in optical properties of chemical and biological films placed around the fiber [5]. The laser optical detection method based on evanescent waves is widely used in biosensors. For example, a tapered optical fiber is used to analyze the total internal reflectance fluorescence. As light is propagated down the fiber, an evanescent wave excites fluorescent tracers bound to the fiber surface. Because the evanescent wave decays exponentially with the distance from the fiber surface, the excitation radius rally extends about 100 nm into the buffer medium. A portion of the emission is captured and propagated back through the fiber to the detector. 

Applying Research The chemical structure of the material in an optical fiber gives it the properly of total internal reflection. This property, which allows these fibers to carry light, was discovered through basic and applied research. The use of this property to build networks by sending data on light pulses is the technological development of fiber optics. 

---