In order to perform these tests, the basic fiber optic instruments are the FO power meter, test source, OTDR, optical spectrum analyzer and an inspection microscope. These and some other specialized instruments are described below. ) are covered in these procedures. These fibers are most commonly made of glass and are very thin, typically less than a tenth of the width of a human hair. With the widespread use of optical fibers in high-speed communication, high-performance, reliable, and stable optical fibers are crucial for networks, making fiber optic detection a very important task.