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"In this research work an experiment on the application of fiber sensor for measuring an acoustic vibration has been carried out. A light beam from He-Ne laser source was into two arms of Mach tender Interferometer. Each arm of the interferometer was a piece of optical fiber with a length of 2 m.The beam transmitting through the sensing arm was modulated in phase by an acoustic vibration produced by a signal generator. The output of this fiber was interfered with the light radiated from the undisturbed fiber, the reference arm of the interferometer. A fringe counter measured a fringe shift due to the vibration of the acoustic signal. The measurement shows a good response in terms of the number of fringes with respects to the acoustic vibration in a frequency range of 10 Hz up to 40 Hz. It is concluded that the system is applicable to measure an acoustic vibration with an accuracy of 7 %."

"ABSTRACT As transmission medium in optical communication system, optical fiber is also characterized by elastic properties beside of transmission properties of optical fiber. The Young Modulus of Elasticity of optical fiber could be measured by considering a bare optical fiber as cantilever which resonant with an acoustical vibration. To detect the cantilever vibration, a HeNe laser light is launched into the cantilever of optical fiber through its free end and the output laser light is detected by a PMT and observed by the channel 2 of an oscilloscope. Channel 1 of the oscilloscope observes the signal of the acoustical vibration. Regulating both the frequency and amplitude of the vibration or the position of the pinhole of the PMT, the resonance frequency of the cantilever could be detected accurately. Using the data of the resonance frequencies of various length of the cantilever has been calculated. "

"Development of optical fiber communication system is mainly due to the progressive influence of optical source. Laser diode as optical source in optical transmission system is of great attention because laser diode produces coherent monochromatic-light. Furthermore, laser diode has a high quantum efficiency, can be modulated at a very high speed, has small size and compact. The application of such optical source is also wide, ranging from optical signal communication to radar optics. Therefore, laser diode is considered to be a key component in optoelectronic system. In this study, an experimental model of analog optical transmission system with laser diode as optical source at wavelength of 0.79 pm has been designed and constructed. The design and construction include optical and electronic circuits. Design description at the wavelength used in this study is briefly described. The characteristics of the system was evaluated by measuring the frequency responds of photo detector, the transmission bandwidth and the loss of the system. The result shows that the frequency responds of the photo detector limits the transmission bandwidth of the whole system. On the other hand, by the use of the selfoc lens for coupling laser diode to fiber line, a coupling efficiency as high Es 55 % has been achieved. Based on the evaluation on the result obtained for the experimental model the practical applicability of the system is pointed out."

"Optical-fiber-based telecommunication networks have become a major information-transmission-system, with high capacity links encircling the globe in both terrestrial and under sea installations. This edition presents the fundamental principles for understanding and applying optical fiber technology to sophisticated telecommunication systems."

"Optical-fiber-based telecommunication networks have become a major information-transmission-system, with high capacity links encircling the globe in both terrestrial and under sea installations. This edition presents the fundamental principles for understanding and applying optical fiber technology to sophisticated telecommunication systems."