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Abstrak :
Speckle Interferometry method capable for determining both the vibration amplitude and phase shifting So that double exposure for the vibration analysis applying speckle pattern interferometry is reported. Its method is recorded on a negative film using double-exposure; two object states which are peak and valley of the object vibration are recorded. The film with double exposure is then illuminated with coherent light, and each pair produces of speckle becomes the slits of Young's experiment With using Liquid Crystal as phase modulator (switching pulse), so that switching pulse should be synchronized to the peak or valley of the object vibration. The vibration object using Ceramic Vibrator (PZT) were put on the tuning fork surface.

Abstrak :
Parallel-coupled wave-guide with symmetrical structure has interesting coupling characteristics and can be used as multiplexer/demultiplexer when certain working requirements are met. The coupling properties in the coupled wave-guide are analyzed theoretically on the basis of two mode interference effect of the propagating waves, wavelength dependence of wave-guide directional coupler is investigated in the coupling region. A rough approximation of the dependence is determined based on simplified transfer matrix multiplications followed by more detailed computer calculation using Beam Propagation method CBPMI. By varying the dimensions of wave-guide such as width, thickness, gap, interaction length, refractive index difference and wavelength we could get different coupling properties, then the results of analysis are used to select the appropriate dimensions of multiplexer/demultiplexer that works on the range of wavelength (1.3 pm - 1.6 pm). This burned channel-type directional coupler is designed on Silicon substrate to be fabricated by sputtering technology.

Abstrak :
ABSTRAK
A micro optical branching circuit [MOBC] array by the use of planar micro lens array and a cubical beam splitter was proposed in a previous study. To study further the performance of the elements of the branching array, the constructed circuit has been implemented by modulating three optical signals on different wave lengths of carrier waves transmitted by LD optical sources. The measurement on coupling efficiency gives a value of 36,4 % which is uniform for the three channels of the branching circuit. The branching circuit also shows a negligible cross-talk on the branched signals. It is summarized that the proposed MOBC implemented by modulated signals can be used in practice. The insertion loss could be reduced by appropriate positioning of each elements to achieve optimum focusing and collimating beams.

Abstrak :
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 %.

Abstrak :
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.

Abstrak :
ABSTRACT
Recently, there -is a rapidly grow in the field of optical fiber communications, particularly in the technology of fiber waveguide which is used as transmitting media or communication lines. 'Due mayor problem in optical waveguide systems is the coupling loss in connectors or couplers for the purpose of gaining maximum coupling efficiency. This research is dedicated to obtain an efficient wavegui de devi ce by studyi ng the applicability of cone-shaped fiber end-face as fiber star coupler without any complement element. Light power from one end-face of fiber was directly coupled to another cone-shaped fiber end-face. The first step of this study was the process of cone-shaping for graded-index fibers. The result was used as coupling elements in an experimental star coupler. The evaluation of the result is carried out based on the concept of radiation pattern of electromagnetic field in cone-shaped end-face of fibers- It. is concluded that the experimental star coupler is predicted to be useful with some improvement in choosing fiber-core diameter. matching the size of the coupled fibers and aligning the suitable axes of the outgoing fibers.;Recently, there -is a rapidly grow in the field of optical fiber communications, particularly in the technology of fiber waveguide which is used as transmitting media or communication lines. 'Due mayor problem in optical waveguide systems is the coupling loss in connectors or couplers for the purpose of gaining maximum coupling efficiency. This research is dedicated to obtain an efficient wavegui de devi ce by studyi ng the applicability of cone-shaped fiber end-face as fiber star coupler without any complement element. Light power from one end-face of fiber was directly coupled to another cone-shaped fiber end-face. The first step of this study was the process of cone-shaping for graded-index fibers. The result was used as coupling elements in an experimental star coupler. The evaluation of the result is carried out based on the concept of radiation pattern of electromagnetic field in cone-shaped end-face of fibers- It. is concluded that the experimental star coupler is predicted to be useful with some improvement in choosing fiber-core diameter. matching the size of the coupled fibers and aligning the suitable axes of the outgoing fibers.

Abstrak :
A fabrication and application of planar micro-lens is presented in this thesis. With the goal of alignment free of the optical component, a branching circuit have been considered. Even now, the alignment of optical components is still a problem. The advantages of the branching circuit consists of planar micro-lens is easy to connect with other optical component. Since integration of optical subsystems which allows the easy alignment and high efficiency is strongly required for future networks. But, the easier fabrication and complete alignment free of the system will be continued. In this study, the optical micro-device component which using axial focusing scheme of planar micro-lens is carried outs and the easy aligning optical system technology will be discussed.

Abstrak :
ABSTRAK
A parallel optical switching system using array structure of planar microlens was developed. The optical switching device is much simpler and low costly compared with the electronic one because it is not necessary to convert optical signals to the electronics, execute the interchange and then reconvert back to optics. The concept of parallel optical switching is constructed by using array structure of planar microlens. Aligning on array form and making match between each lens input-output pairs of planar microlens array achieved parallel coupling of optical lines.

Two sliding mirror pairs functions as optical signal switch, four 2x2 planar microlens array for focusing and collimating elements, two pairs of solenoids as magnetically force sources and a microcomputer to run control mechanism automatically between IFO ports used, are being constructed to develop a new optical networking switch. This switching system is equipped with controlling mechanism of switching direction by microcomputer. It uses parallel port of a PC and an interface that changes parallel output of PC data into the condition of voltage and current needed by moving Unit.

(Solenoid). The switching performance was applied on transmission of digital modulated signal from signal generator and serial port of personnel computer. Using one input port and three output ports, the system perform four I/O ports of 2x2 parcel optical switching with 6,98 dB and 5,75 dB insertion losses for switched state and bypass state respectively and less than -- 57 dB cross talk obtained.

Abstrak :
The advantages optical fiber in communication field are widely utilized in developing steps from electrical communication to optical communication. Optical fiber communication promise extremely high data rate over long distance transmission without needing to amplify and retransmit along the way. It is well understood that if frequency of the transmitted signals. is increased some problems such as electromagnetic interferences. crosstalk and signal distortions will appear. Those difficulties can. be solved or eliminated by using optical fiber cable. instead of copper cable. Optical fiber used to transmit and to receive information signal mutinously was usually separated in difference fibers for transmitting and receiving direction. I n this thesis a bi-directional transmission system through a single fiber with same wavelength by the use of rod lenses was constructed. A simple circuit design techniques have been used in order to make transmitter and receiver. To combine and to separate transmitter and receiver in each side to and from the fiber, two quarter-pitch GRIN rod lenses functioning as optical directional coupler was used. The result of the experiment as a model of bi-directional optical communication system shows a good performance with an appropriate reliability. The measurement results of power distribution loss. crosstalk and signal transmission quality that have been evaluated to conclude the entire result.

Abstrak :
A nonconductor optical technique, having lateral resolution of about 5 μm and vertical resolution of about 0.09 μm, for surface profile (roughness) measurement was studied. It based on a heterodyne interferometer in which two orthogonal polarized beams of slightly different frequencies were used in a modified interference microscope. The beams scanned the surface of a work piece, and the reflected beams were allowed to interfere with one another. The phase of the beat frequency of the interfering return beams is directly proportional to the surface height. The result of a surface measurement include graphical displays of surface profile, roughness (Ra), root mean square (rms) and peak to valley (P-V) value.