Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
ABSTRACT
An experimental micro optical branching circuit (HCBC) array has been constructed by the use of planar microlens. Three substrates of 3x1 nicrolens array have been used as collimating and focusing elements in the proposed circuit. A cube beam splitter was utilized as branching element with a branching ratio 1:1, for reflecting and transmitting beams, respectively. Evaluation has been carried out by measuring the coupling efficiency of the proposed HOBC. The branching characteristic for digital modulated signal has also been carried out. Theoretical calculations was taken into account for evaluating the performance of the branching circuit.

Abstrak :
ABSTRACT
High Voltage measurement based on the electro-optic effect of LiTaOa crystal plate has been developed. This crystal was placed between two parallel plates which more like capacitor arrangement.

On the first step, this system was capable only to measure the do voltage from 0 to 1 kV, and the ac voltage from 0 to 0.3 kV. But, by enlarging the spaces in between one side at crystal to one of the plate surface, d, the range of measurement was increased up to 4.8 kV, with d =7 mm.

Abstrak :
ABSTRACT
In optical communication system, optical star coupler devices are important for distributing optical signal from one incoming fiber into several outgoing fibers. In this research, an investigation on the design of optical fiber star coupler has been carried out by the use of simple way. Utilizing the cone-shaped end face of several fibers as receivers, optical star coupler has been constructed without using any optical element .An experiment to examine the efficiency of coupling light power from an incoming fiber to seven outgoing fibers has been excetited. The measurement shows that each sample of set outgoing fibers receives an equal amount of light power, which means that the individual coupling efficiency of respective outgoing fibers is equal. Therefore, it is concluded that the proposed star coupler is applicable to be utilized for distributing a light signal to several output terminals.

Abstrak :
ABSTRAK
Recently, the distributed index microlenses have been introduced as the novel elements for coupling device in microoptic circuitry. A potential advantage of such microlenses as microoptic components is the possibility of gaining a Large nemerical aperture so that incoming Light can be effectively guided, for example in optical coupler, branching circuits, wavelength multiplexer / demultiplexer and so on. The coupling property of microlenses is the basic application of microlenses in optical communication system. this study, a coupling circuit using paired microlenses with distributed index of refraction has been developed. The variation of coupling efficiency due to Lateral offset, angular misalignment and end separation of two coupled microlenses has been experimentally measured. Evaluation on the result was carried out by computer simulation based on phase space representation of ray tracing. It is concluded that the coupling property of distributed index microlenses is affected by the index profile of respective microlenses as predicted by phase space analysis. Furthermore the phase space representation has also been utilized to analyze the coupling efficiency of microoptical coupler.