Mohd Syuhaimi Ab-Rahman

1×N self-made polymer optical fiber based splitter for POF-650nm-LED based application

This research focuses on fabrication of 1 by N multimode polymethyl methacrylate based step-index polymer optical fiber (PMMA SI-POF) to be proposed on application based on POF-LED combination as a main transmission media. This self-made bundled-fiber splitters have been fabricated by a perform technique. There several systems available on the market, which able to split or couple optical signals transmitted into some different channels, which are all afflicted with certain disadvantages. But all these solutions have one main disadvantage; they are all too expensive for most of the applications. So the goal of the research is to develop an economical splitter for multipurpose application over PMMA-POF. PMMA material here can be seen as one of the best solution in achieving objectives of the research due to it flexibility and cost efficiency deployment. Characterization of the splitter was reported. Red LED with 650 nm wavelength has been injected into the splitter with the aim to analyze power efficiency of the splitter. A coupling efficiency of 80% has been demonstrated. The device performance can be improved gradually through experience and practice. Main point here is the fabrication process is simple, easy and suitable to be used for household.

Characteristics study of multimode directional coupler by elliptical point contacts and CMT

The developed directional coupler using polymer optical fiber performance is studied analytically where related theories are integrated and the outcomes are analyzed. Important theories such as simplified coupled mode theory and elliptical point contacts are integrated where the parameters such as coupling length, distance between the two fibers cores and forces are varied. Using simplified coupled mode theory, coupling coefficient and coupling efficiency is obtained based on the parameters of multimode fiber coupler such as the operating wavelength, numerical apertures, coupling length and diameter of the cores. The two fibers are initially tapered at certain length at most 20 mm and attached to geometrical blocks with certain radii and the middle tapered regions of the fibers are brought closed in proximity and they are lapped to each other. Investigation of different radii of the geometrical blocks represents the effect of macro-bending when the fibers are bent when attached to the circular blocks. This concept is used to transfer the modes from first fiber to the second. Then a particular amount of load force is exerted upon one side of the blocks so that the gap is closed and leads to increment of coupling length between the two fibers. The various load force amount will give different coupling lengths and distances between the two cores, thus leading to different coupling efficiencies. Analytically the expression that represents the coupling efficiency with force is an integrated expression from simplified coupled mode theory and Hertz’s Law of elliptical point contacts. Optimized coupling efficiency obtained is as high as 70% for this study.

Realization of an Economical Self-Fabricated Polymer Optical Fiber Splitters for Small World Communication

Small world networks are promising candidates for communication networks since typical data-flow patterns in communication networks show a large amount of clustering with a small number of long-distance communications that need to be completed quickly. Polymer Optical Fiber (POF) can be and are being used in various fields of application. Two of the main fields are the automotive and the home networking. So, POF here can be seen as one of the best solutions for small world communication especially in home networking application. In this paper, optical 1x3 fused-taper-twisted polymer optical fiber (POF) splitters has been fabricated by a perform technique and proposed to be applied on small world communication application. There several systems available on the market, which can be split a coupled signal to be transmitted into some different channels, which are all afflicted with certain disadvantages. But all these solutions have one main disadvantage; they are all too expensive for most of the applications mentioned above. So the goal of this study is to develop an economical splitter for small world communication over POFs. Characterization of the splitter was reported. Red LED with a 650 nm wavelength has been injected into the splitter for the purpose of characterization testing to analyze the level of power efficiency of the splitter. Final analysis shows that efficiency of splitter output able to reach up to 30%. The device performance can be improved gradually through experience and practice. Main point here is, the fabrication process is simple, easy and suitable to be used for household.

Karman Vortex Creation Using Cylinder for Flutter Energy Harvester Device

This study presents the creation of a Karman vortex for a fluttering electromagnetic energy harvester device using a cylinder. The effects of two parameters, which are the diameter and the position of the cylinder, were investigated on the Karman vortex profile and the amplitude of the fluttering belt, respectively. A simulation was conducted to determine the effect of the creation of the Karman vortex, and an experiment was performed to identify influence of the position of the cylinder on the fluttering belt amplitude. The results demonstrated that vortex-induced vibration occurred at the frequency of the first natural mode for the belt at 3 cm and 10 cm for the diameter and position of the cylinder, respectively. Under such configuration, an electromagnetic energy harvester was attached and vibrated via the fluttering belt inside the turbulent boundary layers. This vibration provides a measured output voltage and can be used in wireless sensors.