Abang Annuar EHSAN^*, Sahbudin SHAARI, and Mohd Kamil Abd. RAHMAN¹

Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia ¹Faculty of Applied Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia

(Received August 2, 2011; Accepted November 6, 2011)

Acrylic-based asymmetric and variable couplers have been developed using a single structured Y-branch design with a high-index-contrast waveguide taper and a void structure for fiber attenuation using the lateral displacement of two fibers. Device fabrication is performed by producing the device structure on an acrylic block using a computer numerical control (CNC) machine tool. The fabricated device has an excess loss of 5.85 dB, while the coupling ratios are 56.86 and 43.14% when the device is operated as a 3 dB coupler. In the asymmetric coupler mode, the coupling ratio ranges from 44.84 to 8.01% for port 1 and 55.16 to 91.99% for port 2. The excess loss of this device varies from 5.42 to 7.64 dB. In the variable coupler mode, the coupling ratio ranges from 10.09 to 32.88% for port 1 and from 89.91 to 67.12% for port 2. The excess loss of the device varies from 5.85 to 8.49 dB.

Key words: asymmetric, coupler, plastic optical fiber, POF, variable, Y-branch

^*E-mail address: aaehsan@eng.ukm.my