Properties of Large Core Polymer Optical Bend Waveguides

We report about properties of large core plastic planar optical bend waveguides. The dimensions of the waveguides were to be compatible with the commonly used plastic optical fiber with diameter 750 mu m and the bend radii of the waveguides varied from 30 to 1 mm. The waveguides were made by engraving of a U-groove by using CNC machining into poly(methyl methacrylate) substrate; the waveguide core layers were made of Norland Optical Adhesive UV photopolymer. We experimentally confirmed that fabricated bends may have the total bend losses A for radii 30 mm 4.1 dB/cm at 850 nm, 4.8 dB/cm at 650 nm and 5.63 dB/cm at 532 nm. These bend waveguides are viable for short reach visible and infrared optical communication with easy and low cost installations.