Precision measurements for propagation properties of high-definition polymer waveguides by imaging of scattered light

We present a reliable, nondestructive, and real-time technique for characterization of propagation properties of planar optical waveguides based on accurately imaging the scattered light from the optical waveguide using a sensitive charge-coupled device (CCD) camera with built-in integration functionality. This technique can be used for real-time investigation of the propagation properties (loss, mode profile, bending properties, etc.) as well as the fabrication quality of planar optical waveguides. With this technique, we evaluate high-definition polymer optical waveguides on printed circuit board (PCB) substrates with a very low loss of 0.065 dB/cm at a wavelength of 850 nm, and measurement accuracy is less than 0.01 dB/cm. We expect this technique with the given CCD camera to be suitable for reliably measuring loss coefficients well below 0.1 dB/cm.