We present a novel matrix method that allows the straightforward determination of exact propagation constantsas well as the field configuration in the region that is beyond the turning point at the substrate side forarbitrarily graded-index planar waveguides.

On the basis of the transfer-matrix technique, the concept of the equivalent attenuated vector is proposed andused to analyze the characteristics of the propagating modes in planar optical waveguides with gradedrefractive-index profile; an exact analytic equation is obtained for the dispersion equation of arbitrary gradedrefractive-index planar optical waveguides.

A simple displacement measurement based on the attenuated total reflection technique is proposedand experimentally demonstrated. By analyzing the fringe shift of the reflective pattern recorded on a CCD camera, a slight displacement, which corresponds to a change in the waveguide thickness, can be determined in real time with adequate accuracy. The measurement range of this method isabout 240um, and its accuracy can reach 0.05um.

We report on a coupling method, which transfers energy of a light beam from free space into asymmetrical metal-cladding optical waveguide from the top surface without employing the prism,grating, tapered film, and other coupling components. In the experiment, a glass flat with a thicknessabout 100um, sandwiched between two gold films is used as a guiding layer. A top gold film of 46nm thick serves as a coupling layer as well as the cladding and a base gold film of 200nm servesas the substrate of the waveguide. Up to 50% of the incident light energy fed into the waveguide hasbeen demonstrated.

Based on improved attenuated-total-reflection technique,the electrically induced complex refractive index change ofelectrooptic polymer film was measured by employing the data obtainedfrom different guided wave resonance dip. Meanwhile, anaccurate measurement of electrooptic coefficient in active polymerabsorption region could also be achieved.