Recent advances in polymer materials have significantly increase the available electrooptic coefficients. This has now
stimulated the development of new designs and configurations for high frequency optical modulators. In addition, it has
opened up the field to new applications including high speed optical Digital Signal Processing. The initial areas
investigated include linear modulators, true time delays and arbitrary waveform generation. More complex devices with
multiple elements in series are now being investigated.
We present recent developments in etchless fabrication techniques for defining low-loss waveguides in polymers. Photobleached waveguides with optical propagation loss equal to the inherent loss of the core materials have been fabricated, as well as Mach-Zehnder modulators with 4.5 volt driving voltage and fiber-to-fiber insertion loss of 8 dB. In terms of new configurations, a novel linearized directional coupler modulator that has a 10 dB enhancement in the dynamic range compared to conventional Mach-Zehnder modulators is presented. We report on the design and fabrication of polymer digital optical switches with switching voltages of 7 volts and extinction ratios greater than 20 dB. Simultaneous serrodyne frequency shifting and high-frequency phase modulation in a polymer phase modulator are demonstrated in order to simplify the setup required to implement two-color heterodyne ranging. Finally, we propose implementations of optical signal processors based on polymer optical delay lines, couplers, and electrooptic modulators, and discuss their applications to optical signal processing.