Polymer waveguides provide cost effective interconnect solutions for high-volume applications required by the rapid growth in VCSEL array sizes and product demand. Multimode polymer waveguides 34-channels wide have been stacked in arrays 12-layers high with center-to-center waveguide spacing of 125 +/- 2 microns between layers and 90 +/- 2 microns within a layer. No measurable crosstalk between channels has been observed even when separation between multimode waveguides was reduced to a 4-micron gap. Flexible polymers provide an out-of-plane bend radius of less than 5 mm that simplifies VCSEL packaging requirements and volume. Transitioning the waveguide pitch within and between the polymer layers from 125 to 250 microns enables interface of high-density VCSEL arrays to standard fiber ribbons. Passive fiber pigtailing to 62.5/125 fibers was achieved with < 0.5 dB loss. Pigtailing can be avoided entirely by direct connectorization of the polymer waveguide arrays with industry standard MT connectors. Optical CrossLink's Guidelink polymer waveguide devices are made form sheets several hundred feet long. Waveguide's are formed using contact photolithography that requires no costly spin- coating, wet chemistry, embossing, modeling or etching techniques required by other planar waveguide fabrication processes. All required processes are suitable for automation with high-yield while at the same time drastically reducing the infrastructure required to produce devices. Currently, the equivalent of 100 six-inch wafers of planar waveguides can be produced in less than 2 days without automated machinery.
A down-conversion photonic link implemented with a pair of parallel Mach-Zehnder modulators has been demonstrated. The block down-converter has a fixed local oscillator at 22 GHz and has demonstrated conversion of the 26 - 40 GHz millimeter-wave band down to the 4 - 18 GHz microwave intermediate frequency band. A conversion efficiency improvement over down-conversion links with serial modulator topologies with comparable components is predicted.
A polynomial evaluator utilizing a pipelined architecture has been constructed and tested. Some notable features of this processor are its unusual design its speed in polynomial evaluation and its ability to rapidly compute the zeros of polynomials. This optical computer utilizes sequential processing by seven electrooptic gratings which perform alternate addition and multiplication functions in the pipeline. Its performance as a square-root processor and as a cubic polynomial evaluator are stressed. Characterization measurements upon the individual gratings and upon the processor as a system are presented. 1.