Flexible Point to Point PWG Links: Multiple waveguides are readily imaged in flexible films with density or spacing and guide dimensions created based on customer designs. Shown is a single multimode waveguide guiding light among the many spaced on 125 micron centers in the film. These self-supporting fully connected waveguide containing films can be attached to board surfaces or embedded between boards with connection options to the board surface using mirrors, lens, fiber stub vias or “S” bending spline configurations
HDP PWG Optical interconnection demonstration circuit: These board attached waveguides were prepared for the High Density Packaging User Group consortium investigation to demonstrate the technology status and readiness for real world circuit board solutions. OIL participates with HDP and is continuing to provide demonstration PWG. OIL is currently creating exposures for next generation board level technology with functionality for an overall realistic demonstration by the consortium.
HDP/PhoxTroT consortium PWG backplane flexible circuit demonstration: Work in progress with HDP and Seagate (for the European Phoxtrot consortium) is to provide flexible multi-12-channel interconnections to 5 daughter boards measuring approximately 11 inches long with 5 flex links which terminate within MT ferrules. The flexible links with MT connectors are for daughter board interconnections. Waveguide films are imaged and undergoing processing to complete several units
PWGs directly attached to silicon chip photo diodes: Multiple units of both two and four waveguide devices were prepared and delivered to FOTA Technologies. OIL’s PWG are directly connected to on chip photodiodes coupling light through 90 deflection using metalized mirrors at the end of the guide film. Waveguides were connected to optical fiber arrays with MT style connections as shown for off board interfaces.
Intel Interposer circuit board demonstration for a TxRx board level PWG link for flip chip components: Custom work for Intel spanned several years to complete demonstration study. Custom designed multimode PWG arrays were created in self-supporting multilayer films. Laser micromachining singulated discrete strips from exposed and packaged film sheets. Additional post processing created I/O mirrors and board edge MT interfaces. Waveguides were optimized for Tx and Rx directions for optimum coupling efficiency. After QC and MT ferrule attachment for board edge connections, the metalized I/O mirror end of the waveguide films are aligned relative to board solder balls and bonded to the substrate. Note: Alternative substrates can be ceramic, glass, semiconductors, etc. VCSEL and PD arrays are aligned and flip chip bonded over the I/O mirror deflected waveguides using IR solder reflow processing.
NEC TxRx waveguide demonstration for solder ball alignment: Similar to the previous demo discussed above, waveguides were aligned by location near solder balls and are illuminated with light deflected up by the I/O mirror. Parts were created for NEC for an RF switching system.
Stratos Lightwave TxRx Optical Interconnection links for Underlying Components: Multimode PWGs optimized for Tx and Rx direction coupling were configured for Stratos Lightwave (subsequently Cinch Connectivity Solutions). The goal was to provide a compact, low profile TxRx unit for use with a B1 bomber upgrade program. The waveguides coupled 8 channels from the fiber array to the TxRx chip.The 4 input channels from the fiber array connected to through the flexible waveguide containing film to an I/O mirror that deflected the light thru a lens array to image through a transparent substrate to a PD array. Similarly, the 4 VCSEL outputs were also lens array coupled to the I/O mirror on the end of the PWG film where the waveguide propagated the light to a package edge micro custom MT style connector. This connected to a micro MT waveguide to fiber interface to a fiber ribbon for both Tx and Rx directions. The transparent substrate, where the PD’s and VCSELs were mounted, contained all drive electronics and signal processing. All alignment structures were created with laser micromachining to optimize assembly and optical coupling between all the units. Several hundred units using a pilot manufacturing station were created during the project life.
Terraconnect Central Office 48 Channel TxRx Data Link: Four waveguide containing films with 12 waveguide channels each are stacked in a 4x12 or 48 channel array. These waveguides collected light from a 4x12 VCSEL array to route light to a two stack of 2x12 or 24 outputs in MT ferrules. Conversely similar units received light and directed it to 4x12 photo diode array. The waveguides are imaged to create the curved 90 degrees in plane bend near the 4 stack 48 port surface. The output from the 4 stack is shown operating in the receiver direction in the photo. The development project was for Teraconnect with central office applications in the early 2000 time frame. Teraconnect as a company closed operations several years later.
Terraconnect Central Office 24 Channel Data Link: To reduce complexity of a 48 VCSEL and /or PD stack interconnection, as described above, a second generation 24 channel TxRx link was created for Teraconnect. The waveguide layout was simplified to be 12 straight waveguides which eliminated creation of large areas of unused waveguide material. The 90 degree bend was created by bending the film instead of imaging the curved waveguides in the film for 90 degree bend. Formation of this 90 degree bend and the ferrule to support it was also used elsewhere for daughter board to backplane interconnections as described next.
Modified Ferrule 90 Degree PWG Bends: The ability to bend out of plane 90 degrees for PWG array films enable daughter board to backplane interconnections. A number of board prototype demonstrations were created and delivered. Critical to the success for this coupling interface is the flex nature of the PWG. This design enables daughter board’s electronic pin connections to seek a bottom when inserted and allow the optical interconnection bottoming to be flexible. Demonstration units were proof of concept.