QinetiQ has developed an optical hybrid technology that uses a hollow waveguide (HWG) to improve performance while reducing expenditure. The HWG has the potential to cut more than 50% off the cost of complete optical circuits, says Qinetiq.

QinetiQ has developed an optical hybrid technology that uses a hollow waveguide (HWG) to improve performance while reducing expenditure. The HWG has the potential to cut more than 50% off the cost of complete optical circuits, says Qinetiq.


The HWG is etched or cut from a flat substrate to provide a guide channel in the material. Coating the guide walls to alter their optical properties can enhance the performance. A lid is attached to provide the fourth guide wall. HWGs complement traditional "rib" or "ridge" structure to maintain all the usual performance criteria. It also allows greatly simplified assembly of components or modules. For example, the insertion of a component into a guide now involves only two interfaces - one is the guide to component interface and the second the component to guide interface (in both cases the guide is air). This compares with the four interfaces involved in the conventional rib waveguide (guide to air to component to air to guide).


The unique technology enables light to be guided directly from device to device across a large area. This overcomes the problems of beam divergence and alignment accuracy.


Another major benefit of the HWG is that monolithic functions can be integrated during the same fabrication process that is used to create the hollow waveguides. These might include MEMS devices, multi-mode interference (MMI) devices and free space component functions.


QinetiQ offers a design service for HWG integration into specific applications. QinetiQ can also provide access to substrate fabrication and designs may be transferred directly into customer facilities, or passed to preferred partners for high volume manufacture.