Arrayed Fiberoptics, developing a standard platform for integrated fibre optic components, has announced an epoxy-free fibre array, designed to be used as a subcomponent for planar lightwave circuits (PLCs), such as arrayed waveguide gratings (AWGs).

Currently, Arrayed Fiberoptics said, the industrial practice for PLC waveguide-to-fibre coupling is simple butt-coupling using epoxy. In this approach, the PLC edges are polished, aligned, and epoxy bonded to a fibre array device. The fibre array device is typically made by machining V-grooves into the surface of a glass or silicon plate, and placing the fibres in these grooves. Epoxy bonding provides quick and simple alignment, low cost, and robust packaging.

However, this approach leaves epoxy in the optical path, where it causes limitations in power, performance and reliability due to epoxy degradation. These problems are most acute for AWGs, because they are typically used in long-haul DWDM applications, which require very high power. These limitations have inspired various attempts to eliminate epoxy from the optical path, typically through the use of additional hardware such as microlenses or external mounting plates. However, due to the complexity and cost of these approaches, they have not been widely adopted.

Arrayed Fiberoptics' epoxy-free fibre arrays (EFFAs) incorporate a patent-pending, integrated epoxy-blocking structure. The company maintains that the EFFAs preserve the simplicity, low cost, and robustness of typical fibre butt-coupling, while keeping the optical path epoxy-free. As a result, PLC manufacturers can use their existing packaging designs with very little modification.

The EFFAs can be configured in linear arrays up to 1x64 channels and 2-D arrays, with array pitch as small as 127 um. Even in large arrays, EFFAs provide very precise positioning of fibres, to +/- 0.3 um in both the horizontal and vertical dimensions. This is much higher precision than is available from the V-groove technology traditionally used for similar applications. Arrayed Fiberoptics' EFFAs are claimed to not only enable higher power and reliability in devices, but also enable improved device performance due to better alignment precision. Further, unlike V-grooves, the EFFAs enable not only linear arrays, but also 2-D arrays.

Typical applications for Arrayed Fiberoptics' EFFAs include coupling to PLCs or array devices, such as AWGs, beam splitters, OADMs, optical cross-connect switches, microlens arrays, etc. Arrayed Fiberoptics said it will team with component vendors to integrate the EFFAs into their existing devices for improved characteristics, or alternatively they can be used to create new component designs.

Evaluation samples of Arrayed Fiberoptics' EFFAs are available immediately with 250um pitch, and EFFAs with pitch as small as 127 um are currently in development.