Forecasting avionics industry fiber optic interconnect and optoelectronic packaging challenges that lie ahead first
requires an assumption that military avionics architectures will evolve from today's centralized/unified concept based on
gigabit laser, optical-to-electrical-to-optical switching and optical backplane technology, to a future federated/distributed
or centralized/unified concept based on gigabit tunable laser, electro-optical switch and add-drop wavelength division
multiplexing (WDM) technology. The requirement to incorporate avionics optical built-in test (BIT) in military avionics
fiber optic systems is also assumed to be correct. Taking these assumptions further indicates that future avionics systems
engineering will use WDM technology combined with photonic circuit integration and advanced packaging to form the
technical basis of the next generation military avionics onboard local area network (LAN). Following this theme, fiber
optic cable plants will evolve from today's multimode interconnect solution to a single mode interconnect solution that is
highly installable, maintainable, reliable and supportable. Ultimately optical BIT for fiber optic fault detection and
isolation will be incorporated as an integral part of a total WDM-based avionics LAN solution. Cost-efficient single
mode active and passive photonic component integration and packaging integration is needed to enable reliable operation
in the harsh military avionics application environment. Rugged multimode fiber-based transmitters and receivers
(transceivers) with in-package optical BIT capability are also needed to enable fully BIT capable single-wavelength fiber
optic links on both legacy and future aerospace platforms.
With the growing maturation of vertical cavity surface emitting laser (VCSEL) technology as a source of commercial off-the-shelf components, the question of VCSEL suitability for use in avionics-qualifiable fiber-optic systems naturally follows. This paper addresses avionics suitability from two perspectives. First, measured performance and burn-in reliability results, determined from characterization of Honeywell VCSELs, are compared with application-based military and commercial avionics environmental requirements. Second, design guidelines for developing a cost-effective VCSEL optical subassembly (VCSEL/OSA) are outlined.
Packard-Hughes Interconnect has developed a detachable connector for plugging to military and commercial aerospace fiber-optic modules. The connector comprises floating spring loaded fiber-optic termini with 1-mm ceramic ferrules, all contained within a 0.136-in thick, low-profile connector plug body. The connector is mated to the package via a patented retention clip mechanism which secures the plug body to metal posts attached to the package sidewall. Optical alignment between the connector plug terminus and the package is accomplished by an alignment sleeve and mating 1-mm ceramic ferrule mounted in the package nosetube. Connector demating is performed by actuating a release button mechanism integral to the connector plug body. The fiber-optic termini in the connector plug body are easily maintained without replacing the entire connector. This makes the repair/replacement process for a broken fiber pigtail or damaged terminus endface a low cost, fast, and simple operation. The insertion loss for a simplex connector mated to a Boeing FDDI Transmitter receptacle package using 100/140 micrometers graded index optical fiber is less than 0.5 dB at 1.3 micrometers wavelength.
A standardized interface for fiber-optic sensor systems based on wavelength-division- multiplexing (WDM) has been successfully demonstrated using a novel broad-spectrum quantum-well LED and a high-resolution waveguide spectrograph. This efficient interface allows a 40-decibel system loss in 20 sensor channels. The new broadband LED and slab- waveguide spectrograph represent key enabling components for the WDM interface system. The LED produces a spectral width a factor of 3 times larger than that from conventional edge emitting LEDs in the 750-900 nm range. The compact slab-waveguide spectrograph's channel resolution (4-5 nm) and grating efficiency (>50%) compare favorably with other multimode WDM elements.
Strip-loading is a convenient and effective method to design and fabricate channel waveguides in multilayer active polymer
structures. Several micron wide strip-loaded poly(4-BCMU) waveguides are observed to be single mode at 1.06 im and
Based on the optical nonlinearity for poly(4-BCMU) measured by THG at 1.32 pm, an intensity of 650 MW/cm2 is
required to satisfy the optical phase shift material figure of merit, 4ir, for a directional coupler with 1 cm interaction
length. To estimate the optical power for directional coupler operation, we initially assume no index saturation effects,
negligible one or two photon absorption, waveguide propagation losses less than 1 dB/cm, and unity coupling efficiency.
40 W is the lowest estimated peak pulse power of operation for a device with 6 .tm2 area waveguides. Actual coupling
efficiencies of light incident on our 6 pj2 ea waveguides are between 30 % and 40 %. The propagation losses for our
sixip-Ioaded waveguides are between 4 dB/cm (i'M) and 9dB/cm (TE). The guided wave intensities are at least ten fold
lower than the input intensities. Incident peak pulse powers of at least several hundred watts will be required for 1 cm
long (lirectional coupler device operation. Initial interferometry results suggest that average power dependent thermal
phase shifts dominate peak power dependent electronic phase shifts at duty cycles approaching unity. Polymer
superlattices are considered as advanced nonlinear optical materials.