Fibercore, a UK developer and manufacture of specialty optical fibers, has announced the release of two, enhanced-performance PM fibers developed specifically for next generation Fiber Optic Gyroscopes (FOGs).
The two strongest trends in FOG development today are enhanced precision and reduced form-factor – often in the same package. With bias stability figures of fractions of a degree per hour, these new generations of FOG now rival the very best ring-laser and conventional, iron gyros in terms of precision whilst also delivering the fundamental ruggedness and longevity that no other gyro technology can match. These enhancements are opening-up an increasing range of high-precision / high-reliability, applications from compact IMUs for land and air navigation through to ultra-high precision gyrocompasses for ships and submarines. We are also encountering a significant increase in demand for fibers for sub-miniature, highgrade tactical FOGs with coil diameters comfortably below one-inch (25 mm).
One of the most straightforward ways of increasing the performance of a FOG is to increase the length of fiber in the sensor coil – the longer optical path-length generating a greater phase-shift for any given rotation. Increasing the length of fiber in the sensor coil creates two significant challenges – increased coiling stress and microbending and increased coil volume / form-factor. Fibercore’s two new product variants of HB1500G-SB (155um and 135um) have been re-designed from the glass outwards, specifically to address these challenges.
The new product variants of HB1500G-SB (155um and 135um) have been independently evaluated as having best-in-class performance of any FOG fiber on the market today. The fibers were developed through a dedicated development program to improve the coating packages and glass design through the use of advanced simulation tools and empirical testing at the FOG coil level.
Early adopters have achieved exceptional PER results for the new gyro fibers, far beyond previous levels. One of our North American customers has even gone so far to say, “PER is superior compared to all the other reduced buffer fibers that we have been evaluating”.