Versatile Optical Assembly for Ultra-Compact FOG Modulator

The development and delivery of ultra-compact lithium niobate integrated optical circuit (IOC) phase modulators for interferometric fiber optic gyroscopes (FOG) for inertial navigation and guidance systems is proposed.  The use of electrode modifications will enable a 2X reduction in Vpi for a given modulator length. The use of silicon nitride interposer end caps will reduce the long dimension of the modulator and redirect the fiber egress.  The result will be up to a 60% reduction in total fiber gyro volume when integrated with a fiber coil. The target specifications for the proposed phase modulator is a Vpi less than 4.0 V, an insertion loss less than 3.5 dB, a chip polarization extinction greater than 65 dB, and a lifetime in vacuum of more than 30 years. The proposal incorporates steps to confirm the vacuum lifetime of our current product is sustained in the new design.  The conclusion of the option period will include a preliminary reliability assessment. Six prototype modulators will be delivered to the program sponsor at the end of the effort.