Micronor’s magnetic resonance imaging (MRI)-compatible fiber-optic absolute rotary encoder system features 13-bit (8192 count) resolution and 12-bit multiturn tracking. The all-optical, nonmetallic MR338 passive sensor provides precision absolute angular measurement from 0° to 360°. A duplex multimode fiber-optic link connects the passive MR338 sensor to the active MR330 controller module installed outside the MRI area. This system is designed for use in functional-MRI research, MRI training phantoms, EMC test facilities, and other challenging electromagnetic environments where EMF and RF transparency is required. The MR330-1 SSI controller's embedded processor and firmware offers performance plus an extended set of built-in functions and interfaces not available with resolvers or conventional electronics-based encoders.