Micronor Inc. has secured U.S. patent 7,196,320 for its ZapFREE(TM) Fiber Optic Rotary Encoder
The patent recognizes Micronor's wavelength division multiplexing approach which produces a totally passive encoder utilizing no electronics within the sensor - and therefore deployable in stressful environments not suited for conventional electronic-based encoders.
The Micronor encoders meet ATEX requirements as "simple apparatus" and are certified for use in hazardous environments. An MRI-transparent encoder has been recently developed for the medical industry.
The technology was commercially introduced in 2004 as the MR3XX series ZapFREE^(TM) Fiber Optic Encoder series. Customer applications now range from aerial cable cars to electric trains; from mines to steel mills to oil rigs. The sensors are offered in 100-1024ppr resolutions as well as industry-standard shaft or hollow shaft configurations.
According to the company's press release, the MR3 XX sensors mechanically mount like any conventional rotary encoder,then connected by a simplex fiber optic link to a MR310 Remote Encoder Interface (REI) module. The REI module offers an array of standard interfaces (quadrature, serial 4-20mA and , ±10V, etc.) that ensures connectivity with all major motor drive, motion control and PLC