FSI M4-R Interrogator

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The M4-R optical sensing instrument is an economic commercial grade interrogator, featuring 4 monitoring channels. Enclosed in a field deployable enclosure, the instrument can be operated in full spectrum and in sensor peak detection modes. The M4-R is optimized for both static and dynamic measurements of up to 30 Fiber Bragg Gratings (FBG) based sensors on each of its 4 channels. Additionally, the M4-R includes an internal Raspberry PI processor for added functionality and controls.

Our family of rugged MX interrogators is used extensively in civil engineering, marine, railways, roads, energy, geotechnical, industrial, security, medical, and many other commercial applications. This economy model is specifically useful for security, civil engineering, energy, process control, material qualification labs, and R&D programs. The industrial grade design scales well for volume production.


Repeatability, accuracy, and dynamic range: The M4-R Interrogator provides measurements across its wavelength scanning range of 40nm. Using US patented laser calibration technology, the instrument features +/- 2pm repeatability, +/-10pm accuracy, and 25dB dynamic range with automatic gain and threshold control adjustments. Manual settings option for thresholds and gain stages also included.

Top reliability: The M4-R Interrogator is based on a semiconductor tunable laser that has been deployed in large volume in field applications and features the world’s lowest MTBF. The interrogator has no movable parts, no tunable filters, and no optical switches, which enables top reliability over the standard temperature range of -15C to +55C. The M4-R is also available upon request with -40C to +70C rating. Suitable for use as an integral part of a very rugged and reliable sensing system. Adaptive to more types of sensors: Designed to monitor many types of sensors from narrow bandwidth (100pm) FBGs used in accelerometers and pressure sensors, to wide bandwidth (3.0nm) FBGs used in bio-sensing. Hardware implementation of peak tracking algorithms for FBG sensors included.

The laser output power is <4 dBm and performance is maintained even with 20dB optical power loss on each of the M4-R’s four channels. Systems and network ready: The LINUX based Raspberry PI Processor inside the M4-R interrogator provides the user the ability to turn the M4 interrogator on and off (sleep, wake on clock, wake on LAN), it features RS232 and RS485, an MX interface library, and is an open system for application developers.

Lowest Cost and High Quality: The M4-R Interrogator is based on the company’s solid state instruments platform and it has been optimized to address applications demanding the lowest cost while maintaining the quality and reliability of a high quality instrument. Also available with 8 and 16 channels.

Applications include Security, Civil Engineering, Industrial, Energy, Material Qualification Labs, and Research Centers

Femto Sensing International undertakes a rigorous development process before product release. The company is also firmly committed to continuous improvements after release to ensure performance and reliability to the highest standards, hence, specifications are subject to update without notice.

Femto Sensing International, LLC / 3657 Peachtree Road, Suite 10A, Atlanta, GA, 30319, USA / T: +1 404 326 3469, E: sales@femtosensing.com, W: www.femtosensing.com 

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