I-MON Interrogation Monitors
I-MON Interrogation Monitors for FBG Sensing Systems
Ibsen Photonics' I-MON Interrogation Monitors set new standards for fast, real-time spectrum monitoring of FBG sensor systems.
Through a unique combination of very fast measurement frequency, low power consumption and compact size, they are ideally suited for a broad range of applications. The I-MONs offer straightforward integration and meet industrial qualification standards.
Principle
The FBG sensor is a short piece of optical fiber with a periodic modulation of the refractive index in the optical fiber. The periodic modulation of refractive index is generated by the interference pattern created from the phase mask, and it creates a narrow filter response with peak reflectivity at a wavelength determined by the period of the FBG.
A broadband source such as a superluminescent diode (SLED) or an amplified spontaneous emission (ASE) source can be used as light source for the FBG sensing system.
When the FBG is mounted on a structure it may be stretched or compressed due to structural changes of the structure. This causes a change in the FGB period, and the peak reflectivity of the FBG is shifted accordingly to λi+Δλ. Each fiber can contain a multitude of FBG sensors all having different peak reflection wavelength.
Determining the peak reflection wavelength and shift in peak wavelength is the basis of FBG sensing, since measurement of the reflected wavelength can be converted to parameters such as strain, pressure, vibration and temperature. The I-MON Interrogation Monitors are designed to measure the reflection spectra from the FGB sensors, and will provide data to the control electronics or PC for peak determination.
Features
The compact size and simple electronics interface makes the I-MON Interrogation Monitors ideal for direct mounting on the customer's interrogation system control PCB.
The I-MON series has the following features:
- Fast measurement frequency
- Compact size
- Low power consumption
- No moving parts
- Environmentally stable fused silica gratings
Applications
FBG sensing:
- Vibration analysis
- Temperature measurements
- Pressure monitoring
- Strain measurements
Product overview
Below is an I-MON product overview - you can also access these conveniently through the navigator.
- I-MON 80D Interrogation Monitor
- The I-MON 80D is an OEM device designed for integration with the customers control PCB together with a light source suitable for the FBG sensor design. The I-MON 80D is well-suited for high-speed applications with a limited number of FBG sensors.
- I-MON 80D-R Reprogramming Kit
- The I-MON 80D-R is a reprogrammable version where the read-out wavelength range can be reduced with corresponding increase in measurement speed. Several 10’s of kHz measurement speed can be achieved still maintaining sub-picometer resolution.
- I-MON E Interrogation Monitor
- The I-MON E is a high-resolution interrogation monitor with USB interface and data acquisition software providing easy setup with a laptop. The I-MON E is well suited for high accuracy applications with many FBG sensors.
- I-MON 850 Interrogation Monitor
- The I-MON 850 is a high-resolution interrogation monitor for FBG sensing in the 850 nm wavelength range. The I-MON 850 also allows extremely fast sensing though a 15 kHz line scan option.
- I-MON 256 OEM Interrogation Monitor
- The I-MON 256 OEM is a cost efficient and high resolution interrogation monitor for FBG sensing in the 1550 nm wavelength range. The I-MON 256 OEM is intended for OEM integration into FBG sensing systems and allows extremely fast sensing though an up to 20 kHz line scan option.
- I-MON 256 HS Interrogation Monitor
- The I-MON 256 HS Interrogation Monitor offers real-time spectrum monitoring of FBG sensors in the full 1525 - 1570 nm wavelength range at line scan rates up to 17 kHz. A GigE interface and a data acquisition software enables plug-and-play operation for integrators of FBG sensing systems.
- DL-BP1-1501A SLED lightsource
- Broadband 1550 nm SLED light source integrated with optical circulator. USB interface for software control.
I-MON Customization
The I-MON design and specifications can be modified to suit a range of customer requirements.


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