The invention of optical fiber and semiconductor lasers in the 1960s opened new applications in communications and sensing.
Optical fibers provide a fundamental improvement over traditional methods offering lower loss, higher bandwidth, immunity to electromagnetic interference, lighter weight, lower cost, and lower maintenance. By applying a UV laser to “burn” or write a diffraction grating (a Fiber Bragg Grating – FBG) in the fiber it became possible to reflect certain wavelength of light, which used together with an interrogation analyzer precise sensing measurements could be taken. This technology is widely used for Dense Wavelength Division Multiplexing (DWDM) applications, for real time fault detection and imbedded monitoring of smart structures (stress measurement).
Applied Infrared Sensing launches new Fiber Bragg Grating Analyzers (FBGA) from BaySpec (USA). These FBGA employ a highly efficient Volume Phase Grating VPG® as the spectral dispersion element and an ultra sensitive InGaAs array detector as the detection element, thereby providing high-speed parallel processing and continuous spectrum measurements. As an input, the device uses a tapped signal from the main data transmission link through a single mode fiber, then collimating it with a micro lens. The signal is spectrally dispersed with the VPG®, and the diffracted field is focused onto an InGaAs array detector. The control electronics read out the processed digital signal to extract required information. Both the raw data and the processed data are available to the host.
FBGA are available in two versions: a standard high speed FBG analyser and an infrared FBG analyser. Both FBG analysers represent integrated spectral engines with an internal reference source that interrogates multiple wavelengths for precise fiber bragg grating (FBG) sensor system measurements requiring high end of life wavelength accuracy at high frequency response time. The devices cover wide wavelength ranges and provide simultaneous measurements at very fast response rates and excellent wavelength resolution.