New York City, NY, August 02, 2017/24 Market Reports: A Fiber Bragg Grating (FBG) is a type of distributed Bragg reflector constructed in a short segment of optical fiber that reflects particular wavelengths of light and transmits all others. This is achieved by adding a periodic variation to the refractive index of the fiber core, which generates a wavelength specific dielectric mirror. An FBG is an invisible reflector inside the core of the fiber that is set to a specific wavelength of light. When the fiber where the FBG is located is exposed to strain or temperature, the FBG’s “center wavelength” shifts to a higher or lower wavelength. The direction and magnitude of the shift is proportional to the change in strain or temperature.
A fiber Bragg grating can therefore be used as an inline optical filter to block certain wavelengths, or as a wavelength-specific reflector. Fiber Bragg Gratings are made by laterally exposing the core of a single-mode fiber to a periodic pattern of intense ultraviolet light. The exposure produces a permanent increase in the refractive index of the fiber's core, creating a fixed index modulation according to the exposure pattern. This fixed index modulation is called a grating. At each periodic refraction change a small amount of light is reflected. All the reflected light signals combine coherently to one large reflection at a particular wavelength when the grating period is approximately half the input light's wavelength. This is referred to as the Bragg condition, and the wavelength at which this reflection occurs is called the Bragg wavelength.
Fiber Bragg Grating Filter
Fiber Bragg gratings are versatile wavelength filters for multiplexing and demultiplexing wavelength division multiplexing (WDM) signals. They also can compensate for chromatic dispersion that can degrade the quality of the WDM signal in an optical fiber.
Such a grating is, in fact, a fiber with a core that has a sinusoidal variation of refractive index. This variation affects the phase of light passing through the grating so that some wavelengths interfere constructively and some destructively.
IXFiber Fiber Gain Flattening Filter restores all wavelengths to approximately the same intensity
The high flexible process allows a fast prototype delivery time. Fiber Bragg Grating technology achieves low systematic errors. Chirped and Slanted (iXTra) FBG are performed on internal specialty fiber to achieve High Return Loss and High Frequency Ripple. Furthermore, iXBlue Photonics GFF can be delivered with Polarization Maintaining Fiber (PMF).
Fiber Bragg Grating Sensors
Benefits of FBG-based Sensors
Optical sensors and especially FBG-based ones provide an attractive alternative to traditional electrical sensors for many applications. They have the advantages of high accuracy, long term stability, streamlined installation, and premium performance under harsh environmental conditions. Because optical fiber is essentially a passive, mechanical component of a fiber optic sensor system, it contains neither moving parts nor electrical circuitry and is therefore completely immune to all forms of electrical interference and have extraordinary resistance to mechanical fatigue.
Source: 24 Market Reports