Dual Band Bend Insensitive Fiber

These germanium doped Single-Mode (SM) fibers offer excellent performance in applications where the fiber will be subjected to tight bends. This is compliant to ITU standard G657.B3.

Fibercore’s range of SM1250B3 products come in either 125μm or 80μm cladding diameter. Whilst both cladding variants provide bend performance comparable to the ITU-T standard G.657.B3, the 80μm cladding diameter offers improved mechanical lifetime for the most extreme bend diameter requirements, for example; transceiver in and out coupling fibers, hydrophones, geophones and biomedical applications.

Fibercore has developed a unique carbon coating, which offers significant barriers against hydrogen, moisture fatigue and acid ingression. The carbon coating also increases the lifetime of a fiber under tight and sharp bends, protecting the fiber from water/moisture attack/(micro cracking) to the fiber glass surface.  This is an optional coating that can allow the user to take full advantage of the bend performance while not risking long term fatigue failure. 

These fibers are available with acrylate, high temperature acrylate, polyimide, carbon & high temperature acrylate and carbon & polyimide to cover the a temperature range up to 300C .

  • Low weight/small size avionics cables
  • Data center transceivers
  • Oil & Gas distributed sensors
  • Silicon photonics
  • Well integrity monitoring
  • FBGs for strain and temperature monitoring where tight bends are required

    Operating Wavelength (nm)1310-16251310-16251310-16251310-1625
    Cut-Off Wavelength (nm)1100-12601100-12601100-12601100-1260
    Numerical Aperture0.
    Mode Field Diameter (μm)7.6-9.1@1310nm & 8.5-10.0@1550nm8.0-9.2@1310nm & 9.0-10.4@1550nm8.0-9.2@1310nm & 9.0-10.4@1550nm8.0-9.2@1310nm & 9.0-10.4@1550nm
    Attenuation (dB/km)≤0.7 @1310nm & ≤0.5 @1550nm≤0.6 @1310nm & ≤0.4 @1550nm≤0.6 @1310nm & ≤0.4 @1550nm≤0.6 @1310nm & ≤0.4 @1550nm
    Proof Test (%)2 (200 kpsi)2 (200 kpsi)2 (200 kpsi)2 (200 kpsi)
    Cladding Diameter (μm)80 ± 1125 +/- 1125 +/- 2+/-1
    Core Cladding Concentricity (μm)≤1.0≤1.0≤1.0≤1.0
    Coating Diameter (μm)170 ± 5High Temperature: 245 ± 15Carbon High Temperature: 245 ± 15Polyimide: 155 ± 5
    Coating Type*Dual Layer AcrylateHigh TemperatureCarbon High TemperaturePolyimide
    Operating Temperature (ºC)-55 to +85High Temperature: -55 to +150Carbon High Temperature: -55 to +150Polyimide: -55 to +300
    Bend Induced Attenuation @1550nm (dB/turn)
    10mm Bend Radius0.03≤0.03≤0.03≤0.03
    7.5mm Bend Radius0.08≤0.08≤0.08≤0.08
    5mm Bend Radius0.1≤0.15≤0.15≤0.15
    Product Variants Explained

    SM bend insensitive fiber with a 9.3μm core and a 80μm cladding


    SM bend insensitive fiber with a 9.8μm core and a 125μm cladding.


    Operating Wavelength (nm) 1310 - 1625
    Cut-Off Wavelength (nm) 1100 - 1260
    Numerical Aperture 0.13
    Mode Field Diameter (μm) 7.6 - 9.1 @1310nm
    8.5 - 10.0 @1550nm
    Attenuation (dB/km) ≤0.7 @1310nm
    ≤0.5 @1550nm
    Proof Test (%) 2 (200 kpsi)
    Cladding Diameter (μm) 80 ± 1
    Core Cladding Concentricity (μm) ≤1.0
    Coating Diameter (μm) 170 ± 5
    Coating Type Dual Layer Acrylate
    Operating Temperature (°C) -55 to +85
    Bend Induced Attenuation @1550nm (dB/turn) 10mm Bend Radius: 0.03
    7.5mm Bend Radius: 0.08
    5mm Bend Radius: 0.10