SWDM Technology
Fibrain family SWDM series of multiplexers is produced using the FBT (Fused Biconical Tapering) technology that is based on fusing narrowed cores of optical fibers. They are the simplest optical filters used for WDM transmission. They are characterized by large resistance to varying conditions in external networks, low insertion and reflection losses. These devices are designed for separation of optical signals transmitted at different wavelengths.


  • High thermal stability of parameters
  • Low insertion and polarization dependent loss
  • High channel isolation
  • WDM systems
  • Telecommunication networks
  • CATV networks
  • Optical amplifiers
  • Measuring equipment
Technical Data
Example technical specification for a WDM 1310&1550 nm filter
Type 1310/1550 nm
Wavelengths [nm]  1310 and 1550 nm*
Bandwidth [nm] ± 15
Attenuation [dB]  Standard: 0.35
 Premium: 0.20
Isolation [dB] Standard ≥ 16
Premium ≥ 17
PDL [dB] 0.10
Directivity [dB] ≥ 55
Thermal stablity 0.002 dB/0C
Temperature operating range -200C to +700C

* Other wavelengths available upon request.

Notice: Parameters listed in the table refer to components without connector terminations.

  • Output fibers in 250/900 μm coating: Ø55x3.0 or Ø60x3.0 mm
  • Output fibers in 0.9/2.0/3.0 mm coating: blackbox 90x20x10 mm