back reflection

In optical fiber installation, referring to light reflected back toward the source from the

air gap at the point where two fiber endfaces meet in a connector. There is always a slight air gap, as the endfaces are never perfectly cleaved and never can be aligned in the connectors so that they mate perfectly.

The considerable difference in index of refraction (IOR) between glass and air causes some amount of light to reflect. An angled physical contact (APC) connector, which joins two fiber endfaces at a slight angle, sometimes is used to minimize attenuation and back reflection. See also APC, attenuation, backscatter, connector, IOR, and optical fiber.

• Table I-4: Selected ITU-T I-Series Recommendations
• Table I-4: Selected ITU-T I-Series Recommendations (continued)
• Table I-5: ITU-T Series Recommendations
• Table J-1: Japanese Digital Hierarchy: J-carrier
• Table L-1: Longitudinal Redundancy Check (LRC)
• Table M-1: International Morse Code
• Table O-1: OSI Reference Model Layers
• Table O-2: G.709 Line Rates and Corresponding SDH/SONET Line Rates
• Table P-1: Evolution of PBX technology
• Table P-2: Military and Aviation Phonetic Alphabet
• Table Q-1: Selected ITU-T Q-Series Recommendations
• Table R-1: Before and After: Bell Operating Companies (BOCs) and Regional Bell Operating
• Table R-1: Before and After: Bell Operating Companies (BOCs) and Regional Bell Operating
• Table R-2: Coaxial Cable Types
• Table S-1: SDTV Scanning Formats
• Table S-2: SONET/SDH Signal Hierarchy
• Table T-1: North American Digital Hierarchy: T-carrier
• Table T-2: TCP/IP Protocol Suite
• Table V-1: Electromagnetic Signal Propagation Velocity (Approximate)
• Table V-2: Vertical Redundancy Check (VRC)
• Table V-3: Selected ITU-T V-Series Recommendations
• Table W-1: ITU-T Transmission Windows
• Table X-1: DSL Technology Comparisons
• Table X-2: ITU-T X Series Recommendation Groups
• Table X-3: Select X Series Recommendations