Fiber Loss Calculators
Always use the same units (inches or mm) in each calculation (unless indicated).
Enter your numbers into the 'recessed' cells. Press the TAB key to recalculate.
Other formulas you'd like to see? Todd@fiberopticsystems.com
	Glass	Fused Silica	Plastic
Typical Index of Refraction	1.58	1.46	1.49
Typical Attenuation (dB/Meter)	0.67	0.01	0.27
Actual index and attenuation values depend on wavelength and are available from the manufacturer.
Fiber Internal Transmission	Fiber Length (Meters)	Attenuation (dB/m)	Total Internal Tx (%)
(Three calculations provided for comparison)
Internal Transmission is the loss within the fiber itself.
Surface Reflection Loss at Normal Incidence	Index of Refraction	Air Index	% Loss/ Surface	% Tx	dB Loss/ Surface	%Tx 2 Surfaces
Reflection losses can be reduced with Anti-Reflection coatings or Index Matching Gel.
Fiber Bundle External Transmission	Packing Fraction (85% Typ)	Clad Diameter (um)	Core Diameter (um)	Clad/Core Area Ratio	Reflectivity (Tx2 from above)	Total Internal Tx (from above)	Total External Tx (%)
(Three calculations provided for comparing fiber diameters and attenuation)
External Transmission includes packing, cladding, reflection, and fiber losses. Packing refers to the interstitial areas of the bundle.
Convert Feet	Feet	Inches	mm	Meters
Convert mm	mm	Inches	Feet	Microns
Convert meters	Meters	Feet	Inches	mm

Automatic recalculation