Calculate the optical efficiency of any reflector design — from material reflectance and number of inter-reflections to aperture ratio and total lumen delivery. Compare reflector materials side by side and estimate luminaire LOR (Light Output Ratio) for LED downlights, spotlights, and industrial fixtures.
Reflector material
Specular aluminium
rho = 88%
Semi-specular aluminium
rho = 83%
White painted / matt
rho = 90%
Anodised aluminium
rho = 80%
Silver mirror film
rho = 95%
Custom / other
enter below
From material datasheet — at 45° incidence angle
Optical geometry
% of source flux intercepted by reflector
Fraction of flux going directly to aperture
100% if no glazing; 88-95% for glass/acrylic
Light source
Bare LED or lamp output before reflector
LED module efficacy — for system lm/W
Please enter reflectance and source lumens.
Reflector optical efficiency (LOR)
0%
0 lm
Delivered lumens
0 lm
Lost to reflector
0 lm/W
System efficacy
0%
Total system LOR
Lumen loss waterfall — source to delivered
Reflector geometry — light path
Material comparison — same geometry, different reflectance
MaterialrhoLORDelivered lmvs selected
Reflector type guide
Optimising reflector efficiency
Material reflectance
Average reflections
Reflected component efficiency
Direct component
Glazing transmission
Maintenance factor
Overall LOR
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