BLACKOUT FABRICS PREVENT LIGHT FROM PASSING.
Optical values are defined according to the European standard EN 14501
OPTICAL INDICES ACCORDING TO STANDARD EN 14501
Visible light transmission (Tv)
The total percentage of light rays on the visible spectrum, with wavelengths ranging between 380 and 780 nm (nanometres), that pass through the tissue.
Visible light reflection (Rv)
The percentage of light rays that are reflected by the fabric.
Light absorption (Av)
The percentage of light rays that are absorbed by the fabric.
By definition, blackout fabric is therefore fabric that does not let any light through. The fabric either absorbs or reflects all the visible light waves.