(A=abc or A=bc) Beer-Lambert law. In absorption spectroscopy, the absorbance of a dilute solution is equal to its absorptivity times the path length times the concentration of the absorbing solute.
(from the article `colorimetry`) ...laws are applied: that of a French scientist, Pierre Bouguer, which is also known as Lambert`s law, relates the amount of light absorbed and the ... ...into 1.7 yields an attenuation, or extinction, coefficient for available light as averaged over the Secchi disk depth. The light extinction ... ......
(Beer-Lambert law)
The intensity of a colour or of a light ray is inversely proportional to the depth of liquid through which it is transmitted; it is concluded that the absorption is dependent upon the number of molecules in the path of the ray. ... Compare: Beer-Lambert law. ... (05 Mar 2000) ... 
Describes the mathematical relationship between the absorption of light energy relative to the concentration of a dye or pigment.