Bill Lambert's Law

Bill Lambert's Law, also known as Bill's law or the Law of Beer–lambert (Beer's Law), Lambert-Bill, and Bug-Lambert-Bill law, is the Basic Law of light absorption, Suitable for all electromagnetic radiation and all light-absorbing substances, including gases, solids, liquids, molecules, atoms and ions. The law of Bill Lambert is the quantitative basis of absorbance spectrophotometry, colorimetric analysis and photoelectric colorimetric method.
A beam of monochromatic light irradiation on the surface of a absorbing medium, after a certain thickness of the medium, because the medium absorbed a part of the energy, the intensity of transmission will be weakened. The greater the concentration of the absorbing medium, the greater the thickness of the medium, the more significant the weakening of the light intensity, the relationship is:

The quantitative relationship between light absorption of matter has long been noted by scientists and studied. Pierre Bougg (Pierre bouguer) and John Heinrich Lambert (Johann Heinrich Lambert) clarified the relationship between the absorption degree of light and the thickness of absorbing medium in 1729 and 1760 respectively. 1852, Auschwitz · Bill (August Beer) also suggested that the absorption of light and the concentration of light-absorbing substances have a similar relationship, the two combined to obtain the Basic Law of light absorption--the law of the bug-Lambert-bill, called the bill-Lambert law.

Bill Lambert's Law