What are Lambert's Laws?Asked by: Annemarie Straube
Answer1. The illuminance of a surface illuminated by light falling on it perpendicularly from a point is inversely proportional to the square of the distance between the surface and source.
2. If the rays make an angle x with the normal to the surface, the illuminance is proportional to cos(x).
3. (Also called Bouquer's law) The luminous intensity (I) of light decreases exponentially with the distance d that it enters an absorbing medium i.e. I = Io exp(-z d)
Where Io is the intensity of the radiation that enters the medium and z is its linear absorption coefficient. These laws were first stated (for light) by Johann H. Lambert.
Answered by: Dan Summons, Physics Undergrad Student, UOS, Souhampton