optical density:

More on optical density from Fact Monster:

• refraction - refraction refraction, in physics, deflection of a wave on passing obliquely from one transparent ...
• refraction: The Nature of Refraction - The Nature of Refraction Refraction is commonly explained in terms of the wave theory of light and ...
• refraction: The Law of Refraction - The Law of Refraction The law of refraction relates the angle of incidence (angle between the ...
• Encyclopedia: Physics - Encyclopeadia articles concerning Physics.

See more Encyclopedia articles on: Physics