Meanings
- engineeringA law stating that the radiant intensity or luminous intensity observed from an ideal diffusely reflecting surface or ideal diffuse radiator is directly proportional to the cosine of the angle between the direction of the incident light and the surface normal.
Synonyms: cosine emission law, Lambert's law, Lambert's emission law
Synonyms & antonyms
proper nounA law stating that the radiant intensity or luminous intensity observed from an ideal diffusely reflecting surface or ideal diffuse radiator is directly proportional to the cosine of the angle between the direction of the incident light and the surface normal.
Origin
Named after Johann Heinrich Lambert.
Full word history & related roots →Cite this entry
Lambert's cosine law. (n.d.). In WatkinsX Dictionary. Retrieved November 5, 2026, from https://dictionary.watkinsx.com/word/Lambert's%20cosine%20law
“Lambert's cosine law.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Lambert's%20cosine%20law. Accessed November 5, 2026.
WatkinsX Dictionary, s.v. “Lambert's cosine law,” accessed November 5, 2026, https://dictionary.watkinsx.com/word/Lambert's%20cosine%20law.
Source: Lambert's cosine law on Wiktionary, CC BY-SA 4.0.