"sine of the angle" . . "Lambertian radiator" . "Lambertian emitter" . . . . "lambertian" . . . "perfectly diffuse" . . "Lambert's Cosine law" . "Lambert's cosine law" . "Lambertian" . . "Lambert'schen Gesetz" . . "Lambert's cosine law" . . "reflection" . . "reflective properties" . "Lambert's_cosine_law" . "Lambert's law" .