radiant exitance (at a point of a surface) [*M*_{e}]

1. quotient of the radiant flux, d*Φ*_{e}, leaving an element of the surface containing the point, by the area, d*A*, of that element

2. equivalent definition: integral, taken over the hemisphere visible from the given point, of the expression *L*_{e}cos*θ*d*Ω*, where *L*_{e} is the radiance at the given point in the various directions of the emitted elementary beams of solid angle, d*Ω*, and *θ* is the angle between any of these beams and the normal to the surface at the given point

Unit: W·m^{-2}

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer