The Blondel ( unit symbol: blondel ) in 1942 proposed self-luminous body as the name for the unit of luminance.
The unit is defined identically to apostilbes, the name was chosen to commemorate the French physicist André -Eugène Blondel. The unit is now considered outdated, or use a formal assessment of the unit of measurement is not detectable. 1948 was established by the General Conference on Weights and Measures, the candela as the name for the measure of light intensity.
1 blondel = 1 apostilbes = 1 / π · 10-4 candelas / meter ²
1 blondel therefore corresponds to π lumens per steradian per square meter