indirect flux, <on a surface>
luminous flux received by the surface from a lighting installation, after reflection from other surfaces
Note 1 to entry: The indirect flux is expressed in lumen (lm).
Note 2 to entry: This entry was numbered 845-09-45 in IEC 60050-845:1987.
Note 3 to entry: This entry was numbered 17-573 in CIE S 017:2011.