converging rays
Webster's Dictionary (GCIDE)
Converging \Con*ver"ging\, a. Tending to one point; approaching each other; convergent; as, converging lines. --Whewell. [1913 Webster]
Converging rays(Opt.), rays of light, which, proceeding from different points of an object, tend toward a single point.
Converging series (Math.), a series in which if an indefinitely great number of terms be taken, their sum will become indefinitely near in value to a fixed quantity, which is called the sum of the series; -- opposed to a diverging series. [1913 Webster]