Abstract: A real time digital reception focusing apparatus calculates a focusing delay time using information on the center of array transducing element, a corresponding transducing element and a scan line. The focusing delay time with respect to each transducing element is calculated by each transducing element. To calculate the focusing delay time on a real time basis, first coefficient signals output from a plurality of coefficient generators which are disposed in parallel are input to a first multiplexer. The first multiplexer selects one among the first coefficient signals according to a select control signal corresponding to a present decision variable signal. The decision variable signal with respect to the present focal point output from the decision variable generator is used for generation of a decision variable signal in the next focal point.