| 摘要 |
PROBLEM TO BE SOLVED: To embody a transmission convergence as against whole video points by searching a transmitted pulse-shaped planar wave having the same video point from the video points which are calculated in a stage for calculating the video points where the respective pulse-shaped planar waves to be transmitted arrive at. SOLUTION: In an ultrasonic video system, data as against a directional angle θand a transmission spot x is stored and respective reception signals returned after the transmitted pulse-shaped planar waves arrive at an optional video depth z and are reflected and also a reciprocative time 2t till the optional video depth are stored. Then, the directional angle θ, the transmission spot z and the reciprocative time 2t stored as against the transmitted pulse-shaped planar waves are substituted in the formula so that the video depth z obtained by the arrival of the transmitted pulse- shaped planar waves is obtained. Thus, the video points x and z where the planar waves arrive at are obtained. Then, the pulse-shaped planar waves having the obtained same video points x and z are linearly superimposed. In the formula, c is the speed of the pulse-shaped waves, β is sin θ and υ is cos θ. |
