| 摘要 |
PURPOSE:To detect accurately the radial rotation standard position and the amt. of forwarding and retreating in the linear direction of an ultrasonic oscillator and to improve the image quality of radial display, linear display or three- dimensional display of a B mode image by using a simple constitution. CONSTITUTION:The angle of stopping is different and the period of generation of a pulse line (PtA and PtB) is changed in accordance with the position of a cross-section to be scanned by an ultrasonic oscillator 2 and by a sound reflecting body 6 having a shape of isosceles triangle with an apex in the forwarding and retreating direction, and this period of generation (PtA and PtB) is counted by a CPU. In addition, by comparing the counted value with the shape data of the sound reflecting body 6 by using the CPU and by calculating which cross-section of the sound reflecting body 6 the ultrasonic oscillator 2 passes through now, a radial rotation standard position and the amt. of forwarding and retreating in the linear direction of the ultrasonic oscillator 2 provided on the apex of a flexible shaft is accurately detected. |
