DEVELOPMENT OF HIGH FREQUENCY ULTRASOUND USING SAPHIRE FIBERS AS WAVE GUIDE

(1)研究了用直径为100-200 μ m的蓝宝石光纤传输频率从几MHz到200 MHz的超声波的方法。光纤中的传播损耗极小。提出了一种从大直径换能器到光纤的转换方法。(2)获得了发展活检型显微镜的初步结果。将置于体外的换能器激发的超声波通过光纤作为波导传输到组织中。(3)研制了一种用于血管内超声（IVUS）的以螺旋线圈为定子的超声电机。电机的结构非常简单。因此，该电机可用于医疗工程以及工业工程。(4)构建了用于IVUS的初步系统并获得了图像。该系统采用了先进的超声波电机。(5)提出了一种用于导管内超声成像的脉冲压缩方法中压缩脉冲旁瓣电平的抑制方法。

(1) Transmission method of ultrasonic wave in the frequency range from few MHZ to 200 MHz using a sapphire fiber with diameters 100-200 microns was developed. The propagation loss in the fiber is extremely small. A conversion method from a transducer with a large diameter to the fiber was developed.(2) Preliminary results for the development of a biopsy-type microscopy were obtained. The sappire fiber was used as a waveguide to transmit the ultrasonic wave excited by the transducer placed outside the body to the tissue.(3) An ultrasonic motor using a helical coil as a stator was developed for IVUS(intravascular ultrasound). The structure of the motor is very simple. Therefore this motor may be used in medical engineering as well as industrial engineering.(4) Preliminary system for the IVUS was constructed and an image was obtained. The system incorporates the developed ultrasonic motor.(5) A method suppressing sidelobe level of the compressed pulse in pulse compression method in an intraductal ultrasonic imaging method was developed.