人的听觉范围约自每秒15周到每秒20,000周;频率超过每秒20,000周的音波,人类耳朵不能听到,故称为超音波。超音波有—种特性,即当超音波由一种介质穿入到另一种介质时,就会产生反射波。作者利用此种性能来测定脑瘤肿的部位。作者的实验是这样的,在一个脑瘤女性患者死亡以后,立即取出脑子;脑子外表完全正常,作者乃将特制的超音波探测仪经过脑的表面发射脉动性超音 Human hearing range from about 15 weeks to 20,000 seconds per second; frequency of more than 20,000 weeks per second sound waves, human ears can not hear, it is called ultrasound. Ultrasound has - a characteristic, that when the ultrasound from one medium into another medium, it will produce reflected waves. The authors use this property to determine the location of a brain tumor. The author’s experiment is this, in a brain tumor of female patients died immediately after the brain was removed; the brain appearance is completely normal, the author is a special ultrasonic detector through the brain surface emission of pulsating ultrasound