Gwybodaeth wyddonol boblogaidd amuwchsain
Whether it's a health check-up or a visit to the hospital, doctors always ask patients to have an ultrasound. Most people's understanding of ultrasound is that pregnant women need B-ultrasound, but in fact, ultrasound is not only used for pregnant women to check the fetus, this is only a small part of the application of ultrasound in clinical medicine. But what exactly is ultrasound? How does it examine the human body?
Ultrasound, that is, ultrasound, is a mechanical wave. The frequency of sound waves that can be heard by the human ear is between 20 and 20 000 Hz. When the vibration frequency of sound waves is greater than 20 000 Hz or less than 20 Hz, we cannot hear them. Therefore, we call sound waves with frequencies higher than 20 000 Hz "ultrasonic". Ultrasonic has the characteristics of good directionality, strong penetrating ability, easy to obtain relatively concentrated sound energy, long distance in water, etc. It can be used for distance measurement, speed measurement, cleaning, welding, gravel, etc., in medicine, military, industry, agriculture widely used.
Yr amledd ultrasonic a ddefnyddir fel arfer ar gyfer diagnosis meddygol yw 210MHz. Gall deithio trwy'r corff ac adlewyrchu rhywfaint ohono yn ôl ar ôl taro meinweoedd gwahanol. Yn ôl yr eiddo ffisegol hwn, mae gwyddonwyr wedi datblygu amrywiol offerynnau ultrasonic. Mae'r don ultrasonic yn cael ei gynhyrchu a'i allyrru gan y stiliwr. Ar ôl mynd i mewn i'r corff dynol, mae rhan o'r ton ultrasonic yn cael ei adlewyrchu yn ôl yn ôl y gwahaniaeth mewn priodweddau acwstig organau a meinweoedd dynol, ac yna'n cael ei dderbyn gan y stiliwr a'i brosesu gan y cyfrifiadur, ei arddangos a'i olrhain ar ffurf tonffurfiau, cromliniau neu ddelweddau. , Ultrasonography yn ddull diagnostig y gall meddyg uwchsain wahaniaethu amodau ffisiolegol a patholegol yn ôl nodweddion y ddelwedd.
