The working principle of a stethoscope is to use vibration conduction between substances to change the frequency and wavelength of sound through the aluminum film in the stethoscope, so that the sound reaches the "comfortable" range of the human ear, while shielding other sounds, so that it can be "heard" more clearly.
Specifically, a stethoscope consists of a sound pickup part (chest piece), a transmission part (hose), and a listening part (ear piece). The chest piece collects sounds in the human body, such as heartbeats and breathing sounds, which are transmitted to the ear piece through the hose. During the transmission process, the frequency and wavelength of the sound will change, making it easier for the human ear to hear these sounds. At the same time, the stethoscope can also shield the surrounding environmental noise, allowing people to listen to the sounds in the body more attentively.
There are many types of stethoscopes, such as bell-shaped chest pieces and membrane-shaped chest pieces. Bell-shaped chest pieces are suitable for listening to low-frequency sounds, such as diastolic murmurs of heartbeats; membrane-shaped chest pieces are suitable for listening to high-frequency sounds, such as breathing sounds.
The stethoscope is one of the important tools for doctors to make diagnoses, but it also has certain limitations. For example, for some deep tissues or organ sounds, the stethoscope may not be able to hear clearly. In addition, the use of the stethoscope requires certain skills and experience, and the doctor needs to choose the appropriate stethoscope and auscultation site according to different situations.
