With the influx of intelligent waves, smart wearable devices are ushing in a rapid development period. While the wearables such as smart bracelets, smart watches and smart rings are emerging endlessly, the functions of the products are constantly improving, such as more and more. Heart rate monitoring is standard on all products. Nowadays, the heart rate monitoring function of intelligent wearable products represented by smart bracelets and smart watches is being accepted by more and more people, and even some people have already regarded it as one of the necessary functions for selecting products. So how does smart wearables monitor heart rate? Today, let’s talk about heart rate monitoring. Why measure heart rate? As one of the most important vital signs of the human body, each person's heart rate will vary according to age, gender and other physiological conditions. In general, the average heart rate of a normal adult is about 75 beats / min (60 to 100 beats / min). In the same person, when the heart rate is slow or sleep, the heart rate is slowed down, and the heart rate is accelerated during exercise or emotional excitement. Under the influence of certain drugs or neurohumoral factors, the heart rate may be accelerated or slowed down. People who often perform physical labor and physical exercise usually have a slow heart rate. Specifically, the factors affecting heart rate changes are mainly three major regulatory systems, namely, self-regulation, fluid regulation, and neuromodulation. Changes in heart rate can directly or indirectly reflect the various aspects of the body's health, which is the significance of measuring heart rate. In the field of smart wear, the significance of measuring heart rate is mainly reflected in three aspects. The first is sports. The heart rate can reflect the real information of the user during exercise. If the heart rate is too high, the exercise is too intense, and the user's body water evaporates too quickly. This kind of exercise is not good for the body. If the heart rate is only low, the user is not high enough. It is impossible to burn enough calories. Secondly, in terms of diseases, monitoring the resting heart rate in the normal range, monitoring cardiac arrest during daily activities, abnormally increased heart rate, etc. can play a role in preventing diseases in a timely manner, and even detecting heart rate through ECG can detect abnormal heart rhythm. In addition, pulse wave changes can be monitored by fingertip photoplethysmography to analyze pulse rate, blood oxygen concentration, microcirculatory peripheral vascular status in diabetic patients, and the like. Finally, the mental aspect, through the monitoring of heart rate variability, can analyze autonomic function assessment, such as mental stress, tension and relaxation, and sleep quality. How is heart rate monitoring achieved? As an emerging product of the 21st century, smart wearable products, due to its specific use scenarios and wearing requirements, the heart rate monitoring technology applied in this field currently mainly has photoplethysmography, which is called photoelectric method, ECG signal method, pressure oscillation. Law, image signal analysis and other categories. Photoelectric method Simply put, this method of measuring heart rate is based on the principle of absorption of light by matter. The green LED lamp of the smart wearable device is used to illuminate the blood vessel with the photodiode for a period of time. Since the blood is red, it can reflect the red light. In green light, when the heart beats, the blood flow increases, and the absorption of green light will increase. When the heart beats, the blood flow will decrease and the absorbed green light will decrease. Therefore, the heart rate can be measured based on the absorbance of blood. Specifically, when a beam of a certain wavelength is irradiated onto the surface of the skin, the beam will be transmitted to the photoreceiver by transmission or reflection. In the process, the detector monitors the intensity of the light due to the attenuation of skin muscle and blood absorption. Will be weakened. The skin, bones, meat, fat, etc. of the human body reflect the light at a fixed value, while the capillaries and arteries and veins become larger and smaller with the pulse volume under the action of the heart. When the heart contracts, the peripheral blood volume is the largest, the light absorption is also the largest, and the detected light intensity is the smallest. When the heart is dilated, on the contrary, the detected light intensity is the largest, so that the light intensity received by the light receiver is followed. A pulsating change. Real Cinnamon Powder,Cinnamon Extract Powder,Bulk Cinnamon Powder,Cinnamomum Powder jiangmen city hongsing food co., ltd. , https://www.jmhongsing.com![[Popular] Explain the principle of heart rate monitoring for smart wearable medical devices](http://i.bosscdn.com/blog/71%20(1).jpg)
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