For the first time, press the reset key, and the LCD screen will display the standby state. Press the opening clamp. Put the left or right middle finger into the working room (you can see the infrared light in the working room. Note: fingers should not be crooked, hands should not be wet, and there should be no foreign matter on the nail surface). The LCD displays the detection process after the finger is in full contact with the work bin（ Note: enter the detection state, keep the tested fingers stable, do not shake up, down, left and right). After 30 seconds, release the clamp, withdraw the finger from the work bin, and freeze the LCD test results. The% SpO2 at the top of the screen is the blood oxygen index. Min at the bottom of the screen is the pulse rate. From the medical point of view, blood oxygen content (SpO2) greater than or equal to 95 is a normal index; Pulse rate (/ min) is between 60 and 100, which is a normal index. If the values detected by you do not meet the above two indicators, please monitor for 2-3 times at different time points and keep continuous monitoring for 2-3 days. If the values still do not meet the standard values, it is recommended that you go to the hospital for detailed consultation.

The principle of finger type oximeter is based on the absorption spectrum characteristics of reduced hemoglobin and oxygenated hemoglobin in red and near red light regions, and Lambert Beer law is used to establish empirical formula for data processing. The working principle of finger type oximeter adopts photoelectric blood oxygen detection technology combined with volume pulse recording technology. Two different wavelengths of light (660nm red light and 940nm near-infrared light) are used to irradiate the fingernail tip of human body through the perspective clip sensor, and the measurement signal is obtained by the photosensitive element. The obtained information is processed by the electronic circuit and microprocessor, and the measured results are displayed by two groups of LED.