Finger recognition method of reflectance oximetry

Abstract

The invention discloses a finger recognition method of a reflectance oximetry, and belongs to the field of medical instruments. The finger recognition method mainly comprises the following steps: I, converting an optical signal received by a receiving sensor when the optical signal is transmitted by a transmitting sensor into a frequency signal, then comparing with a preset light intensity threshold value, and judging whether the light environment is a weak light environment or a strong light environment; II, analyzing a frequency signal formed by the light signal received by the receiving sensor at the time of double pulse square wave high level and a frequency signal formed by the light signal received by the receiving sensor at the time of double pulse square wave low level according to a result obtained by the step I to judge whether a finger exists; III, determining whether the reflectance oximetry is started. According to the method, the reflectance oximetry can be accurately, reliably and automatically opened, the design is simpler, the circuit is easier and more convenient, and the service life of the oximetry can be prolonged.

Description

technical field [0001] The invention relates to a method for identifying fingers by a reflective oximeter, which belongs to the field of medical devices. Background technique [0002] The blood oxygen meter can be used to detect the blood oxygen saturation of the human body. By detecting the ratio of the absorbance change rate of the peripheral tissues of the human body, such as fingers and earlobes, to different wavelengths of red light and infrared light, the arterial blood of the peripheral tissues can be calculated. oxygen saturation. [0003] The reflective oximeter has two or more sensors in the same plane. The transmitting sensor will send out a light signal when it receives the light-emitting pulse command, and the emitted light will illuminate the finger surface vertically. Underneath, the light shines into the finger and enters the receiving sensor in a reflective manner; the receiving sensor is a photoelectric sensor that converts light signals into electrical si...

AI Technical Summary

Problems solved by technology

The method of identifying the finger by setting the button circuit not only needs to increase the cost of the button circuit, but also due to the aging of the button or the circuit device, the finger recognition function will fail, resulting in the inability to start the collection

Images