A breathing rate sensor with plastic optical fiber

A breathing rate sensor has been developed using plastic optical fiber and the test results are presented in this letter. The principle of coupling loss was used in designing this sensor to take advantage of the large core size of plastic optic fiber. The sensor was placed near the nostril to determine the rate of breathing as air was exhaled. The results demonstrated the ability to quantify the breathing rate and monitor different breathing patterns up to a resolution of 1 breath/s (1 Hz).