Study on respiration monitoring method using near-infrared multiple slit-lights projection

We describe the principle of the respiration monitoring by the multiple slit light irradiation and the configuration of the respiration monitoring system. In the developed system, the fiber grating vision sensor known as an active type high-speed three-dimensional sensor was applied to satisfy the non-contact and non-restraint respiration monitoring. The fiber grating vision sensor is composed of a multiple slit light projector and a CCD camera, and these are placed above the sleeping person oriented in a lengthwise direction of the bed. And the multiple slit light projector projects the slit light array on the body surface of sleeping person. In this paper, the algorithm for monitoring and analyzing of the respiration status of the sleeping person is proposed. And, the result of the preliminary experiment performed to verify the effectiveness of developed system is described. As results of preliminary experiment through the simultaneous measurements with the developed system and a spirometer, it is confirmed that respiratory waveforms obtained by this system reflect the changes of volume occurring with respiratory movement of the examinee.