A driver's physiological monitoring system based on photodiode sensor with reflective optics element

Developing a system to monitor the biological status of a driver is method to increase smart function of car. When the biological condition of driver is unstable, it can sound warning or provide the control strategy not only to reduce the possible damage to the road traffic safety caused by the driver's disablement but also the quantity of the traffic accident. In order to monitor the biological status of the driver in real-time, a continuous and non-invasive sensing system is needed. The method to enhance physiological signals by the designed optical device is the emphasis in this research. A photodiode at the front end presents the less design in optics. For the most part, the light source and the photodiode will directly lighting and receiving on the object without the components to boost the optical signal. Therefore, we develop the optical components that can boost optical signal and light-collecting efficiency, where the component aperture ≤ 5mm and the light-collecting efficiency ≥ 50%. A prototype static error of SpO
₂
: 1% and the heart rate: 1% can monitor and pre-alert the biological status in real-time. If the driver feels the acute discomfort, it can be notified in advance, so as to promote the safety of the road user.