基于氮化镓光电器件的可穿戴健康传感器

       对多种健康指标的持续实时监测在疾病早期和预防阶段有着重大意义，
可穿戴健康传感器由于其易于穿戴和实时监测健康数据的优势而受到极大
关注。为了能准确的监测到微弱的生命信号，本文提出了一种基于氮化镓
（GaN）的单片集成发光二极管（LED）-光电探测器（PD）的光电器件，
同时实现光发射与光探测的功能可以减少复杂光耦合。实现了一种利用蓝
宝石衬底作为光波导的光学传感系统，与传统光学传感系统相比，该系统
具有小型化和高密度集成的优点。 
      本论文提出了一种基于 GaN光电器件的湿度传感器，其传感范围为 2-
90 %RH，响应/恢复时间为 12.5 s/6 s。该传感器在高湿度环境中具有高灵敏度，可用于口罩呼吸监测。设计了柔性无线信号传输电路，可以识别出七
种呼吸模式。此外，本论文提出了一种基于 GaN光电器件的压力传感器，
其传感范围为 0-10 N，响应/恢复时间为 0.84 ms/1.92 ms，最小分辨率为 5 μN。该传感器对微力具有高灵敏度，适用于脉冲监测。设计了柔性多传感器 PCB，通过信号处理可以实现对心率、心率异常、动脉血管硬化和血压的实时监测。

      Continuous real-time monitoring of a variety of health indicators is of great significance in the early stage of disease and prevention, and wearable health sensors have attracted great attention due to their advantages of ease of wearing and monitoring health data in real time. In order to accurately detect weak health signals, this thesis proposes a GaN-based monolithic integrated LED-PD optoelectronic device, which can reduce complex optical coupling by simultaneously implementing the functions of light emission and light detection. 
An optical sensing system using a sapphire substrate as an optical waveguide has been implemented. Compared to traditional optical sensing systems, this system has the advantages of miniaturization and high-density integration.  
      This thesis proposes a humidity sensor based on GaN photoelectric devices, with a sensing range of 2-90 %RH and a response/recovery time of 12.5 s/6 s. The sensor has high sensitivity in high humidity environments and can be used for respirator breathing monitoring. A flexible wireless signal transmission circuit was designed to identify seven respiratory patterns.. In addition, this thesis proposes a pressure sensor based on GaN photoelectric devices, with a sensing range of 0-10 N, a response/recovery time of 0.84 ms/1.92 ms,and a minimum resolution of 5 μN. The sensor has high sensitivity to micro forces and is suitable for pulse monitoring. A flexible multi-sensor PCB is designed to realize real-time monitoring of heart rate, abnormal heart rate, arteriosclerosis 
and blood pressure through signal processing.  

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