Design Of Wireless Optical Power Meter Based On Internet Of Things

In recent years,under the development of big data and cloud technology,Internet of Things(IoT)technology has become to be more mature.Due to the convenience and high efficiency of the IoT in the measurement field,the modern instrumentation has become more and more intelligent.As a basic device for measuring optical power value and optical attenuation,optical power meter is frequently used in optical experiments and optical communication.However,in the process of laying the communication fiber,it is inevitable to encounter some complicated environments,such as erecting fiber at high altitude,laying fiber on wet muddy ground and so on,which causes great difficulty and inconvenience in detecting optical power.In this thesis,STM32F103ZET6 was used as the main control chip,PIN photodiode was used as photodetector,and NB-IoT module was used as wireless communication.As a result,an optical power meter with IoT wireless transmission was designed and manufactured,which was low cost,high sensitivity,stable performance and easy to carry.In the part of the photoelectric probe,the working principle of the photodetector and the photoelectric conversion laws were discussed firstly.Then the mathematical relationship between the incident light power and the photo-generated current were establish.The PIN photodiode made of silicon was selected as the detector to measure the light power.In the part of data communication,the NB-IoT technology and two key network protocols were used,which including the lightweight CoAP protocol and the LwM2 M protocol.The overall process of connecting the device to the cloud platform and how to develop the wireless optical power meter application were specifically described.So the data collected by the optical power meter can be uploaded to the cloud management platform using the IoT technology.In this thesis,the power meter can measure the laser of 450nm?675nm,1?W?1mW.Through the performance testing,it was proved that the optical power meter could realize the basic requirements.At the same time,all the test results in the test process were uploaded to the Internet of Things cloud management platform through the NB-IoT module.Anyone can log in to the cloud platform to get the data measured by the optical power meter.