Design of Portable SPAD Value Chlorophyll Content Detector

Yusen Yang ； Dongcai Xie

《International Core Journal of Engineering》 8卷8期 (2022/08) Pp. 916-921

https://doi.org/10.6919/ICJE.202208_8(8).0126

摘要

A simple and portable SPAD chlorophyll content detector with STM32F103ZET6 as the main controller was designed, with real-time monitoring function of temperature and humidity and time display function. The relative content of chlorophyll-SPAD value was detected by photoelectric nondestructive testing method, and the rapid and nondestructive measurement of chlorophyll content in leaves was carried out. Principle: Calculate the SPAD value by comparing the changes in the intensity of red light with a wavelength of 650nm and infrared light with a wavelength of 940nm when there are leaves or not; At the same time, the temperature and humidity value at that time is monitored by the temperature and humidity sensor, and the RTC module of the main controller is used to accurately display the measurement time, which is convenient for users to record the measurement information; in addition, a simple power supply circuit is designed, which is convenient for carrying work in the field. This design solves a series of problems such as mobile power supply and light source control, and uses common chips, which are low in cost and easy to replace. The design scheme achieves good design indicators.

關鍵字

Chlorophyll Content ； Photoelectric Detection ； Mobile Power Supply

參考文獻

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