Development of a portable SOM detector based on NIR diffuse reflection

• Published in: Guang pu xue yu guang pu fen xi Vol. 30; no. 4; p. 1146
• Main Authors: Li, Min-Zan, Pan, Luan, Zheng, Li-Hua, An, Xiao-Fei
• Format: Journal Article
• Language: Chinese
• Published: China 01.04.2010
• DOI: 10.3964/j.issn.1000-0593(2010)04-1146-05
• ISSN: 1000-0593

A portable soil organic matter detector based on near infrared diffuse reflectance was developed. The detector uses a microprocessor 89S52 as the micro controller unit (MCU) and consists of an optical system and a control system. The optical system includes an 850 nm near-infrared LED lamp-house, a lamp-house driving-circuit, a Y type optical fiber, a probe, and a photoelectric sensor. The control system includes an amplifying circuit, an A/D circuit, a display circuit with LCD, and a storage circuit with USB interface. Firstly the single waveband optical signal from the near-infrared LED is transferred to the surface of the target soil via the incidence fibers. Then the reflected optical signal is collected and transferred to the photoelectric sensor, where the optical signal is converted to the electrical signal. Subsequently, the obtained electrical signal is processed by 89S52 MCU. Finally, the calculated soil organic matter content is displayed on the LCD and stored in the USB disk. The calibration exper