基于近红外光谱技术的便携式水体浊度检测仪研究

Portable Water Turbidimeter Based on NIR Spectroscopy

为了快速准确地探测水产养殖中水体浊度,提出了基于近红外光散射/透射综合测量原理,并在此基础上开发了便携式水体浊度光学检测仪。浊度仪使用AT89S52单片机作为控制芯片,由发光单元、探测单元和控制单元组成。其中发光单元包括2组860 nm的LED光源及对应的准直透镜;探测单元包括2个光电传感器;控制单元包括公共的光源驱动电路、两级放大电路和A/D转换电路。对水体浊度检测仪进行了实验室标定试验、性能试验以及现场采样试验和分析。结果表明,该水体浊度检测仪达到了较高测定精度,其标定决定系数R2c为0.994,验证决定系数R2v为0.999,分辨率为0.01 NTU,误差为±2%,达到实用水平。

Turbidity of water was a very important parameter in aquaculture.An integrated portable turbidimeter was developed to measure turbidity of water body based on the comprehensive measurement method combined scattering light and transmission light.It used AT89S52 microcontroller as control chip and consisted of the light emission unit,detection unit and control unit.The light emission unit comprised two sets of 860 nm LED light source and the corresponding collimating lens.The detection unit comprised two photoelectric sensors.And the control unit included the light source driving circuit,the two-stage amplification circuit and the A/D conversion circuit.The integrated detector was calibrated in laboratory and carried out field experiments.The results showed that the turbidimeter achieved a high accuracy,the calibration Rc2 was 0.994 and the validation Rv2 was 0.999,with the resolution of 0.01 NTU and the error of±2%.It was concluded that the turbidimeter reached the practical level.