Spectrum reflectivity measurer

Abstract

The invention relates to a spectral reflectivity measuring device, which comprises an optical unit, a controlling unit and an ultrasonic ranging unit. Four optical transmitting channels are arranged in the optical unit, two upper channels adopt a cosine scatterer as an optical window, and two lower channels adopt a K9 material optical glass window. The optical window, an optical filter and a plano-convex lens are arranged at one end of the optical unit body, a sealing gasket is arranged on the both sides of the optical filter and the plano-convex lens, and a photosensor is arranged at the focal point of the other end of the plano-convex lens of the optical unit body. The controlling unit comprises a sensor, an amplifier, a digital / analog converter, a single-chip microcomputer, a U disk, a liquid crystal display and a keyboard, etc. The ultrasonic ranging unit consists of an ultrasonic sensing module based on the piezoelectricity principle. The invention achieves that the reflected light of the plant canopy and the radiating light of the sun are measured synchronously, the operational procedure of the measurement is simplified, and the measurement height is kept consistent automatically.

Description

technical field [0001] The invention relates to a sensing technology and a spectral measurement technology, in particular to a spectral measurement technology for the growth status of crops. Background technique [0002] Information such as vegetation growth and nutrition can be reflected in the spectral reflectance. The normalized difference vegetation index NDVI (Normalized Difference Vegetation Index) based on the principle of spectroscopy is widely used as the normalized ratio of the two bands of visible light red band and near infrared band. Used for field crop growth detection. This kind of spectral index reflects the effective radiation absorption of vegetation photosynthesis on the one hand, and reflects the size and health of crop groups on the other hand. It is currently the most widely used vegetation index. [0003] There are several methods for measuring the spectral reflectance of crops. The American ASD (Analytical Spectral Devices) company produces a series...

AI Technical Summary

Problems solved by technology

However, portable spectrometers used in the field are not only expensive, but also cannot directly judge the growth of field crops when used. The staff carry nearly 10kg of instruments on their backs to carry out testing on the spot, which is labor-intensive and inconvenient. There is an urgent need to develop a handheld field crop growth detection The instrument is light in weight and suitable for hand-holding, and can directly judge the growth status of crops during on-site testing

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