Soil Near Infrared Composition Detection Apparatus Design

摘要

In this paper, we focus on the needs for realizing fast and nondestructive measurement of total nitrogenand organic matter content in the soil, designed a near infrared soil component content detectionapparatus. The reflected light intensity, which carried the sample internal characteristic information,was measured the total nitrogen and organic matter content indirectly. The structure of the paper is asfollows: First of all, designed the system hardware part with the Czerny-Terner grating splitting opticalpath. The apparatus hardware consisted of mainly light path and electrocircuit. The light path includedlight source, spectral element and photoelectric conversion element. The electrocircuit part includedamplifies, filters and A/D converts. The diffuse light was converted to electrical signal by thephotoelectric conversion element, and then the digital signal was displayed, stored. Secondly, using thepartial least square method to establish soil component content near infrared application model.Finally, the performance of the apparatus was verified with soil samples test. The experimental resultsshowed that: near infrared reflectance and the soil total nitrogen and organic matter content hadsignificant correlation, the determination coefficient, which was obtained by the partial least squares ofthe total nitrogen and organic matter, was 91.84% and 81.06%. Thought the experiments proved thatthe apparatus can basic meets for soil component content detection requirements in agriculturalproduction.