Development of a New Method for Turbidity Measurement Using Two NIR Digital Cameras

Abstract

This paper proposes a new method of using two NIR digital cameras to measure water turbidity accurately and quickly. A measuring device based on an NIR camera and image processing software is designed. Two NIR cameras collect scattered and transmitted images when the NIR light is passing through the turbid solution. The average RGB values of 400 pixels in the central region of the image are obtained and converted into CIE Lab color space values. The water turbidity was measured by the functional relationship between turbidity and the corresponding color components (R, G, B, L, a, b, and grayscale). The results of comparison with a commercial turbidimeter show that this method has a high accuracy for the determination of standard solution with wider linear range and is consistent with the turbidimeter results for the measurement of real samples, which verifies the feasibility of this method.

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