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In this paper, a kind of photoacoustic detection system was established to measure the photoacoustic signals of glucose with different concentrations. In this system, the lateral model was used based on the optical parameters oscillator (OPO) pulsed laser and ultrasonic transducer. Meanwhile, the optimal absorption of 1064nm for the pulsed laser and the ultrasonic transducer with central frequency of 1MHz was used. The amplified time-resolved photoacoustic signals and photoacoustic peak-to-peak values of glucose aqueous solutions with different concentrations were obtained in the average of 128 times. In addition, the effect of detection distance on the photoacoustic detection of glucoses was experimentally investigated. The detection distance includes the vertical and the transverse distances between the photoacoustic source in the glucose aqueous solutions and the ultrasonic transducer were all considered. Moreover, the effect of detection distance on the prediction of glucose concentrations was also studied by using the linear fitting model. Experimental results show that for each glucose solution with different concentrations, the photoacoustic peak-to-peak value of glucose decreases in the form of exponent function with the increase of detection distance, and the peak point of glucose will shift toward right due to the increase of detection distance although the concentration isn’t changed. When the transverse distance between the photoacoustic source and the ultrasonic transducer increases, the photoacoustic peak-to-peak value of glucose linearly decreases. At the same time, the prediction accuracy of glucose concentration decreases with the increase of vertical and horizontal detection distances.
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