Research And Implementation Of Absorbance Optical Detection System Considering Wetting Effect

Optical detection is a qualitative and quantitative analysis technology that uses optical methods to measure optical or non-optical quantities.Absorbance optical detection technology is used to measure trace metal elements in chemical experimental research.The determination of protein,carbohydrate,enzyme and nucleic acid in biomedical analysis and food safety analysis are widely used.However,the existing absorbance optical detection technology is not only affected by endogenous interference factors such as drift noise and voltage,but also affected by the measurement of bending liquid surface due to wetting effect,thus affecting the measurement accuracy.In order to improve the accuracy of absorbance optical detection technology in rapid quantitative determination,this paper studies and analyzes the influence of bending liquid on detection accuracy,and redesign the detection light path of absorbance detection system considering its influence.Finally,the design of this paper is verified by setting up a test platform.Firstly,the surface characteristics of the curved liquid surface are studied from the formation mechanism of the curved liquid surface,and the basic equation Yong-Laplace Equation of the curved liquid surface is verified experimentally by optical transmission method.Then,based on the theoretical basis of absorbance optical detection and the formation mechanism of bending liquid surface,the influence of bending liquid surface under wetting effect on absorbance detection is studied,and its influence is described and analyzed.Secondly,according to the previous theoretical analysis,starting from the establishment condition of absorbance detection principle,the detection light path of the detection system is redesigned by applying geometric optics and the energy distribution law of light in the process of reflection and refraction.The designed detection light path is modeled in the sequence mode of ZEMAX optical simulation software,and the energy loss of detection light through curved liquid surface is optimized as an evaluation function.The optimized light path is simulated in the non-sequence mode,and its detection light path is evaluated.Thirdly,according to the detection light path designed above and the actual detection requirements,the absorbance optical detection system is designed as a whole,mainly including the mechanical structure,hardware circuit and control system design of the detection light path.Wherein the mechanical structure comprises an absorbance detection light path structure and a transmission system structure;Hardware includes motion control circuit,power management circuit,communication circuit design,LED light source and silicon photocell circuit design,etc.The software program design mainly includes LED light source and silicon photocell driver design,serial communication design,etc.Finally,according to the absorbance detection system designed above,an experimental platform is built,and the detection optical path system designed in this paper is further verified from experiments and industry standards in multiple dimensions.The results show that the detection optical path system designed in this paper can perform quantitative determination of detection substances faster and more accurately,and has the advantages of good stability and strong anti-interference.