Research Of The Refractive Index Measurement System Based On Displacement Sensor

The refractive index of the detection is improving the optical instrument quality on the premise, and it is the research of the important parameters of the imaging quality of the optical system. This paper designs a new refractive index measurement method and device, and it is based on the principle of optical imaging, using of optical flat panel imaging rule, finding the relationship between the measured index of refraction and system optical components of focusing amount, the relationship of the traditional refractive index and the angle is transformed into the relationship of the refractive index and the axial displacement, simple measuring method, non-contact measurement, and it is set to the integration of optical, machine, electric of high performance precision measuring instruments.Firstly this paper introduces the working principle of the refractive index measurement system, and designed the optical system by using Zemax. This system used three piece photographic objective lens system, the effective focal length of the system is45mm, the F number and the full field of view angle are4and8°respectively. The image sensor of the lens is1/3inch CCD, whose pixel size is6.35um×7.4um, according to the functional qualities of the apparatus, the system meets the requirement. Next, this paper details the precision machinery structure, and gives the design results, finally, analysis the error precision. The precision of the system can reach0.00885. And it can meet the equipment requirements.