Research On The Key Technology Of Surface Topography Measurement Device Of Solar Panels

The surface texture of solar panels is one of the key factors affecting the conversion rate.Measuring the surface morphology of solar panels with optical measurement,comparing the relationship between the different surface texture parameters and the photoelectric conversion efficiency of solar panels,and determining the parameters which are closely related to the photoelectric conversion efficiency,which is used to guide the production of solar cells,will help to improve the efficiency of solar panels.In this paper,a set of surface topography measuring instrument based on vertical scanning white light interference is introduced.The shape measuring instrument scans the surface texture pixels with white light through the piezoelectric ceramic driving the flexible hinge mechanism to drive the Mirau interferometer moving vertically that changing the optical path difference between the reference beam and the measured beam.The CCD camera is used to collect the white light interference fringes at each vertical feed,and the collected information is transmitted to the computer by the image acquisition card.The movable grating moving with Mirau microscope synchronously has a relative motion with static grating caused intensity changing of the laser interference fringe.The four quadrant photovoltaic array detecting the intensity signal of laser interference fringe into electrical signal,then the electrical signal is regulated by the conditioning circuit and send into STM32 microcontroller for direction,subdivision and counting,the accurate measurement results of the vertical displacement of Mirau interference microscope are obtained and sent into the PC.The host computer superimposes collection patterns and then obtains the interference position distribution of the zero level white light interference fringes in the vertical direction,the optimal interference position of white light interference fringes is extracted by using the interference fringe extraction algorithm.The relative height of the zero optical path difference of each pixel is measured,the micro topography of the measured surface is obtained,then the parameters of microscopic morphology were evaluated furtherly.Finally,a set of standard samples are tested by using the measuring instrument,and theprecision of the vertical feed is verified.The accurate measurement results of the vertical displacement of Mirau interference microscope are obtained.The instrument can be used in the actual production of solar battery,guiding PV manufacturers to improve the production process and method,improve the photoelectric conversion efficiency,playing an important role in the development of photovoltaic industry,resource conservation and environmental protection.