Research On Construction And Application Of Printing Dot Based On 3-D Model

As the basic unit in the image, the dot plays an important role in the printing quality control and evaluation. The dot morphology situation in the printing or proof process has a direct influence on ink transfer and image reproduction and different dot will lead to different color and tones. Generally, the investigation for the influence of micro dot morphology on image quality all belong to macro evaluation such as Visual evaluation and the chroma ?density?dot gain and other parameter measurement. If the research can base on microcosmic point of view to analyze the image reproduction, the printing quality problems will be solved fundamentally.This paper takes the 3-D dot morphology as the research object, puts forward the application of photomicrometrology to construct the 3-D printing dot model(D-M) by Shaping from Shading(SFS) to restore the micro dot morphology accurately and then the influence of3-D forms of dot on printing quality will be analyzed subjectively. Using it as a base, Digital Elevation Model(DEM) Analysis System is utilized to describe micro morphology parameters.Finally, the paper conducts a research on surface properties of prints and printing quality evaluation system. The main research content is as follows:(1)Extraction and characterization of micro dot propertiesIn order to solve the dot surface height for 3-D model building, photomicrometrology is proposed to extract 2-D dot information accurately. And then the micro precise sphere as the reference is used for the accuracy evaluation of the algorithm so as to verify the applicability of the model in the aspect of micro restoration. What's more, an improved morphology restoration algorithm is applied to raise the algorithm accuracy. The improved algorithm estimates the illumination parameters from 8 neighborhoods to get the deviation angle and dip angle so that it will have a better applicability in the micro field.(2) Analysis and quantization of micro dot propertiesDigital Elevation Model(DEM) Analysis System here is used for surface measurement and quantitative calculation of dot morphology in the surface of the prints from the micro level to screen out high-precision parameters that are the most applicable to feature description of the surface of the prints. On the basis of the parameters from FM and AM dots, this chapter will research the different influence on the printing quality and combines scanning electron microscopy(SEM) to analyze and evaluate of dot morphology characteristics.(3) Prediction and evaluation of printing qualityBased on accurate models(D-M) of AM and FM dot parameters, the evaluation model(M) is created to describe micro printing quality. The correlation function(Ni) between microparameters and each single macro quality index is built by SPSS method. In addition, the evaluation model(Y) is constructed to predict comprehensive printing quality from micro level according to the relevance of M and Ni. At last, the system for predicting quality, comprised of M, Ni, Y, is established through detecting dots the surface of prints.The research conducts the visible representation and quantitative analysis of the micro dot morphology and establishes the comprehensive quality evaluation model of printing image,which has not only good visual observation effect but evidently increases the accuracy of characterizing and measuring micro indexes. It realizes the transformation from 2-D to 3-D and from macro measurement to micro characterization in the field of printing quality measurement.This new idea and method will bring some positive influence on research methods and research results of micro dot properties, which provides the possibility for printing quality control from the source and offers a new micro measurement method for printing quality control and evaluation.