Design And Implementation For Color Printing Image Alignment Of Visual Monitoring System

With the improvement of printing technology,the modern printing machine has been on the target of high quality,speed,automatic development direction.The progress of the image processing technology drew people much more attention to machine vision technology,which is expected to be successful applications in the automatic printing machine.The accuracy of overprint is one of the essential factors for the qualities of modern color printing technology.Printer used to detecting the qualities of overprint with their naked eyes in the traditional way.The technology over print could be attained in a way of higher qualities,higher efficient and more accurate adjustments with application of the image processing technology and machine vision technology.The paper firstly preview color printing production completely,especially on the issues of overprint technology and overprint quality direction.Combined with the realistic requirements of pressing enterprises,it thoroughly studied the image processing technology and the machine vision technology and further designed and completed machine vision and recognition of color printing image alignment technologies.The system can automatically monitor the qualities of four-color printing overprint,with which the alignment mark is imaged by CCD camera.The technology would makes it possible of identifying the overprint qualities,sending signal when the misregister and deviation adjusting signal occure.It can make the printing machine automatically adjust the plate location and correct the standard deviation.First of all,according to the requirements and difficulties of the system design,the paper developed an overall scheme on the difficulties off the system design.It includes the selection of hardwares of the system and their main parameters,software function module,etc.Secondly it designed algorithms for the sign the alignment mark image processing.It contains the standard of alignment mark image production,preprocessing and extraction of alignment mark image,processing and extraction of alignment mark image,deviation calculation and deviation correction of alignment marks,alarm function.Besides,the paper attempted to completed an alignment mark images acquisition technology,image processing technology,alignment deviation adjustment of PLC control technology,and data management technology.In the windows operating system environment,the project programmed with C++,combined with HDevelop in Halcon and completed the results.Also,the default function of the system is implemented.Finally,the accuracy of the system,the detection precision and real time,have been tested in this thesis,respectively.The results show that the production requirements of the alignment quality monitoring and deviation adjusting can be reached by this design.