Study On Density Detection And Characteristic Characterization Of Spot Color

As one printing technology, the spot color printing is performed by adopting the prepared printing ink. Spot color halftone printing refers to one-time spot-color printing with colorful layers which can be realized by website just like four-color printing. With the high requirement of people for perfect and personalization and the improvement of modern anti-counterfeiting technology, the spot color will no longer meet the requirement of printing field; however, with the tendency of converting into the spot color halftone printing, the spot color halftone printing will be the norm. The real-time detection for print quality is performed to timely know the quality state of printing products, and to find and timely solve problems so that the printing quality is always in a state of stable, and controlled with arriving at the standard, and waste and defective products are reduced as possible. Some existing measuring instrument can be used for measuring the spot color, which is only performed roughly on the spot color field, and the obtained density value is not accurate, therefore the dot area coverage cannot be calculated, even the color halftone printing quality cannot be detected. In view of this, regarding the current density measurement technology asthe basic object to research, the thesis deeply research the spot color characterization method and the method for testing the density.Regarding the Pantone spot color as object to research, the thesis firstly develops a series of experiments with regard to the above problems, and takes the measured spot color density value as the main content to research, and proves the existence of the problem through the experiment, which lays a basis for solving the following problems. secondly, analyzes the spectral extraction method and density calculation method of the existing color in the process of measuring the density of the spot colour by the instrument spectrophotometer SpectroEye, and verifies the result; finally, the thesis performs the characterization on the spot color on the basis of the spectrum with special spot color characteristics extracted by SpectroEye, according to the characteristics of spot color, and improves the spectral product formula for density on the basis of the method for calculating the density of the spectral product, and verifies the calculation result. through analyzing and comparing the spot color data obtained by each measuring instrument, the thesis finds the problems of the measuring instruments in measuring the spot color, and has a deeper comprehension for the existing instruments for measuring density and spectrophotometer meter, which has a certain influence on reasonably using the instrument, and better services for Printing Corporation in detecting the spot color quality. The thesis verifies the density calculation method and the characterization spectrum extraction method by the spectrophotometer Spectro Eye, which can provide a certain theoretical guidance and technical support for the development and improvement of the relevant detection instrument with larger reference value.