Analysis of Art Screening Technology

Screening technology is the basic way to reproduce continuous tone images, and it is also an important technology that determines the quality of printed matter. In the field of printing, it has a history of more than 100 years. It has experienced glass screens, contact screens, electronic screening, and digital addition. Network and other development stages, and the formation of a rational screening, unreasonable screening, super cell structure screening and FM screening and other technologies. At present, AM screening and FM screening have been playing a leading role as the two mainstream screening technologies. With the advancement of science and technology, some special screening technologies have emerged. They have been used in some printing fields and have been used for different purposes. Prints.

Hybrid Screening Technology
As we all know, AM screening is to reconstruct the tone and gradation of an image by changing the dot size by fixing the dot spacing, which has obvious advantages for the restoration of intermediate tone. FM screening is to reconstruct the tone and gradation of an image by fixing the dot size and changing the dot spacing to restore the details of the image. Hybrid screening technology is a new type of screening technology developed by combining the advantages of AM screening and FM screening.

Hybrid screening is developed based on digital screening principle and computer control technology. The principle is to generate FM network points in the high-profile and dark tone parts of the image, while the intermediate tone part simulates the configuration of the AM network point, that is, maintain a certain network point. At the same time, the tone reproduction is achieved by changing the size of a single dot. Hybrid screening technology fully utilizes the advantages of FM screening, and maintains good printability of AM sites. Therefore, hybrid screening technology can achieve good image reproduction.

This network uses the amplitude modulation network as the skeleton and the FM network as the modification. The shape of the dot network is different, and the position is randomly distributed, which has both the characteristics of AM and FM network. The advantage of hybrid screening is that there is no problem with the dot angle and direction, and the low frequency component is reduced to reduce the graininess of the picture, and the high frequency component is reduced to improve the printing stability. Therefore, the printability of the hybrid outlets is better than that of the AM and FM outlets.

Art screening technology
The basic principle of art screening technology is to use various shapes of graphics or patterns instead of conventional dots to achieve the purpose of reproducing image tones and layers. The commonly used dot shapes of common screen technology are generally circular, elliptical, diamond or square, and the shape of the dot is controlled by the dot function. According to the Postscript screening principle, adjusting the mathematical model of the dot function can flexibly control the shape of the dot. This is the mathematical theory basis of the art screening technology.

Art screening is to describe the outline of the figure or pattern as a dot by certain algorithm, and then use the enlargement, reduction, or other non-linear transformation algorithm for the contour to make the contour curve correspond to the gray value of the image, and finally describe with the outline. The graphics or patterns complete the screening of the image. In the high-profile part of the image, the edge of the dot outline appears as a fish shape; the dark part uses a reversed dot, and the outline of the blank part shows an geese shape; and the middle tone part uses a fish shape and an geese shape to represent the ink portion and the blank portion respectively. Changing the mathematical model of the shape of the control network can change the shape of the fish and the goose into other shapes, such as various line patterns, to enrich the types of art screening.

Art screening technology is most suitable for large-scale outdoor posters and advertising paintings. What people see from a distance is the overall image effect of the screen. From the near place, they can also learn the special information contained in the outlets. In addition, anti-counterfeit printing is also suitable for artistic screening, and the microtext or icons (trademarks) are printed in the image as dot shapes. Since the dot contour algorithm is unique, it can play a certain anti-counterfeiting effect. Using microtext instead of dot-printed anti-counterfeit images, the small text hidden in the image can be clearly seen with the aid of a magnifying glass, thereby playing a role in authenticating the authenticity.