High-fidelity color printing technology began in the late 1990s and moved from the experts' laboratories into the printing companies' production workshops. This became a sign that the printing industry has begun striding into a new era of color quality. The ability of modern computers to perform high-speed arithmetic storage and software mass retrieval can help scientists further understand the characteristics of color, grasp the key technologies for copying colors, and correct the defects in the original printing theory and technology. In this effort, the experts studied the successful high-fidelity color separation technology and established a high-fidelity color printing package technology in cooperation with manufacturing companies to facilitate the practical application of printing companies. The application of high-fidelity color printing technology in printing companies today is as convenient as the application of conventional four-color printing technology, while at the same time it can greatly improve the quality of printing.

The progress of printing technology progress

From the manuscript analysis to the delivery of printed products to customers, the complexity of process parameters and the complexity of process parameters are difficult for outsiders to appreciate. However, in the face of customers with high quality requirements, the quality of printed matter is constantly criticized and blamed. Printed and copied scenes are always different from people's perceptions of actual scene observation in nature. Under the current conventional four-color printing process conditions, duplicating the bright and vivid colors of the paintings will become dull; the fluctuating light effects in the photographic works will become dull; the packaged printing products can be easily copied by other companies. Becoming an identity certificate for fake and shoddy goods... Companies and individuals pursuing print quality may think about such issues. When will the limitations of printing color be overcome? Can the quality of prints be completely new in their hands? The development of the printing industry is closely related to the progress of social science and technology. From the development of printing technology, it can be seen that in the middle of the fifteenth century, Johannes Gutenberg invented a printing method that reused metal movable type. In the eighteenth century, the development of optical technology and photosensitive materials helped the printed images show the effect of photographs, which enabled commercial propaganda and the dissemination of scientific knowledge into the wings of flying. In the nineteenth century, the development of color science not only created color photography, but also color separation and contact screen screening helped the printing industry realize full-color image reproduction. After entering the 20th century, the application of computer and laser technology enabled the printing industry to have its own color electronic color separation and halftone screening technologies. From then on, digital printing has taken place in the process of printing and copying the true colors of natural scenery. A key step in printing. At the end of the 20th century, high-fidelity color printing technology began to be applied in high-end printing enterprises, marking that printing technology has entered a new era. High-fidelity color printing technology is characterized by the fact that there are more than four primary color inks that participate in color separation, which enlarges the printing color gamut; the color separation algorithm ensures that the color components and the neutral gray component of the printing product replicate the closest to the visually perceived color characteristics. The product will present a new visual effect. Therefore, the printing industry has adopted a four-year color separation technology and has to retreat into low-end applications because of its obvious defects. In the course of the development of printing technology, the newest and oldest technologies shown in the new scene will be fortunate enough to be experienced by us. The pace of history will not stop. It is like exploring the birth and development of the universe, the earth, and humankind. Many problems still plagued us in the printing technology, and we must continue to study and solve it. Today's printing industry not only reflects the brilliance of modern scientific and technological achievements, but also shows the wisdom and pursuit of printers of all ages.

The characteristics of the new era of printing industry

Today, color scientists all over the world continue to provide many valuable methods for the perception, measurement, and reproduction of colors. This makes it possible for us to think new ways about printing technology and quality, seek new methods, and take a new height. The complexity of the process parameters of printing companies is mostly related to color images. The process basis for conventional color image printing and copying is four-color separation. There are two issues worth considering about this foundation. First, the printing of color images actually replicates the scene in the natural environment. The printing process cannot directly copy the real stereoscopic scene to the planar media. The photographing device projects the scene onto the photosensitive material or records it into the photoelectric conversion device and then passes it as a manuscript to the printing process. The ideal manuscript should faithfully represent the shape, color, and brightness characteristics of the actual scene.

In order to make the printed image closer to the observation effect of the actual scene, we should understand the color characteristics of the manuscript record and how it differs from the visual perception of the scene in the natural environment. This is especially important for ensuring the quality of high-end prints. For the difference description of the two and the analysis of their technical reasons, the author will write another article. Here, it is mainly pointed out that in the conventional four-color printing process, this is a problem that has been intentionally or unintentionally ignored. This has led to the current four-color printing process customarily obtaining CMYK data from the original scan, regardless of whether the separation model is reasonable or not, regardless of the difference between the scanned data and the visually perceived color characteristics. This makes the brightness characteristics of the printed image much different from the actual scene. It is avoidable to properly handle this difference. The oblique line in Fig. 1 is the brightness characteristic of the conventional four-color printing, and the upper arc-shaped curve formed by the blue dots is the Munsell lightness curve, which represents the brightness characteristics of the visual perception of the true scene color. Because the conventional four-color printing uses a different linearity from that of a real scene, the perceived perception of the brightness of the duplicated image is greatly distorted. Second, the four-color printing color space is much smaller than the light color space reflected by a real scene, destined to produce a considerable difference between the color characteristics of the printed image and the actual scene, in particular, the bright color saturation loss is serious. Four-color printing cannot be changed. The polygon in FIG. 2 represents the conventional four-color printing color gamut. The shark fin curve in the figure is the color spectrum of the natural spectrum that can be perceived by human vision. The area between it and the printed color gamut represents the color that cannot be represented correctly by four-color printing. Therefore, as well as the above-mentioned result of the image brightness characteristic copying distortion, the color of the four-color printing image is heavy and monotonous, lacking in layers, lack of brilliance, and lack of three-dimensionality.

Fortunately, after the unremitting experiments of experts, the above two issues have been solved in a unified way in high-fidelity color printing technology. Figure 3 is a high-fidelity seven-color printing color gamut. Compared with the four-color printing color gamut in Figure 2, the expansion of printing color gamut can be clearly seen. The high-fidelity color separation technology controls the neutral gray component of printed colors by visually perceiving the brightness of the colors, and expands the printed color space to map the hue and saturation of the perceived colors, so that the printed image effect is closer to the observation effect of the actual scene. Figure 4 is a schematic representation of the plate and printed image used for high-fidelity seven-color printing.

Since the mature high-fidelity separation model design tools have been developed, the basic color inks can be changed according to requirements, and new color separation models and neutral gray balance models can be quickly constructed to make them become technical solutions for printing companies or customers. From the above results, it can be said that high-fidelity color printing technology is a sign of a new era in the history of printing technology. This technology will promote the development and application of exquisite printing, personalized color printing, and color security printing. In this sense, high-fidelity color printing technology will also be a sign of the advancement of the printing industry's technological level.