Digital Imaging Principle and Production Process III

3 Printing process

First of all, there must be a qualified inkjet printer and computer software that uses inkjet printers, including the user needs of the image drum speed of the image, the special drawing paper conveyor transfer speed, the temperature of the heating roller, various colors of the inkjet nozzle Ink sequence, speed, amount, evaporation rate after image printing, etc. The edited software is entered into the computer.

Before the inkjet printing, clean the inkjet printer and check that all preparations are in place.

The inkjet printer software program was used to start the inkjet printer program for inkjet printing. Beijing Yunyuan Digital Corporation has edited the complete set of inkjet printer software for users to choose and use according to the performance of different inkjet printers.

There are many types of inkjet printers, and inkjet printers produced by various production companies each have their own characteristics and patents, and their sizes vary, but generally include the various components shown in FIG. 3 .

3.1 inkjet printer head

The inkjet print heads on the inkjet printer have different designs, as shown in FIG. 4, FIG. 5, and FIG. Different inkjet printers have different inkjet print heads, and the nozzle aperture is about 4 μm. Generally speaking, according to the pixel, for example, Epson color stylus is 1440×1440 dpi, Lexmark 7000 is 1200×1200 dpi, and the number of pixels at the nozzle of the inkjet printer is more. The inkjet printer has a large density of nozzle openings, small nozzle apertures, small droplets of ink ejected, and fewer pixel points missing from the inkjet image. The resulting image is naturally fuller and more realistic.

The reason for the distorted image of a typical digital photographic print is that the pixel size of each pixel reflected by the ink droplets ejected and splashed on the carrier paper is a molecular level, and there is a certain distance between the particle point and the particle point, which is lost. Many pixels cause the contrast of the image to be large, distinct, and not rich and plump. The human eye looks uncomfortable and has a sense of distortion, which is why it cannot be compared with the beauty of traditional photographic images.

3.2 Printing Paper

If you use a general paper inkjet printer, spray a drop of ink onto the paper as shown in Figure 7. The ink dots are still etched in the periphery and penetrate into the deep layers of the paper, and the wet images of the ink dry slowly, affecting the printing speed. In order to prevent the ink from penetrating and accelerate the evaporation and drying speed of the ink droplets, it is generally necessary to apply a coating on the surface of the paper. The coating contains a polymer adhesive and titanium dioxide (TiO) or talc (SiO2). The thickness of the coating is matched with the ink. It helps to absorb some of the ink moisture (Figure 8, Figure 9), can promote rapid drying of the image, shorten the spray drawing time, reduce costs.

4 advantages and uses of digital photography images

4.1 The advantage of digital photography images is that they are produced in a variety of ways. The images are real, colorful, clear, and distinct.

4.2 Usage: Almost all of the traditional photographic imaging applications can be used interchangeably, and are widely used in CT, MR, DSA, ECT, US and other digital medical imaging inspection devices. It is also most suitable for large format images. Such as various kinds of policy propaganda images, product advertisements, light box patterns, etc.

Its only deficiency is that the images reproduced with it are not as vivid as the images printed with traditional camera reliance materials, the colors are beautiful, the layers are full, and the contrasts are soft.

5 Conclusion

From the advantages and applications of the above traditional photographic images and digital photographic images, it can be seen that for the current level of quality of digital photographic images, it cannot yet completely replace the application of traditional photographic images. People will take advantage of their respective strengths and avoid them. They will also coexist for a period of time. (Author: Tang Keguang)