Final answer:
The screen for each component color in four-color printing is placed at different angles to prevent the moiré effect, which occurs when overlaid patterns interfere. This technique is critical in serigraphy and is similar to the color production in TVs.
Step-by-step explanation:
When printing with four colors, the screen for each component color is indeed placed at different angles to avoid a moiré effect. This technique is essential in processes such as serigraphy, or screen printing, where each color requires a separate stencil. The purpose of angling the screens differently is to prevent the interference patterns that can occur when similar patterns are overlaid at certain angles, resulting in the unwanted moiré pattern. The moiré effect can also be seen in other contexts, such as in butterfly wings or on credit cards, where thin film interference and diffraction create unique visual effects. In color printing, the primary colors used are usually cyan, magenta, and yellow, alongside black, to produce a wide spectrum of colors on paper. This method is similar to how color televisions produce colors. Careful alignment of screens or plates in printing ensures that images and text are clear and free of visual distortions.
When printing with four colors, each component color is placed at a different angle on the screen in order to avoid a moiré effect.
A moiré effect occurs when two repetitive patterns, such as the dots on a print and the dots on a screen, interact and create unwanted visual interference.
By placing the screen for each color at a different angle, the patterns of the dots are shifted, preventing them from aligning and causing a moiré effect.