The screen has white, yellow, amber, red, and the like.

The color of the screen has a great influence on the quality of the plate making.

Colored screens, such as yellow, red, and amber screens, can prevent light from diffusing when printed, while white screens can cause significant diffusion.

This is because the photosensitive material has a large absorption peak in the ultraviolet region, and since the white screen reflects white light when the light source is irradiated, it has an influence on the photosensitive material.

The illuminating light reaches the emulsion coating through the transparent portion of the positive film, and the reflection, refraction, reflection and diffuse reflection phenomenon occur when the illuminating light contacts the white screen, so that the printing plate appears to be floating phenomenon, that is, vignette.

If a colored screen is used, this phenomenon is prevented because the colored screen can absorb a part of the illumination light, thereby reducing the reflection intensity of the illumination light, and the colored screen reflects the color light, which is inactive light, so the sensory selection The material does not have an effect, especially when the fine print is printed, the color of the screen is especially important.