1.To show the color shades by ink hole depth. The feature of this gravure is the different depth.The thickness bigger,the tableau darker.The thickness smaller, the tableau brighter. Just like corrosion and laser engraving gravure gravure.
2.To show the color shades by ink hole area size.The feature of this gravure is the same depth , only the size is different. The area size bigger, the tableau darker. The area size smaller, the tableau brighter. This type called halftone gravure also. At present only used in small unit.
3.To show the color shades of shades by ink hole area size and depth. Then the ink hole has big area size and depth, the tableau darker. Then the ink hole has small area size and depth, the tableau brighter.Just like electronic engraving type.
