H21. Three Grades of Post-drop Screen Damage Classification
- Grade1: Only outer glass crack, intact display → single copper foil digitizer replacement;
- Grade2: Crack+local screen dark spot/line → full LCD+digitizer assembly swap;
- Grade3: Frame bending+internal component dislocation → calibrate middle frame before screen installation.
H22. Copper Foil Digitizer Core Identification Feature
Premium copper foil touch glass has additional conductive copper foil attached on flex root to shield electromagnetic interference, effectively lowering spontaneous ghost touch under unstable power environment, standard non-copper version lacks this design.
H23. Air4/Air5 Repair Differentiation Point
Air5(A2588) touch connector pin definition differs slightly from Air4(A2316), cross-model fitting leads to intermittent touch lag even with same outline digitizer.
