Difference on 2D, 2.5D, 3D tempered glass or 5D, 9D, 12D?

Difference on 2D, 2.5D, 3D tempered glass or 5D, 9D, 12D?

The screen protector is an accessory developing along with smart phone. The screen surface of early smart phones (to be precise, the protective glass above the screen panel) is flat. It is also a so-called “2D” screen (glass), the frame is parallel, or the screen is...
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