Anti spill cup / articles for daily use

In conformity with the gravity induction theory, before your hand touches the cup, the special lid which is like the shutter of the camera will close. However, when you hold the cup in the hand, the lid will open automatically. *only when your hand hold the cup, the lid will open,otherwise it will be closed.
* this cup can be applied for dangerous liquid, for instance, sulfuric acid etc. It can prevent the liquid from spilling out.
Also, it can be used for drinking water like the ordinary cup.