Eyes keeper / Contact lens

Nowadays many people who wears contact lenses too long is increasing. The users usually ignore its existence easily ,and forget to remove the contact lenses within the normal time period.It will cause the lack of oxygen in the eyes,and will gradually endanger the health of eyes or even lead to blindness.The design is through special detecting ink that can change colors depending on the amount of oxygen containing in the contact lenses.When there is insufficient amount of oxygen in the contact lenses,it will change colors to notice users.It will not only achieve the purpose of reminding the user to replace the contact lenses and avoid damages.