Genuine contacts are composed of three layers, the middle is the color, the upper and lower sandwiched between the middle of the color piece, generally called “hamburger form”. Inferior pupil is composed of two layers, this pupil is directly on the inside of the two lenses coated with pigment, and then baked made, it is very easy to “lose color”, which is very harmful to the eyes. Color contact lenses are commonly known as contacts. Genuine contacts are composed of three layers, the middle is the color, the upper and lower sandwiched between the middle of the color piece, generally called “hamburger form”. Nowadays, women who love beauty often do not go to regular stores to buy contacts for convenience, and the contacts you may buy are made up of two layers. This kind of contacts is directly on the inside of the two lenses coated with pigment, and then baked made, it is easy to “lose color”, which is very harmful to the eyes, so be careful to buy. When choosing colored contact lenses, you should pay attention to the following problems: First, before wearing colored contact lenses, you need to undergo a strict eye examination, and buy colored contact lenses from a distribution unit that has an examination room, a fitting room, an optometry room, etc. and professional equipment, and wear them correctly under the guidance of a professional physician or an optometrist. Color contact lenses should be replaced and reviewed regularly, and should be worn and cared for strictly according to the instruction manual and the use method instructed by the physician or optometrist. Third, wearing color contact lenses, pay attention to hygiene, to avoid infection caused by unhygienic, in principle, should be removed every day in accordance with the provisions of the cleaning and disinfection process, the best not to wear when you sleep, so that the cornea to get the natural respiration, reduce complications. Fourth, the lens case is easy to breed bacteria and fungi, need to be often rinsed with boiling water, in stop wearing contact lenses, should be strictly cleaning and disinfecting lenses, and soaked in care solution, also need to change the care solution once a week. After wearing once found eye pain, photophobia, tearing, congestion, etc. should be immediately removed from the lens to stop wearing, timely to the hospital.