Infrared contact lenses are specially treated to detect invisible ink marks on marked cards. The wavelength band of invisible light is between 400nm and 700nm. We can see things in this band with the naked eye. Those with a wavelength of more than 700nm are called infrared rays, and those with wavelengths below 400nm are called ultraviolet rays. Things in the infrared or ultraviolet bands are invisible to our naked eyes. We have to use some device to detect special light.
Marked cards are becoming more and more popular in cheating poker games. With the help of these cards, players can win more easily in gambling. But marked cards are treated with invisible ink, so our naked eyes cannot see the luminous markings on the card. We need to wear infrared contact lenses. Through these lenses, you can see the markings clearly.
Visually, invisible ink contact lenses are no different from regular contact lenses. Premium contact lenses are low in water, so these contact lenses are less likely to dry out your eyes. Even if you wear contact lenses for the first time, you will not feel any abnormality in your eyes.