Infrared contact lens have been specifically processed to detect invisible ink marks from marked cards invisible ink with glasses. The wavelength range of invisible light lies between 400nm-700nm. The wave band of invisible light can be seen with our naked eyes. The wave above 700nm can be called infrared poker cheating device, while the wave below 400nm can be described as ultraviolet. If the wavelength band of infrared is greater than 400nm, it’s impossible to see them with naked eyes. You will need special devices to detect this light.In poker cheating gambling, marked cards are becoming more popular. This card allows players to make more money gambling. Marked cards are printed with invisible ink, so that our naked eyes can’t see the luminous marks. You will need infrared contacts lenses. You can clearly see the marks with these lenses.