Researchers at Khalifa University in the UAE have created a prototype contact lens, the structure of which allows the most efficient way to filter red light today. Its second advantage is the absence of toxic dyes, which are used in old models of corrective lenses and pose a health hazard. However, the device has not yet passed clinical trials and is not yet ready for practical use.
The Arabian scientists got the idea of these lenses from the legend of “cranberry glass” – an ancient miracle of glassmakers who added gold particles to molten raw materials to give it a mysterious reddish hue. Scientists have prepared fully biocompatible gold nanoparticles with light scattering effects, which are immersed in a hydrogel polymer. The particles behaved like tiny mirrors, reflecting light at specific wavelengths.
In the course of the experiments, the optimal size of these particles was selected – 40 nanometers. With such parameters, their sticking together is excluded, and in addition, such small objects cannot filter out too much light – their capabilities do not go beyond the established wavelength range. This is 520-580 nanometers, where green and red shades overlap each other, and filtering allows you to minimize this effect and significantly improve color recognition by people suffering from color blindness.