On the 3D-printer printed contact lenses with integrated OLED-display

A group of engineers from Princeton University as an experiment produced a contact lens with an OLED display on a 3D printer. The researchers demonstrated their 3D printing technology, which allows them to combine and print five different types of materials on curved surfaces: radiating semiconductor nanoparticles, elastomers, organic polymers, metallic conductors and light-curing materials.

The display operates on the principle of QD-LED (LEDs from quantum dots). Display points are obtained by multi-layer printing. Such a sandwich consists of a radiating layer (cadmium selenide nanoparticles, which are quantum dots) located between two layers, one of which emits electrons, and the other accepts. Electrons passing through a layer of quantum dots make it emit photons, and with a strictly defined wavelength. Another lower layer consists of a material that is UV curable - it allows you to glue this sandwich to the surface. The result is a very thin, flexible and almost transparent LED.


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Pixels in lenses can be done in one of two ways. They can be active, i.e. emit your own light, and create a picture in the eye directly. However, this approach is inconvenient in that it requires a relatively large amount of energy to work - and obtaining wireless energy depends, inter alia, on the size of the receiving antenna, which must be placed in the same lens. A different, passive approach is possible when the pixels change the light entering the eyes from ambient light, but technically it is more complex.

Although the technology is still in the experimental stage, the results are encouraging. It is difficult to imagine all the possibilities of its application. It is worth noting that the technology will fit not only for contact lenses - it will be the way and in the manufacture of "smart glasses".