Deuteranomaly is a condition in which the photoreceptor responsible for detecting green light responds to light associated with redder colours and predominantly affects males. It is also the most common form of colour blindness. This means that simple tasks like discerning if a banana is ripe or not becomes virtually impossible.
The image on the left has been unaltered and is what people without Deuteranomaly see, the image in the middle is what the world looks like to those who suffer from Deuteranomaly, the image on the right is what the world looks like when someone with Deuteranomaly is wearing the contact lens.
To remedy this problem, researchers from Tel Aviv University in Israel, developed a contact lens that makes use of ultra-thin optical devices known as metasurfaces which are capable of correcting deuteranomaly. Metasurfaces are artificially fabricated thin films designed to work with specific optical properties.
“We developed a technique to transfer metasurfaces from their initial flat substrate to other surfaces such as contact lenses,” said Sharon Karepov, a member of the research team that worked on the contact lenses.
“This new fabrication process opens the door for embedding metasurfaces into other non-flat substrates as well.”
“Our contact lenses use metasurfaces based on nano-metric size gold ellipses to create a customized, compact and durable way to address these deficiencies,” said Karepov.
To ensure that the contract lens would always provide accurate results, the team of researchers tested the optical response of the metasurface after every step of the new fabrication procedure. Their tests showed that the metasurface’s light manipulation properties did not change after transfer to the curved surface, indicating that the process was indeed successful.
Finally, researchers used a variety of colour perception simulations to quantify the deuteranomaly colour perception before and after introducing the optical element, resulting in an improvement of colour perception up to a factor of 10.
The contact lens still has to go through clinical testing before it can be marketed to the public, but researchers believe that manufacturers could potentially embed the metasurface during the moulding stage of contact lens fabrication or thermally fuse them to a rigid contact lens.