Contact Lenses to Correct Color Blindness

By | March 9, 2020

Deuteranomaly is a color blindness that causes green light photoreceptors to react to redder light. Red objects seem greener for patients with the condition, but it has been known for a while that blocking some of the light in the red color range can improve proper color perception. There are glasses that do this, a pair of which we reviewed, but they’re slightly bulky and people with color blindness often find that it’s not worth it to wear them. Now researchers at Tel Aviv University in Israel have come up with a way to turn contact lenses into color correcting devices that improve color perception about ten fold.

The researchers were able to apply special metasurfaces, which are in the form of very thin films, onto conventional contact lenses. “Problems with distinguishing red from green interrupt simple daily routines such as deciding whether a banana is ripe,” said Sharon Karepov, one of the researchers, in a press release from The Optical Society. “Our contact lenses use metasurfaces based on nano-metric size gold ellipses to create a customized, compact and durable way to address these deficiencies.”

While this research demonstrated that it is possible to address deuteranomaly using novel contact lenses, the researchers believe the same approach can be used to provide a correction for other varieties of color blindness and even other types of vision disorders.

While metasurfaces that can manipulate light in interesting ways have existed for a few years, they have been typically flat and made independent of other devices. The Tel Aviv University team was able to come up with a technique to transfer these metasurfaces from flat to curved surfaces such as contact lenses.

Interestingly, even though they were no longer flat, the metasurfaces maintained the same light manipulation characteristics as in their flat state. The researchers applied a simulation of color perception across the new contact lenses outfitted with the metasurfaces and showed that the devices should be able to essentially restore proper color vision.

This is still in the lab stage and clinical trials will be necessary to make sure the technology works well in a real-world setting. Nevertheless, it seems that soon people with color blindness will be able to achieve proper vision by simply wearing a pair of contact lenses.

Picture: The top image shows the original scenario while the middle image is how the scene would look to a person with deuteranomaly. The image on the bottom represents the scene viewed with deuteranomaly and corrected with the new contact lenses.

Study in Optics Letters: Metasurface-based contact lenses for color vision deficiency

Via: The Optical Society


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