Purpose
Improving underwater vision is greatly desired by water sport enthusiasts and, with the newly designed underwater amphibious contact lenses, clear vision is provided. The project’s inspiration came by a simple and interesting adaptation in nature by the “four-eyed” fish Anableps anableps. The eyes of the fish contain 2 corrective regions: one for vision in air and the other below water. A human’s eye is optimally designed for in-air viewing with perfect vision, requiring a power of 43 diopters of accommodation. Each environment requires a different power range, permitting the viewer to observe images focused clearly on the retina.
Methods
The corrective crystalline lenses tested are asymmetric, unlike commonly used masks and goggles which limit the user’s field of view. The lenses are specifically prescribed for the wearer’s visual prescription to correct any defocus or astigmatism. They were tested in a number of environments and conditions for visual acuity and compared to goggles. Environments ranged from salt water to fresh water. The visual acuity was measured by a Snellen eye chart specific to the testing area. In addition to testing visual acuity at near and distant points, resolution limit, pattern detection and recognition, and color were tested.
Results
In Arizona at noon, the test results determined hyper-acuity reaching 20/16. The amphibious contact lenses had full number recognition to 20/25 and partial at 20/20. This concluded that the lenses are able to correct vision impairment and aberrations. Results were conclusive for pattern recognition for letters versus numbers read on Snellen charts. No matter the pattern on the chart the user was able to recgonize letters, shapes, and numbers to a visual acuity of 20/16 average.
Conclusions
This indicates that the wearer had improved visual acuity under water and above water with the contact lenses in the same conditions. In addition to increased visual acuity, there was immediate awareness of a full field of view. Varying pattern recognition chart types were concluded with positive visual acuity results. Overall, the lenses performed as expected. There should be decreased acuity in dark, murky conditions and a standard 20/16 in illuminated conditions. Future work involved in this research is to determine quantitative data for the field of view and use color patterns, for water absorbs red lambda and the intensity of red should decrease.