Because of the index change between water and air, dive masks with flat interfaces magnify by a factor of 1.34X, and the field of view (FOV) in water is restricted to about 60 degrees. In addition, the image suffers significant amounts of lateral color and distortion. For technical diving applications (e.g., underwater welding), these attributes reduce situational awareness, lead to poor hand-eye coordination and are highly undesirable. This paper describes the design issues and design solution of a unity magnification dive mask covering a full FOV of 140 degrees.
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