A type of Monocular Lens used as a Color Correction Lens since the late 1970's. There is no single producer of these lenses or holder of the trademark, so there are several companies that make and sell these lenses. Producers…


One of the two Sex Chromosomes in humans, and the home of the genes for the L-Opsin and the M-Opsin. Females have two X-Chromosomes, but Males only have one. Any Genes on the X-Chromosome are X-linked (or Sex-linked).


A cause of blue-yellow CVD, simply described as a yellowing of the vision. This constitutes a Tritan defect, albeit non-congenital. The biggest causes are drug toxicity (e.g. Digoxin, a heart medication), or age-related yellowing of the lens. Many believe (speculatively)…