From company: EnChroma is based on a unique approach to color blindness correction: restoration of the spectral separation between cones using a narrow-band notch filter. The effect works for people with forms of anomalous trichromacy, which are the majority of cases (about 80%). The notch filter, when designed correctly, can be provided without inducing a color tint to the lens–it appears to look like an ordinary sunglass lens. Unlike conventional color-tinted lenses which distort colors–emphasizing one color at the expense of others, EnChroma lenses amplify the perception of all three primary colors simultaneously (red, green and blue). The result is a “boost” to the chromatic saturation (purity or vividness) of colors.