US Patent 9146336 Synthetic resin lens

In a synthetic resin lens, a thermoplastic resin is caused to contain a blue pigment having the lowest value for light transmittance in 570-610 nm, and a pink pigment that, among blue light of 380-500 nm, has the highest value for light transmittance in 400-440 nm and the lowest value for light transmittance in 480-520 nm, resulting in a transparent achromatic lens having a lowest value for light transmittance in 570-610 nm. As a result, provided is a synthetic resin lens that, when used in sunglasses, corrective glasses, shields, or the like, has favorable contrast (visibility), few marked color changes when installed, and a natural color.