How to choose the lenses thickness? What is the relationship between lenses thickness and the refractive index? Nancy November 27, 2019 14:58 Updated Follow The higher the refractive index, the thinner the lens, the more the light transmittance. Related articles Frame Size and Strong Rx How to choose frames? What're the difference between Tint lens, Photochromic lens and Polarized lens? Difference between Spherical Lens and Aspherical Lens What is the difference between single-vision and progressive lenses? Comments 0 comments Please sign in to leave a comment.