Back to Lens Thickness

1.60 High-Index Lenses

Starting from$49

1.60 index lenses are significantly thinner and lighter than CR-39. The most popular high-index material for moderate to high prescriptions.

1.60 High-Index Overview

1.60 index lenses are the most popular high-index lens choice. They produce lenses approximately 30% thinner than CR-39 for the same prescription — a noticeable improvement that makes a real cosmetic difference.

Thickness Comparison

For a -4.00 sphere prescription in a standard 50mm round frame:

  • CR-39 (1.50): edge thickness ~7.5mm
  • 1.60 high-index: edge thickness ~5.5mm — about 27% thinner

Best For

  • Prescriptions from ±3.00 to ±5.00 sphere
  • Patients who notice the thickness of CR-39 lenses
  • Larger frames where edge thickness is more visible
  • Astigmatism prescriptions with cylinder above ±1.50

Optical Quality

1.60 index lenses have excellent optical clarity, minimal chromatic aberration, and are available in all single vision, bifocal, and progressive designs.

Common Questions

How do I know which lens index I need?
As a general guide: up to ±2.50 — CR-39 works fine. ±2.50–±4.00 — consider 1.60. ±4.00–±6.00 — 1.67 recommended. Above ±6.00 — 1.74 is ideal.
Does higher index mean better optical quality?
Not necessarily. CR-39 has the lowest chromatic aberration of all plastic materials. Higher index materials have slightly higher chromatic aberration, though most wearers don't notice it.
Are high-index lenses more fragile?
High-index lenses have higher clarity but are slightly more brittle than polycarbonate. For impact-prone situations (sports, children), polycarbonate's toughness outweighs the thinness benefit.