Trivex is a lens material made of a urethane-based pre-polymer.
Safety Glasses with Trivex Lenses
Because it is lighter than polycarbonate and yet exhibits both exceptional strength and superior optical clarity, it has become a common lens material for use in safety glasses.
Trivex was originally intended for use in military eyewear. It was so successful that PPG Industries, the company that developed it, introduced Trivex to the optical industry as a seamless alternative to glass, plastic, or polycarbonate lenses. PPG describes Trivex as “The complete package of optical quality, lightweight comfort, strength and protection – the critical performance characteristics called for in everyday living.”
The visual clarity of Trivex compares favorably to polycarbonate, its nearest rival in terms of overall performance. Abbe Value is the measure of chromatic aberration (or lens distortion), and the lower the Abbe Value, the more aberration is present in the lens; therefore, a higher Abbe Value number is desirable. The Abbe Value of polycarbonate is 30. Trivex boasts an Abbe Value of between 43-45.
In the weight category – another very important aspect of eyewear – Trivex beats all comers. It is lighter than high index plastic lenses, standard plastic (CR-39), polycarbonate, and all glass lenses. Lighter weight means less slippage and more comfort for everyday use. Lighter lenses can be especially beneficial when used in safety glasses, where long-term usage is often a factor and less weight means increased levels of comfort and fit. Lighter lenses also result in less safety glass re-adjustment, leaving your hands free to engage in work activities.
Trivex is clearer and lighter than polycarbonate, yet it is also nearly as durable, which makes it a great choice for safety eyewear. The high impact resistance and robustness of Trivex give it a structural rigidity that make lenses made from the material highly resistance to cracking and breakage. Some other stats about Trivex:
- Refractive Index is 1.532
- Abbe Value of between 43-45
- Density of 1.1 g/cm³ makes it the lightest corrective lens material in common use
- Ultraviolet Light Cutoff of 380nm
- Blocks 100% of the sun’s harmful ultraviolet rays
- Compatible with most applied external coatings, such as an anti-reflective or scratch-resistant coating
- Compatible with digitally-surfaced progressive and single vision lens designs
- Compatible with polarized or photochromic (transition) lenses
- Unlike polycarbonate, Trivex can easily be tinted