GLOSSARY

A nylon-based plastic that’s more durable than standard plastic, retaining its shape and colour for longer.

The amount of curvature at the front of the lens: the higher the base curve, the greater the curvature.

This type of material is poor at conducting electricity, so safety glasses labelled di-electric contain no metal parts.

This is an innovative method for manufacturing our RX prescription safety eyewear lenses, resulting in an optically-ideal base curve across all viewing zones.

These form part of the wave spectrum: travelling energy composed of electric and magnetic fields.

The standard type of lens used in safety glasses, they’re up to ten times more impact resistant than plastic lenses, as well as thinner and lighter. In its original state, polycarbonate is a thermoplastic that’s formed into a shape using injection moulding before cooling.

A type of lens coating that offers an intense colour and mirror effect.

Originating from an abbreviation of the Latin verb 'recipe', RX means prescription.

A coating that’s applied to many Riley eyewear products, making the lenses more resistant to scratches and misting. The coating meets the 'K' (anti-scratch) and 'N' (anti-mist) standards of EN 166.

Lenses coated with TECTON 400 stop harmful UV rays from passing through our eyewear. This high-performance coating also contains anti-misting, anti-scratch and moisture-repellent properties, applied to both sides of the lens.

An acronym for thermoplastic elastomer, this flexible and pliable material is often an evolutionary replacement for traditional rubbers.

Short for 'Columbia Resin 39' – the 39th formula of a thermosetting plastic developed by the Columbia Resins project in 1940 – CR-39 is a plastic polymer that’s used to make eyeglass lenses and a registered trademark of PPG Industries Ohio, Inc.

UV stands for ultraviolet – a type of electromagnetic radiation that reaches the Earth from the Sun.

It’s invisible to the naked eye and comprises wavelengths classified as UVA and UVB – both contribute to eye damage and cancers.

Ultraviolet A rays account for up to 95% of the UV radiation reaching the Earth's surface. Although they’re less intense than UVB, UVA rays are 30 to 50 times more prevalent. They’re present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass. UVA rays can also pass through the cornea and reach the lens and retina inside the eye.

Overexposure to UVA radiation is linked to the development of certain types of cataracts, and research suggests UVA rays may play a role in the development of macular degeneration.

The intensity of ultraviolet B rays varies by season, location and time of day. That said, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces like snow or ice. UVB rays are thought to cause pinguecula and pterygium – these growths on the eye's surface can become unsightly and cause corneal problems as well as distorted vision. In high short-term doses, UVB rays can also cause photokeratitis, a painful inflammation of the cornea.

The amount of light that can pass through a lens.

The size of light waves is measured in wavelengths, and calculated by determining the distance between corresponding points on consecutive waves – peak to peak or trough to trough. The human eye can only see wavelengths that are 400 to 700 billionths of a metre (nanometres) – commonly called the visible spectrum.