Tech Talk

The Basics

1/ UV - Ultra Violet - Invisible light rays are considered harmful to the human eye and if not protected will cause cataract - Main source - The sun

2/ IR - Infra Red - Heat rays are also damaging to the unprotected human eye as it affects the cornea causing a drying effect - Main sources: the sun/mechanically generated such as gas welding

3/ Blue Light - This is the light that causes eyestrain and fatigue. Main sources - The sun and some artificial light such as neon

4/ Nm - Nanometre - A unit measure of light waves

5/ UV 380 Lenses - Blocks out 99.9 -100% of UV rays up to 380 nanometres - mainly used in clear lenses

6/ UV 400 Lenses - Block out 99.9 -100% of UV rays up to 400 nanometres - mainly used in tinted lenses

7/ Zero Power - Another way of saying there’s no lens magnification and that it’s distortion free

8/ Base Lens - Relates to lens curvature. A prefix number signifies the amount of curve on a lens. The bigger the number the bigger the curve. Most wrap around designs are normally between 8 - 10 base

9/ Medium Impact Approved (AS/NZS 1337.1) - When an eye protector is subjected to and passes a series of accredited test procedures where a 6.35mm diameter steel ball is projected at a velocity of 40m/sec

10/ Co-molded - The bonding of two materials during manufacturing stage (e.g Injection moulding)

11/ Photochromatic - The automatic darkening process that occurs when a photochromatic lens is exposed to UV sunlight

12/ Rx Ready - Prescription able

PC Lenses

Made from tough stuff called Polycarbonate (Plastic). It’s shatter proof, lightweight, optically correct and blocks out 99.9 - 100% of the sun’s rays (UVA - UVB) in all shades….even clear! All Scope PC lenses in clear, smoke, amber and copper are C-MaxTM coated (anti-fog/hard coat) as standard on both lens surfaces. All mirror lenses are hard coated.

Lens Category

Classification

Untinted and tinted spectacles/lenses are categorised by the amount of light allowed to pass through the lens. This is called the luminous transmittance. A lens with 18% transmittance allows 18% of visible light to pass through to the lens. Alternatively it restricts 72% of visible light passing through the lens.

Lens Category

Definitions

0

Very low sun glare reduction

1

Limited Sunglare reduction, NOT SUITABLE FOR DRIVING AT NIGHT

2

Medium sun glare reduction

3

High sun glare reduction

4

Special Purpose Very high sun glare reduction

Frames

The majority of our range consists of two main types of materials.

1) a. Polycarbonate - It’s strong, Iightweight and depending on the frame design can also be slightly adjusted for fit

b. Co-molded - A great combination of polycarbonate with mainly rubber compounds bonded together resulting in lightweight and very comfortable designs

2) Nylon - No big secret to this material - bend it, stretch it, twist it - it’s almost unbreakable. Depending on the level of humidity, nylon frames will also naturally absorb atmospheric moisture making them softer and more flexible

Lens Markings

As required by AS/NZS 1337.1, all approved products are to indicate relevant markings as shown.

Single lens models - one side

Dual lens models - both sides

Scope Lens Mark

The letter I Indicates Medium Impact Approved

The letter O indicates the lens can be used either indoors or out & mainly seen on clear & amber lenses. They will filter out UV but not glare.

The letter C indicates the product is approved for liquid splash.

The letter M indicates the product has been approved for Molten Metal/Hot Solids

The number indicates the lens shade approved for Gas Welding as per AS/NZS 1338

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