Most frames are suitable for most prescriptions, however...
If you are SHORT SIGHTED, (minus prescriptions) your lenses will be thicker at the edges than in the centre, especially on the temporal side (the outer edge). For high prescriptions you should choose a smaller frame style to reduce the edge thickness. Rimless styles do show of the edge thickness so consider wide rimmed frames that conceal this.
If you are LONG SIGHTED (plus prescriptions) your lenses will be thicker in the centre than at the edges. If you have a high prescription you should avoid larger frames. Smaller and rounder frame shapes will reduce the centre thickness and the overall weight of your glasses. Some thin or rimless styles may not be suitable.
Standard plastic lenses (CR39) - Ideal for lower prescriptions up to up to +/-3.00. These lenses cost £20 for our prescription glasses and come free with sunglasses. They are much lighter and safer than glass lenses and they tint well too.
Polycarbonate (1.59) - These lenses are thinner than CR39. They are about the same thickness as thin (1.6) lenses but they are slightly lighter making them an ideal choice to compliment a lightweight or titanium frame. Polycarbonate lenses are also very strong, they are about 12 times more impact resistant than standard plastic lenses and for this reason polycarbonate is used to make safety glasses. Polycarbonate should be the first choice for rimless or semi rimless (supra) glasses.
Thin Lenses (1.6) - These lenses are made of a higher refractive index (1.6) material than the standard (CR39) lenses which reduces the thickness of them. They are ideal for prescriptions above +/- 3.00. They will improve the aesthetics of your glasses and reduce the weight of them. 1.60 Lenses are up to 25% thinner and 20% lighter than standard lenses and are a good option when you are selecting a larger frame eye size e.g. 52 mm and above. They also have the added bonus of being tough.
Extra thin Lenses (1.67) - These are even thinner than the 1.6 lenses! They are ideal for medium to high strength prescriptions of around 5 diopters and are up to 33% thinner than a standard plastic lens They much flatter than a standard lens and will minimise the edge thickness which will improve the appearance of your glasses. 1.67 Index lenses are suitable for all frame types including rimless and semi-rimless designs.
Ultra Thin Lenses (1.74) - The ultimate in thin lenses. 1.74 lenses are suitable for higher prescriptions and are as much as 50% thinner than a standard plastic lens. They are the thinnest plastic lenses that are available and they are much flatter than a standard lens, which will minimise the edge thickness and optimize the appearance of your glasses.