Selecting the correct lens here is now made easy

(a) Single Vision

---Glass NO CHARGE

• Single Vision means either for distance or for reading. If you need both corrected in one pair of glasses then look at bifocals or varifocals.
• We will fit single vision glass lenses into the frame of your choice for distance or reading at no extra charge.
• Not recommended for children under the age of 15 years for safety purposes.
• Advantages and disadvantages of glass.

---Glass over +/-4.00DS

• If the spherical part [(3) above] shows a number over + 4.00 or less than - 4.00, then you have choose this option. We need to make the lens specially because it goes beyond the normal stock lenses

---Plastic CR39

• CR39 is the world-wide standard for plastic lenses. It's a high-grade material suitable for any prescription. Today 90% of all prescriptions are fitted in plastic.
• Advantages and disadvantages of plastic.

---Plastic over +/-4.00DS

• If the spherical part [(3) above] shows a number over + 4.00 or less than - 4.00, then you have choose this option. We need to make the lens specially because it goes beyond the normal stock lenses

---Photochromatic glass brown / grey

• These lenses have a special material (pigment) that makes them go dark in the sun so they act as prescription sunglasses.
• Select between brown or grey.
• I suggest to my patient to select the color that best matches the frame.
• In doors and at night, the lenses are almost completely clear.
• Advantages and disadvantages of glass.
• Advantages and disadvantages of Photochromatic lenses.

---Photochromatic transitions plastic

• Comes in a brown tint.
• Advantages and disadvantages of plastic.
• Advantages and disadvantages of Photochromatic lenses.

(b) Bifocals

• One lens corrects both distance and reading.
• With this type of lens you can see the shape of the reading segment (reading part of the lens).
• It's always best to select the same lens type that you've had before, unless otherwise advised by your eyecare professional.
• Let me describe the different types

---D-seg Flat Top 28mm

• The D-seg is the reading bit you can see on the above lens.
• It isn't stuck onto the lens, or separate in any way, but you can still see it.
• The standard size is 28mm.
• This type is the most popular of all the bifocals.
• Advantages and disadvantages of glass.
• Advantages and disadvantages of plastic.
• Advantages and disadvantages of Photochromatic lenses.

---Round-seg

• Not as popular as the D-seg.
• The round shape allows a "smoother" change from distance to near.
• Slightly less field of view than the D-seg.
• Available only in glass or plastic.
• Advantages and disadvantages of glass.
• Advantages and disadvantages of plastic.

---Plastic A-seg Ultex

• This segment is cut out from a large circle.It gives more reading area in the corners.
• Available in light-weight clear plastic only.
• This bifocal is rarely prescribed today.

---Executive

• This segment is suitable for certain occupations such as secretarial, architects and for certain trades e.g. plumbers, mechanics who are in awkward places.
• It gives them more room to look at the job up close.
• Available in glass, plastic and photochromatic grey only.
• Advantages and disadvantages of glass.
• Advantages and disadvantages of plastic.
• Advantages and disadvantages of Photochromatic lenses.

(c) Varifocals

• By far the most popular lens today (85%) for correcting distance and near vision.
• There is no line visible on the lens.
• The prescription changes gradually from distance to near, so there is no "jump" as with the bifocals.
• No one can tell you are wearing lenses for distance and near. Cosmetically they are far more attractive.

• The correction is nice and smooth and graduated.
• Available in glass, plastic, and photochromatic.
• Advantages and disadvantages of glass.
• Advantages and disadvantages of plastic.
• Advantages and disadvantages of Photochromatic lenses.