Ritchie

Pupillary Distance (PD)

The distance between the centre of one pupil
to the centre of the other pupil is the PD.
Prescription glasses are made so that the distance
between the optical centres of the glasses' lenses,
is the same as your PD.

Prism UP/Down, In/Out:

Most Prescription Don't Have this/

Your prism helps your eyes to work together more comfortably by correcting their muscle balance.

Note:

If you have a prism correction, you will also have a base direction that will state one of the following - Up, Down, In or Out.
Down might be indicated by ‘DN’
You might have more than one Prism value per eye.
You will have a Base direction for each Prism correction.
The example below shows the prism required for distance.
You will use the H-Near and V-Near prism for reading as this might be different from your distance prism.

Works best for low prescriptions ranging from -3.00 to +3.00.

Works best for low prescriptions ranging from -2.00 to +2.00.

1.61

Up to 40% thinner than the basic 1.5 standard index lenses

Up to 60% thinner than the basic 1.5 standard index lenses

Most Impact Resistant Material, Recommended for Sports & Kids Eyewear. Polycarbonate Lenses have index value of 1.598, Up to 25% thinner than the standard 1.5 index lenses.

80% tint on top for distance, fades to a very light tint 20% tint at the bottom for reading.