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Determination of Reading Glasses Strength

1. To determine your 'ready-to-wear' reading lenses strength, you can download a PDF Reading Test Chart at Downloads. Instructions for using the reading test chart are provided on the download.

2. Obtain your reading strength from your Optical Prescription. A number of examples of the different prescription formats are shown below.




Prescription 1
SphCylAxisSphCylAxis
R-1.25-1.0070Distance-0.75-1.2525L
+1.25-1.0070Near+1.75-1.2525

Prescription 1 shows the single vision reading glasses requirement in the 'Near' row.

Right eye:+1.25
Left eye: +1.75



Prescription 2
SphCylAxisSphCylAxis
R-1.25-1.0070Distance-0.75-1.2525L
+2.50 AddNear+2.50 Add

Prescription 2 is for bifocal or varifocal glasses, the reading strengths are:

Right eye:Right Sphere+Right Near Add=-1.25 +2.50 = +1.25
Left eye: Left Sphere +Left Near Add =-0.75 +2.50 = +1.75



Prescription 3
SphCylAxisNear Add
R-1.25-1.0070+2.50
L-0.75-1.2525+2.50

Prescription 3 is a reformatted version of Prescription 2 and the reading strengths are calculated in the same way.

Right eye:Right Sphere+Right Near Add=-1.25 +2.50 = +1.25
Left eye: Left Sphere +Left Near Add =-0.75 +2.50 = +1.75



'Prescription reading glasses' include both Sphere and Cylinder-Axis correction components in the lenses, shown below.

SphCylAxis
Right eye:+1.25-1.0070
Left eye:+1.75-1.2525