OD – RIGHT EYE information OS – LEFT EYE information OU – BOTH EYES information SPH – SPHERE This indicates the strength of the lens required to correct your focus. NEARSIGHTED – there is a (-) minus sign next to your number – i.e myopia (difficulty focusing on distant objects). FARSIGHTED – there is a (+) plus sign next to your number – i.e hyperopic (difficulty focusing on close objects). CYL – CYLINDER Identifies how much lens power is in your prescription, as well as for astigmatism (difficulty focusing at certain angles). It always comes after sphere power in a prescription. NEARSIGHTED ASTIGMATISM – there is a (-) minus sign next to the number. FARSIGHTED ASTIGMATISM – there is a (+) plus sign next to the number. IF YOU HAVE A CYLINDER, YOU MUST ALWAYS HAVE AN AXIS. AXIS The AXIS specifies where the astigmatism is on your eyes. IT IS ONLY PRESENT IF THERE IS VALUE IN YOUR CYL BOX – IF YOU HAVE A CYL, YOU HAVE AN AXIS. The measurement is in DEGREES and the value range is between 0 and 180. ADD – ADDITIONAL CORRECTION REQUIRED FOR READING Used to make reading, bifocal or varifocal glasses. Indicates how much power is required ‘on top’ of the prescription for near or intermediate glasses. PRISM – REQUIRED TO CORRECT A LAZY EYE This is included with a prescription to correct special conditions or eye disorders (like squints) that requires the focused image to move positions