Sphere

[Nick Eyeglasses]

SPH = SPHERE - The amount of long or short sightedness. This value specifies the optical power of a lens in diopters. It always has a plus (+) or a minus (-) sign in front or above it. The lens power for the distance correction will be minus while the correction for near distance and reading will be plus power. There will always be a value for sphere, even if it is just zero (written as 0.00, Plano or P).
As you can see in the sample chart, the patient's right eye needs a power of -3.25 and left eye needs a power of -3.50. If the doctor put down P or Plano in this field, you can just choose PLANO when ordering