Abbreviations & Terminology

Abbreviations & Terminology
  • ADD Additional Near Power Correction

    If your prescription is written with an ADD power this means that your doctor has indicated that you need a lens that will correct multiple fields of vision in a single lens. The RX will be written with your Distance RX and an ADD power will be written

  • AXIS Axis

    The AXIS is the angle at which the CYL is placed on a lens to correct an astigmatism. The Axis can range from 1 degree to 180 degrees.

  • BAL Balance Lens

    The RX may call for a BAL or Balanced lens in one of your eyes. If this is written in either eye it means that the prescription is the same for both eyes. It is typically used when a person has no sight in one eye so that both lenses are made to the same thickness for cosmetics

  • CYL Cylinder Power

    CYL power is written to correct an astigmatism. If your prescription is written with CYL power, then it will also have an AXIS too.

  • DV Distance Vision

    Your prescription is written so that you can see objects far away also known as Nearsighted Vision

  • NV Near Vision

    Your prescription is written so that you can see objects close also known as Farsighted Vision

  • OD Oculus Dexter

    The Latin term for RIGHT eye

  • OS Oculus Sinister

    The Latin term for LEFT eye

  • OU Oculus Uterque

    The Latin term for BOTH eyes

  • PL Plano

    Latin for flat and is only written in the SPH power portion of your prescription. This means that you have no visual correction needed for this eye.

  • RX Prescription

    Is your physical written prescription from your eye doctor. The eye doctor will write the expiration date on your RX. Typically, Prescription is valid for 1 to 2 years from the date it was written however it is up to your eye doctor to determine the expiration date.

  • SP Sphere Power

    This is the first power column listed on your prescription and can be used to correct either nearsighted or farsighted vision.