How to Read Your Eye Prescription

Posted on October 3, 2025 by Patrick Hercules

When a person goes to an eye doctor appointment, they may receive a prescription after their exam. This prescription is made up of an odd series of letters and numbers that are instructions for making your glasses. Here is what they mean:

In a typical prescription, there are two acronyms, one for each eye.

D.- is short for oculus dexter, which is your right eye
S.- is short for oculus sinister, which is your left eye

The sphere column is often abbreviated as SPH. This is the lens power needed to fix your vision. A minus sign (-) next to the number means nearsightedness. This means you see better up close and need distance correction. A plus sign (+) indicates that you are farsighted and can see better from far away and need your near vision corrected.

Lens power is measured in diopters, the unit of measurement used to calculate the focusing strength of a pair of glasses or contact lenses. If you see the sphere field written above as -9.00 D, this means there are 9 diopters of nearsightedness. The measuring system is an integer line, with zero in the middle, needing no correction. The further you get away from zero on either the minus or plus side, the stronger your prescription is.

The cylinder number is how much astigmatism you have, if any. This is when part of the cornea has a different curve. Normally, an eye is shaped like a basketball, rotated in any direction, with the curve staying the same. An eye with astigmatism is oval, or egg-shaped, or more like a football, with one curve being longer than the other. The CYL number corrects the different second curve.

The axis number tells you where the astigmatism is on the cornea. The axis is written in degrees between 1 and 180, indicating which way the astigmatism lines up.

The add column is where any additional lens power is written. For example, some people over the age of 40 may not want an extra pair of glasses for reading and may choose to wear bifocals instead. The lower half of the lens will give them their reading vision.

Additionally, there may be a field for prism on the right side. This is a special type of correction built into the lens for some people with double vision. This means they see two separate images of the same object. The prism fuses the two images together so they will only see one image.

The prescription for contact lenses is different because they sit directly on the eye. A contact lens prescription includes measurements specific to the size and brand of your contacts. Before you fill a prescription for contact lenses, you will need a contact lens fitting to see if they are right for you.

If you require an eye exam, you can schedule an appointment at Jamaica Hospital Medical Center’s Ophthalmology Center by calling (718) 206-5900.

All content of this newsletter is intended for general information purposes only and is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment. Please consult a medical professional before adopting any of the suggestions on this page. You must never disregard professional medical advice or delay seeking medical treatment based upon any content of this newsletter. PROMPTLY CONSULT YOUR PHYSICIAN OR CALL 911 IF YOU BELIEVE YOU HAVE A MEDICAL EMERGENCY.

August is Children’s Eye Health and Safety Month

Posted on August 8, 2018 by Andrew Rubin

Traditionally, the month of August is when children around the United States starting getting prepared to return to school. Often this will require them to visit their pediatricians for physical exams and vaccinations. One of the most important exams is an eye exam.

The American Optometric Association recommends that children get their first eye check-up when they are six months old. They should receive another check-up at the age of three, and again when they are either five or six. After the age of six, children should have their eyes examined every two years unless they wear contact lenses or glasses which require annual visits to an eye doctor. It is also recommended that your child visit an eye doctor if they exhibit signs and symptoms of a vision disorder. These include:

• Lack of interest in reading
• Not able to see things far away
• Constant tilting of the head
• Squinting when watching TV
• Frequent blinking and rubbing of the eyes
• Seeing double
• Holding a book close to the face
• An eye that wanders
• Covering one eye
• Inability to stay focused on an object

Eye health and eye health are very important. If you would like to schedule an appointment with an eye doctor at Jamaica Hospital, please call 718-206-5900.

Why Eye Exams Are Important For Your Overall Health- What Will Your Doctor Check For?

Posted on January 9, 2018 by Xavia Malcolm

Many people decide to see an eye doctor when they have experienced a change in their vision. However, it is advised that whether or not there has been a change in your sight, you should make checking your eyes a priority.

Comprehensive examinations can help doctors to not only detect existing and potential eye problems but can also provide signs of other health complications that may be developing in your body.

Routine exams can identify signs of eye problems that develop silently as well as serious illnesses such as high blood pressure, diabetes, high cholesterol and brain tumors.

How often you receive a complete eye exam depends on several factors including, age, family history, if you wear glasses or contacts and if you are at risk for developing eye disease. Most eye experts agree that you should have your eyes examined every one or two years.

During your visit, your doctor may perform the following tests or procedures to help determine the current status of your health:

Visual Acuity Tests- to measure the sharpness of your vision.
Cover Test- to check how well your eyes work together.
Slit Lamp Exam- to examine the structures of your eye. Several eye diseases and health conditions can be detected during a slit lamp exam such as diabetic retinopathy, corneal ulcers, macular degeneration and cataracts.
Glaucoma Test- to measure the pressure of your eyes and identify signs of glaucoma.
Pupil Dilation- to obtain a better view when looking inside your eyes. This allows the doctor to perform a thorough examination which is crucial for people who are at risk for developing eye disease.

Getting your eyes checked as recommended is highly important for your vision and overall health. Your doctor can identify and create a successful care plan for many diseases while in their early stages.

The Division of Ophthalmology at Jamaica Hospital Medical Center offers a full range of comprehensive medical, diagnostic, and surgical services. From annual eye examinations to surgical procedures, our board certified and fellowship trained ophthalmologists are dedicated to the prevention, diagnosis, and treatment of eye disorders and ophthalmic conditions. To schedule an exam, please call 718-206-5900.