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Understanding the Eye Chart

Eye charts of different variations have become a standard in vision screenings and eye exams. One of the most familiar charts associated with vision is the Snellen eye chart, designed by Dutch ophthalmologist Hermann Snellen in 1862 to measure visual acuity- how well you can see at various distances.

Although there are variations of the Snellen chart used today, a traditional Snellen chart has eleven lines of block letters. The first line has one very large letter, which is one of several letters, for example E, H, or N. The following rows have increasing numbers of letters that become smaller in size as you read from the top to the bottom of the chart. The letters used on the chart are C, D, E, F, L, N, O, P, T, and Z.

When taking a vision exam, one eye is covered and you are asked to read the letters of each row aloud beginning at the top of the chart. The smallest row that you can read correctly indicates the visual acuity in the eye being tested.

The chart is positioned at a distance of 20 feet in the United States or 6 meters in the rest of the world. The term 20/20 vision is used to indicate the clarity and sharpness of your vision measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet objects that can normally be seen at that distance. If you have 20/40 vision, it means that you need to be as close as 20 feet to see what a person with normal vision can see at 40 feet. The largest letter on an eye chart often represents an acuity of 20/200 which is associated with the term "legally blind."

You will be asked to read the letters one eye at a time. Some people can see well at a distance, but are unable to bring nearer objects into focus, while others can see items that are close, but cannot see them far away. By having you read the chart, your eye doctor is able to ascertain whether you have difficulty with distance vision and can determine which corrective lenses can be used to improve it. Near vision problems or other vision and eye health issues may not be detected with the Snellen eye chart alone, so a comprehensive eye exam is always recommended.

The next time you hop into the chair at your optometrists' office, you'll be able to understand why you have to read the letters on the chart in front of you and what the results mean for your vision.

SOUTH COAST OPTOMETRY UPDATE – JULY 1, 2020

COVID-19 has been and continues to be an ongoing trial for all of us. During this unforeseen time, we ask kindly for your understanding and compliance to the CDC guidelines. In order to decrease the chances of contraction, we are allowing only one parent to accompany their child during the examination. We appreciate your patience and understanding.

We also want to inform you of the new additional symptoms of COVID-19 that have been added to the previous symptoms as potential indicators of having COVID-19:

New symptoms:             Congestion/runny nose
                                           Nausea
                                           Diarrhea

Previous symptoms:       Headache
                                            Fever/chills
                                            Dry cough
                                            Shortness of breath
                                            Fatigue
                                            Sore throat
                                            Muscle/body aches
                                            New loss of taste or smell

Please be aware that a person does not have to have all of these symptoms but anyone or multiple symptoms can be an indicator of having COVID-19. If you or any family members are experiencing any of the above symptoms, we kindly ask that you reschedule your appointment and contact yourprimary care provider. It is best to reschedule your appointment with us after being symptom-free for14 days.

We at South Coast Optometry truly appreciate each and every one of you as a person and value your trust in us to take care of your most precious eyes. As always, we will continue to closely monitor the COVID-19 situation and communicate any and all changes through our website,
www.SouthCoastOptometry.com. Again, we truly appreciate your understanding and support during this unprecedented time and look forward to seeing everyone soon!

Sincerely,

Dr. Daniel E. Quon, O.D., and The Entire South Coast Optometry Team!!!

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Until further notice, we are only seeing essential care patients. Our hours are:
Monday: 10:00 AM to 7:00PM
Tuesday: Closed
Wednesday: 10:00 AM to 7:00 PM
Thursday: 9:00 AM to 6:00 PM
Friday: 10:00AM to 6:00 PM
Saturday: 9:00 AM to 5:00 PM

We now offer TeleHealth consultations, Call (714) 540-2020 to schedule a time
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