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Screening tool · 1 min

Astigmatism Sunburst Self-Test

Sunburst chart to check if some line directions look sharper than others.

Reviewed by Dr. Roxanna Gangi, Optometrist

What this test measures

Whether light focuses evenly on your retina. With astigmatism, the cornea is shaped more like a rugby ball than a football, so certain line directions appear sharper or darker than others.

Why it matters

Uncorrected astigmatism causes eye strain, headaches, blurred vision at all distances and difficulty driving at night. Even small amounts can affect comfort during long screen use.

Who may benefit

Anyone with blurry vision, frequent headaches, or trouble with night-time glare. About 1 in 3 people has some astigmatism. Dr. Roxanna Gangi can confirm with a quick refraction.

Disclaimer: This tool is for educational purposes only and does not replace a professional eye examination. Screen brightness, calibration, lighting and viewing distance all influence results. For an accurate assessment, request a comprehensive exam with Dr. Roxanna Gangi, your trusted Optometrist in Toronto and York Region.

How to take this test

  1. If you wear glasses for distance, remove them.
  2. Sit about 40 cm (16 inches) from the screen.
  3. Cover one eye and stare at the centre of the chart.
  4. Do all lines look equally dark and sharp, or do some stand out?
  5. Repeat with the other eye.

Take the test

If some lines look darker, thicker or sharper than others, that may indicate astigmatism. A proper measurement requires a refraction with Dr. Roxanna Gangi, Optometrist.

Frequently asked questions

Want a real, in-person assessment?

Online tools are a great starting point, but a comprehensive eye exam with Dr. Roxanna Gangi can detect conditions that screen-based tests cannot — including glaucoma, diabetic retinopathy, and early macular changes.

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