Take a
closer look.

1. Place a physical ruler against the screen and adjust the line to exactly 50 mm. Measure the distance from your eye to the screen and enter it in metres.
2. In good lighting, check each eye separately, covering the other without pressure. If you use your usual distance correction, note whether you are wearing it; do not change it based on this tool.
3. Name the symbols or gap directions. The row level describes nominal size, not measured visual acuity or dioptres. These letters and digits are not a certified clinical chart.
4. Recheck the line after changing browser zoom or moving the window to another display. Use one or three rows if the chart does not fit. Do not move closer without updating the measured distance.

Self-observation does not replace an ophthalmologist’s examination. A normal-looking chart does not guarantee the absence of disease.

1. In good lighting, cover one eye without pressure and look at the centre. Repeat with the other eye.
2. Compare the apparent sharpness and darkness of the directions. All lines use the same geometry; the screen can also affect their appearance.
3. Differences do not diagnose a condition or determine the strength or axis of correction. Discuss changes with an ophthalmologist.

Self-observation does not replace an ophthalmologist’s examination. A normal-looking chart does not guarantee the absence of disease.

1. Use good lighting. View from about 30–40 cm with your usual reading glasses if needed. Cover the other eye without pressure.
2. Keep looking at the central dot; do not follow the lines with your eyes. Notice bent, blurry or missing areas. View the light and dark stages separately for each eye.
3. This is an extended rectangular grid, not the standard square chart. It does not guarantee standard field coverage and does not test peripheral vision. Contact an ophthalmologist about new distortions.
4. A scotoma is an area of reduced or absent visual sensitivity. Relative scotomas involve reduced sensitivity; absolute scotomas involve absent sensitivity. This grid and colour inversion cannot reliably determine the type, cause or boundaries of a scotoma. The two polarities are this tool’s sequence, not a universal medical protocol.

Self-observation does not replace an ophthalmologist’s examination. A normal-looking chart does not guarantee the absence of disease.

Sudden flashes, many new floaters, a shadow or curtain, or sudden loss of vision require immediate medical attention. Do not delay care to complete these checks. The grid cannot rule out a retinal tear or detachment.