Reference no: EM132615146

1. Mark an X close to the left edge of a piece of paper (see above, printed or drawn by hand is OK). Hold the paper in front of you at about 45 cm from your eye. The X should be directly in front of your right eye with the rest of the blank page off to the right.

2. Close your left eye and look at the X with your right eye. Hold the tip of a pen/finger in front of the X on the paper so that the pen/finger covers the X.

3. Slowly move the pen/finger across the page to the right away from the X while still looking directly at the X, viewing the pen/finger with your peripheral vision.

4. Mark the paper at the position where the tip of the pen/finger disappears (it will be about 15 cm to the right of the X when the paper is at about 45 cm distant from your face). At this point the image of the pen/finger has fallen on the blind spot of your right eye. Move the pen/finger slightly left and right and up and down to get a sense of the size of the blind spot. Measure and record the distance on the paper in cm from the X to the mark. You will use this distance along with the distance of your eye from the paper to calculate the off axis angle of the blind spot.

5. Turn the paper upside down so the X is now on the right edge of the paper, close your right eye, and repeat steps 1 - 4 for your left eye, moving pen/finger to the left until it disappears to locate the blind spot for your left eye.