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Eye test
Test your eyesight yourself. Doing the various tests will help you to determine whether your visual field is still functioning properly or if you have to consult an optometrist. It is very important to know what your situation is when it comes to your range of vision. Many people have problems with their eyes or visual field without knowing it. Sometimes this is the case even though they wear glasses.
Under each test there is a description of what you should be able to see. If you do not see it or if you see a different image, we recommend that you pay a visit to the ophthalmologist.
Amsler Grid
The amsler grid is a simple and easy test to determine whether there are variations in your eyesight. We recommend people with Macular Degeneration to do this test various times a week.
Instructions
1. If you wear glasses or contact lenses, wear them during the test.
2. Assume a comfortable reading distance from the test.
3. Cover one eye.
4. Look at the amsler grid. Keep your eye focused on the black dot in the middle.
5. Look at the lines in the grid without moving your eyes. All the lines should be straight and all the squares should look the same. There are no white, black or distorted areas.
6. If you notice any abnormality, call your ophthalmologist immediately.
7. Check the other eye.
Test color blindness
  
Eye test/colors
What do you see in this picture?
Can you see the number ’182’ ?
If this is the case, then everything is in order.
Can you see the number ’8’ ?
When you can only see the number ’8’, this may indicate e ”red-green” anomaly.
Test visual field
What you can see out of the corners of your eyes is often important. Discover how wide your range of vision is. Do not wear glasses when doing this test.
Take a pen in your hand and hold your outstretched arm in front of your face. Cover the eye that is opposite the outstretched hand with your free hand. Look straight ahead. Keep looking straight ahead while slowly moving the pen in outward going circles with your arm still outstretched. At the point where the pen disappears from your visual field you stop movement.
If your visual field is normal, your arm should now be at an angle of 90 degrees from the starting point of movement. Move the outstretched arm back along the same route, beyond the starting point until the pen disappears at the other end of your visual field. The angle of the arm in relation to the starting point of movement should now be somewhat smaller at an angle of about 60 degrees.
Test depth vision
Depth vision within a distance of 2 meters is a function that requires both eyes. When someone suddenly loses sight in one eye, he will have problems with depth calculation. At first he will probably pour his coffee or tea beside the cup and it will be difficult for him to notice steps. After a few months he will adapt himself to the situation and these problems will disappear.
For depth vision at more than 2 meters we use other perceptions in order to assess the distance and depth:
- Perspective
- Shadows
- Change in color
- Relative size
- Overlapping images
One simple way to experience the consequences of depth vision is to close one eye and let your two forefingers touch each other right in front of your eyes. It’s not as easy as you think!
 Many tricks can be performed with depth vision. Do these horizontal lines look straight or are they curved?
Take a good look.
Astigmatisme
Astigmatism is a disturbance in your eyesight. You see things unclearly, because the cornea and in a lesser degree also the lens are curved irregularly, so that the rays going out from one point can no longer join, resulting in blurred images. This may be a congenital defect but can also be caused by keratitis (inflammation of the cornea).The use of cylindrically formed glasses (or lenses) can sometimes improve the wearer’s eyesight.
Now concentrate on each of the four circles and look at the lines. Do you see even, distinct, dark lines?
When you see the lines as having an evenly black color with even spacing between them, there is no astigmatism. If however, the lines are perceived as being frayed, greenish or distorted, this may indicate astigmatism. This problem can be corrected by wearing glasses or contact lenses.
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