You asked

Is it ok for my child to use the computer?

In a lot of households today, the home computer or laptop is a staple feature and most kids have some access to it. There are some divided opinions about allowing children to use computers but it’s not all bad; studies have shown that children of a preschool age are more “school ready” having already had some experience on the computer and have developed better cognitive skills.  However, computer usage should be monitored and only allowed in moderation. It’s best that you have a clear outline of how much time you allow your child to spend on the computer.  Vision problems related to computer usage can occur in both adults and children.
Although myopia (short sightedness) is a hereditary trait, it is thought that computer eyestrain can affect its development.  In working to see the computer screen the eye has to work to focus on it, and it is thought that this repeated effort to focus, can cause a strain on the eye.  Based on this theory, there should be limited time allowed on the computer, and there should also be breaks after every 20 minutes to allow the eye muscles to relax.
Suitable work stations
Computer work stations should be ergonomically suitable for children. The recommended distance between the eye and the monitor is 18 to 28 inches. Viewing computer screens closer than this can cause eye strain.
You should also check the lighting in the room; to reduce glare, windows and light sources should not be directly visible on the computer screen.
Computers form an important part of school and home life, and when used correctly are safe for your child to enjoy, however you should avoid prolonged use and you should always encourage other activities be they indoor or outdoor. 
If you are concerned that your child is developing vision problems as a result of using the computer, you should have their eyes tested.

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