Of course. Nowadays, more and more people use computers and ipads to work, play or chat with friends. As a result, more people feel tired eyes and watery eyes at the close of a day. To make it clear, any electronic products can release some radiation and cause light pollution. Especially some products with small sreens like phone and ipad, can make people's eyes tired after playing hours with them. At most times, people use these electronic products to play games and read electronic books. They need to keep looking at the screen with the pictures on it changing rapidly. They may feel excited and forget about the rest for eyes. In fact, their eyes are tired, but they usually don't realize it. For children, younger than 4, using these electronic products too long and too often can lead to the damage to their eyes lifelong, because the age between 0 and 4 is the key period of eye development.
It's hard to say. Short time using electronics products can not hurt our eyes, while over time using those products can cause a lot of problems for our body, especially for eyes, which including near sight, blurry eyes, eye fatigue and so on. Have a short time break after using electronics products for more than an hour to keep your eyes healthy.
Electronics products such as computer and ipad are not harmful to eyesight permanently. But they are the cause of eye strain or the aggravation of existing eye problems. If you stare at the screen for more than three hours every day, you will feel eye discomfort, headache, eye itchiness, dry or watery eyes, eye burning, blurriness, difficulty focusing and problem of color perception. Besides, using electronics products for nine or more hours a day in the long term will also lead to weakness in eyesight that causes incurable blindness consequently. So I suggest you control the time of using computers, ipad and other products. In addition, you should also blink your eyes more frequently when you are using them.