|
阅读理解。
The London Olympic Games are coming soon．This summer, Chinese sports fans will be able to watch the exciting games in 3-D on CCTV．
When you watch 3-D movies or TV, you have to wear a special pair of glasses．The 3-D glasses make the people and the things on the screen look like they are in the room with you．
3-D, means having three dimensions：width, height and depth．3-D technology is based on the way the human brain and eye work．Because the pupils of a person's eyes are about 6.5cm apart, when we look at something, each eye sees it from different angle．Our eyes send the two pictures to our brain, and the brain puts them together．The small difference between the picture from the right eye and the picture from the left eye make us see depth．
While watching 2-D films, we don't have to wear the special glasses．We see the pictures in two dimensions, each eye get the same information．This is because there is only one way of watching it．
So the aim of 3-D technology is to get a different picture into each eye of the person．It uses two film projectors．One projects a left eye picture and the other projects a right eye picture．When we are in the cinema, we can see different pictures in each eye at the same time with the help of the 3-D glasses．
While watching 3-D films, we feel that we are actually in the same environment as the things we are watching．However, some people are against watching 3-D films．One of the reasons is the 3-D glasses makes the screen of the film or TV look darker．It is bad for eyes．What's more, people with eye problems may get headaches if they spend too much time watching 3-D movies, because their brains need to work harder to “read” the pictures．
| 
