Computer mouse The basic computer mouse is an amazingly clever invention with a relatively simple design that allows us to point at things on the computer and it is very productive. Think of all the things you can do with a mouse like selecting text for copying and pasting, drawing, and even scrolling on the page with the newer mice with the wheel. Most of us use the computer mouse daily without stopping to think how it works until it gets dirty and we have to learn how to clean it. We learn to point at thing before we learn to speak, so the mouse is a very natural pointing device. Other computer pointing devices include light pens, graphics tablets and touch screen, but the mouse still our workhorse. How does the mouse work? We have to start at the bottom, so think upside down for now. It all starts with mouse ball. As the mouse ball in the bottom of the mouse rolls over the mouse pad, it presses against and turns two shafts. The shafts are connected to wheels with several small holes in them. The wheels have a pair of small electronic light-emitting devices called light emitting diodes mounted on either side. One LED sends a light beam to the LED on the other side. As the wheels spin and a hole rotates by, the light beam gets through to the LED on the other side. But a moment later the light beam is blocked until the next hole is in place. The LED detects a changing pattern of light, converts the pattern into an electronic signal, and sends the signal to the computer through wires in a cable that goes out the mouse body. This cable is the tail that helps give the mouse its name. The computer interprets the signal to tell it where to position the cursor on the computer screen. 1. Most computer users want to know how the computer mouse works. 2. According to the author, general computer users need not know how the computer mouse was invented. 3. The computer mouse derives its name from the cable that goes out its body, which looks like the tail of a mouse. 4. The key components of a computer mouse are the two LEDs. 5. When an ordinary computer mouse gets dirty, it has to be replaced with a new one. 6. The most durable computer mice on sale are the IBM ones. 7. The optical mouse is superior to the basic one in that the former has no moving parts.
上一篇: 职称英语阅读理解考试专项复习(4)
首款马蹄专用跑鞋面世
体坛英语资讯:Chinas winter sports industry ushers in golden age
西班牙罗宾汉餐厅'劫富济贫'
BBC推荐:五月必读书单[1]
2017年6月英语四级作文模板:应用写作型范文
Great Barrier Reef destruction, mission to clean space 澳洲大堡礁珊瑚大规模死亡、清理太空垃圾
Garden path?
布拉德•皮特首谈离婚 承认酗酒自作自受
英语四级作文范文:大学生兼职
体坛英语资讯:Chinese fans pleased with Yao Mings appointment to FIBA Central Board
国际英语资讯:Former Brazilian president involved in corruption scheme: former Petrobras executive
那些有关爱情的习语(一)
英语六级作文范文:出国留学
体坛英语资讯:Neymar ordered to stand trial over Barcelona move
Mansplaining 男人说教
国内英语资讯:Spotlight: Aviation experts hail strong momentum of Chinas aviation industry
国际英语资讯:At least 31 dead in school bus crash in Tanzania
国务院印发《“十三五”脱贫攻坚规划》
The fear of missing out 错失恐惧症
奥黛丽·赫本1989年在联合国的演讲:为了孩子们
想获得女生青睐?那就多吃瓜果蔬菜!
川普放宽执行对宗教团体从事政治活动的禁令
国内英语资讯:Forty five sentenced for deadly Shenzhen landslide
四六级8大主题翻译关键词
蒂勒森要求东盟降低和朝鲜的外交关系
国内英语资讯:Syngentas shareholders accept ChemChina merger offer
国际英语资讯:French voters brace for decisive round of presidential election
哪些大脑秘密,只有神经学家懂
一周热词榜(11.26-12.2)[1]-12.2)
英语四级作文范文:人工智能