Do you have even heard about laser pointer or laser pointer pen? You must know about them if you know the history of eBay. This e-shop which was established in 1995 has 16 billion users now and it becomes as the best auction website in the whole world. People can buy everything from it except for the prohibited products. The birth of eBay can be attributed to Pierre Palma's fiancée. Because she was worried that she can not collect gadgets after they moved to Silicon Valley. So Pierre Palma established a big auction website to hope that all people can buy everything they want without going out. And the first product which was sold by this website is the laser pointer. Certainly, the laser pointer can be used by many ways today.
Nobody can resist the laser pointer is a good helper for doctor teaching. As we all know, when a professional doctor explains the sample lesions for his students, he can not point the specific parts by hands. Or the dangerous germs will invade into body and cause serious disease. But if he does not point out them, the students can not understand the difficult knowledge. Thus, a laser pointer can help him easily. The clear and straight laser light can find out the specific parts without any risk.
The laser pointers can be divided as three kinds according to different colors. The red laser pointer uses wavelength of 650nm-660nm. It is a kind of laser which is used in DVD disc. This kind of laser pointer is the earliest and most popular and its price is usually cheap at the same time. While the laser light of green laser pointer is always used in blue-ray disc and the feature of this solid laser light is high visibility. The last one is the blue-purple laser pointer, which is widely used to detecting money.
The biggest difference between laser pointer and laser pointer pen is the shape actually. But more teachers, trainers or lecturer intend to choose the laser pointer pen which can help them to demonstrate their lesson and project. Besides, the multimedia is very popular in classroom, so some later pointer pen can be also used as remote control. Teachers can control the computer or projector easily according to course schedule.
But you should use it for a long time, because some powerful laser pointer will have heat effect to hurt others.
No comments:
Post a Comment