That is 2-all then!” the referee announces. Round The Role of Devices . “Light can be delivered and controlled with high precision!” says the third member. He describes that, as far back as 800 years ago, monks used magnifying glasses (which bend light) to help them copy ancient books. They describe laser pointers, used to create special effects in movies and entertainment parks (Figure 2A). Then, Team Light’s captain asks the audience, “Does anyone have a £5 note I could borrow?” An audience member hands one over, and the team captain points out the note’s hologram of Big Ben, London’s famous clock tower.
We are so good at controlling light that we can make images seem three dimensional, even though they are flat! We call these images “holograms”” he says. Figure 2 - We use devices based on precise light or sound delivery in our everyday lives. Figure 2 - We use devices based on precise light or sound delivery Spain phone number list in our everyday lives. (A) A cat playing with the spot of light coming from a laser pointer. (B) Speakers can be arranged, typically along the shape of the letter “J” or of a banana, to maximize sound delivered in a certain direction, as you might have experienced at concerts or simply in the assembly room of your school.
Sonar uses a beam of sound to detect objects underwater, for instance obstacles in a submarine. The shape is created by interference, caused by controlling electronically the timing of different ultrasound speakers. (D) An early acoustic lens built at Bell labs in 1950s. In the picture, that can be found here, the lens (center) is as big as the engineer on the right (photograph credits: iStockphoto.com). “After centuries of using lenses, mirrors, and filters, we have achieved such great control of light that most of us now carry a light-controlling device in our pockets, every day.