17 results found for optics

Parabolic surfaces can be used to concentrate energy for example to focus sunlight to heat things. Using an old World War II spot light mirror we demonstrate how easy it it is to concentrate enough energy to cause combustion. Finally, we show how to ....

An elegantly simple optical diffraction demonstration with an inexpensive laser pointer is used to show the way in which x-rays can reveal the structure of crystals, and in particular, the double helix structure of DNA.

The main problems associated with communicating with distant space probes like Voyager 1 are investigated. The role played by diffraction in limiting the amount of power receivable on Earth is discussed. The further problems of reaching a nearby st....

A brief look at the Physics behind sending signals along cables and via geostationary satellites. An experiment to measure the speed of an electrical pulse in a cable is described and the Physics of the orbits of communcations satellites is develope....

Charles Falco describes his and David Hockney's theory of the use of optical devices by mediaeval artists.