Communicating with light
Most of the data we generate and receive (whether emails, tweets, videos or mobile calls) are now carried by optical fibres, which use light to transmit vast quantities of information over trans-oceanic distances. The use of hundreds of wavelengths ....
More details | Watch nowFrom Millisecond to Attosecond Laser Pulses
A historical overview is presented of the experimental development of ever shorter laser pulses from 1960 to the present. Already in the early sixties nanosecond pulses were achieved and the entry into the picosecond domain was reached in the late s....
More details | Watch nowThe Optical Frequency Comb – a Really Versatile Tool
The Optical Frequency Comb concept and technology exploded in 1999-2000 from the synthesis of advances in independent fields of Laser Stabilization, UltraFast Lasers, and NonLinear Optical Fibers. The Comb was developed first as a method for optical....
More details | Watch nowWhat is Quantum Optics?
The image of light waves as oscillating electromagnetic fields explains virtually all the phenomena of traditional optics. An awareness that these waves are somehow subdivided into quanta has however been with us since the early 20th century. The....
More details | Watch nowThe Fresnel Lens
Early lighthouses used coil and wood fires before moving on to gas and then electricity powered lights. Massive improvements took place by using a lens system around the light. The development of the Fresnel lens brought what we now regard as the....
More details | Watch nowOptical science in the fast lane
In this talk Wilson Sibbett introduces some of the underlying concepts that have enabled us to develop practical ultrafast lasers and a selection of applications that range from the fundamentals of chemical bonding to weapons decommissioning!
More details | Watch nowLight Beam
Light is reflected off a flexible shiny surface fixed to the end of a plastic tube. When one speaks into the tubes sound vibrations pass down the tube and make the surface vibrate. The reflected light is therefore sent off from the surface in a con....
More details | Watch nowParabolic Light Collectors
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 ....
More details | Watch nowHow X-rays cracked the structure of DNA
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.
More details | Watch nowCommunication with Space Probes and beyond
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....
More details | Watch nowCommunication on Earth, using Cables and Satellites
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....
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