Stockholm, Oct. 4 (Reuters): Two Americans and a German won the 2005 Nobel Prize in Physics today for work in optics enabling extremely accurate measurements of time and distance with future applications in telecommunications or space travel.

The Royal Swedish Academy of Sciences awarded the prize to Americans Roy Glauber and John Hall and Germany’s Theodor Haensch for studying light and harnessing lasers to create a “measuring stick” to gauge frequencies with extreme precision.

“We get most of our knowledge of the world around us through light,” said the Academy, calling optics “the physicists’ tool for dealing with light phenomena”.

The winning trio’s research answered such questions as how candle light differs from laser beams in a CD player and how light can measure time more accurately than an atomic clock.

Harvard University’s Glauber, who is 80, wins half of the 10 million Swedish crown ($1.29 million) prize for his theoretical description of the behaviour of light particles and establishing in 1963 the basis for quantum optics.

“He could explain the fundamental differences between hot sources of light such as light bulbs, with a mixture of frequencies and phases, and lasers which give a specific frequency and phase,” it said.

Decades later, Hall and Haensch, from the University of Colorado and the Ludwig-Maximilians-University in Munich respectively, worked on determining the colour of the light in atoms and molecules with extreme precision.

Haensch, who is 63, used even-spaced laser pulses “like the teeth of a comb or the marks on a ruler” to determine the value of frequencies and Hall, who is 71, refined this technique.

Their findings “have made it possible to measure frequencies with an accuracy of fifteen digits”, for use in highly accurate clocks and new technology for global positioning systems, said the academy citation.

This could be put to use in giving GPS navigation enough accuracy for long space journeys and for space-based telescopes, but might also be used in telecommunications.

“We might eventually enjoy 3D holographic television as a possible application,” Haensch said from Munich. Describing himself as “overwhelmed, happy and speechless”, he said he was busy packing for a US trip.

“I have no time to celebrate right at the moment”, he said.