Drone-zapping laser weapons now effective (and cheap) reality

A single burst of light is precisely aimed at a tiny drone flying at breakneck speed far in the distance. Instants later, the deactivated drone crashes into the sea. Not a sound made, no human casualties, no messy explosions. ...


New invention for more efficient atomic force microscopes

The basic principle of the atomic force microscope is very simple: an extremely thin, movable tip on a cantilever is moved over a surface that is being examined. Tiny forces on an atomic scale act between the tip and the ...

Electronics & Semiconductors

New microchip links two Nobel Prize-winning techniques

Physicists at Delft University of Technology have built a new technology on a microchip by combining two Nobel Prize-winning techniques for the first time. This microchip could measure distances in materials at high precision—for ...

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A laser is a device that emits light (electromagnetic radiation) through a process called stimulated emission. The term laser is an acronym for light amplification by stimulated emission of radiation. Laser light is usually spatially coherent, which means that the light either is emitted in a narrow, low-divergence beam, or can be converted into one with the help of optical components such as lenses. Typically, lasers are thought of as emitting light with a narrow wavelength spectrum ("monochromatic" light). This is not true of all lasers, however: some emit light with a broad spectrum, while others emit light at multiple distinct wavelengths simultaneously. The coherence of typical laser emission is distinctive. Most other light sources emit incoherent light, which has a phase that varies randomly with time and position.

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