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A picosecond is an SI unit of time equal to 10−12 or 1/1,000,000,000,000 of a second. That is one trillionth, or one millionth of one millionth of a second, or 0.000 000 000 001 seconds. A picosecond is to one second as one second is to 31,710 years. Multiple technical approaches achieve imaging within single digit picoseconds. For example the Streak camera or intensified CCD (ICCD) cameras are able to picture the motion of light. 〔(【引用サイトリンク】title=Trillion-frame-per-second video )〕 〔(【引用サイトリンク】title=Ultra high speed CCD cameras capture the motion of light. )〕 The name is formed by the SI prefix ''pico'' and the SI unit ''second''. It is abbreviated as ''ps''. One picosecond is equal to 1000 femtoseconds, or 1/1000 nanosecond. Because the next SI unit is 1000 times larger, measurements of 10−11 and 10−10 second are typically expressed as tens or hundreds of picoseconds. Some notable measurements in this range include: *shorter times * 1.0 picoseconds (1.0 ps) – cycle time for electromagnetic frequency 1 terahertz (THz) (1 x 1012 hertz), an inverse unit. This corresponds to a wavelength of 0.3 mm, as can be calculated by multiplying 1 ps by the speed of light (approximately 3 x 108 m/s) to determine the distance traveled. 1 THz is in the Far infrared. * 1 picosecond – time taken by light in a vacuum to travel approximately 0.30 mm * 1 picosecond – half-life of a bottom quark * ~1 picosecond – lifetime of a single (hydronium) ion in water at 20°C〔(【引用サイトリンク】title= Lifetime of single hydronium (H3O+) ion at 20°C )〕 * picoseconds to nanoseconds – phenomena observable by dielectric spectroscopy * 1.2 picoseconds – switching time of the world's fastest transistor (845 GHz, as of 2006)〔(【引用サイトリンク】title=World's Fastest Transistor Approaches Goal of Terahertz Device )〕 * 1.7 picoseconds - rotational correlation time of water * 3.3 picoseconds (approximately) – time taken for light to travel 1 millimeter * 10 picoseconds after the Big Bang – electromagnetism separates from the other fundamental forces * 10–150 picoseconds – rotational correlation times of a molecule (184 g/mol) from hot to frozen water * 108.7827757 picoseconds – transition time between the two hyperfine levels of the ground state of the caesium-133 atom at absolute zero * 330 picoseconds (approximately) – the time it takes a common 3.0 GHz computer CPU to add two integers *Longer times ==See also== * SI unit * Second * Nanosecond * Microsecond * Millisecond * Jiffy (time) * Orders of magnitude (time) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「picosecond」の詳細全文を読む スポンサード リンク
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