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在现代科学技术中,许多地方都要求测量极短的时间间隔。比如,在用雷达或激光测距时,测距的精确度主要取决于对时间测量的精度。已知电磁波及光的传播速度为C,如果从发送一个脉冲到被目标反射回来的时间为t,则目标的距离就是:d=ct/2,C=3×10~10cm/秒。所以,如果测时的分辨率可以到1毫微秒(10~-9秒),那么测距的分辨率就可以达到15cm。又如,在核物理实验中,常要测量粒子的速度、寿命等,这也需要借助电子技术将它们转换成时间间隔来进行测量。在电工及无线
In modern science and technology, many places require measurement of extremely short time intervals. For example, when using radar or laser ranging, the accuracy of ranging mainly depends on the accuracy of time measurement. It is known that the propagation speed of electromagnetic wave and light is C, and the distance between the target and the target is: d = ct / 2 and C = 3 × 10 ~ 10 cm / s if the time from transmitting a pulse to being reflected by the target is t. So, if the resolution of the time measurement can be 1 nanosecond (10 ~ -9 seconds), then the resolution of the distance can be up to 15cm. As another example, in nuclear physics experiments, the particle velocity, life expectancy and so on are often measured, which also need to be converted into time intervals for measurement by means of electronic technology. In electrician and wireless