| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To accurately measure the distance at a high-speed and high accuracy, in which the arrival times of a reference wave and a reflected wave are determined accurately. <P>SOLUTION: In receiving the reflected wave R from the object of a pulse-like electromagnetic wave projected toward an object 9 by a receiving part, in receiving a reference wave S diverged from the electromagnetic wave through a known distance by the receiving part, in separating the signals of both the waves outputted from the receiving part to calculate the differential time between both the waves, and in measuring the distance to the object on the basis of the differential time, a time T<SB>VO</SB>at which the wave height of the signal pulses of the reference wave and the reflected wave reaches to a first threshold level VO, the time at which it reaches to a second threshold level AVO which is an integral multiple of the first threshold level, and T<SB>AVO</SB>are measured. A signal pulse rising time T<SB>Af</SB>is calculated by both the times. The distance to the object is measured by calculating the differential time on the basis of the obtained rising time T<SB>Af</SB>. <P>COPYRIGHT: (C)2004,JPO</p> |
