| 摘要 |
PURPOSE:To measure the length of a target easily and accurately by detecting a point which abruptly changes at the detection starting position of the target and the detection terminating position, measuring the interval between those changing points and finally performing an operation based on the interval thus obtained. CONSTITUTION:When a wave transmitter-receiver 12 begins to detect a target 11 as it reches the position of D by moving to the right, the level of a standard signal m begins to fall, and the signal m shows the lowest level when the transmitter-receiver 12 reaches the position of E. And, the level of the standard signal m abruptly rises when the transmitter-receiver 12 reaches the position of F. On the other hand, a measuring signal n from the target 11 becomes a curve having changing points q and r when the transmitter-receiver 12 is positioned at D and G. Intervals between changing points, l-a, l+a, are obtained respectively and those values are added, and the length of the target, l, can be obtained by dividing the sum by 2. |
