| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce a noise component to detect a position of a body highly precisely. SOLUTION: This detector is provided with a transmission antenna 6 for transmitting an electromagnetic wave, a receive antenna 10 for receiving the wave, a sampling means 14 for sampling a received signal from the transmission antenna 10, a low-path filter means 54 for attenuating a high frequency range of the sampled signal, and a signal computing processing means 38 for processing an output signal from the low-pass filter means 54 to measure the position of the body. The low-pass filter means 54 includes a time constant variable amplifier for varying a time constant by controlling a gain voltage.</p> |
