| 摘要 |
PROBLEM TO BE SOLVED: To provide a time counting device capable of precisely detecting a time interval. SOLUTION: Ultrasonic wave is generated by impressing an electrical pulse P<SB>j</SB>on an oscillation body 220 by one pulse portion, and at the detection part 230 the pulse generated by the ultrasonic wave is detected as a 1st timing. By recognizing the 1st pulse, electrical pulses Q<SB>k</SB>having different period from the pulse P<SB>j</SB>are outputted. The number of electrical pulses C of the pulses P<SB>j</SB>are counted from the 1st timing to a 2nd timing at which 2 continuous electrical pulses of Q<SB>k</SB>are generated between the electric pulses P<SB>j</SB>. At the calculation part 380 the time interval T<SB>g</SB>from the 1st timing to the time of the pulse P<SB>j</SB>outputted, immediately after the 1st timing, is calculated according to the formula (C/m)*T<SB>p</SB>. By constituting a time scale with a vernier it is possible to perform a high precision calculation. COPYRIGHT: (C)2005,JPO&NCIPI
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