| 摘要 |
<p>An apparatus for measuring the distance of a target includes a circuit arrangement of a transmitting circuit, a first receiving circuit, a second receiving circuit, a charging/discharging circuit, a switching gate, an analog-to-digital converter, a microprocessor, and a monitor. A modulated pulse signal is emitted by the transmitting circuit, and will be received by the first receiving circuit which makes the charging/discharging circuit start being charged. When the modulated pulse signal is reflected from a reflective object, it will be received by the second receiving circuit and the second receiving circuit will send a stop signal to terminate the charge to the capacitor of the charging/discharging circuit. By calculating the time period of the charging time under the control of switching gate, analog-to-digital converter, microprocessor, the distance of a target object is measured. Further, the modulated pulse signal received by second receiving circuit will be received by the microprocessor so as to determine whether the infrared ray received is the originally emitted modulated signal by transmitting circuit. <IMAGE></p> |
