| 摘要 |
An apparatus for remote temperature reading particularly for the reading of the temperature of an article or animal at a distance by means of an electromagnetically interrogatable label attached to or implanted in the article or animal the label being constructed to be capable of receiving an electromagnetic signal from a transmitter, converting the signal to a surface acoustic wave, passing the wave over a path on the label, reconverting the surface acoustic wave to an electromagnetic signal and retransmitting it to a receiver. The path of the surface acoustic wave is of a material such that the time of travel of the surface acoustic wave over the path is a function of the temperature of the path and thus of the label. The receiver is constructed to measure the time interval between electromagnetic signals produced by the passage of the surface acoustic wave past a transducer or transducers in the path and thereby provide an output indicative of the temperature of the environment of the label. It is preferred that the label includes a plurality of transducers at coded locations along the path arranged for retransmitting to the receiver a coded sequence of electromagnetic signals indicative of an article or animal to which the label is affixed or in which it is implanted in the manner described in U.S. Pat. No. 3,706,094. |
