发明名称 |
Environmental indicator device and method |
摘要 |
A device for monitoring environmental exposure includes an element whose electrical properties change, in a predetermined way, in response to the environmental exposure. The element may be part of a tuned circuit or of a shield for a tuned circuit. In either case, when the tuned circuit is interrogated, preferably by an r.f. or microwave signal, it emits a signal whose intensity depends on the electrical properties of the element. Thus, an incremental environmental exposure can be measured by a change in the signal intensity. The device is particularly useful for monitoring the condition of perishable materials, because it can be located with the perishable inside a packaging material during both storage and interrogation.
|
申请公布号 |
US4646066(A) |
申请公布日期 |
1987.02.24 |
申请号 |
US19850749326 |
申请日期 |
1985.06.27 |
申请人 |
ALLIED CORPORATION |
发明人 |
BAUGHMAN, RAY H.;ELSENBAUMER, RONALD L.;IQBAL, ZAFAR;MILLER, GRANVILLE G.;ECKHARDT, HELMUT |
分类号 |
G01D5/12;G01D5/48;G01N27/12;G08B21/18;(IPC1-7):G08B13/18;G08B21/00 |
主分类号 |
G01D5/12 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|