×

Sensors and systems for detecting environmental conditions or changes

  • US 7,812,731 B2
  • Filed: 12/22/2006
  • Issued: 10/12/2010
  • Est. Priority Date: 12/22/2006
  • Status: Expired due to Fees
First Claim
Patent Images

1. A system for detecting a predetermined environmental condition, wherein the system comprises:

  • a device capable of providing information, wherein the device comprises a passive RFID transponder;

    a non-human interrogator configured to read information provided by the device, wherein the interrogator comprises an RFID reader configured to transmit power to the passive RFID transponder, and the passive RFID transponder is configured to transmit information to the RFID reader when the passive RFID transponder receives power from the RFID reader; and

    a shield, the shield having a first condition and a second condition, wherein in the first condition the shield comprises a conductive material configured to preclude at least one of the transmission of power from the RFID reader to the passive RFID transponder and the transmission of information from the passive RFID transponder to the RFID reader, in the second condition the shield is configured to permit the transmission of power from the RFID reader to the passive RFID transponder and to permit the transmission of information from the passive RFID transponder to the RFID reader, and the shield is configured to transition from the first condition to the second condition when the shield is exposed to the predetermined environmental condition; and

    wherein the interrogator indicates that the predetermined environmental condition exists when the shield transitions to its second condition, the passive RFID transponder receives power from the RFID reader and transmits the information to the RFID reader, and the RFID reader receives the information from the RFID transponder.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×