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Title: Optical key system

An optical key system comprises a battery-operated optical key and an isolated lock that derives both its operating power and unlock signals from the correct optical key. A light emitting diode or laser diode is included within the optical key and is connected to transmit a bit-serial password. The key user physically enters either the code-to-transmit directly, or an index to a pseudorandom number code, in the key. Such person identification numbers can be retained permanently, or ephemeral. When a send button is pressed, the key transmits a beam of light modulated with the password information. The modulated beam of light is received by a corresponding optical lock with a photovoltaic cell that produces enough power from the beam of light to operate a password-screen digital logic. In one application, an acceptable password allows a two watt power laser diode to pump ignition and timing information over a fiberoptic cable into a sealed engine compartment. The receipt of a good password allows the fuel pump, spark, and starter systems to each operate. Therefore, bypassing the lock mechanism as is now routine with automobile thieves is pointless because the engine is so thoroughly disabled.
Authors:
 [1] ;  [2]
  1. (Livermore, CA)
  2. (Danville, CA)
Publication Date:
OSTI Identifier:
872969
Report Number(s):
US 6055079
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Patent
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Country of Publication:
United States
Language:
English
Subject:
optical; key; comprises; battery-operated; isolated; lock; derives; operating; power; unlock; signals; correct; light; emitting; diode; laser; included; connected; transmit; bit-serial; password; user; physically; enters; code-to-transmit; directly; index; pseudorandom; code; person; identification; retained; permanently; ephemeral; send; button; pressed; transmits; beam; modulated; information; received; corresponding; photovoltaic; cell; produces; operate; password-screen; digital; logic; application; acceptable; allows; watt; pump; ignition; timing; fiberoptic; cable; sealed; engine; compartment; receipt; fuel; spark; starter; systems; bypassing; mechanism; routine; automobile; thieves; pointless; thoroughly; disabled; emitting diode; operating power; laser diode; optic cable; power laser; photovoltaic cell; light emitting; digital logic; optical key; modulated beam; responding optical; fiberoptic cable; light modulated; timing information; fuel pump; correct optical; /359/307/340/