Optical key system
US6055079A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1997 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Aug 7, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60R25/00
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
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 …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.