Patent · US Active

LED emitter for optical traffic control systems

US7982631B2 · kind B2 · utility

9Cited by
6References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 2009
Grant dateJul 19, 2011
Priority date—
Expiry dateJan 7, 2030

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08G1/087
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A light emitter for a traffic control preemption system. The emitter includes a plurality of groups of infrared (IR) LEDs and a power source coupled to the groups of LEDs. A plurality of controlled current sources is coupled to the plurality of groups of LEDs, respectively. A controller is configured to trigger an IR light pulse pattern from the groups of LEDs and maintain a first level of IR radiant power from the groups of LEDs using individual control of respective current levels to the groups of LEDs in response to current sense levels from the groups of LEDs. The pulse pattern and first level of IR radiant power activate preemption in the traffic control preemption system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.