Patent · US Expired

Optical traffic preemption detector

US5202683A · kind A · utility

33Cited by
13References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 24, 1991
Grant dateApr 13, 1993
Priority date
Expiry dateJun 24, 2011

Classification

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

Abstract

An optical traffic preemption detector detects pulses of light emitted by an approaching emergency vehicle and provides an output signal which is processed by a phase selector. The phase selector can request a traffic signal controller to preempt a normal traffic signal sequence to give priority to the emergency vehicle. A detector assembly is mounted in proximity to an intersection and can have multiple detector channels. A detector channel can have multiple photocells. A detector housing includes a base, at least one detector turret and a cap. A detector channel circuit includes a circuit board, a photocell with a lens placed over the photocell, and circuitry to produce an output signal.

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