Patent · US Expired

People and object counting system

US4303851A · kind A · utility

47Cited by
7References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 16, 1979
Grant dateDec 1, 1981
Priority date
Expiry dateOct 16, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07C9/00
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The perimeter of an area is scanned along two adjacent paths which define spacially resolved gates through which objects and people must pass to enter and leave the area. As the gates are scanned, the presence of objects and people are detected. A complete scan produces a gate signature which includes information indicative of the presence and location of objects and people in each gate during the scan. Successive signatures are compared in sequence as scans are made in order to determine changes caused by movement of objects and people in or out of the area. From this comparison an up/down counter is controlled to maintain a dynamic count of the number of objects or people in the area following each scan of the gates. The counter counts up as objects and people enter the area and counts down as they leave.

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