Patent · US Expired

Laser alignment system with modulated field

US4674870A · kind A · utility

52Cited by
16References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 18, 1985
Grant dateJun 23, 1987
Priority date
Expiry dateOct 18, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01C15/004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A laser alignment system includes a transmitter and one or more receivers. The transmitter produces an alignment field by projecting laser energy in a non-planar reference cone, and the receivers locate this reference cone with photodetectors. The laser energy in the alignment field is modulated at 8 kHz and the signals produced by the photodetectors are filtered and amplified to increase the range of the system. Each receiver operates a display which indicates when it is aligned in the reference cone, and it produces an out-of-level indication when the transmitter is not properly aligned.

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