Patent · US Expired

System and method for generating band-limited quasi-sinusoidal signals

US6031218A · kind A · utility

55Cited by
15References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 8, 1999
Grant dateFeb 29, 2000
Priority date
Expiry dateMar 8, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/03549
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method for generating quasi-sinusoidal signals includes illuminating an object capable of reflecting light, focusing a portion of the reflected light on a multi-element detector to form an image, and matching the image size to the size of the detector elements. A first weighted sum of signals generated by a first set of elements produces an in-phase signal, and a second weighted sum of signals generated by a second set of elements produces a quadrature signal. Weights are signed quantities selected to exhibit a band-pass behavior in the spatial frequency domain, thereby attenuating noise generated by, for example, non-uniform surface reflectance and non-uniform illumination.

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