Patent · US Expired

Stepped etalon

US6246480A · kind A · utility

25Cited by
3References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 1, 1999
Grant dateJun 12, 2001
Priority date
Expiry dateSep 1, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01J9/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An improved stepped etalon comprises a transparent body having a stepped surface. Adjacent step lands are separated from each other by a transition region which includes a curved, waved, or otherwise varied step wall such that the average height of the stepped surface does not change abruptly in the transition region from the height of one land to another, but instead varies gradually according to the particular shape of the step wall. In an alternative embodiment, the step transition is formed using a grey-scale or half-tone patterning in which the average height gradually varies across the transition region. The non-planar transition region reduces the amount of coherent interference caused by the step transition thereby reducing the dead spot behind the step transition portions where interference prevents accurate measurements of light transmission from being made.

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