Patent · US Expired

Optical module for an optically based measurement system

US5412330A · kind A · utility

98Cited by
12References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1993
Grant dateMay 2, 1995
Priority date
Expiry dateJun 16, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/308
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An optical module for an optically based measurement system, such as an electro-optic system (10) for measuring electrical characteristics of a device under test (14), has a probe arm (26), a layer of electro-optic material (27), and a first optical system for delivering a measurement beam (44) to the layer and for producing therefrom an information-carrying beam having optical characteristics indicative of the electric characteristics. The first optical system includes a first lens (128), and (optional) polarization bias adjustment (130), a dichroic beamsplitter (112), and a second lens (114). The module also has a second optical system for delivering an observation beam (66) through the layer and onto a portion (68) of the device and for forming from rays (69) stemming from the observation beam a light pattern (70) indicative of the portion. The information-carrying beam is analyzed in a polarization analysis module into component beams (136, 138) in respective linearly independent polarization states. Converters (144, 146) produce electrical signals (147, 148) indicative of the intensity of the respective component beams; alternatively, the component beams are conveyed for analy…

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