Phase retardance inspection instrument
US8130378B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 2009 |
| Grant date | Mar 6, 2012 |
| Priority date | — |
| Expiry date | May 24, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/216
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A phase retardance inspection instrument, comprising: a light source module for generating a single-wavelength light beam; a circularly polarized light generating module, comprising a polarizer and a first phase retarder, for receiving the single-wavelength light beam as it is guided to pass through the polarizer and the first phase retarder in order; and a detecting module, comprising a second phase retarder, a polarizing beam splitter, a first image sensor and a second image sensor, for receiving and guiding a circularly polarized light beam to travel through the second phase retarder and the polarizing beam splitter in order after it passes through a substrate under inspection, wherein the polarizing beam splitter splits an elliptically polarized light beam into intensity vector components of a left-hand circularly polarized light beam and a right-hand circularly polarized light beam, which are to be emitted into the first image sensor and the second image sensor, respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.