Detection apparatus having an object gradient detection
US6369375B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 21, 1999 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Sep 21, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B21/367
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A detection apparatus includes a differential interference microscope having a light source, an illumination optical system for splitting light from the light source into two polarized components, which are introduced onto an observation object and an imaging optical system for forming an image of the observation object; a device for changing the amount of retardation between the two polarized components; a device for photographing the image of the observation object; and a device for performing a calculation on the image captured by this photographing device. In the detection apparatus, amounts of retardation between the two polarized components are detected to form two differential interference images relative to the observation object in which the amounts of retardation between the polarized components are equal, but signs are different. Image information is extracted from these two differential interference images and thereby the profile of the observation object can be detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.