Method and system for optical three dimensional topography measurement
US11287248B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 2020 |
| Grant date | Mar 29, 2022 |
| Priority date | — |
| Expiry date | Mar 2, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2210/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
For three-dimensional topography measurement of a surface of an object patterned illumination is projected on the surface through an objective. A relative movement between the object and the objective is carried out, and plural images of the surface are recorded through the objective by a detector. The direction of the relative movement includes an oblique angle with an optical axis of the objective. Height information for a given position on the surface is derived from a variation of the intensity recorded from the respective position. Also, patterned illumination and uniform illumination may be projected alternatingly on the surface, while images of the surface are recorded during a relative movement of the object and the objective along an optical axis of the objective. Uniform illumination is used for obtaining height information for specular structures on the surface, patterned illumination is used for obtaining height information on other parts of the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.