Method and apparatus for discrete tomography
US6459758B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 1998 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Aug 21, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2223/419
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Discrete tomographic apparatus comprises an electron microscope for irradiating a sample comprising an atomic lattice structure. Line count data is obtained for the main directions of a cross section of the sample. A non-linear programming algorithm is applied to obtain probabilities of occupancy of lattice sites by atoms of the sample. The non-linear programming algorithm comprises an iterative application of the expectation/maximization algorithm upper bounded by the constraint that each variable is valued at less than or equal to one. Once the algorithm is iteratively applied a phantom image of the cross section of the sample is generated. The cross sectional area may be less than one thousand atoms by one thousand atoms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.