Apparatus and method for measuring magnetization of surfaces
US6593739B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 2001 |
| Grant date | Jul 15, 2003 |
| Priority date | — |
| Expiry date | Jun 24, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/0325
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical apparatus and methods for efficiently determining the magnetization of a material at very high optical resolution are disclosed. Individual components of the magnetization may be determined. Components in the plane of the sample surface are imaged by illuminating the material obliquely with substantially parallel light of relatively high power and very well controlled uniformity and polarization, and using light scattered obliquely in a parallel beam in the opposite direction at the same angle as the angle of incidence to record an image. Reversing the illumination and observation directions allows subtraction of the two images and measurement of the magnetization in-plane. A second in-plane component orthogonal to the first, is obtained similarly after reorienting the plane of incidence 90 degrees. The third magnetization component,—perpendicular to the sample surface—, may be obtained using illumination at both angles of incidence and subtracting two images, each recorded when a light-polarization angle of offset from extinction, is reversed. All three components may thereby be imaged without recourse to modulating the sample magnetization as in previous me…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.