Method for measuring the viscosity of a material
US5186040A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1991 |
| Grant date | Feb 16, 1993 |
| Priority date | — |
| Expiry date | Nov 27, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2203/0071
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for measuring the viscosity of a material consists in forming an array of parallel strips of material for constituting a diffraction grating; illuminating the array with a monochromatic light beam which produces a diffraction grating comprised of a main light spot (5) and of a plurality of adjacent diffraction spots, the envelope of which exhibits a major lobe (LO) including the main spot (5) and minor lobes (L1, L2); subjecting the array to a thermal process consisting in rapidly heating it at a predetermined temperature (T) and maintaining it at such temperature; selecting the brightest spot (6) among those of the first lobe (L1) and measuring the evolution of its light intensity (HL1) during the thermal process; determining the time interval elapsing until the first passage by a minimum intensity value (HL1b) of the spot (6); and deducting therefrom the value (.nu.) of the viscosity of the material constituting the array by the formula 1/.nu.=.alpha.d.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.