Method of laser marking a body of material having a thermal conductivity approximately equal to that of glass
US5767483A · kind A · utility
87Cited by
8References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 1, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jul 1, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M3/14
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method of providing a body of material (14), having a thermal conductivity approximately equal to that of glass, with a sub-surface mark. A beam of laser radiation (12) to which the material (14) is substantially opaque is directed to surface of the body, so as to cause beam energy to be aborbed at the surface of the material in an amount sufficient to produce localised stresses within the body (14) at a location spaced from the surface without any detectable change at the surface, the localised stresses thus produced being normally invisible to the naked eye but capable of being rendered visible under polarised light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.