Key unit, method for marking key top, and method for manufacturing key unit using the same
US7512229B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 2003 |
| Grant date | Mar 31, 2009 |
| Priority date | — |
| Expiry date | Nov 20, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2009/187
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
As a marking laser beam, a laser beam of wavelength 532 nm obtained by extracting by extracting second higher harmonic of the Nd:YAG laser or a laser beam of wavelength 355 nm obtained by extracting third higher harmonic of the Nd:YAG laser is used on a metal film formed on a plastic key top of a mobile telephone or the like, so that the metal film portion subjected to the beam is completely removed or only the surface portion of the metal film subjected to the beam is removed, thereby forming a planar set of very small concave points. Thus, it is possible to obtain a key unit having a metal film on which a character or symbol is directly marked.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.