Safe laser device for optical sensing applications
US10181701B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2016 |
| Grant date | Jan 15, 2019 |
| Priority date | — |
| Expiry date | Mar 29, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/18391
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention describes a laser device (100) comprising between two and six mesas (120) provided on one semiconductor chip (110), wherein the mesas (120) are electrically connected in parallel. The laser device (100) is adapted such that degradation of at least one mesa (120) results in a decreased laser power emitted by the laser device (100) in a defined solid angle when driven at the defined electrical input power. The laser device (100) is adapted such that eye safety of the laser device (100) is guaranteed during life time of the laser device (100). Eye safety may be guaranteed by designing the semiconductor structure or more general layer structure of mesas (120) of the laser device (100) in a way that degradation of one or more layers of the layer structure results in a reduction of the maximum optical power emitted in a defined solid angle. Alternatively or in addition, the electrical input power supplied to the laser device (100) may be controlled and adapted depending on the emitted optical power such that safety limits are not exceeded. The invention further relates to a laser module and an optical sensor (300) comprising such a laser device (100) and mobile communicatio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.