Laser material processing system
US8563893B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 2006 |
| Grant date | Oct 22, 2013 |
| Priority date | — |
| Expiry date | Oct 30, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/50
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A laser processing apparatus comprises a converging lens 31 for converging processing laser light and rangefinding laser light L2 toward a wafer 1, an actuator for actuating the lens 31, a shaping optical system 49 for adding astigmatism to reflected light L3 of the rangefinding laser light, a quadrant photodiode 42 for receiving the reflected light L3 and outputting voltage values corresponding to its light quantities, and a controller for regulating the actuator, and positions a converging point P2 of the rangefinding laser light L2 between a focal point P0 of the lens and the lens 31, so as to make it possible to form a modified region at a position deeper from the front face 3, thereby suppressing adverse effects due to the reflected light L3. The control is based on an arithmetic value subjected to a division by a sum of the voltage values, so as to prevent the arithmetic value from being changed by the quantity of reflected light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.