Water-immersed high precision laser focus spot size measurement apparatus
US11156453B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 2020 |
| Grant date | Oct 26, 2021 |
| Priority date | — |
| Expiry date | Jun 19, 2040 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2009/00855
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A measurement apparatus for measuring a laser focus spot size, which includes a two-dimensional image detector and an imaging system which forms a magnified image of a focus spot located an object plane onto the image detector. The imaging system includes at least an objective lens. A sealed liquid container is secured over a part of the objective lens such as the optical surface of the objective lens is immersed in the liquid (e.g. water) within the container. The liquid container has a window through which the laser beam enters. An image processing method is also disclosed which processes the image obtained by the image detector to obtain the focus spot size while implementing an algorithm that corrects for the effect of ambient vibration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.