On-tool wavefront aberrations measurement system and method
US9395266B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 2014 |
| Grant date | Jul 19, 2016 |
| Priority date | — |
| Expiry date | Mar 26, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B21/125
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An on-tool measurement system and a method for measuring optical system's wavefront (WF) aberrations are disclosed. The on-tool measurement system includes an optical setup comprising a moveable deflection element further comprising a highly transparent region. The deflection element includes a first surface configured to project a first image of at least one object onto a sensor and the highly transparent region includes a second surface configured to project a second image of the at least one object onto the sensor. The on-tool measurement system includes a sensor configured to capture the first and second images and a controller configured to measure differential displacements between the first and second images at each deflection element position and to calculate the optical setup local WF gradients that depend on the measured differential displacements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.