Detector, imprint apparatus, and article manufacturing method
US8922786B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2012 |
| Grant date | Dec 30, 2014 |
| Priority date | — |
| Expiry date | Jan 24, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34715
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A detector includes an illumination optical system that illuminates a first diffraction grating having a period in each of a first direction and a second direction different from the first direction, and a second diffraction grating having a period in the second direction different from the period of the first diffraction grating in the second direction. A detection optical system detects diffracted light diffracted by the first diffraction grating and the second diffraction grating. The detection optical system includes a photoelectric conversion element and a guide portion arranged on a pupil plane of the detection optical system. The guide portion guides, to the photoelectric conversion element, the light diffracted by the first diffracting grating and the second diffraction grating. The diffracted light diffracted by the second diffraction grating enters a position different from the guide portion on the pupil plane of the detection optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.