Phase contrast microscope
US5751475A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1994 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Dec 16, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/52
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A phase contrast microscope including an illuminating optical system, a ring slit arranged at a pupil of the illuminating optical system, an imaging optical system, and a phase plate arranged at a pupil of the imaging optical system which is conjugate with the pupil of the illuminating optical system with respect to a specimen plane on which a specimen under inspection is placed. The phase plate is formed by a liquid crystal and a pair of transparent ring-shaped electrodes arranged on both sides of the liquid crystal. A voltage applied across the liquid crystal via the electrodes is changed such that a phase difference introduced by the phase plate is set to .+-..pi./2 to obtain a dark contrast image and a bright contrast image. A difference between these dark and bright contrast images is derived to obtain a phase contrast image having high contrast and resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.