Dark field illumination apparatus for epi-illumination system
US4626079A · kind A · utility
29Cited by
4References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 9, 1985 |
| Grant date | Dec 2, 1986 |
| Priority date | — |
| Expiry date | Apr 9, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B21/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In dark field illumination apparatus for epi-illumination system, in order to attain the above and other objects, the present invention provides an annular light beam which is coaxial with the optical axis of the objective lens and is supplied along an optical path formed surrounding the objective lens. An annular condenser member is arranged near the object side end of the objective lens in such manner that the beam reaches the object surface while being concentrated in the direction toward the optical axis by the condenser member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.