Four-member gauss objective
US4123144A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1977 |
| Grant date | Oct 31, 1978 |
| Priority date | — |
| Expiry date | May 16, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B9/42
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A four component six lens element Gauss type objective having an aperture ratio of at least 1:2.4 and a field angle of greater than 40.degree. , comprising in the direction of light travel: a first single component positive meniscus concave toward the diaphragm; a second and third cemented doublet meniscus component concave toward the diaphragm, each of the doublet components having planar bond surfaces and a low positive or negative power of refraction; a diaphragm located between said second and third component; and a fourth single component having positive power of refraction with the weaker surface facing the diaphragm; wherein at least two pairs of spherical lens surfaces which are arranged symmetrically with respect to the diaphragm have identical radii of curvature; wherein the ratio of the dispersion values of the first and sixth lens, of the second and fifth lens, and of the third and fourth lens, respectively, in the direction of light travel, are essentially as follows: EQU 0.58 .ltoreq. .nu..sub.1 : .nu..sub.6 .ltoreq. 1.0 EQU 0.8 .ltoreq. .nu..sub.2 : .nu..sub.5 .ltoreq. 0.9 EQU 0.74 .ltoreq. .nu..sub.3 : .ltoreq..sub.4 .ltoreq. 0.8 wherein the refractive indices of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.