Lead glass composition series for gradient glasses
US5459613A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 24, 1993 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | Nov 24, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B3/0087
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A fused glass block having an axial gradient index of refraction profile between two opposed parallel surfaces, with a change in refractive index from one of the surfaces to the other ranging from about 0.04 to 0.47, is provided. The fused glass block has a change in thermal expansion coefficient from one of the surfaces to the other of less than about 3.times.10.sup.-7 .degree.C..sup.-1, has essentially no strain or birefringence therein, and has a smoothly varying refractive index profile from one of the surfaces to the other. The fused glass block is prepared from at least two pre-selected compositions of a lead-silicate glass series that has been discovered to provide the requisite properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.