Polarizing optical system
US5969861A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1996 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Aug 1, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C17/3417
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A polarizing optical system comprising: at least, polarizing characteristic imparting means for imparting a polarizing characteristic to light emitted from a light source; analyzer means for converting the polarizing characteristic into light intensity information; and output means for outputting the light intensity information; at least one element constituting the polarizing characteristic imparting means comprising an optical glass having a photoelastic constant C in the range of substantially zero with respect to a wavelength range of 0.4 .mu.m to 3.0 .mu.m. The optical glass has a photoelastic constant C in the range of -0.8 to +0.8 (10.sup.-8 cm.sup.2 /N) with respect to a wavelength range of 0.4 .mu.m to 3.0 .mu.m, and has the following composition when represented in terms of wt.% of oxides: PA1 SiO.sub.2 : 17.0-27.0% (35.5-57.0 mol %) PA1 Li.sub.2 O+Na.sub.2 O+K.sub.2 O: 0.5-5.0% (0.7-20.0 mol %) PA1 PbO: 72.0-75.0% (39.1-45.0 mol %) PA1 As.sub.2 O.sub.3 +Sb.sub.2 O.sub.3 : 0-3.0% (0.0-2.0 mol %) The above-mentioned optical glass for polarizing optical system causes substantially no optical path difference based on an optical anisotropy, even when a mechanical external str…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.