Back to results
US 8,012,896 B2Granted
Optical glass, preform for precision press molding, method for manufacturing preform for precision press molding, optical element, and method for manufacturing optical element
AssigneeHoya Corporation
InventorYasuhiro Fujiwara
Life of this patent
Estimating the term…
Abstract
The present invention relates to an optical glass having optical constants in the form of a refractive index nd of 1.70 or higher and an Abbé number nud of 50 or higher, a preform for precision press molding comprised of this glass, an optical element comprised of this glass, and methods for manufacturing the preform and the optical element.
Claims38
An optical glass having a refractive index nd of 1.70 or higher and an Abbé number nud of 50 or higher, comprising, denoted as molar percentages:
- B2O3
- 40 to 75 percent,
- SiO2
- greater than 0 percent but not exceeding 15 percent,
- Li2O
- 1 to 10 percent,
- ZnO
- 0 to 15 percent,
- La2O3
- 5 to 22 percent,
- Gd2O3
- 3 to 20 percent,
- Y2O3
- greater than or equal to 0 percent but less than 1 percent,
- ZrO2
- 0 to 10 percent,
- MgO
- 0 to 5 percent,
- F
- 5 percent or less,
- CaO
- 0 to 5 percent, and
- SrO
- 0 to 5 percent.
21 more elements
An optical glass having a refractive index nd of 1.70 or higher and an Abbé number nud of 50 or higher, comprising, denoted as molar percentages:
- B2O3
- 40 to 75 percent,
- SiO2
- greater than 0 percent but not exceeding 15 percent,
- Li2O
- 1 to 10 percent,
- ZnO
- 0 to 15 percent,
- La2O3
- 5 to 22 percent,
- Gd2O3
- 3 to 20 percent,
- ZrO2
- greater than 5 percent but not exceeding 10 percent,
- MgO
- 0 to 5 percent,
- F
- 5 percent or less,
- CaO
- 0 to 5 percent, and
- SrO
- 0 to 5 percent.
19 more elements
Dependencies are inferred from the claim text.