Phosphate optical glass with positive anomalous partial dispersion
Abstract
Abstract NOVEL OPTICAL GLASSES ARE DISCLOSED WHICH POSSESS A POSITIVE ANOMALOUS PARTIAL DISPERSION AND WHICH ARE RESISTANT TO CHEMICAL INFLUENCES, FOR EXAMPLE FROM THE ATMOSPHERE, TO SUCH A DEGREE THAT LENSES MANUFACTURED FROM THESE GLASSES CAN BE EMPLOYED AS FRONT LENSES IN OPTICAL SYSTEMS, SUCH AS PHOTOGRAPHIC OBJECTIVES,ACCORDING TO TO THE INVENTION THE GLASSES ARE MELTED FROM A BATCH COMPOSITION CONSISTING ESSENTILALLY OF: 5-20% BY WEIGHT OF THE METAPHOSPHATES OF THE ALKALINE ELEMENTS; 50-75% BY WEIGHT OF A CONSTITUENT SELECTED FROM A GROUP CONSISTING OF THE METAPHOSPHATES OF THE ALKALINE EARTH ELEMENTS MAGNESIUM, CALCIUM, STRONTIUM AND BARIUM; 2-15% BY WEIGHT OF TITANIUM DIOXIDE; AND 2-15% OF THE OXIDE OF BERYLLIUM.
Inventors
- 👤 Heinz Bromer
- 👤 Kreis Wetzlar
- 👤 Norbert Meinert
- 👤 Johann Spincic
Bibliographic Details
Claims Analysis
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