| 摘要 |
A phosphor consists of yttrium oxide activated with trivalent europium oxide. The concentration of the europium oxide in the yttrium oxide amounts to between 3 and 8, preferably 4, mol. per cent. The phosphor can be prepared by mixing yttrium oxide, or compounds which produce yttrium oxide on being heated, with trivalent europium oxide or compounds which produce trivalent europium oxide on being heated, and firing the mixture in a closed vessel or in a stream of forming gas consisting of 20% by volume of hydrogen and 80% by volume of nitrogen at a temperature exceeding 1500 DEG C., preferably between 1600 DEG C. and 1650 DEG C. In a particular example yttrium carbonate is mixed with trivalent europium oxide and fired four times for one hour in a stream of forming gas at about 1630 DEG C. In a modification europium carbonate can be used. A particular phosphor referred to is Y2O3.0.04Eu2O3. When energized by the mercury resonance line 253.7 mm the #qmission spectrum shows a narrow-band spectrum in the range from 590 mm to 710 mm with a strong maximum at 615 mm . |
