| 摘要 |
An electroluminescent device for use with X-rays as described in the parent Specification has incorporated in the phosphor-containing ceramic layer and/or in a further ceramic layer between the phosphor-containing layer and one of the electrodes a proportion, e.g. up to 50% by weight, of an oxide or other compound of a heavy metal of atomic weight greater than 90 and having a high absorption for X-rays. Suitable compounds are thorium oxide, barium oxide, luminescent calcium tungstate or a phosphor of thorium phosphate. A further compound which fluoresces under X-ray bombardment may be included. Gold can be added in the proportion by weight of between 0.0001 and 0.01%. Specifications 827,967 and 1,003,706 also are referred to. |
