Luminescent ceramic plates
US4849639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1986 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Aug 15, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ceramic plate capable of luminescing under electron X-ray or other ionizing radiation comprises a fine powder bound in water glass such as sodium or potassium hydroxy silicates, or sodium or potassium borates. The powder is typically less than 50 .mu.m mean particle size e.g. 10 .mu.m size. Powder material includes: calcium borate, yttrium aluminate, zinc yttrium silicate, calcium silicate, germanate, Magnesium borate, Barium borate, strontium borate. Dopant materials may be Tb, Tm, Ce, Eu, Pr, Yb, Mn, Cu, Ag, Pb added in amounts up to 15% weight or more. The plate is formed by mixing powder and water glass into a dough. The dough is pressed in a mould to remove excess water glass and fired at about 950.degree. C. for about 8 hours. Alternatively excess water is used when mixing powder and water glass. This excess water is allowed to evaporate while the plate is in a mould prior to pressing and firing. The plate may be used as a cathode ray tube face plate, the detector in an X-ray thermoluminescent system, or an X-ray scintillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.