Claims
- 1. A phosphor which emits light by the excitation of X-rays, and has a composition represented by the formula:
- M.sub.y Ln.sub.1-x-(2/3)y DO.sub.4 :xR.sup.3+
- where:
- M is Cd,
- Ln is at least one rare earth element selected from the group consisting of Y, Gd and La,
- D is Ta, or Ta and Nb,
- R is an activator metal of Tm,
- y is a value in the range of 1.times.10.sup.-5 .ltoreq.y.ltoreq.6.times.10.sup.-1
- x is a value in the range of 0.ltoreq.x.ltoreq.0.05,
- said phosphor being obtained by a process comprising admixing an oxide of Ln in an amount corresponding to 1-x-(2/3)y parts by mol of Ln, an oxide of D in an amount corresponding to one part by mol of D, an oxide of R in an amount corresponding to x parts by mol of R and a carbonate of M in an amount corresponding to y parts by mol of M to prepare an admixture, and
- firing said admixture at a temperature sufficient to provide a phosphor having said composition and
- wherein said phosphor exhibits a smaller afterglow than the same phosphors absent M."
Priority Claims (2)
Number |
Date |
Country |
Kind |
60-106636 |
May 1985 |
JPX |
|
60-198052 |
Sep 1985 |
JPX |
|
Parent Case Info
This application is a continuation, of now abandoned application Ser. No. 219,792, filed Jul. 14, 1988, now abandoned; which in turn is a continuation of now abandoned Ser. No. 823,299, filed Jan. 28, 1986.
US Referenced Citations (5)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0011909 |
Jun 1980 |
EPX |
58-22063 |
May 1983 |
JPX |
Continuations (2)
|
Number |
Date |
Country |
Parent |
219792 |
Jul 1988 |
|
Parent |
823299 |
Jan 1986 |
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