Improvements in or relating to infra-red phosphors.

摘要

An infra red emissive phosphor consists of chromium activated cerium manganese alumnate having a hexagonal crystal structure and represented by the general formula:
<CHEM>
where x is from 0.3 to 3.0, to y is from 0 01 to 2.0, z is from 0 001 to 0.3 and R is manganese, in which up to 95 atomic percent of the manganese may be replaced by an equivalent amount of zinc or magnesium or both.