A luminescent body of a generic type is known, for example, from DE 42 24 931 A1. The known luminescent body exhibits isotropic conduction of light. Thus, scintillation light formed by incident X-radiation emerges from the luminescent body uniformly in all directions.
Especially in the field of X-ray computer tomography, it is necessary for incident X-radiation to be detected with spatial resolution. To this end, the known luminescent bodies are adhesively bonded onto an electronic detector element, which records the emitted scintillation light.
The luminescent bodies are structured, for example provided with notches, and/or optically isolated from one another by means of collimators in order to suppress lateral propagation of light. This can prevent crosstalk with a neighboring detector element due to lateral propagation of light. Production of the known luminescent body and the provision of a collimator are expensive.
DE 197 15 275 C1 describes a luminescent body with anisotropic conduction of light. A body made of the luminescent substance is in this case provided with optical channels, in which the luminescent light emerges and is delivered along a privileged direction. In practice, it has been found that the luminous efficiencies achievable with such luminescent bodies are not very high.
DE 101 16 803 A1 discloses a radiation transducer in which needle crystals are applied to a substrate by way of evaporation. The needle crystals extend perpendicular to the face of the substrate. The production of such needle crystals is restricted to particular luminescent materials. Such luminescent materials are unsuitable for producing X-ray detectors for X-ray computer tomography.
DE 41 24 875 A1 discloses a radiation transducer screen. The luminescent body is in this case made of a glass ceramic. The luminescent crystals can be produced in a direction extending perpendicular to the detector plane by directional crystallization. This gives rise to anisotropic conduction of light. Unfortunately certain luminescent substances, in particular. luminescent substances for producing detectors for X-ray computer tomography, are incompatible with a glass-ceramic production method.
USPTO Backgrounds
USPTO Backgrounds