Radiation detecting apparatus, scintillator panel, radiation detecting system, and method for producing scintillator layer

1. A radiation detecting apparatus comprising:

a sensor panel that has a substrate, and has a plurality of pixels each of which has a photoelectric conversion element for converting light into an electric signal, arranged on the substrate; and

a scintillator layer arranged over the pixels, wherein the scintillator layer has a columnar crystal structure including a plurality of columnar crystals, and the scintillator layer contains cesium iodide as a main ingredient and thallium as an activator such that a concentration of the thallium in a peripheral area of the scintillator layer is higher than a concentration of the thallium in a central area of the scintillator layer, and such that the concentration of the thallium in the peripheral area of the scintillator layer is 1.0 mol % or more with respect to the concentration of cesium iodide, and the concentration of the thallium in a central part of the scintillator is 0.5 mol % or more but 1.5 mol % or less with respect to the concentration of cesium iodide; and

a metal layer covering the scintillator layer.

2. The radiation detecting apparatus according to claim 1 , wherein the average concentration of the activator in the outside of the region in the scintillator layer, which faces a region having the pixels formed therein, is higher than the average concentration in the region which faces the region having the pixels formed therein.

3. The radiation detecting apparatus according to claim 1 , wherein the concentration of the activator isotropically increases from the central part in a plane of the scintillator layer to the peripheral area.

4. The radiation detecting apparatus according to claim 1 , wherein the concentration of the activator in the peripheral area of the scintillator layer is higher than the concentration of the activator in all other areas of the scintillator layer.

5. The radiation detecting apparatus according to claim 1 , wherein the scintillator layer is arranged on the substrate to compose a scintillator panel, and the scintillator panel is laminated to the sensor panel.

6. A radiation detecting system comprising:

the radiation detecting apparatus according to claim 1 ;

a signal processing unit for processing a signal sent from the radiation detecting apparatus;

a recording unit for recording the signal sent from the signal processing unit;

a display unit for displaying the signal sent from the signal processing unit;

a transfer processing unit for transferring the signal sent from the signal processing unit; and

a radiation source for generating the radiation.