| 摘要 |
PURPOSE:To form a detector of low noises, less difference in output drops and anisotropy, and uniform characteristics by providing a light scattering layer in a passage conducting the light which a scintillator consisting of a layer of phosphor particles emits by radiations to a photodetecting part. CONSTITUTION:A silicon-photodiode 3 is disposed in the bottom part of a case 6 by a material shielding radiations such as, brass or lead, and the inside surface of the case 6 forms a light reflection surface of aluminum. A phosphor particle layer 2 of about 2mm. thickness is disposed on the photodiode 3, and a light scattering layer 4 is formed on the photodiode 3 side. The layer 4 is formed by thinly coating a soln. prepd. by mixing Al2O3 of 3mum average grain sizes with an aq. polyvinyl alcohol soln. The case 6 is covered by a cap 5 consisting of a thin film of aluminum. X rays are made incident to the detector from the direction of an arrow 1, and are absorbed in the layer 2 which emits light. The greater part of the light reflected on each inside surface passes through the layer 4 and arrives at the photodiode 3, by which it is photoelectrically converted. Thereby, the product of the simple construction, less noises, superior characteristics and less variance is obtained.
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