A radiation detector element which comprises a scintillator laminate for converting X-ray energy incident on said radiation detector to visible light, the scintillator laminate comprising a ceramic scintillator layer and a single crystal scintillator layer and a photodetector for converting the visible light from the scintillator laminate to electrical signals. The single crystal scintillator is interposed in the path of the light scintillations from the ceramic scintillator to the photodetector.

A light transmitting member is disposed between a scintillator element array consisting of a plurality of scintillator elements and a multichannel photodiode including a plurality of photodiode elements. Light transmitting elements of the light transmitting member are formed of a material whose light transmission factor is higher than that of the scintillator elements and which absorbs radiation (X-rays). Absorbed by the scintillator elements and the light transmitting elements, therefore, incident X-rays are prevented from being projected on the photodiode. On the other hand, light emitted from the scintillator elements is transmitted through the light transmitting member with high light transmission factor, and detected by the photodiode. Thus, the detectable quantity of light is large.

An imaging X-ray sensor is composed of a linear array of microscopically small bars of polycrystalline ceramic scintillator material bonded at the bar ends to an integrated circuit photodetector array. The scintillator bars are the basic resolution elements of the detector and are less than 50 microns in width. Each bar produces a flash of light with intensity related to the X-ray flux penetrating the bar. A reflective coating covering five surfaces of the bars isolates each detector element and channels the light into the photodetector bonded to one end of the bar. A method of fabricating the detector array utilizes the machineability and good mechanical strength of scintillators such as rare earth oxides doped with rare earth activators.

A system and method of computer tomography imaging using a cerium-doped lutetium orthosilicate scintillator are provided. The system includes a high frequency electromagnetic energy projection source to project high frequency energy toward an object, such as a patient. A scintillator array having a plurality of cerium-doped lutetium orthosilicate scintillators therein receives the high frequency energy attenuated by the object and emits light energy based on the attenuated energy received. A photodiode array including a plurality of photodiodes is optically-coupled to the scintillator array and configured to detect the light energy and discharge output to a data processing system to produce a visual display. Each scintillator of the scintillator array is formed into a transparent glass ceramic having a high crystalline phase by combing glass-forming compounds in a glass forming system. A method of combining glass-forming compounds to form the cerium-doped lutetium orthosilicate into a transparent glass ceramic is also provided.

A ceramic scintillator material consists of a sintered body of a rare earth oxysulfide phosphor containing Pr as an activator. The sintered body has a texture where coarse grains of irregular polyhedron and slender fine grains are intermixed. The coarse grains have a shape of for instance a dimension (average value) in the range of 50 to 100 .mu.m, the fine grains having a shape of which average short axis is in the range of 2 to 5 .mu.m and average long axis in the range of 5 to 100 .mu.m. An area ratio of the coarse grains to the fine grains is in the range of 10:90 to 60:40. Such a ceramic scintillator material has, in addition to excellent light output (high sensitivity), mechanical strength capable of coping with downsizing of a detector. Furthermore, non-uniformity in sensitivity that causes artifacts can be decreased.