OPTICAL CERAMIC SCINTILLATORS FOR DIGITAL RADIOGRAPHY

本项目的目标是开发一种基于活性透明光学陶瓷技术的用于数字化牙科X射线摄影的上级X射线探测器。 进展已经远远超过了我们的第一阶段目标，产生了一个完全致密的TOC，其光输出（通过CCD测量）与CsI：Tl相当。 我们还开发了一种用于像素化这种材料的激光技术，在12 1 p/mm处实现了20%的MTF，分辨率是Gd 2 O 2S：Tb屏幕的两倍。 第二阶段将解决三个关键领域：我们将通过定义最佳陶瓷成分和处理来最大限度地提高光输出，并特别关注开发商业上可行的合成技术。 我们将改进像素化工艺，以便蚀刻出由宽度不超过2.5微米且纵横比至少为50：1的凹槽分隔的50微米正方形像素的阵列，以便达到至少90%的屏幕填充因子，并开发出以适合于大规模生产的速度实现这一点的系统。 我们将在真实的生活条件下制造、测试和评估原型装置。 这些成果将为二期工业开发奠定坚实的基础。拟定商业应用：由于目前可用的X射线荧光屏不能提供必要的空间分辨率，医疗射线照相术一直无法挖掘数字技术的全部潜力，用于数据采集和处理。开发一种能够满足这一需求的材料将彻底改变放射技术，并大大提高其诊断能力。 直接市场不仅包括整个牙科社区，还包括其他放射成像，如断层扫描，并可能扩展到目前使用的几乎每一台X光机。

The objective of this program is to develop a superior X-ray detector for digital dental radiography, based on the technology of activated transparent optical ceramics. Progress has far exceeded our Phase I goals, producing a fully dense TOC whose light output as measured by CCDs is on a par with CsI:Tl. We have also developed a laser technique for pixelating this material, achieving an MTF at 12 1p/mm of 20%, a resolution twice as good as a Gd2O2S:Tb screen. Phase II will address three critical areas: We will maximize the light output by defining the optimal ceramic composition and treatment, with special attention to developing a commercially viable synthesis technique. We will improve the pixelization process so as to etch an array of 50 microm square pixels separated by grooves no more than 2.5 microm wide and an aspect ratio of at least 50:1, so as to reach a screen fill factor of at least 90%, and develop a system for achieving this at a speed appropriate for large-scale production. And we will fabricate, test, and evaluate prototype units under real life conditions. These results will form a solid foundation for Phase II industrial exploitation. PROPOSED COMMERCIAL APPLICATION: Because currently available X-ray phosphor screens cannot provide the necessary spatial resolution, medical radiography has been unable to tap the full potential of digital techniques for data acquisition and processing. The development of a material that can fill this need will revolutionize radiological techniques and greatly enhance their diagnostic power. The immediate market includes not only the entire dental community, but also other radiographic imaging such as tomography, and potentially extends to virtually every X-ray machine now in use.