基于碳纳米管冷阴极的微焦点X射线源及其应用

Micro-focus X-Ray Source Based on Carbon Nanotube Cold Cathode and Its Application

碳纳米管(CNTs)场致发射源作为一种新的冷阴极电子发射源,能克服传统热阴极的缺点,基于CNTs冷阴极的微焦点X射线源的扫描成像系统可实现脉冲式发射、高速拍照、低剂量的特点,是一种可代替热阴极材料作为X射线管的核心阴极材料,目前在生物医疗、无损检测和科学研究等领域已经展现了巨大的应用价值,但在技术实现上CNTs阴极的可靠性、工作寿命和电流发射密度等仍存在瓶颈问题。本文回顾了微焦点X射线源的发展历史并介绍了CNTs冷阴极的制备工艺,展示了目前CNTs冷阴极的微焦点X射线源在工业和医疗领域取得的巨大成功,并结合实际的研究情况,探讨其发展中遇到的问题和未来的发展方向。

As a new cold cathode electron source,carbon nanotube(CNT)field emission source can overcome the shortcomings of traditional hot cathodes.The scanning imaging system based on CNT cold cathode micro-focus X-ray source can realize the characteristics of pulsed emission,high-speed photography and low dose.CNT is considered a kind of core cathode material that can replace hot cathode material in X-ray tubes.At present,CNT has shown great application values in the fields of biomedicine,non-destructive testing and scientific research,but there are still bottlenecks in the reliability,working life and current emission density of CNT cathodes in technical realization.The development history of micro-focus X-ray sources is reviewed and the preparation process of CNT cold cathodes is introduced.The great successes achieved by CNT cold cathode micro-focus X-ray sources in industrial and medical fields are shown.The problems encountered in the development and the future development direction are discussed according to actual research situation.