Development of New X-Ray Source Based on Carbon Nanotube Field Emission and Application to the Non Destructive Imaging Technology

In the present work, a new concept of X-ray source was developed. The conventional thermionic tungsten filament tube is commonly available in various fields of application, such as, medical diagnostic and therapy system, microwave amplifier, non-destructive testing (NDT) technology, and so on. However, it has intrinsic problems such as high power consumption, very low X-ray efficiency, and out-gassing problems. Therefore, in the present study a new carbon nanotube (CNT) based X-ray source was developed as a substitute for the conventional one. The new X-ray source consists of three major parts. The CNT electron field emitter was employed as a cathode, a very thin metal mesh as a grid to extract electrons from the CNT, and finally a molybdenum embedded copper target as an anode to accelerate electrons. A supplementary electrostatic focusing lens was employed in the tube to focus the electron beam on the anode target. A detailed description of the tube structure as well as electron beam characteristics is presented in this study. In addition, preliminary X-ray images obtained by using the CNT X-ray tube are presented.