Field Emission X-Ray Devices

Field emission X-ray devices present numerous benefits compared to conventional X-ray sources, such as operating at lower temperatures, delivering enhanced spatial resolution, and consuming less power. These advantages are primarily due to the employment of field emission cathodes, which facilitate efficient electron emission at lower energy unlike thermionic sources. Owing to their superior electron emission properties, robust mechanical strength, and remarkable thermal stability, carbon nanotubes (CNTs) have emerged as a highly promising material for field emission cathodes. This review paper discusses the fundamental principles of X-ray generation, focusing on field emission-based structures. It highlights the superiority of CNTs in terms of stability, emission uniformity, and longevity, compared to conventional thermionic cathodes. The paper also explores advancements in CNT field emission arrays, detailing their integration into X-ray tubes, innovations in device design, and their applications in high-resolution imaging systems and medical diagnostics. Furthermore, the review addresses the challenges of scaling CNT emitters for commercial applications and their potential role in the next generation of X-ray technologies.