Cold Cathode Flat Panel X-ray Source for Talbot–Lau Grating Interferometer using Zinc Oxide Nanowire Field Emitter Arrays and Periodic Microstructured Anode

The X-ray phase contrast imaging using a Talbot–Lau grating interferometer (GI) can achieve high resolution of low-contrast objects such as soft tissues. The periodic microstructured X-ray source is the key to achieving this technology. We have prepared a vacuum-encapsulated cold cathode periodic microstructured flat-panel X-ray source (FPXS) using zinc oxide (ZnO) nanowire field emitter arrays and microarrays of a Mo thin film transmission target. The device has an operating voltage of 40 kV and a current of 684 μA. A radiation dose rate of 428 μGy/s was measured at a distance of 10 cm from the periodic microstructured FPXS. The X-ray emission distribution is characterized by optical images and radiochromic film, and the localized X-ray emission was confirmed. The X-ray imaging capability was validated by using projection imaging. Our device has potential applications in Talbot–Lau GI phase-contrast imaging.