Development of a small X‐ray source using an ultraviolet laser and pyroelectric crystal

Abstract

We investigate a miniaturized X‐ray source using an ultraviolet (UV) laser and a pyroelectric crystal and discuss potential applications in medicine. The UV laser is the fourth harmonic of a Nd:YAG laser with a wavelength of 266 nm, repetition rate of 10 Hz, and pulse energy of 40 mJ. The pyroelectric crystal is a LiNbO3 cylinder of diameter 10 mm and length 6 mm. The prototype X‐ray source we fabricated is an aluminum parallelepiped of dimensions 3 × 3 × 5 cm. The X‐ray count rate of the X‐ray source is maximized at approximately 1,400 cps for UV laser irradiation of approximately 5 min. After 30 min of irradiation by the UV laser, the temperature of the pyroelectric crystal rose from 295 K to 312 K. The principles of X‐ray generation ensure that X‐ray sources using UV lasers and pyroelectric crystals offer ample opportunity for miniaturization. We believe the X‐ray source developed in this work is suitable for medical applications, although further study is needed to address points such as increasing the X‐ray count rate and adjusting the temperature of the pyroelectric crystal.

Observation of X-rays during heating a pyroelectric crystal by an infrared laser

“…At the same time, the use of laser radiation [17][18][19] makes it possible to more accurately control the power supplied to the pyroelectric sample during heating and makes it possible to control the duration of irradiation, providing the possibility of both continuous heating and short pulse exposure. To date, prototypes of X-ray sources have been proposed, in which lithium niobate crystals (LiNbO3), placed in a vacuum, were heated with blue (470 nm) [20] or ultraviolet (266 nm) [21] lasers.…”