Laser-induced Plasma X-ray Source and Its Applications. Soft X-ray Imaging Microscope with a Laser Produced Plasma Source

We constructed a soft X-ray imaging microscope on a laboratory scale by using a laser produced plasma source. Two different soft X-rays (wavelength: 3.2 nm and 5.2 nm) were obtained by using a Nd-YAG laser with a power of 1.2 J and a pulse width of 8 ns. Wolter mirrors were used as a condenser and an objective. A back-illuminated CCD camera was introduced as an X-ray imaging detector. Spatial resolution was estimated to be about 60 nm with a transmission grating object. An X-ray micrograph of a stoma at epidermis of vincia faba L. was obtained. A human red blood cell in a solution was also observed and it showed that the soft X-ray microscope is available for living specimens in a wet state.