Phase Contrast Imaging using Sub-mJ, Kilohertz Femto-Second Laser produced Cu-K$_{\alpha }$ Source

We present an efficient Cu-K$_{\alpha }$ x-ray source produced by a commercial kilohertz fs laser system. The source has a high x-ray conversion of well over 10$^{-5}$ into K$_{\alpha }$ line emission at 8.05 keV. The micro plasma x-ray source is produced by focusing 260 $\mu $J laser pulses of 130 fs (FWHM) on a moving Cu-wire target. The source has a size of $<$ 10$\mu $m providing sufficient spatial coherence for phase contrast imaging applications. An average x-ray photon flux of $>$ 10$^{9}$ ph/sr/s is achieved in the exposure to record the in-line phase contrast images of test samples. This compact source can be developed into a durable low cost operating system for phase contrast imaging of biological specimens. Detailed characterization of the source and analysis of example exposures will be presented.