A GATED MICROCHANNEL PLATE SOFT-X-RAY IMAGING-SYSTEM FOR A LASER-PLASMA EXPERIMENT

A picosecond soft X-ray imaging system for a laser plasma experiment w hich is convenient for practical use is developed. The system, based o n a gated microchannel plate (MCP) with four 6-mm-wide stripline catho des is capable of capturing multiframe soft X-ray images at time resol ution of 60-100 ps and spatial resolution of 15 lp/mm. During design a nd construction of the system, emphasis was placed on reliability and operating convenience. The four gating pulses for each stripline were generated by a single avalanche transistor circuit, ensuring a steady time sequence and the same waveform for each pulse. The transmission c haracteristics of the four striplines were adjusted to be identical by monitoring the time domain reflectometry (TDR) of each stripline. The construction of the pulser and striplines in this manner allowed for both timing and sensitivity consistency of the gating for the four str iplines. A pinhole system was equipped in front of the imager with pre cise control and flexible pinhole illumination, making the alignment a nd adjustment of the pinhole array very easy. The system was used in a high-power laser plasma experiment and results were obtained both wit h the pinhole and pinhole grating array.