We developed multi-channel x-ray monochromatic camera which provides two dimensionally space-resolved monochromatic images for line radiations from tracers impremented in a fusion pellet imploded by intense laser light, evaluate sphericity and temperature distribution of the imploded core plasmas. Use of toroidally bent crystals such as silicon and germanium enables the camera to have variable spectral resolution (5 to 30eV) and 10μm spatial resolutio Described here are the principle of x-ray monochromatic imaging method and its application to imploded plasma diagnostic. Obtained images by the camera are also shown.

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We have developed a multi-channel, multi-imaging x-ray streak camera (McMIXS) technique to measure two-dimensional electron-temperature distributions with a high temporal resolution by adding a multi-channel spectrum selection capability to a multi-imaging x-ray streak camera (MIXS) technique, and applied it to direct-drive implosion experiments with partially-coherent light at Gekko-XII laser facility. It was found that electron-temperature distributions in the laser-imploded core plasmas of ICF targets had low-mode nonuniform structures changing with a temporal scale of 20 ps, and the abrupt drop of the electron-temperature appeared in the deceleration phase. We have compared temporal profiles of the experimentally observed x-ray intensity and electron-temperature with those predicted by a one-dimensional hydrodynamic code "ILESTA" to investigate the hot spark heating in the core plasmas.

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We present prinsiples of the time-resolved shodowgraph method using laser-produced x rays which illuminatefrom backwards of targets. Time-resolved x-ray detectors are used to measure the probe x-rays so that we obtained the characteristics of the target as a shadowgraphed image. We also describe expamles of experimental results about hydrodynamic instabilities in laser plasmas, which were obtained from this method.

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In the field of denntal diagnostic equipment, an X-ray image acquisition technique using a Charge Coupled Device (CCD) has recently been deviced. Compared with the conventional method using X-ray films, this technique has merits of dose reduction and high-speed imaging. An X-ray CCD sensor has been developed with the following features ; (1) Rapid image acquisition saves X-ray processing time, allowing more communication time with the patient. (2) Reduced X-ray exposure time immproves the safety of the dentist and patient. (3) Digital image processing secures higher diagnostic accuracy and reliability. (4) Using electronic media for imgae storage makes possible higher efficiency in medical work.

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We have designed and developed a soft x-ray laser probe system to diagnose a laser produced plasma. In order to measure the electron density profile of overdense (10^<21>〜10^<22>cm^<-3>) plasmas with grid imaging refractometry (GIR), we tried preliminary examination of probing underdense (8×10^<20>cm^<-3>) plasmas. We discuss the problems to realize the overdense plasma density measurements taking account of the exponential results. We also report measurement of laser initial imprint on targets with this system.

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Recently, the CPA (charped pulse amplification) method was invented and opened up a new field in the high power laser technology. As the results of the invention of CPA, high intensity ultra-short pulse laser became available and the laser power increased by more than one thousand times in recent several years. By this development of the laser technology, a new ignition method in laser fusion became in reality, which is so called 'fast ignitor'. Furthermore, the peta watt laser will generate relativistic plasmas which will be new high energy particle and radiation sources.

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