Single- and multiframe gated x-ray images with time resolution as fast as 150 ps are described. These systems are based on the gating of microchannel plates in a stripline configuration. The gating voltage comes from the avalanche breakdown of a reverse biased p–n junction producing high-power voltage pulses as short as 70 ps. Results from single- and four-frame x-ray cameras used on Nova are described.

We report on the response of three scientific charge-coupled devices (CCD), the RCA SID501, the Tektronix TK512M, and the Texas Instruments 4849, to direct electron bombardment. A scanning electron microscope is used to provide a temporally gated, focused electron source of precise energy and current. Both the detection efficiency and the line-spread response of the CCDs have been measured at incident electron energies in the range of 0.3–30 keV. Simple models for the detection process are discussed.

The LLNL optical streak camera is used by the Laser Fusion Program in a wide range of applications. Many of thesf applications require a large recorded dynamic range. Recent work has focused on maximizing the dynamic range of the streak camera recording system.For our streak cameras, image intensifies saturation limits the upper end of the dynamic range, we have developed procedures to set the image intensifier gain such that the system dynamic range is maximized. Specifically, the gain is set Such that a single streak tube photoelectron is recorded with an exposure of about five ti^es the recording system noise. This ensures detection of single photoelectrons while not consuming intensifier or recording system dynamic range through excessive intensifier gain. The optimum intensifier gain iias been determined for twr types of film and for a lens-coupled CCD camera.We have determined that by recording the streak camera image with a CCD camera, the system is shot-noise limited up to th~ onset of image intensifier nonlinearity. When recording on film, the film determines the noise at high exposure levels.There is discussion of the effects of slit width and image intensifier saturation on dynamic range.

Results are presented with a 15-mm-wide gated microchannel plate UV and x-ray detector. The active area is part of a 6-Ω transmission line driven by an electronically generated gate pulse. The microchannel plate is coated with CsI allowing tests with a frequency-quadrupoled, high-repetition-rate 1.05-μm laser. Results showing optical gate widths as short as 100 ps are presented.

To accurately measure pulse amplitude, shape, and relative time histories of optical signals with an optical streak camera, it 1s necessary to correct each recorded Imaqe for spatially-dependent qain nonunlformlty and geometric distortion. Gain nonunlformltles arise from sensitivity variations 1n the streak-tube photocathode, phosphor screen, fmaqe-lntenslfler tube, and 1maqe recordInq system. These nonunfformities may be severe, and have been observed to be on the order of 100* for some ILNL optical streak cameras,. Geometric distortion due to ootlcal couplings, electron-optics, and sweep nonllnearity not only affects pulse position and tlmlnq measurements, but affects Pulse amplitude and shape measurements as well. By using a l.053-um, long-pulse, hiqh-oower laser to generate * spatially and temporally uniform source as Input to the streak camera, the combined effects of flat-field response and geometric distortion can be measured under the norma? dynamic operation of cameras with S-l photocathodes. Additionally, by us-tnq the sane laser system to generate a train of short pulses that can be spatially modulated at the Input of the streak camera, we can effectively create a two-dimensional grid of equally-soaced pulses. This allows a dynamic measurement of the geometric distortion of the streak camera. We win discuss the techniques involved in performing these calibrations, will present some of the measured results for LLNL optical streak cameras, and will discuss software methods to correct for these effects.