The performance response of an electronic subnanosecond streak camera to a spatially distributed optical signal varies significantly with the image location on output screen. The variations are due mainly to the combined effects of (1) electron-optics aberrations, (2) camera sweep ramps and gating waveform imperfections, (3) photocathode and phosphor quantum efficiency nonuniformities, and (4) excessive incident intensity or power. Consequently, a dynamic full-scale characterization of the streak camera is necessary for achieving a better measurement accuracy, relative or absolute. To meet this need, we are developing a simple yet versatile technique for characterizing the large-format image-converter-tube based streak cameras that are routinely used as the prime diagnostic instruments at the nuclear test site in Nevada. A mode-locked pulsed dye laser routing through beam splitters and mirrors provides the repetitive light source of multiple pulses with known intensities and inter-pulse timing for illumination along the streak sweep axis. Meanwhile, a bar-chart test pattern at the input slit intercepting an expanded form of the light source, or a bundle of equal-length fibers fanning out into a linear line array replacing the slit, distributes the illumination along the axis perpendicular to the sweep. In one single shot, this technique enables an accurate and detailed mapping of the key performance parametes of a large-format streak camera. The obtainable parameters include quantitative temporal and spatial resolutions, descriptive dynamic range, two-dimensional sweep nonlinearity, and intensity or power dependent distortions. Experimental setup is described. Sample test data, digitization plots, and computer analysis results are presented. (ERA citation 11:001268)
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