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Streak cameras are widely used as ultrafast diagnostic tools in several research fields. With an increase in the complexity of the experiments being conducted, large-format streak cameras with high spatiotemporal resolution are required for wide-band, high-precision spectroscopic recording. This paper presents the design of a high-resolution large-format streak camera with a planar photocathode. To alleviate the effect of field curvature for a large-format photocathode and to improve its spatial resolution, a weak–strong double-focusing lens coupled with a spherical fluorescent screen is used. A high voltage is also used to reduce transit time dispersion in order to improve temporal resolution. Experimental results show that the minimum effective diameter of the planar photocathode is 40 mm, compare to the existing 30 mm photocathode, which can achieve a minimum spatial resolution of 1000 line pairs and a temporal resolution of approximately 4 ps. The dynamic spatial resolution achieved is 20 lp/mm and the deflection sensitivity is approximately 64 kV/mm. [ABSTRACT FROM AUTHOR]

Streak cameras are widely used as ultrafast diagnostic tools in several research fields as the spatiotemporal measurement is of great significance in physics, chemistry, and biomedical research. However, as action objects, electron beams inside streak tubes are easily affected by the surrounding environment, which may lead to deterioration in the performance. In this study, the influence of a geomagnetic field on a streak tube is verified through a simulation. Based on the simulation results, the variation in the image shape due to the geomagnetic field and the overall camera imaging characteristics are analysed theoretically for the first time. The experimental result demonstrates that the imaging characteristics are better after a theoretical analysis is conducted and the final image is adjusted according. We discuss how this analysis can further develop other types of electron optical imaging systems and experiments. [ABSTRACT FROM AUTHOR]