Design of a large-format high-resolution streak camera with a planar photocathode

摘要

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 1p/mm and the deflection sensitivity is approximately 64 kV/mm.