Double source plane strong lensing (DSPL) systems offer a robust, independent probe of cosmological parameters. The Chinese Space Station Survey Telescope (CSST) is expected to discover hundreds of DSPLs, yet the survey modes and system configurations that best enable cosmological inference remain uncertain. To investigate the impact of varying signal-to-noise ratios and Einstein radius ratios of DSPLs (denoted as β−1 parameters) on cosmographic inference under different CSST survey modes (Wide Field (WF), Deep Field (DF), and Ultra-Deep Field (UDF)), we simulate and model mock lenses with singular isothermal ellipsoid mass profiles and Sérsic sources whose image properties are tailored to CSST specifications. Assuming a flat wCDM universe with fiducial values Ωm = 0.30966 and w = –1, and uniform priors of Ωm ∈ [0, 1] and w ∈ [–2, –1/3), we find that the constraining power on cosmological parameters for a given DSPL system significantly increases with survey depth. For a representative DSPL system with two prominent arcs and a moderate β−1 = 1.17, the constraints on (w, Ωm) improve from () in the WF to () in the UDF. Furthermore, we find that systems with smaller β values yield tighter cosmographic constraints. We conclude that DSPL systems identified in UDF observations, particularly those with small β, are the most promising candidates for early-stage cosmological studies with CSST.

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