In this paper we describe the development of a novel high‐resolution line‐imaging laser‐Doppler velocimeter to investigate the hydrodynamic response of planar solid targets to the irradiation with intense light ion beams. It is demonstrated that a detailed analysis of the target velocity history can be used to derive equation of state data and to determine ion ranges in hot dense plasmas. To measure the central temperature in sub‐range targets a Kα‐absorption spectrometer is presented which uses a laser produced backlighter in the soft x‐ray regime to transmit radiation through the ion beam heated target.