The design and construction of a mass spectrograph, for the diagnostics of fast pulsed sources, is described. It is intended particularly for measurements on laser generated plasma. The special features of the instrument are a broad energy passband (Emax/Emin=5) and simultaneous energy independent mass‐focusing for a mass range of (m/z)max/(m/z)min=4. The resolutions of the mass and energy spectra, respectively, are (m/&Dgr;m) =30 and &Dgr;&egr;/&egr;=0.01. A theoretical analysis of the ion‐optics is presented together with test results.