The invention relates to the obtainment of magnetic resonance measurement data for the reproduction of an image of an object volume, illustrating the contrast between volume elements (voxels) which differ from one another in the parameter vectors P.sub.i of the magnetic resonance property of the respective inherent substance i. The object volume which is to be imaged is subjected within a stationary magnetic field to a sequence of repetitive blocks of effects, each containing an RF-pulse with a flip angle .alpha.<90.degree. and magnetic field gradients, in order to obtain in each block N.gtoreq.1 location-coded measurement signals and to achieve sufficient intravoxel dephasing, wherein the phase .phi.(k) of the RF-pulse is changed from block to block in accordance with the rule .phi..sub.k-.phi..sub.k-1=.phi.+k*.PHI., where k is the running index of the blocks within the sequence and .phi. is a randomly selected phase angle. In accordance with the invention, for the sequence parameter .PHI. a value .PHI..sub.c is selected, in which the set {S.sub.ij} of the difference values.times..function..PHI..function..PHI. ##EQU00001## is optimized in accordance with a selected criterion K ({S.sub.ij}), where n with 1.ltoreq.n.ltoreq.N is the running index of the measurement signals detected within a respective block, S.sub.n(.PHI.,Q,P.sub.i) or S.sub.n(.PHI.,Q,P.sub.j) is the value of the transversal magnetization of the voxels, which contain the substance i or j, in the condition of dynamic equilibrium at the point in time of the maximum of the nth measurement signal, Q stands for the values of the remaining sequence parameters, and {S.sub.ij} includes all desired pairs of substances i and j.

 
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