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 100 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 S ij = n = 1 N .times. [
S n .function. ( .PHI. , Q , P i ) - S n .function. ( .PHI.
, Q , P j ) ] 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.