A planar texture of a cholesteric liquid crystal is submitted to a uniaxial steplike strain parallel to the helical axis. Using a time-resolved optical Bragg-scattering technique, we measure the average pitch of the texture (and its dispersion) versus time. We observe a nonuniform hydroelastic dilation, which relaxes to the uniform-strain equilibrium state through a permeative flow.

• Received 4 June 1984

DOI:https://doi.org/10.1103/PhysRevLett.53.2246