A purification device (1), for the purification of a liquid-crystal mixture, has a flow chamber (2) which has an inlet opening (3) and an outlet opening (4), arranged opposite the inlet opening, in order to be able to introduce the liquid-crystal mixture into the flow chamber (2) and discharge it from the latter, and at least one flow distribution element (5) which is arranged in the flow chamber (2) in the region of the inlet opening (3), and at least one filter element (6) which is arranged in the region of the outlet opening (4), where a length of the flow chamber (2) measured in the flow direction is at least a factor of 2 greater than a greatest internal dimension of the flow chamber (2) transverse to the flow direction.