the invention comprises a display unit for displaying at least two consecutive images to be viewed by a viewer . the unit comprises , a housing having at least two wall portions defining a cavity therebetween . at least part of one of said wall portions is made of an array of linear lenses having a lenticular front face and a flat rear face . at least one carrier is provided within the cavity . the carrier is able to receive in use a substantially planar display member , and pressure means are provided to urge the display member against the lens when a display member is within the cavity .