The invention relates to a frame for a luminescent screen, comprising frame elements with a closed contour, a circular crown, and frame members consisting of profiles, the frame elements being substantially parallel to each other, the circular crown being concentric in relation to one of the frame elements, and the cap of a bulb being couplable and insertable into the circular crown. The frame elements and the circular crown are interconnected and in contact with each other by means of the frame members, and the frame elements, the circular crown, and the frame members are intercoupled by means of coupling means, said coupling means comprising a first plurality of receiving elements arranged in the frame elements and oriented towards the inside thereof, a second plurality of receiving elements arranged in the crown and oriented towards the outside thereof, and a plurality of projecting elements in the frame members, in such a way that the projecting elements are suitable for inserting and fitting into the receiving elements of the frame elements and the crown.