GB400314A - Improvements in or relating to advertising or display apparatus - Google Patents

Abstract

400,314. Changing signs. MEKELEK ENGINEERING, Ltd., 57, Victoria Street, and BLACKBURN, C. L., 2, Ryder Street, both in London. May 14, 1932, No. 13870. [Class 3 (i).] In advertising or display apparatus in which colour or other changes occur with change in the relative positions of an observer, a lens, and a screen &c. located approximately in the focus of the lens and having visually distinguishable portions, opaque partitions G are provided extending rearward of the lens B toward the screen &c. C to cut off confused light rays at acute angles of vision. When a plurality of lenses is employed, the partitions may be omitted from some of the lenses, e.g. at the extreme ends. The partitions may be whitened and mirrors may be provided on the inner walls of the casing between the lenses and the screen to give the effect of an extended screen. The screen C may comprise coloured translucent strips backed by a light diffusing sheet D lit by lamps, or may be opaque and be illuminated by light reaching it from the front through the lenses B. In another form, the screen is built up of uniformly or vari-coloured tubular lamps spaced to give a flashing effect, or alternatively an opaque slotted grid in the lens foci has a light source at the rear. The display matter may be in the form of a stencil in front of the lens or lenses, or may comprise moulding on the lens surface or small-angle prisms K, Fig. 5, located in front of the lens B. Fig. 6 shows a modification in which daylight passing through a horizontal screen C reaches the eye after reflection by a mirror L, and the display consists of projections L<1> inclined to the mirror surface. The parts may also be arranged as a daylight sign with the lenses between the mirror and the observer. The lenses may be disposed in both columns and rows. The screen C may be reciprocated or rotated in its own plane, or may be carried on a moving endless band or on a rotating drum. The lenses B may alternatively be moved, or the mirror L, Fig. 6, may be rocked, e.g. by a thermal switch.