GB294723A - Improvements in or relating to apparatus suitable for use as a sign or for other display purposes - Google Patents

Abstract

294,723. Beuttell, A. W. Feb. 15,1927. Signs.-Uniform illumination of an advertisement or other display is obtained by the use of a concave transparent window of sheet glass or the like adapted to receive light rays at a large angle of incidence and reflect them on to the display, thus balancing the loss in intensity of illumination as the distance from the source increases, by the higher percentage of reflection as the angle of incidence increases with the distance from the source. Fig. 2 shows a concave transparent viewing window a reflecting light from the reflector-shaded lamp c towards the screen b which may be of reflecting or diffusing material and may carry or serve as a background to figures, letters, pictures or objects to be displayed, such objects &c. being either reflecting or diffusing as desirable. In some cases parts of the inner surface of the window a may be occupied by light-diffusing or translucent letters &c. out of line with those on the screen b, enabling both sets to be viewed at the same time, or these letters may be silhouetted against a. plain light-diffusing screen b. The reflector-window a may be partly plane and partly concave, the concave portion reflecting on to the part of the display remote from the source. Where the display is to be viewed from both sides two opposed concave reflector-windows may be employed, each carrying letters &c. on their inner surfaces, with or without objects arranged intermediately for display, and also with or without an opaque screen arranged between them to function similarly to the screen b, Fig. 2. In another construction the reflector plates resemble a bi-convex .[ane. the lamp being placed between them on the principal axis and shaded from direct vision. The screens may be open at the ends or may be closed by mirrors or plates carrying letters, thus forming a box casing.