Patent ID: 7273308
Filing Date: 2007-09-25
Classification: G02B,Y10S

Abstract:
1. An illuminating unit for use in an internally illuminated sign device for displaying an indicia pattern indicative of certain fixed information within at least one indicia area, the illuminating unit comprising a light boundary structure for a light source, to be mounted thereon, wherein said light boundary structure is formed of at least two attachable parts including, respectively, a frame and at least one indicia area carrying panel removably mountable onto said frame defining together a six-sided box including the indicia carrying panel, an opposite side, and side walls, at least one of the side walls having a curved surface formed by at least two facets, said at least one indicia area carrying panel being a multi-layer structure formed by at least two layers patterned in accordance with the information to be displayed, an upper external layer of the multi-layer structure of the indicia area carrying panel having translucent regions of the indicia pattern and light blocking regions of the indicia pattern, and a lower inner layer of the multi-layer structure of the indicia area carrying panel having translucent regions of the indicia pattern and reflective regions of the indicia pattern, the illumination unit being thereby configured to increase the amount of light propagating from the light source to said at least one indicia area and enable replacement of the indicia area carrying panel to display different information, and enable visibility of the indicia area via internally reflected light.