There have been previous efforts to reduce or eliminate the visibility of such status indicators when in the off state. One such prior technique preserves the integrity of the display surface by reducing the thickness of a metallic display panel from the rear in the region or area of the status indictor. The thickness is reduced until the metallic display panel actually becomes light-transmissive. When light is then shined on the rear or back side of the metallic display panel, it passes through that region and becomes visible on the opposite (outer or front) side of the metallic display panel. Thus, by thinning the metal only from the back side, the opposite side of the metallic display panel remains smooth, untouched, and uninterrupted. As such, the status indicator region in the off or unilluminated state cannot be distinguished and is invisible from the unmodified outside surface of the metallic sheet.
In one implementation of this technique, a matrix of holes was formed from and into one side (e.g., the “back side”) of a metal sheet nearly to the surface of the other side (e.g., the “front side”). For example, using laser ablation on an aluminum sheet, the holes were formed from the back side of the metallic aluminum sheet until there was a thickness of metal remaining at the front side on the order of only 12-20 nm. The matrix of holes was configured in the shape of a desired indicator, such as an arrow. The very small thickness of metal remaining at the end of each hole at the front surface of the metallic aluminum sheet allowed light to pass outwardly through the front surface of the sheet when the light was shined into the holes from the back surface thereof.