Patent ID: 8425062

Claim:
A display unit comprising: A display area for presenting visual information to a user of the display unit; a lens element spaced apart from and extending across the display area, the lens element including a peripheral edge and opposite inner and outer surfaces relative to the display area, wherein the inner surface is coated with a light collimating film and the outer surface is coated with a partially reflective layer; and a source of illumination arranged to project light into the peripheral edge of the lens element; wherein the inner and outer surfaces act as a light pipe to convey the light projected into the peripheral edge of the lens element through the lens element by means of multiple internal reflections off the inner and outer surfaces; wherein the partially reflective layer coated on the outer surface of the lens element partially reflects the light conveyed through the light pipe towards the inner surface and the light collimating film coated on the inner surface of the lens element controls a direction of the light reflected by the partially reflective layer towards the display area; wherein a portion of the light escapes from the inner surface of the lens element to illuminate the display area; and wherein the partially reflective layer coated on the outer surface of the lens element permits light from the illuminated display area to pass through the partially reflective layer so that the user can view the illuminated display area.