Patent ID: 7108414

Claim:
An optical assembly comprising a light emitting panel member having opposite sides and at least one input edge for receiving light from at least one light source, and a pattern of individual optical deformities on or in at least one side of the panel member for producing a light output distribution from a light emitting surface area of the panel member, the individual optical deformities being varied throughout the pattern to cause the light output distribution to be generally uniform and provide a generally uniform field of illumination for a liquid crystal display overlying the light emitting surface area except in a localized region within the uniform field of illumination where the individual optical deformities are varied to create a watermark, security marking, label or other effect within the uniform field of illumination having a form or shape of at least one of text, graphics, logo or image that is viewable through the display, each element of the text, graphics, logo or image being comprised of a plurality of the individual optical deformities which are quite small in relation to the length and width of each element of the text, graphics, logo or image formed thereby.