Back-lit display
AssigneeMinnesota Mining and Manufacturing Company
InventorsKenneth A. Aho, Jeffrey J. Melby, Richard A. Miller
Life of this patent
Estimating the term…
Abstract
A back-lit display utilizes a light transmissive film having a smooth surface and a structured surface. The structured surface has a series of triangular prisms running parallel or concentric to one another. A reflector is placed adjacent to the smooth surface so that light entering the film at an angle that is close to parallel to the smooth surface will emerge from the film at a predetermined angle with respect to the incoming beam. A display, that could be a liquid crystal display, is positioned so that light reflected by the film passes through it.
Claims18
A back-lit display comprising:
- a housing defining an optical cavity having an optical window;
- a light reflecting film in said optical cavity, said light reflecting film having first and second major surfaces, said first surface being a structured surface having a plurality of triangular prisms thereon and said second surface being a smooth surface, and a light reflecting means adjacent said second surface for reflecting light approaching said second surface from said first surface;
- a first light source positioned so that light rays approach said film in a direction that is almost parallel to said second surface of said film;
- and
- display means in said optical window.
Dependencies are inferred from the claim text.