Backlit prints

Imagine wallpaper that switches on to brighten the room, or floor tiles that glow underfoot, or even a photo album with pictures that glow on demand.

Kodak researchers in Rochester, New York, US, have been doing a lot more than imagining. Recently filed patents reveal how photographic prints, or inkjet printing paper, can be made to self-illuminate.

Kodak’s new paper has a backing sheet made from a three-layer sandwich. A thin metallic sheet is coated with a smooth layer of white-light phosphor, similar to that used in a black and white TV tube, and the phosphor layer is topped with a transparent metal film.

The backing sandwich is then either coated with the silver halide chemicals used to make conventional photo prints, or the dye absorbing layers used for inkjet printing paper. Polymer glues hold the layers together, add strength and seal against atmospheric damp.

When electrical current flows from one metal layer, through the phosphor powder, to the other metal layer, a glow is produced. This provides a uniform backlighting for the images printed over the top.

The effect requires about 100 volts at several hundred hertz but very low current – similar to a pocket LCD screen. A transparent polymer coating acts as an insulator to protect against any tingle if touched.

Kodak has made the backlit paper thin enough to pass through a conventional printer and flexible enough to fit in a photo album.

Get full details of what Kodak is hatching, here. (Warning! link to patent application, and lots of potentially disinteresting engineering material)

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Pulled from NewScientist.com