> Hey Jinx, have you taken apart a pre-backlit LCD ?

No, I haven't, not got one to pull to bits. Did wonder how it was
done. I don't recall ever seeing a glass LCD (eg multimeter type)
being backlit. Display area of these is about the size of a 16x4

> The ones I've seen have a plexiglas panel under the LCD. The panel
> is side lit with LEDs, and the back side of the panel (the one farthest
> from the LCD has a pattern of small white dots
> 
> Hope that helps.

Does, very interesting. Are the "white dots" actually painted or pits
moulded into the plastic ? I remember from my art and craft days
making cuts and holes into clear resin rods to make light come out
at the cut/hole. I was thinking some kind of pipe/guide with diffusing
features would work. Could be made from rod or sheet or some
combination, although I've got several dozen to do and don't want it
too complicated. A (simple) assembly or millable pattern is OK

Another thought was to paint either the underside of the LCD or
any acrylic sheet with phosphorescent dye and use UV LEDs in
the hope that the lit colour would spread out that way, but I've no
proof it would

Here's an explanation of the different types of display vis-a-vis how
the characters are seen

http://www.pacificdisplay.com/lcd_polarizers.htm

The actual LCD I'm using is a Displaytech equivalent of the Varitronix
VI-402 transflective. Maybe I could light it from the front. The case is
2mm black plastic into which I'll mill a cut-out. Then use a piece of
3mm acrylic with a 2mm flange milled around the edge. It's possible that
1mm of acrylic edge inside the case could be lit

One other thing - why am I up at 7am on Boxing Day fussing about
how to backlight an LCD ? ;-)))

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