Custom LCD need good backlight

[flowmeet]

For a custom transreflective LCD, 40mm x 80mm (1,5 x 3 inch approx) I was trying some oval leds, 3mm, 5mm, but it don't look very good, the light is not dispersed,,, some idea, I saw a few flat led models and I'll get a few of its and try, but help is appreciated...

Best Regards
Daniel H. Sagarra

 

[erikl]

What about a PMMA (acryl glass) pane with the LCD dimensions, optionally one side metalized, LED(s) attached to the face side (cross sectional side) of the pane? I think this is standard for cheap DVMs with backplane lighting.

 

[flowmeet]

Thank yo erikl for your fast answer, the light from the leds go through the cross section between the metalized side and the LCD contact side ?

 

[erikl]

Sure, that's how it's done. If you also metalize the (flat!) opposite cross section side, you loose less from the LED light. The LCD illumination is as uniform as the PMMA pane is (and its fixture to the LCD, of course).

For a trial, you can use a cyano-acrylate superglue to glue the LED(s) onto the cross-sectional side, and a (very flat) aluminum foil onto the backside and opposite side of the PMMA pane.

In an industrial production process, an aluminum CVD process would be used to create the mirror(s).