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Adding CCFL light or LED backlight to a 6 digit/7 segment LCD display

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hafrse

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Hello,

Is possible to add CCFL light or LED backlight to a 6 digit/7 segment LCD display which has no backligt from the beginning? I have seen some article about doing that many years ago (could not find now...) by removing the reflective shield layer from the backside , not sure if I should seprate that shield from a possible layer (polirization ?) between it and the LCD glas or other consideration that I should be aware off.
ATtached 2 images from the LCD display
Mnay thanks in advance!.
 

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KlausST

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Hi,

There are some displays that are especially made for both operating modes. But it's a compromise.
If you have one made with reflective back then I doubt it will work because:
* the back won't let the backlight go through
* the polarisation won't work perfectly

Klaus
 
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betwixt

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I agree with Klaus. The contrast is largely dependent on the distance light passes through the polarizing layer and back again, if you remove the reflector it may not work at all.

Try aiming an LED into the edge of the glass first, I have several units here that just use white 5mm LEDs aiming into to short sides of the display and they are perfectly readable.

Brian.
 
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hafrse

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Thanks, I will try that :)

- - - Updated - - -

Hi,

There are some displays that are especially made for both operating modes. But it's a compromise.
If you have one made with reflective back then I doubt it will work because:
* the back won't let the backlight go through
* the polarisation won't work perfectly

Klaus

Thanks, will not take away the backside since I only have this display to work with.
 

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