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Let us take a break here and read on how different transparent LCDs are compared to your regular LCDs. First of all, regular LCD panels require the presence of BLUs (Back Light Units) as a light source so that an image can be displayed. BLUs are more or less crucial for the operation of all LCD panels, as not having any light source would be equal to seeing nothing. As for transparent LCDs, it uses other available light sources in the vicinity such as sunlight and in-door lighting. The question is, what happens at night? Well, in the midst of darkness, this is where the transparent BLU kicks in – one that was specially designed for transparent panels and to function as a light source.
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