What about the pins CE and C/E on the LCD Display.
I can't understand where i get the signal for this pins and what they do.
CE is, in all cases I know Chip Enable and must be active for you to talk to the chip, the datasheet for the display should indicate that.

Can i give the resistor signal direktly to a analog input?
The first place you go blind is on the eyes, but I see no resistor on your schematic.

Erik