Usually, LCD displays used in small clock are setup to be shown from the front. Our device needs to have the light source from behind, in transparence. So we need to modify the screen to let the light go through the display. However, the same could be used in reflection but in this case, the luminosity would be lower:

A typical LCD display is composed as seen on the picture.

The glass screen is placed between 2 polarized filters that orientates the light and allows for the time to be display in black on white.



To let the light go through the display, you will first need to remove the reflecting bottom of the screen. To get an inverted display (white on black), you will then need to remove the second polarized filtered and turn it by 90ÃÂ° clockwork or counter-clockwork, no mater. These two steps are quite difficult since the filter and reflecting surface are strongly stick together and very thin. When removing the filter from the screen, be careful not to damage them.