REFLECTIVE MODE

LCD's employing the reflective viewing mode produce dark characters on a light background. (Positive Image) When a segment is turned off, ambient light travels through the following layers:

 1. The vertically aligned front polarizer located on the face of the display.
 2. The indium tin oxide segment pattern on the rear of the front glass substrate.
 3. Polyimide layer (alignment layer)
 4. The liquid crystal material where it is twisted 90º
 5. Polyimide layer (alignment layer)
 6. The ITO defined commons on the front of the rear glass substrate.
 7. The horizontally aligned rear polarizer behind the rear glass substrate.
 8. And finally onto a reflector that returns it along the same path. (See diagram E)

A positive image display has front and rear polarizers that are said to be "OUT OF PHASE" with one another, or "crossed polarized" by 90º. When a segment is TURNED ON, the LC molecules won't twist polarized light. Therefore, the light is OUT OF PHASE when it reaches the rear polarizer preventing it from passing through to the reflector. Because the light is not reflected, a dark or positive image is created for that particular segment.