This is the liquid crystal display (LCD) used in the NXT. LCD of the NXT consists of 100 in the horizontal direction, 64 points in the vertical direction. In order to distinguish it from segment method such as calculator, we call the "dot matrix". Dot-matrix liquid crystal save the number of wiring, you could not view the point at once, but in order to display one line at a time (or a column). The NXT has been used liquid crystal display called "STN". STN method has the advantage that have definite shades of view, but has the disadvantage that the colored. Overall it is a green screen is due.
I tried to create a diagram of a simple structure of a liquid crystal display.
"LCD" means "such as liquid crystal". For example, water is set to "liquid" and freeze in "solid" at room temperature, the liquid crystal is the intermediate state. The LCD has a nature "the voltage is applied and it moves in a certain direction ", the contrast of the display has switched with that principle.