Passive-matrix LCD is an LCD technology that uses a grid of vertical and horizontal conductors
comprised of Indium Tin Oxide (ITO) to create an image. Each pixel is controlled by an
intersection of two conductors. By creating a potential voltage difference at an intersection, the
LC fluid is able to respond by creating an “on” state at that intersection, also commonly referred
to as a pixel.
While relatively simple and inexpensive to produce, passive-matrix displays do have a few
drawbacks. Because the charge of the two conductors (rows and columns) is addressed only one
row at a time, the response time of passive-matrix displays is relatively slow, and the contrast is
greatly reduced over that of an active TFT display.
An active-matrix display, or Thin Film Transistor (TFT), utilizes a silicon backplane instead of
the more basic Indium Tin Oxide (ITO) conductive surface used on the passive LCD display.
This silicon backplane enables the creation of a transistor at each pixel location, which holds the
LCD charge in between row-addressing cycles. This main charge-holding difference allows the
active-matrix LCD to use a TN LC fluid with active addressing, which results in higher contrast,
reduced response time, and better viewing angles. Active-matrix displays are usually combined
with a color filter to create a full-color TFT cell.