The LCDs utilised in projection systems are typically small reflective or transmissive panels lit by a bright arc lamp source. A line of lenses enlarges the reflected or transmitted image and then sends it on a screen. For front-projection systems the LCD is set on the same side of the screen as the viewer, however in rear-projection systems the screen is set off from behind. Projectors of greater expense and capability sometimes have three separated LCD panels, casting separate red, green, and blue images that combine to make a coloured image on the screen.

The increasing requirement for pictographic presentations has put a growth in emphasis on the switching speed of liquid crystals. This has led to the creation of objects employing smectic liquid crystals, certain kinds of which possess a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is in the current day the most developed smectic device. Within it the liquid crystal molecules are cast in perpendicular layers to the substrate planes, which are differentiated by one or two micrometres, and throughout the layers the molecules are on a slant, as displayed in the figure. The host liquid crystal possesses optically active molecules, and a slight turn up of the optical activity and the angle of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, similar to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and throughout the plane of the layers. Thus, there is a permanent charge separation through the liquid crystal layer in the SSFLC, and its sign is directly coupled to the tilt direction of the molecules. An applied voltage of the right sign can reverse the direction of this dipole in tens of microseconds and so reverse the tilt direction of the molecules. The respective change in optical properties can create a change from light to dark when one or more polarizers are employed.

SSFLC devices have been commercialized for bigger passive-matrix displays, but their high cost and intricacy has hindered them from enjoying any significant effect on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some promise for use as parts in projection systems or as viewfinders in digital cameras. Their fast reaction allows them to be used in time-sequential colour systems, in which expensive colour filters are replaced with a coloured backlight that flashes red, green, and blue in fast speed (around 100 cycles in a second). For example, the liquid crystal can be switched to a transmissive state for the red and green periods but then to a nontransmissive state during the blue period, with the outcome that the eye sees an average of red and green light, or the colour yellow.

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