The LCDs utilised in projection systems are generally small reflective or transmissive panels set off by a strong arc lamp source. A number of lenses enlarges the reflected or transmitted image and then sends it onto the screen. For front-projection systems the LCD is situated on the same area of the screen as the viewer, however in rear-projection systems the screen is set off from behind. Projectors of more expense and performance might be found with three discrete LCD panels, creating separate red, green, and blue images that mesh to form a coloured display on the screen.

The growing need for video displays has put a growing emphasis on the switching speed of liquid crystals. This has demanded the development of items build with smectic liquid crystals, certain ones of which emit a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is in the current day the most progressive smectic device. Inside it the liquid crystal molecules are managed in layers that are perpendicular to the substrate planes, which are distanced by one or two micrometres, and within the layers the molecules are on a tilt, as illustrated in the figure. The host liquid crystal holds optically active molecules, and a scarcely perceptible turn up of the optical activity and the tilt 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 through the plane of the layers. So, there exists 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 correct sign can reverse the direction of this dipole in tens of microseconds and by doing so reverse the tilt direction of the molecules. The consequential change in optical properties can effect a change from light to dark if or when one or more polarizers are employed.

SSFLC devices have been commercialized for large passive-matrix displays, but their expense and complexity has prevented them from enjoying any significant movement on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have displayed some promise for use as parts in projection systems or as viewfinders in digital cameras. Their fast response allows them to be utilised in time-sequential colour systems, in which high cost colour filters are emulated with a coloured backlight that flashes red, green, and blue in rapid pulsing (approximately 100 cycles every second). For example, the liquid crystal could be switched to a transmissive state during the red and green periods then to a nontransmissive state during the blue period, displaying the end result that the eye sees an average of red and green light, or the colour yellow.

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