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The LCDs utilised for projection systems are usually small reflective or transmissive panels lit up by a bright arc lamp source. A line of lenses enlarges the reflected or transmitted image and then casts it on a screen. For front-projection systems the LCD is placed on the same side of the screen as the viewer, while in rear-projection systems the screen is set off from behind. Projectors of greater expense and capability can utilise three separate LCD panels, casting separate red, green, and blue images that blend to reflect a coloured display on the screen.

The growth in requirement for film displays has had a growing emphasis on the switching speed of liquid crystals. This has required the creation of devices employing smectic liquid crystals, some of which give a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most progressive smectic device. With it the liquid crystal molecules are arranged in perpendicular layers to the substrate planes, which are distanced by one or two micrometres, and throughout the layers the molecules are tilted, as displayed in the figure. The host liquid crystal contains optically active molecules, and a slight turn up of the optical activity and the slant of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, analogous to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and within the plane of the layers. Therefore, there exists a permanent charge separation through the liquid crystal layer in the SSFLC, and its sign is directly paired up 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 in so doing reverse the tilt direction of the molecules. The consequential change in optical properties can make a change from light to dark if one or more polarizers are employed.

SSFLC devices have been publicized for bigger passive-matrix displays, but their high cost and complex detail has impeded them from creating any remarkable impact on the market. Small transmissive and reflective active-matrix SSFLC displays, however, display some promise for use as elements in projection systems or as viewfinders in digital cameras. Their quick response allows them to be used in time-sequential colour systems, in which dear colour filters are replaced with a coloured backlight that flashes red, green, and blue in quick speed (around 100 cycles every second). For example, the liquid crystal could be switched to a transmissive state for the red and green periods then to a nontransmissive state during the blue period, having the upshot that the eye sees an average of red and green light, or the colour yellow.

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