The LCDs used for projection systems are typically small reflective or transmissive panels illuminated by a forceful arc lamp source. A number of lenses expands the reflected or transmitted image then sends it onto a screen. In front-projection systems the LCD is situated on the side of the screen as the viewer, while in rear-projection systems the screen is lit up from behind. Projectors of higher cost and capability sometimes utilise three separated LCD panels, casting separate red, green, and blue images that blend to reflect a coloured image on the screen.

The growth in demand for pictographic presentations has granted a special emphasis on the switching speed of liquid crystals. This has led to the manufacture of objects build with smectic liquid crystals, some kinds of which emit a faster 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 layers that are perpendicular to the substrate planes, which are differentiated by one or two micrometres, and within the layers the molecules are tilted, as illustrated in the figure. The host liquid crystal holds optically active molecules, and a scarcely perceptible consequence of the optical activity and the angle of the molecules is the appearance 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 within the plane of the layers. Hence, there must be a permanent charge separation across 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 hence reverse the tilt direction of the molecules. The resultant change in optical properties can cause a change from light to dark when one or more polarizers are used.

SSFLC devices have been marketed for bigger passive-matrix displays, but their cost and intricacy has impeded them from enjoying any great effect on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have shown some possibility for use as aspects in projection systems or as viewfinders in digital cameras. Their speedy responding allows them to be utilised in time-sequential colour systems, in which highly expensive colour filters are replaced by a coloured backlight that flashes red, green, and blue in quick succession (about 100 cycles in a second). For example, the liquid crystal may be switched to a transmissive state in the red and green periods and then to a nontransmissive state in the blue period, displaying the upshot that the eye sees an average of red and green light, or the colour yellow.

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