The LCDs put for projection systems are generally small reflective or transmissive panels illuminated by a forceful arc lamp source. A number of lenses expands the reflected or transmitted image then casts it onto the screen. In front-projection systems the LCD is placed on the same side of the screen as the viewer, however in rear-projection systems the screen is lit up from behind. Projectors of greater expense and performance may utilise three separate LCD panels, reflecting separate red, green, and blue images that come together to form a coloured image on the screen.

The growing need for pictographic presentations has had a growing emphasis on the switching speed of liquid crystals. This has demanded the manufacture of objects using smectic liquid crystals, particular types of which have a quicker electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most developed smectic device. Inside it the liquid crystal molecules are arranged in perpendicular layers to the substrate planes, which are distanced by one or two micrometres, and within the layers the molecules are tilted, as shown in the figure. The host liquid crystal contains optically active molecules, and a minor result of the optical activity and the tilt of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, comparable 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 paired 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 respective change in optical properties can make a change from light to dark if one or more polarizers are used.

SSFLC devices have been publicized for large passive-matrix presentations, but their expense and complex nature has impeded them from having any remarkable effect on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have displayed some possibility for use as parts in projection systems or as viewfinders in digital cameras. Their speedy response allows them to be made use of in time-sequential colour systems, in which costly colour filters are replaced by a coloured backlight that flashes red, green, and blue in quick speed (approximately 100 cycles per second). For example, the liquid crystal may be switched to a transmissive state between the red and green periods then to a nontransmissive state during the blue period, having the outcome that the eye sees an average of red and green light, or the colour yellow.

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