The LCDs put for projection systems are typically small reflective or transmissive panels set off by a strong arc lamp source. A number of lenses enlarges the reflected or transmitted image and sends it on a 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 lit from behind. Projectors of more expense and capacity sometimes have three discrete LCD panels, casting separate red, green, and blue images that combine to make a coloured image on the screen.

The growth in need for pictographic presentations has put a growing emphasis on the switching speed of liquid crystals. This has led to the invention of objects using smectic liquid crystals, some types of which give a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is currently the most developed smectic device. Within it the liquid crystal molecules are cast in perpendicular layers to the substrate planes, which are distanced by one or two micrometres, and inside the layers the molecules are slanted, as illustrated in the figure. The host liquid crystal has optically active molecules, and a subtle consequence of the optical activity and the shape of the molecules is the appearance 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 in the plane of the layers. Therefore, there is 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 make a change from light to dark in the case that one or more polarizers are utilised.

SSFLC devices have been commercialized for large passive-matrix presentations, but their cost and intricacy has impeded them from creating any remarkable progress 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 immediate reacting allows them to be utilised in time-sequential colour systems, in which expensive colour filters are replaced by a coloured backlight that flashes red, green, and blue in quick speed (around 100 cycles in a second). For example, the liquid crystal could be switched to a transmissive state between the red and green periods but then to a nontransmissive state during the blue period, with the end result that the eye sees an average of red and green light, or the colour yellow.

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