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The LCDs used in projection systems are generally small reflective or transmissive panels set off by a powerful arc lamp source. A series of lenses enlarges the reflected or transmitted image and sends it on the screen. With front-projection systems the LCD is set on the same side of the screen as the viewer, while in rear-projection systems the screen is set off from behind. Projectors of more expense and capacity may utilise three separated LCD panels, creating separate red, green, and blue images that blend to reflect a coloured picture on the screen.

The growth in need for pictographic displays has placed a special emphasis on the switching speed of liquid crystals. This has required the creation of items build with smectic liquid crystals, particular types of which possess a better 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 arranged in layers that are perpendicular to the substrate planes, which are distanced by one or two micrometres, and in the layers the molecules are tilted, as illustrated in the figure. The host liquid crystal contains optically active molecules, and a subtle result of the optical activity and the angle 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 in the plane of the layers. So, there has to be a permanent charge separation throughout 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 right sign can reverse the direction of this dipole in tens of microseconds and so reverse the tilt direction of the molecules. The consequential change in optical properties can effect a change from light to dark when one or more polarizers are employed.

SSFLC devices have been commercialized for large passive-matrix presentations, but their expense and complex nature has hindered them from enjoying any remarkable impact on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have shown some probability for use as aspects in projection systems or as viewfinders in digital cameras. Their fast responding allows them to be made use of in time-sequential colour systems, in which expensive colour filters are replaced with 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 for the red and green periods but then to a nontransmissive state in the blue period, with the upshot that the eye sees an average of red and green light, or the colour yellow.

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