The LCDs put for projection systems are usually small reflective or transmissive panels set off by a powerful arc lamp source. A series of lenses magnifies the reflected or transmitted image and sends it onto the screen. With front-projection systems the LCD is placed on the same side of the screen as the viewer, but in rear-projection systems the screen is lit from behind. Projectors of greater expense and capacity might be found with three separated LCD panels, casting separate red, green, and blue images that mesh to make a coloured picture on the screen.

The growth in requirement for pictographic presentations has granted a growth in emphasis on the switching speed of liquid crystals. This has necessitated the development of objects build with smectic liquid crystals, some of which have a quicker electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this point the most progressive smectic device. Within it the liquid crystal molecules are set out in perpendicular layers to the substrate planes, which are separated by one or two micrometres, and throughout the layers the molecules are slanted, as demonstrated in the figure. The host liquid crystal possesses optically active molecules, and a subtle consequence of the optical activity and the angle 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 throughout the plane of the layers. So, there has to be a permanent charge separation over the liquid crystal layer in the SSFLC, and its sign is directly attracted 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 resultant change in optical properties can create a change from light to dark if or when one or more polarizers are used.

SSFLC devices have been publicized for bigger passive-matrix presentations, but their high cost and detail has stopped them from having any great movement 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 used in time-sequential colour systems, in which expensive colour filters are emulated by a coloured backlight that flashes red, green, and blue in fast pulsing (approx 100 cycles per second). For example, the liquid crystal can be switched to a transmissive state between the red and green periods and to a nontransmissive state in the blue period, displaying the result that the eye sees an average of red and green light, or the colour yellow.

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