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The LCDs used in projection systems are generally small reflective or transmissive panels lit by a forceful arc lamp source. A line of lenses enlarges the reflected or transmitted image and displays it on the screen. With front-projection systems the LCD is set on the side of the screen as the viewer, but in rear-projection systems the screen is set off from behind. Projectors of higher cost and performance might use three discrete LCD panels, creating separate red, green, and blue images that blend to create a coloured image on the screen.

The increase in demand for pictographic presentations has placed a growth in emphasis on the switching speed of liquid crystals. This has demanded the creation of objects utilizing smectic liquid crystals, some types of which possess a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most progressive smectic device. Within it the liquid crystal molecules are managed in layers that are perpendicular to the substrate planes, which are separated by one or two micrometres, and throughout the layers the molecules are on a tilt, as illustrated in the figure. The host liquid crystal has optically active molecules, and a slight outcome of the optical activity and the tilt of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, likeable 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. Therefore, there has to 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 corresponding sign can reverse the direction of this dipole in tens of microseconds and in so doing reverse the tilt direction of the molecules. The respective change in optical properties can cause a change from light to dark if one or more polarizers are utilised.

SSFLC devices have been produced for bigger passive-matrix presentations, but their expensiveness and complexity has hindered them from creating any significant impact on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have shown some probability for use as parts in projection systems or as viewfinders in digital cameras. Their quick reacting allows them to be utilised in time-sequential colour systems, in which dear colour filters are emulated by a coloured backlight that flashes red, green, and blue in fast pace (approximately 100 cycles every second). For example, the liquid crystal may be switched to a transmissive state in the red and green periods and to a nontransmissive state during 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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