Liquid-crystal display prospects in perspective

The advantages of dynamic scattering liquid-crystal displays--extremely low power consumption, flexibility of size and format, color choice, and washout immunity--are not obtained without cost. Long life requires ac drive and hermetic packaging. The optical characteristics of dynamic scattering make it difficult to design a display that utilizes the liquid-crystal panel effectively under a variety of lighting conditions. Multiplexed drive is cumbersome at best, so cost of drive electronics for more than about four digits is higher than with competing display technologies. The development of twisted nematic displays will reduce drive costs and improve appearance although the changes will not be revolutionary. The large multiplexing capability or color variability of the alterable birefringence effect is offset by prohibitive manufacturing tolerances and narrow field of view. Led by low-power digital wristwatches, liquid crystals should achieve a substantial market in applications whose requirements match unique display properties. Effective penetration of the consumer mass market will await improved field-effect devices and reductions in semiconductor packaging costs.