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In this dissertation, liquid crystal (LC) molecules were used as the main building block for research and invented devices. LC molecules have amazing physical and chemical properties because they exist in a phase between liquid and crystal. Depending on their intrinsic properties and their interaction with surroundings, different states of LCs can exist. The beauty of LCs is that position and orientation of the majority of LC molecules can change by their interaction with proper surroundings materials or by an applied electric field. LC molecules also have a birefringence. In the last couple of decades, studies of the optical birefringence properties of LC molecules, in addition to change of position and reorientation by applied electric field have led to useful electro-optical devices for human beings such as liquid crystal displays (LCDs).During these years, much effort was made to improve the quality and light efficiency of LCDs. In recent years, large LCD companies are looking for a new generation of LCDs for broader application. Additionally, the light efficiency of LCDs is inherently poor since the LC cell is often sandwiched between crossed polarizers, which leads to a minimum loss of 50%. We carried out research on the design and fabrication of new generation LCD devices for broad application. In addition, we focused on solving the current LCD’s light efficiency problem, which would lead significant advancement for LCD industry.In this work, LC/polymer composites were used to design and fabricate four novel LC devices to bring new generations of LCD and improving the light efficiency of current LCD technologies significantly. These devices are LC/polymer diffuser, bistable light shutter, active and passive polarizing light waveguide plate (PLWG). These invented LC devices were used to create a transparent display for the new generation of LCDs. A bistable light shutter was created for application in reflective display as well as smart windows. A PLWG for improving LCDs fundamental light extraction design was fabricated that can dramatically increase the light efficiency of current LCD technology from 50% to 83%.The results obtained here can be used as a base for deeper understanding and improvement on these invented devices. The dissertation is divided as follows:In Chapter 2, various LC properties such as LC phase, and dielectric properties are introduced. Cholesteric LC is introduced and different states and transition between the states are discussed. Propagation of light in LC media and cholesteric LCs are described. Finally, the main principles of device fabrication with LC/polymer composites and their optical scattering properties are discussed.In Chapter 3, the new idea of using polymer stabilization of cholesteric LC for transparent displays is introduced. Polymer networks can stabilize the state of the cholesteric LC; in that way the devices can either scatter the incident light or become optically transparent with applied voltage. This light shutter was modified and used as a light diffuser to make the transparent display.In Chapter 4, two new techniques for making bistable LC light shutters are disussed. Bistable light shutters made by cholesteric LC polymer composites can be used for smart windows and low power consumption displays. In Chapter 5, the novel concept of using an active PLWG as a diffuser for LCDs is reported. Current LCD diffusers provide unpolarized light, but a PLWG can produce partially polarized light and therefore can increase light efficiency by greater than 50%. A PLWG is highly desirable as a diffuser for transparent displays since PLWGs can increase the light efficiency of displays. A passive PLWG plate is introduced in Chapter 6. This type of waveguide can be used in regular LC displays (LCDs). Different scattering properties of PLWG were studied. The advantage of this technique is that the light efficiency of current display technology can be increase without applying voltage. This technique is a breakthrough in LCD design. A