Electro-optical properties and morphology of reverse scattering mode liquid crystal (LC) display, which shows a transparent voltage off-state and a light scattered voltage on-state, have been investigated. The display is prepared by using a twisted nematic LC layer doped with a photo-reactive mesogen (RM), which forms oriented polymer network. Driving voltage of this device strongly depends on a concentration of the RM, type of LC material and a UV power used to polymerize the RM. This is primarily due to the fact that these factors affect morphology of the polymerized RM. Large particles of the RM and the large domains of the LC attribute to the low driving voltage. We successfully obtained the driving voltage less than 4 V by optimizing LC material and morphology of RM network.

A coexistence with normal and reverse scattering modes is demonstrated in a single liquid crystal (LC) cell by using a polymer stabilized effect. The homogeneously oriented or twisted LC cell containing a small amount of reactive mesogen is exposed with UV light under a suitable curing voltage application. A light scattering state is obtained and it becomes clear by applying voltage. The cell fabricated without the curing voltage shows a reverse mode property, that is, a transparent voltage off-state and the light scattering on-state. A driving voltage of the normal mode is almost the same as that of the reverse mode. A domain with the normal mode property is successfully fabricated in the reverse mode LC cell by two step UV exposures through a photomask with and without the curing voltage. Scattering and transparent patterns simultaneously turns to transparent and scattering states without electrode partitions.

A normal mode property of which a light‐scattering state electrically changes to a transparent state and a reverse mode with the opposite switching property are demonstrated in an oriented reactive mesogen and liquid crystal composite cell. The light‐scattering domain is produced in the transparent cell by partly irradiated with a UV light under a suitable voltage application. Scattering and transparent patterns simultaneously electrically turn to the transparent and scattering patterns without electrode partitions.

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