Like smectic liquid crystals, cholesteric liquid crystals form a stratified structure,
but the major axis molecules form a parallel configuration similar to those in
nematic liquid crystals within the surface of each layer. The molecular axis configuration also deviates slightly in direction between contiguous layers, and the
overall liquid crystal has a helical structure. The optical properties of cholesteric
liquid crystals—including their optical rotation, selective light scattering, circular
polarization, and dichromism—are produced as a result of this helical structure.
B. Use of Liquid Crystals in Liquid Crystal Displays
The smallest particle producing an image on a liquid crystal display is called a cell;
images are displayed as individual cells reflect (polarize) or block light. The basic
process of using liquid crystals to produce a liquid crystal display comes in three
main types: base material production, cell production, and module production.
In simple terms, the base material production process involves removing
impurities from a transparent glass electrode board and creating a cast base material
that can be used for the display electrodes. The next process, cell production,
involves applying an organic polymer resin on two cast base material from the
previous process, conferring orientation layer and insulation layer functions.
Sealing adhesive and spacers are applied to produce a bowl-shaped cell with
adjustable thickness; the liquid crystal material injected here, and the polarizing
plate is attached to create the liquid crystal display shape. The final module production process involves assembling a base material arrange with the cell, a driver
direct circuit to drive the cell, and a power circuit, and a framework to support
electronic contact between the cell’s electrodes and the driver circuit. When an
electrical signal arrives in the resulting liquid crystal display, liquid crystal materials in each cell react to it and either reflect or block light, producing the desired
images.
C. Liquid Crystals from Marine Organisms
Cholesterol, the starting substance for cholesteric liquid crystals, is one of a group
of compounds known as sterols that have a cyclopentaphenanthrene carbon
framework. The sterols that make up its basic structure are found among a broad
range of animals, plants, and microorganisms; cholesterol in particular is found in
many animal cells. It is also abundant in the membranes of cells in higher-order
animals, including red blood cells and myelin sheaths, but scarce in the internal
membranes of mitochondria and bacterial cell membranes.
Recently, researchers have tried to use these abundant cholesterol compounds in
animal cells to produce liquid crystals, which are drawing attention as a
next-generation display device. This section will examine liquid crystals that can be
made from substances present in the seas’ abundant marine life.
For some years, cholesteric liquid crystals have been made with cholesterol
extracted from squid, sardines, and other marine animals. The reason for this is the
8.3 Bio Materials
249
but the major axis molecules form a parallel configuration similar to those in
nematic liquid crystals within the surface of each layer. The molecular axis configuration also deviates slightly in direction between contiguous layers, and the
overall liquid crystal has a helical structure. The optical properties of cholesteric
liquid crystals—including their optical rotation, selective light scattering, circular
polarization, and dichromism—are produced as a result of this helical structure.
B. Use of Liquid Crystals in Liquid Crystal Displays
The smallest particle producing an image on a liquid crystal display is called a cell;
images are displayed as individual cells reflect (polarize) or block light. The basic
process of using liquid crystals to produce a liquid crystal display comes in three
main types: base material production, cell production, and module production.
In simple terms, the base material production process involves removing
impurities from a transparent glass electrode board and creating a cast base material
that can be used for the display electrodes. The next process, cell production,
involves applying an organic polymer resin on two cast base material from the
previous process, conferring orientation layer and insulation layer functions.
Sealing adhesive and spacers are applied to produce a bowl-shaped cell with
adjustable thickness; the liquid crystal material injected here, and the polarizing
plate is attached to create the liquid crystal display shape. The final module production process involves assembling a base material arrange with the cell, a driver
direct circuit to drive the cell, and a power circuit, and a framework to support
electronic contact between the cell’s electrodes and the driver circuit. When an
electrical signal arrives in the resulting liquid crystal display, liquid crystal materials in each cell react to it and either reflect or block light, producing the desired
images.
C. Liquid Crystals from Marine Organisms
Cholesterol, the starting substance for cholesteric liquid crystals, is one of a group
of compounds known as sterols that have a cyclopentaphenanthrene carbon
framework. The sterols that make up its basic structure are found among a broad
range of animals, plants, and microorganisms; cholesterol in particular is found in
many animal cells. It is also abundant in the membranes of cells in higher-order
animals, including red blood cells and myelin sheaths, but scarce in the internal
membranes of mitochondria and bacterial cell membranes.
Recently, researchers have tried to use these abundant cholesterol compounds in
animal cells to produce liquid crystals, which are drawing attention as a
next-generation display device. This section will examine liquid crystals that can be
made from substances present in the seas’ abundant marine life.
For some years, cholesteric liquid crystals have been made with cholesterol
extracted from squid, sardines, and other marine animals. The reason for this is the
8.3 Bio Materials
249