The properties of some compounds with the characteristics of the liquid and the solid have different applications in the electronic that improve some of elements in our daily living.
A liquid crystal, is a phase between the liquid and solid (called mesophase), in which the compound have the capacity of a free movement like liquid but have at the same time a orderly structure like the solid. The discovery was made by Reinitzer at the end of the nineteenth century. The general description gave by the structure of this state of matter is a group of molecules with a weak dipole-dipole interaction which have the enough energy to stay the orientation in the material (electron cloud makes a repulsion and attraction balance to give a common orientation between the molecules) but not enough to restrict the movement of the sample.
The most important characteristic in the different types of liquid crystal ( nematic, esmectic and colesteric) is the capacity of change the direction, the intensity or the color of a light ray, depending of the optic axis where is observed, like normal solid crystal that have applications in googles or polarized glass used to protect us from the sun; but the way of work of the liquid crystal is better, the optic axis can be changed of orientation because this have a weak interaction between the molecules and answer at the presence of magnetic field turning in a perpendicular or parallel way to the field.
The nematic crystal composition make it good for the pass of the light, one example is the electro-optical indicator, a nematic is ubicated in the middle of two glass linked to a polarizator to make the alineation searched in the object (a change of 90° in the direction of the molecules) after this, when the light pass, all the objects have the same direction to give pass to the light, the two polarizator and the glass can leave the light pass in both ways, in this case, the indicator have a mirror in the inferior part, to reflect the light back and an observator can see this very clear and transparent. After this if you make pass some electricity to certain areas with two electrodes to change the orientation of the nematic liquid crystal, and don’t let the light pass in both ways, only one and form a number or letter very obscure.
This work is used in digital calculators or clocks, to make glass like drape if the person decide it, the construction of very little thickness television, can give pass of different kind of light color depending of the application of electricity in the system and the possible next principal component of space ships panels, in the last case this offer high resistence to the heat, humidity and ambiental conditions, very fickle and cheaper than the ceramic work in the case, can give a good capcity of radiofrequency over the 110Ghz compared to the normal system with only 5Ghz that begin to work slow over this frequency; only needs to pass the low temperature and radiation test to be used in this new field.
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