Origin of polarizing

These iodine compound crystallizes very small, so in practical applications has been greatly restricted , Dr. Herapath spent nearly a decade to study how to make a larger polarized crystals , but he did not succeed . Therefore, rand that this road may not be feasible , Coding System lcd module so he used the following methods:
● Rand grinding the crystals large particles (ball mill) into tiny crystals and that these small crystals suspended in the liquid.
● Insert a plastic sheet into the suspension , then placed in a magnetic field or electric field orientation .
● this plastic film is removed from the suspension , the crystal will be polarized with cover on the surface of the plastic sheet .
● plastic sheet to stay in this magnetic or electric field, drying becomes a polarizing film .
Rand is a polarization many small crystals , a regular arrangement of well , which is equivalent to a large polarizing crystals. He applied the method described above ,128x64 oled in 1928, made ​​the first successful advent of the polarizing film , J film. The disadvantage of this method is time consuming , costly and fuzzy opaque. It has been found that the manufacturing polarizing Rand several important factors: ( 1 ) iodide ( 2 ) Polymer ( 3 ) Orientation (Orientation). Through continuous research and improvement , Rand finally in 1938 to the present invention, a method of manufacturing is still in use , the basic principle will be discussed in the next section .