In 1850, Prussian doctor Rudolf Filsau and others discovered that the extract of nerve fibers contained an unusual substance.
In 1877, German physicist Otto Lehman observed the phenomenon of liquid crystalization using a polarizing microscope.
On March 14, 1883, the plant physiologist Federer Leinitzer observed that cholesterol benzoate has two melting points when it is melted.
After repeatedly confirming his discovery in 1888, Leinitzer began to consult the German physicist Lehman. At that time, Lehman built a microscope with heating function to observe the process of liquid crystal cooling and crystallization, but from that time Lehman has focused all its energy on this type of substance.
"Molecular Physics" was published in 1888. This is a summary of his knowledge in the field of materials physics during this period. In particular, he proposed the microscope research method in the book, through the crystal microscope and some observations made with it.
The 20th century chemist Volland used his experience to predict which type of compound is most likely to exhibit liquid crystal properties, and then obtained the compound properties by synthesis, and then Lehman's liquid crystal theory was proved.
In 1922, the Frenchman Fried carefully analyzed the existing liquid crystals and divided them into three categories: cholesteric, smectic, and nematic.
After Fried's analysis from 1930 to 1960, the research on liquid crystals temporarily entered a low point. Some people also said that the period from 1930 to 1960 was a blank period for liquid crystal research. The reason should be that no practical application of liquid crystal was found at that time. However, during this period, the semiconductor electronics industry has achieved extraordinary development. In order to allow the application of liquid crystals in displays, the patterning of transparent electrodes and the microfabrication technology of the integration of liquid crystals and semiconductor circuits must be indispensable. With the development and progress of the semiconductor industry, these technologies have become mature.
In the 1940s, silicon semiconductors were developed, using N-type semiconductors that conduct electrons and P-type semiconductors that conduct holes to form a PN interface, so diodes and transistors were invented. In order to realize the entire flow function from AC to DC in the circuit, diodes are used, but to realize the amplification function, electron tubes are used. Such large and bulky components can be completely replaced by semiconductor diodes and transistors. There is no need to emit electrons into the vacuum. As long as they are in a solid, especially a very thin film, the rectification and amplification functions can be realized, so that the electronic circuit can be realized. miniaturization. Next, the use of optical processing technology to achieve thinning and ultra-miniaturization of electronic circuit patterns including diodes and transistors. This technique is called lithography for short.
From the 20th century to the 1960s, with the development of semiconductor integrated circuits, electronic equipment has been miniaturized. The advancement of the above-mentioned technology is essential for the application in industrial LCD screen devices. With the increase of materials, the further development of science and materials plus engineering technology, as well as the development of new display modes and some driving technologies, liquid crystal display technology Obtained rapid development.
With the development of semiconductor integrated circuits in the 1960s, electronic equipment has been miniaturized.
In 1968, G.H. Heilmeier of RCA Corporation of the United States announced an industrial LCD display device using DS mode. After this, American companies first started the practical trial of digital broken code LCD screen watches.
In 1971, a Swiss company produced the first LCD monitor.
