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Who holds patent for LCD, Plasma, LED technology

I have been hearing SONY holds these patents and then licensed others to manufacture ...but is it true?

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Scott CSenior Systems EnginerCommented:
Look down in the References section:


You will see a list of patents.

This one is for the LCD:

Tony GiangrecoCommented:
Here are the official patent holders according to the Wikipedia site along with a link where this info was found:


European Patent No. EP 0131216: Amstutz H., Heimgartner D., Kaufmann M.,Scheffer T.J., "Fl├╝ssigkristallanzeige," Oct. 28, 1987.

U.S. Patent 3,834,794: R. Soref, Liquid crystal electric field sensing measurement and display device, filed June 28, 1973.

U.S. Patent 5,576,867: G. Baur, W. Fehrenbach, B. Staudacher, F. Windscheid, R. Kiefer, Liquid crystal switching elements having a parallel electric field and betao which is not 0 or 90 degrees, filed Jan 9, 1990.

U.S. Patent 5,598,285: K. Kondo, H. Terao, H. Abe, M. Ohta, K. Suzuki, T. Sasaki, G. Kawachi, J. Ohwada, Liquid crystal display device, filed Sep 18, 1992 and Jan 20, 1993.

In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve".

On December 4, 1970, the twisted nematic field effect in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.[6] Hoffmann-La Roche then licensed the invention to the Swiss manufacturer Brown, Boveri & Cie who produced displays for wristwatches during the 1970s and also to Japanese electronics industry, which soon produced the first digital quartz wrist watches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.[12]

In 1971 the company of Fergason ILIXCO (now LXD Incorporated) produced the first LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption.

In 1972, the first active-matrix liquid-crystal display panel was produced in the United States by T Peter Brody's team at Westinghouse, in Pittsburgh, Pennsylvania.[13]

In 1983, researchers at Brown, Boveri & Cie (BBC), Switzerland, invented the super-twisted nematic (STN) structure for passive matrix addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7,

1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,[14] U.S. Patent 4,634,229 and many more countries.

In 1990, under different titles inventors conceived electrooptical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates (Abstract).[15] To take full advantage of the properties of this In Plane Switching (IPS) technology further work was needed. After thorough analysis, details of advantageous embodiments are filed in Germany by Guenter Baur et al. and patented in various countries (Abstract).[16] The Fraunhofer Institute in Freiburg, where the inventors worked, assigns these patents to Merck KGaA, Darmstadt, a supplier of LC substances.
Tony GiangrecoCommented:
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