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Bring polarizing film

Bring polarizing film. Palffy – Muhorray , “The Diverse World of Liquid Crystals”, Physics Today , Sept. 2007. Some slides need re-organizing and tighter message. First related observations: Myelin 1700s –1850. LC = a misnomer. These systems are not crystals….

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Bring polarizing film

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  1. Bring polarizing film Palffy – Muhorray, “The Diverse World of Liquid Crystals”, Physics Today, Sept. 2007 Some slides need re-organizing and tighter message.

  2. First related observations: Myelin 1700s –1850 LC = a misnomer. These systems are not crystals…. and the study is not necessarily confined to liquids either.

  3. Discovery is usually associated with the behavior of cholesteryl benzoate, which by ~1888 was known to have two melting points. Discovery due to Reinitzer & Lehman = Botanist & Physicist Note the rather extended shape! Irridescent beetle colors may Trace to “liquid” “crystal” behavior. (from a beetle wiki) See also SrinivasaraoScience 2009

  4. 1949 Onsager f > 4/x (x = L/d) kind of a pure packing argument, logs in a river photo. 1959 Maier Saupe extend to temperature; anisotropic polarizability below some crit temperature 1965 Kent State Glenn Brown

  5. classifications Nematic smectic (a,c), chiral Thermotropic, lyotropic

  6. http://www.texasbeyondhistory.net/timberhill/images/greatraft.htmlhttp://www.texasbeyondhistory.net/timberhill/images/greatraft.html The "Great Raft," a huge mass of timber that formed a logjam, dammed up the Red River and flooded the surrounding area. Photo by R. B. Taylor, courtesy Louisiana State University, Shreveport, Noel Memorial Library Archives.

  7. http://farm1.static.flickr.com/57/220279395_26a24ae64f.jpg

  8. Biaxial nematic http://the2manadvantage.blogspot.com/2007/10/nhl-is-opening-flagship-store-in-nyc.html http://www.thehockeyshop.com/hockey-sticks.htm

  9. LC’s as displays. Why do we need something besides the CRT? Vacuum! How heavy does a CRT have to be to be strong enough to maintain vacuum, since the e-beam has to travel from gun to phosphor screen? This is a fundamental limitation. By contrast, the limiting size of LCD’s = production yields of large, defect-free films. There is no fundamental limitation, merely a matter of engineering. The problem is CRTs have a heart of glass!

  10. Even so, very huge LCD displays are not with us yet; we use projection. For now. Casio Hybrid Projector Actually, this isn’t an LCD display. Doesn’t use a lamp either…. $800 gets you a “hybrid” light source with DLP technology. Animated GIF of how it works. LG HS201 Slim Sort of 6” x 6” size Not an LCD No lamp $550

  11. DIY LCD Projector Videos Heart of Glass doesn’t cut it in the plastics world: http://www.youtube.com/watch?v=FKrKHtdXroo OHP http://www.youtube.com/watch?v=NWlsPfPZTdc Cracker box: http://www.youtube.com/watch#!v=KZ_KpQV1Vmo&feature=related http://www.youtube.com/watch?v=n6n6jW0XIV0&feature=related DIY LCD Projector >500000 views

  12. The idea of using LCs for light display goes back to simple rubbing of glass experiments. 1911 It is found that rubbing glass can align the LC molecules; crossed rubbing leads to no transmission of light through the objects. 1922 word mesomorphic coined 1935 Freedericksz finds E field can align LCs 1936 patent (British) to Marconi for “light valves….for use in television, facsimile telegraph and other systems” Postwar: synthesis of mesogens By 1950s, a thriving subject

  13. Twisted nematic LC (Saupe 1969, KSU) How to twist it? How to switch it?

  14. From PC World ~2000 (I think)

  15. http://www.maxi-pedia.com/tft+lcd+display+monitor+panel

  16. The invention of the TFT made this practical in large arrays. The TFT was invented in 1973 by Westinghouse (120 x 120 pixels in 6” x 6” array = 0.05”/pixel). By this time, the USA had already ceded other video technology, such as video tape recording, to the Japanese. TFT/LCD panels met the same fate. http://en.wikipedia.org/wiki/TFT_LCD

  17. There are opportunities for polymers in this game. About 40% of Corning’s $4.6B revenues in 2006 came from LCD glass.So…how do you make a perfectly flat, bubble-free piece of glass? Plastics’ role: under 30” the sandwich can be made from plastic. From some website: The liquid crystal is placed between the two sheets in a patterned plastic sheet that divides the liquid into individual shutters and keeps the sheets at a precise distance from each other.

  18. Plasma….its days probably also numbered. Probably better quality than LCD, though. Plasma http://electronics.howstuffworks.com/plasma-display2.htm

  19. Research continues. This Fabry-Perot interferometer device requires poly(ethylene napthalate) which deflects to create a light gate at a particular color. http://spie.org/x8775.xml?ArticleID=x8775 PEN, even better barrier properties than PET This color display is flexible! Harry Potter-Style Newspapers a Reality http://www.dailymail.co.uk/news/worldnews/article-1207944/Harry-Potter-meets-Minority-Report-video-adverts-magazines-reality.html

  20. The future is probably with these technologies: OLED FED SED The LCD is limited by energy cost—tosses away an awful lot of light; 40” display about 250 W, same as CRT. Organic LEDs will light up just where/when you need. FED/SED display = array of nanotubes that makes electrons for phosphors just where/when you need them.

  21. Even others can be considered. Electronic paper Wiki 50 mm Palfy-Muhorray review article

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