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Field Emission Displays. The future of display technology?. Prepared By: Ryan Michaud Adam Neale Andrei Iakimtchik Date: March 27 th , 2007. Presentation Outline. History of display technology Current display alternatives How FEDs work Companies working on FED
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Field Emission Displays The future of display technology? Prepared By: Ryan Michaud Adam Neale Andrei Iakimtchik Date: March 27th, 2007.
Presentation Outline • History of display technology • Current display alternatives • How FEDs work • Companies working on FED • Difficulties with FED • Future of FED displays
History of Display Technology Cathode Ray Tube 1950’s Liquid Crystal Displays 1970’s Field Emission Displays 1980’s
Cathode Ray Tubes (CRT) • Geissler Tubes (1855) • First CRT oscilloscope invented 40 years later • Commercially practical CRT made by Allen DuMont (1931)
Liquid Crystal Display • Liquid Crystalline materials discovered (1880s) • James Fergason produced first practical LCD display (1967) • Epson introduced first color LCD TV 2” in diagonal (1985)
Plasma Display Panel • Plasma identified by William Crookes (1879s) • Prototype for PDP introduced at University of Illinois (1964) • Fujitsu introduced first 42” color PDP (1997)
Technology Comparison CRT • Vacuum tube with phosphor-coated screen • Cathode emits electrons to be accelerated by the anode • Deflectors guide the electron beams • Electrons excite phosphor molecules to produce light
Technology Comparison cont’d Advantages Shortcomings CRT • Good color representation • Large viewing angle • Fast response time (50 µs) • Low price • Multiple resolutions • Large and bulky (2 kg/in) • Flicker causes eye strain • High power (11 W/in)
Technology Comparison cont’d LCD • A layer of liquid crystalline sandwiched between 2 glass layers with polarizer • Light generated behind the screen, passed through • Applied voltage controls the crystalline orientation
Technology Comparison cont’d Advantages Shortcomings LCD Light weight (0.6 kg/in) Low power (5 W/in) Less eye strain High brightness (500 Cd/m2) Small viewing angle Slow response time (8 ms) Weaker contrast & color
Technology Comparison cont’d PDP • Two layers of glass with pixel array in between • Each pixel contains a mix of neon and xenon gas • Current is passed through a pixel to ionize gas, and emit UV radiation • UV rays excites phosphor-coated layer of glass to generate light
Technology Comparison cont’d Advantages Shortcomings PDP High brightness (1000 Cd/m2) High contrast (10000:1) Large viewing angle More power vs LCD (8 W/in) Burn-in effect Size limitation (>40”) Slow response time
FED: The Best of Both Worlds Promised Advantages • Very light (100 g/in) • Large Viewing angle (178o) • Extremely fast (20 ns) • Low power (0.2 W/in) • High contrast (10x PDP) • No flicker • No dead pixels
How FED Works? • Array of mini-CRTs
Technology Options - SED • “Surface-conduction electron emitter display” • Joint venture between Toshiba and Canon
Technlogy Options - Spindt • Spindt emitters are tiny cones that create a very high charge density • Alignment of the cone and gate is critical
Technology Options - CNT • Carbon nanotubes as electron source
Companies Researching FED • Canon and Toshiba joint venture in SED • Sony promises Spindt-type FED display in 2009 • Samsung is researching CNTs, Applied Nanotech Inc. have made a 25” display
Challenges: Technical Problems • Fluctuations in emission current • Low cost manufacturing methods • Developing for large areas • Tip damage • High vacuum levels required
Dropping LCD prices • LCD panels are dropping in cost while increasing in quality
Hope for FED Displays • The success of FEDs depends on: • Cost • Quality • Timing • Technologically advantageous product suffers from poor timing