field emission displays
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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 - PowerPoint PPT PresentationTRANSCRIPT
The future of display technology?
Prepared By: Ryan MichaudAdam NealeAndrei Iakimtchik
Date: March 27th, 2007.
Presentation OutlineHistory of display technology Current display alternativesHow FEDs workCompanies working on FEDDifficulties with FEDFuture of FED displays
History of Display Technology
Cathode Ray Tube1950’s
Liquid Crystal Displays1970’s
Field Emission Displays1980’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)
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
CRT
Technology Comparison
Advantages Shortcomings
Good color representationLarge viewing angleFast response time (50 µs)Low priceMultiple resolutions
Large and bulky (2 kg/in)Flicker causes eye strainHigh power (11 W/in)
CRT
Technology Comparison cont’d
Technology Comparison cont’dLCD
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
Light weight (0.6 kg/in)Low power (5 W/in)Less eye strainHigh brightness (500 Cd/m2)
Small viewing angleSlow response time (8 ms)Weaker contrast & color
LCD
Technology Comparison cont’dPDP
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
High brightness (1000 Cd/m2) High contrast (10000:1)Large viewing angle
More power vs LCD (8 W/in)Burn-in effectSize limitation (>40”)Slow response time
PDP
FED: The Best of Both WorldsPromised 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 flickerNo 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 - SpindtSpindt 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 FEDCanon and Toshiba joint venture in SEDSony promises Spindt-type FED display in 2009Samsung 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 pricesLCD panels are dropping in cost while increasing
in quality
Hope for FED Displays
The success of FEDs depends on:CostQualityTiming
Technologically advantageous product suffers from poor timing
Questions?