LED

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Author:
yhliuaa
ID:
202003
Filename:
LED
Updated:
2013-02-24 09:53:08
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LED
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LED
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  1. conventional lighting
    • incandescent
    • CEL
    • HID
    • halogen
  2. Luminaire efficacy
    efficacy of the complete luminaire, or fixture (taking into account the optics, thermal design, and other design factors) in lumens per watt. = total light output of a luminaire / amount of power (lm/W)
  3. Source efficacy
    efficacy of the light source, separate from the fixture in lumens per watt. (It does not account for losses caused when that system is installed in a fixture.)= total light output of a lamp power supply system / power drawn by that system. (lm/W)
  4. working principle of LED
    • LED (Light Emitting Diode) consists of two different semiconductor placed side by side with a p-n junction
    • there are holes on the p-side to be filled with electrons 
    • there are extra electrons on the n-side that are free to move around
    • when a current passes through, the holes and electron move to the junction, the electron loses energy to fill to hole and releases energy in the form of photon
  5. challenges of LED lighting
    • efficacy droop
    • better understanding on lifetime, failure mechanism and reliability 
    • Lower cost LED packages and luminaire materials are needed
    • Lack of process and component uniformity
    • No standard testing method
  6. OLED adoption barrier
    • high cost(material cost cut by higher emittance and waste minimization)
    • • Extraction of warm white light from the device
    • • Reduce the drive voltage by reducing the effective resistance between the electrodes .
    • low lumen output
    • • Research into the design of external films that will control the light distribution and enhance extraction
    • short shelf life and operating lifetime
    • NO standard testing
    • tough competition with LED backlight
  7. Solid-state lighting (SSL) technology
    uses semi-conducting materials to convert electricity into light.
  8. advantages of LED
    • low overall cost
    • no mercury
    • high energy efficiency
    • long lifetime
    • smaller size
    • faster switching
  9. why is LED lighting gaining popularity in residential lighting market
    • Fast decline in price-competitive with that of CFL
    • phasing out of inefficient light bulbs due to regulations(esp. in China and Europe)
  10. setbacks on popularity of LED in office lighting market
    • uses fluorescent technology, LED does not outperform in terms of efficacy
    • savings on energy is rewarded to tenants, not the owner who manage the lighting facilities in the office
  11. factors affecting LED growth in automotive lighting market(now mainly used for indicators and brake lighting)
    • for ultra-high brightness applications, it is expensive to use LED compared to HID and halogen lamps
    • regulations  in EU requires car manufacturer to use LED in daytime lamps
  12. key players
    • philips
    • osram
    • ge
    • cree
    • nichia
    • seoul semiconductor
    • Toyoda Gosei
    • Agilent Technologies
  13. applications
    • backlighting for TV, monitors, mobile devices
    • architectual lighting
    • general lighting
  14. philips key advantage
    • deliver complete light solutions 
    • leader luminaires company
    • >140licensing programs
    • heat sink
    • “Flip-Chip” packaging technology
    • Leading in high-power white lighting tube development
    • developed OLED
  15. factors contributing to philips' advantages
    • strong network in sales
    • large-scale investment in LED luminaires and controls
    • brandname
  16. samsung electronics key advantages
    • stable supply of raw materials
    • 128 patents
  17. factors contributing to samsung electronics' advantages
    • Joint venture with Sumitomo Chemicals for stable supply of sapphire wafers
    • other branches of Samsung Electronics which need LED products, like LED TVs, Smartphones
    • advanced technologies in production process
  18. cree key advantage
    licensing program on remote phosphor technology
  19. GE lighting key advantages
    • patent on Tetra LED lighting system
    • Cooling technology
    • Halogen power supplies
    • leader in Nafta
  20. Osram key advantages
    • leader as supplier of automotive lamps and LED for vehicles
    • dominance in electronic control gear
  21. The region ... is expected to have sig. growth in LED market due to...
    Asia...rapid construction investment
  22. meaning of general lighting
    areas of applications including residential, office, shop, hospitality, industrial, outdoor and architectural
  23. LED market trend
    • OLED will be developed to replace LED
    • backlighting market will shrink and companies will shift their production for general lighting
    • Dropping Average Selling Price (ASP) of LED Components due to rapid adoptation
    • Broadening of LED Package Types
    • commercial/industrial and retail display will biggest segment by 2016
  24. facts about current market
    • the top component suppliers are from Asia
    • architectural lighting takes the largest share of LED lighting segmentation
    • incandescent lighting still dominant in residential segment
    • linear/CFL dominant in commercial segment
    • HID dominant in outdoor lighting segment
  25. LED value chain
    • wafer, chip, LED component, LED module
    • module+drive=engine
    • engine+secondary optics+heat sink=luminaire
  26. design issues of LED
    • • Dimming – lighting control gear.
    • • EMI issues – electromagnetic interference (EMI) of switching inverters affecting LED driver performance
    • • Heat – High thermal intensity. Thermal management to avoid high junction temperature. The heatsink is typically a significant proportion of the lamp cost.
    • • Power factor – Current and voltage not in phase and power factor correction is required.
    • • Phosphor – Use Phosphor to adjust lighting colour.
    • • Optics – LEDs emit over a relatively narrow solid angle compared to existing technologies
  27. types of intellectual property
    • design patterns
    • copyright
    • patent
    • Trade Secrets/Confidential Information
    • trade mark
  28. characteristics of patent
    • limited time
    • defined by patent claims
    • territorial
    • first file
    • license is revocable while assignment is irrevocable
  29. reasons for patent
    • licensing revenue
    • reduce competitors by frozing development of competing technologies
    • competitive advantage
    • asset creation

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