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Field Emission Lamp



Field Emission Lamp Technology

Electron sources play an essential role in information display. They mostly use the thermionic emission mechanism, where electrons are emitted from heated filaments (hot cathodes). Field emission is an alternative mechanism to extract electrons.
It is a quantum effect where under a sufficiently high external electric field, electrons near the Fermi level can tunnel through the energy barrier and escape to the vacuum level. Compared to thermionic emission, this is a preferred mechanism for certain applications because no heating is required and the emission current is almost solely controlled by the external field.

The basic physics of field emission is well understood. The emission current from a metal surface is determined by the Fowler?Nordheim (F?N) equation: I = aV 2 exp(.b3/2/V ), where I, V, , are the emission current, applied voltage, work function, and field enhancement factor, respectively. For metal, with typical work function and a flat surface the threshold field is typically around 104 V/ m which is impractically high. The work function is a basic material property that cannot be varied significantly. All the field emission sources rely on field enhancement due to sharp tips/protrusions, so they tend to have smaller virtual source sizes because of the primary role of the factor. The larger the , the higher the field concentration, and therefore the lower the effective threshold voltage for emission

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Structure of FE Lamp


Therere 2 core components in the FE lamp. FE uses the cold cathode of Graphite type of carbon nano-tube. It is important to develop the high-efficiency cathode and our Carbon Nano Cathod (CNC) is the optimized one for the best performance. The cathode can be commercially mass-produced at lower than 400 in the CVD chamber. FE also requires carefully designed phosphors for each emission application of light wavelength. Our phosphors are generating very narrow pick of target wavelength at the highest intensity.
VALLOY and SUN RISE Technical corp. (HK) is developing the lamp together currently. ZAO SPF Luminophor (Russia) is providing the optimized phosphors for the project.

 


Features of FE Lamp

Main features of FE lamp can be summarized as (1) semi-permanent lifetime of CNC, (2) very high energy efficiency (30%) by direct emission mechanism without any gas, (3) flexible control of light wavelength from UR to UV by adjusting phosphors, (4) easy production and application, (5) very fast response time which is suitable multimedia display application (FED), and (6) flexible manufacturing in any shape and any size. FE technology can be applied to various fields from general white light lamps to professional UV lamps and multimedia display panels.

 
  FE CCFL OLED EL Halogen Lamp
Energy Efficiency
30%
10%
7%
1-3 ?
15%
Problem
Diffidult cathod development
Hg-Mercury limit of color wavelength Weak
weather-proof
slow lighting-up
Power Consumption(5,000cd"E)
0.5-1.0 W 30-40 W
10-20 W
10-20 W
100-200 w
Life time
0,000
100,000h
20,000-30,000h
30,000- 50,000h 5,000- 10,000h 20,000- 30,000h
Power Consumption (200,000cd"E)
W 500 W 200 W 200 W 2000 W
Life
50,000h 10,000h 30,000h 5,000h 10,000h
Feature
non-heating, non-gas
       

Address : Rm 1017, Daemyung Valeon, 127 Beobwon-ro, Songpa-gu, Seoul, 05836. Rep. of KOREA.
Tel : +82-2-6082-5022 Fax : +82-2-445-5441 Email : support@valloy.net
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