Electron emitting filaments for electron discharge devices

Patent · Fri Jan 01 00:00:00 EST 1988

OSTI ID:866656

Leung, Ka-Ngo ^[1]; Pincosy, Philip A ^[2]; Ehlers, Kenneth W ^[3]

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1. Hercules, CA
2. Oakland, CA
3. Alamo, CA

Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600.degree. C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for non-uniform current distribution along the filament due to the emission of electrons from the filament.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• DOE Contract Number: AC03-76SF00098
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4760306
• OSTI ID: 866656
• Country of Publication: United States
• Language: English

Related Subjects

electron
emitting
filaments
discharge
devices
electrons
copiously
emitted
device
comprising
loop-shaped
filament
lanthanum
hexaboride
directly
heated
electrical
current
produced
power
supply
connected
terminal
legs
produce
diamond
cut
slice
bar
shape
loop
rectangular
u-shaped
hairpin-shaped
zigzag-shaped
circular
provide
emission
relatively
operating
temperature
1600
degree
achieve
uniform
heating
formed
section
tapered
opposite
compensate
non-uniform
distribution
due
current produced
electron emitting
electron discharge
uniform heating
electron emission
discharge device
power supply
electrical current
operating temperature
device comprising
lanthanum hexaboride
directly heated
form cu
current distribution
uniform heat
uniform current
discharge devices
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