Patent US3614422A successfully refreshed from Google Patents.
US3614422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surge reduction resistors between a high-voltage source and an electron microscope electron gun
Assignee: Hitachi Ltd
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Filing: 1970-07-28
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Granted: 1971-10-19
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Expires: 1990-07-28
Abstract
Abstract A resistance for adjusting the bias voltage is provided in a high voltage source, a high DC voltage being applied to the resistance, and the high DC voltage and bias voltage are applied to the filament and Wehnelt electrode, respectively, of an electron gun in an electron microscope through a high-voltage cable including two core lines whose resistance value is high enough to reduce surge voltage.
Inventors
- 👤 Isao Matsui
- 👤 Yoshihisa Minamikawa
- 👤 Shinjiro Katagiri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:33
CPC Classifications
H; H01; H01B; H01B11/00; H01B11/18; H01B11/20; H01B11/206; H01J; H01J37/00; H01J37/02; H01J37/24; H01J37/243; H01J37/248
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
121 words
Apparatus for supplying high voltage from a high-voltage source to an electron gun in an electron microscope and the like comprising a high-voltage source having high DC-voltage-producing means and a variable bias resistance connected to said high DCvoltage-producing means for producing an adjustable bias voltage; a high-voltage cable including at least two core lines therein, the impedance of each said core line being larger than the surge impedance; and an electron beam device having an electron gun composed of a filament, a Wehnelt electrode and an anode, said filament being connected to said high DC-voltage-producing means through one of said two core lines and said Wehnelt electrode being connected to said bias resistance through the other of said two core lines.
Claim 2
Dependent Claim
121 words
Apparatus for supplying high voltage from a high-voltage source to an electron gun in an electron microscope and the like comprising a high-voltage source having high DC-voltage-producing means and a variable bias resistance connected to said high DCvoltage-producing means for producing an adjustable bias voltage; a high-voltage cable including at least two core lines therein, the impedance of each said core line being larger than the surge impedance; and an electron beam device having an electron gun composed of a filament, a Wehnelt electrode and an anode, said filament being connected to said high DC-voltage-producing means through one of said two core lines and said Wehnelt electrode being connected to said bias resistance through the other of said two core lines.
Claim 3
Dependent Claim
16 words
Apparatus according to claim 1, wherein said high-voltage cable comprises at least two coaxial core lines.
Claim 4
Dependent Claim
16 words
Apparatus according to claim 2, wherein said coaxial core lines are covered by a conductive member.
References Cited (Backward Citations)
US2424791A
Cited
US3227983A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |