H01J 25/00
Transit-time tubes
Official title: Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons (details of transit-time tubes H01J23/00; particle accelerators H05H)
H01J25/00 (Transit-time tubes) appears on 791 US grants and 478 published applications in this corpus.
Search patents in H01J- Granted patents
- 791
- Published applications
- 478
- Assignees
- 279
- Inventors
- 1,116
- Latest grant
- 8 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 14 | 0 |
| 1977 | 8 | 0 |
| 1978 | 11 | 0 |
| 1979 | 5 | 0 |
| 1980 | 13 | 0 |
| 1981 | 10 | 0 |
| 1982 | 6 | 0 |
| 1983 | 21 | 0 |
| 1984 | 8 | 0 |
| 1985 | 22 | 0 |
| 1986 | 17 | 0 |
| 1987 | 13 | 0 |
| 1988 | 16 | 0 |
| 1989 | 13 | 0 |
| 1990 | 14 | 0 |
| 1991 | 13 | 0 |
| 1992 | 16 | 0 |
| 1993 | 15 | 0 |
| 1994 | 16 | 0 |
| 1995 | 10 | 0 |
| 1996 | 22 | 0 |
| 1997 | 13 | 0 |
| 1998 | 14 | 0 |
| 1999 | 13 | 0 |
| 2000 | 7 | 0 |
| 2001 | 9 | 5 |
| 2002 | 15 | 14 |
| 2003 | 15 | 14 |
| 2004 | 14 | 32 |
| 2005 | 16 | 20 |
| 2006 | 26 | 18 |
| 2007 | 15 | 52 |
| 2008 | 15 | 25 |
| 2009 | 27 | 26 |
| 2010 | 27 | 13 |
| 2011 | 19 | 26 |
| 2012 | 21 | 25 |
| 2013 | 21 | 18 |
| 2014 | 33 | 20 |
| 2015 | 31 | 15 |
| 2016 | 17 | 14 |
| 2017 | 22 | 18 |
| 2018 | 10 | 11 |
| 2019 | 30 | 19 |
| 2020 | 13 | 15 |
| 2021 | 12 | 14 |
| 2022 | 9 | 18 |
| 2023 | 12 | 12 |
| 2024 | 16 | 10 |
| 2025 | 11 | 16 |
| 2026 | 5 | 8 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- H01J 25/02Tubes with electron stream modulated in velocity or density in a modulator294
- H01J 25/50Magnetrons, i.e. tubes with a magnet system producing an h-field crossing the247
- H01J 25/34Travelling-wave tubes180
- H01J 25/005Gas-filled transit-time tubes12
- H01J 25/74Tubes specially designed to act as transit-time diode oscillators12
- H01J 25/76Dynamic electron-multiplier tubes10
- H01J 25/78Tubes with electron stream modulated by deflection in a resonator9
- H01J 25/61Hybrid tubes, i.e. tubes comprising a klystron section and a travelling-wave section2
All 12 subgroupsShow fewer
- H01J 25/68Tubes specially designed to act as oscillator with positive grid and retarding2
- H01J 25/62Strophotrons, i.e. tubes with h-field crossing the e-field and functioning with plural0
- H01J 25/64Turbine tubes, i.e. tubes with h-field crossing the e-field and functioning with0
- H01J 25/66Tubes with electron stream crossing itself and thereby interacting or interfering with0
Recent patents
- Klystrons and medical electron linear accelerators8 Sep 2026US 12,731,751 B2Shanghai United Imaging Healthcare Co., Ltd.
- Power supply device for gyrotron and power control method1 Sep 2026US 12,725,752 B2Kyoto Fusioneering Ltd.
- Inspection system and method23 Jun 2026US 12,663,388 B2Nuctech Company Limited
- Radiotherapy device and microwave source thereof12 May 2026US 12,623,089 B2Shanghai United Imaging Healthcare Co., Ltd.
- Magnetron10 Feb 2026US 12,548,729 B2Hitachi Power Solutions Co., Ltd.
- Electron tube6 Aug 2026US 2026/0229442 A1Nisshinbo Micro Devices Inc.
- Cathode and manufacturing method thereof23 Jul 2026US 2026/0213111 A1Shanghai United Imaging Healthcare Co., Ltd.
- Electromagnetic radiation generation2 Jul 2026US 2026/0188529 A1United Kingdom Atomic Energy Authority
- Observation unit, traveling wave tube unit, microwave tube unit, and observation method11 Jun 2026US 2026/0162922 A1NEC Network and Sensor Systems, Ltd.
- Insulative assemblies, microwave vacuum tube assemblies and radiotherapy machines including the same23 Apr 2026US 2026/0108764 A1Varian Medical Systems, Inc.
Most cited
By later US patents
- Mode suppression means for gyrotron cavities237US 4,398,121 AVarian Associates, Inc. · 1983
- Wide-band gyrotron traveling-wave amplifier229US 4,533,875 A1985
- Mode suppressors for whispering gallery gyrotron229US 4,851,788 AVarian Associates, Inc. · 1989
- Couplers for extracting RF power from a gyrotron cavity directly into fundamental mode waveguide229US 5,015,914 AVarian Associates, Inc. · 1991
- Gyrotron having a quasi-optical mode converter225US 5,187,409 AKabushiki Kaisha Toshiba · 1993