H01J 3/02
Electron guns
H01J3/02 (Electron guns) appears on 1,105 US grants and 633 published applications in this corpus.
Search patents in H01J- Granted patents
- 1,105
- Published applications
- 633
- Assignees
- 388
- Inventors
- 1,677
- Latest grant
- 24 Mar 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 12 | 0 |
| 1977 | 2 | 0 |
| 1978 | 4 | 0 |
| 1979 | 3 | 0 |
| 1980 | 3 | 0 |
| 1981 | 1 | 0 |
| 1982 | 8 | 0 |
| 1983 | 0 | 0 |
| 1984 | 2 | 0 |
| 1985 | 6 | 0 |
| 1986 | 4 | 0 |
| 1987 | 13 | 0 |
| 1988 | 11 | 0 |
| 1989 | 10 | 0 |
| 1990 | 10 | 0 |
| 1991 | 16 | 0 |
| 1992 | 18 | 0 |
| 1993 | 26 | 0 |
| 1994 | 22 | 0 |
| 1995 | 23 | 0 |
| 1996 | 43 | 0 |
| 1997 | 39 | 0 |
| 1998 | 68 | 0 |
| 1999 | 77 | 0 |
| 2000 | 64 | 0 |
| 2001 | 42 | 12 |
| 2002 | 56 | 47 |
| 2003 | 46 | 40 |
| 2004 | 40 | 48 |
| 2005 | 33 | 67 |
| 2006 | 35 | 61 |
| 2007 | 28 | 46 |
| 2008 | 33 | 16 |
| 2009 | 33 | 25 |
| 2010 | 23 | 20 |
| 2011 | 21 | 19 |
| 2012 | 19 | 16 |
| 2013 | 17 | 34 |
| 2014 | 23 | 26 |
| 2015 | 27 | 24 |
| 2016 | 26 | 16 |
| 2017 | 14 | 12 |
| 2018 | 9 | 10 |
| 2019 | 14 | 20 |
| 2020 | 22 | 11 |
| 2021 | 10 | 18 |
| 2022 | 15 | 11 |
| 2023 | 6 | 15 |
| 2024 | 10 | 7 |
| 2025 | 17 | 6 |
| 2026 | 1 | 6 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- H01J 3/021Electron guns using a field emission, photo emission, or secondary emission electron812
- H01J 3/027Construction of the gun or parts thereof108
- H01J 3/025Electron guns using a discharge in a gas or a vapour as57
- H01J 3/029Schematic arrangements for beam forming46
- H01J 3/024Electron guns using thermionic emission of cathode heated by electron or ion21
- H01J 3/026Eliminating deleterious effects due to thermal effects, electric or magnetic field20
- H01J 3/023Electron guns using electron multiplication13
- H01J 3/028Replacing parts of the gun12
Recent patents
- Emitter and device comprising same24 Mar 2026US 12,586,747 B2Denka Company Limited
- Charged particle gun and charged particle beam system11 Nov 2025US 12,469,664 B2Hitachi High-Tech Corporation
- Electron beam devices with semiconductor ultraviolet light source21 Oct 2025US 12,451,314 B2Gaska Consulting, LLC
- Method for use with a radiotherapy device26 Aug 2025US 12,397,176 B2Elekta Limited
- Electron beam applicator, and electron beam emission method in electron beam applicator15 Jul 2025US 12,362,128 B2Photo electron Soul Inc.
- Transport Package for Charged Particle Gun and Maintenance Method for Charged Particle Gun20 Aug 2026US 2026/0245824 A1Hitachi High-Tech Corporation
- Field emission source for ion mobility spectrometry23 Jul 2026US 2026/0210910 A1Verily Life Sciences LLC
- Electron emission source18 Jun 2026US 2026/0171342 A1Infovion Inc.
- Electron source7 May 2026US 2026/0128249 A1Kabushiki Kaisha Toshiba
- Electron beam devices with semiconductor ultraviolet light source19 Feb 2026US 2026/0051451 A1Gaska Consulting, LLC
Most cited
By later US patents
- Split collector vacuum field effect transistor357US 5,012,153 A1991
- Vertical microelectronic field emission devices312US 5,475,280 AMcnc · 1995
- Cylindrical electron beam generating/triggering device and method for generation of electrons228US 7,122,949 B2Neocera, Inc. · 2006
- Electron emission device215US 4,904,895 ACanon Kabushiki Kaisha · 1990
- Field emission device160US 4,663,559 A1987