H01J 2201/30
Cold cathodes
H01J2201/30 (Cold cathodes) appears on 1,872 US grants and 1,446 published applications in this corpus.
Search patents in H01J- Granted patents
- 1,872
- Published applications
- 1,446
- Assignees
- 512
- Inventors
- 2,622
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 1 | 0 |
| 1979 | 2 | 0 |
| 1980 | 0 | 0 |
| 1981 | 2 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 2 | 0 |
| 1985 | 1 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 0 | 0 |
| 1989 | 2 | 0 |
| 1990 | 4 | 0 |
| 1991 | 8 | 0 |
| 1992 | 13 | 0 |
| 1993 | 17 | 0 |
| 1994 | 26 | 0 |
| 1995 | 34 | 0 |
| 1996 | 76 | 0 |
| 1997 | 87 | 0 |
| 1998 | 116 | 0 |
| 1999 | 83 | 0 |
| 2000 | 93 | 0 |
| 2001 | 73 | 28 |
| 2002 | 88 | 118 |
| 2003 | 91 | 100 |
| 2004 | 110 | 144 |
| 2005 | 90 | 155 |
| 2006 | 92 | 149 |
| 2007 | 81 | 130 |
| 2008 | 75 | 98 |
| 2009 | 56 | 90 |
| 2010 | 95 | 82 |
| 2011 | 83 | 57 |
| 2012 | 55 | 35 |
| 2013 | 45 | 31 |
| 2014 | 31 | 21 |
| 2015 | 32 | 32 |
| 2016 | 32 | 21 |
| 2017 | 23 | 16 |
| 2018 | 19 | 11 |
| 2019 | 14 | 28 |
| 2020 | 27 | 11 |
| 2021 | 19 | 21 |
| 2022 | 15 | 19 |
| 2023 | 17 | 20 |
| 2024 | 16 | 14 |
| 2025 | 19 | 9 |
| 2026 | 3 | 6 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- H01J 2201/304Field emission cathodesIndexing code1,345
- H01J 2201/319Circuit elements associated with the emitters by direct integrationIndexing code311
- H01J 2201/316Having an electric field parallel to the surface thereofIndexing code255
- H01J 2201/312Having an electric field perpendicular to the surface thereofIndexing code51
- H01J 2201/306Ferroelectric cathodesIndexing code23
- H01J 2201/317Combined with other synergetic effectsIndexing code23
- H01J 2201/308Semiconductor cathodesIndexing code20
Recent patents
- Electron emission methods to generate electron beams with a narrow energy distribution25 Aug 2026US 12,719,005 B2The Regents of the University of California
- Emitter and field emission assembly including the same7 Jul 2026US 12,676,276 B2AweXome Ray, Inc.
- Systems and methods for fabricating silicon die stacks for electron emitter array chips26 May 2026US 12,640,326 B2
- Systems, devices, and methods for multisource volumetric spectral computed tomography2 Dec 2025US 12,487,193 B2The University of North Carolina at Chapel Hill
- Methods of forming a field emission cathode4 Nov 2025US 12,462,999 B2NCX Corporation
- X-ray devices with nanotube emitters and methods of forming8 Oct 2026US 2026/0311951 A1Varex Imaging Corporation
- Field emission device having automatic current limiter10 Sep 2026US 2026/0269165 A1LG Electronics Inc.
- Silicon carbide based triode electron emitter and producing an electron beam with same23 Jul 2026US 2026/0213110 A1
- Backend field emission devices19 Mar 2026US 2026/0081089 A1
- Carbon nanotube based cold cathodes for x-ray generation26 Feb 2026US 2026/0058086 A1Carestream Dental LLC
Most cited
By later US patents
- Electron source with micropoint emissive cathodes and display means by cathodoluminescence excited by field emission using said source400US 4,940,916 ACommissariat A L' Energie Atomique · 1990
- Self-oriented bundles of carbon nanotubes and method of making same326US 6,232,706 B1The Board of Trustees of the Leland Stanford Junior University · 2001
- Vertical microelectronic field emission devices312US 5,475,280 AMcnc · 1995
- Microelectronic and microelectromechanical devices comprising carbon nanotube components, and methods of making same295US 6,445,006 B1Advanced Technology Materials, Inc. · 2002
- Method to form self-aligned gate structures around cold cathode emitter tips using chemical mechanical polishing technology285US 5,229,331 AMicron Technology, Inc. · 1993