CPC Main Group
H01J 21/00 Vacuum tubes (H01J25/00, H01J31/00 - H01J40/00, H01J43/00, H01J47/00, H01J49/00 take precedence; details of vacuum tubes H01J19/00)
4 direct subcodes
Child Classifications
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- H01J 21/02 Tubes with a single discharge path
- H01J 21/20 Tubes with more than one discharge path; Multiple tubes, e.g. double diode, triode-hexode
- H01J 21/34 Tubes with electrode system arranged or dimensioned so as to eliminate transit-time effect (with flat electrodes H01J21/36)
- H01J 21/36 Tubes with flat electrodes, e.g. disc electrode
Top Applicants
Top 10 applicants by patent filingsfor class H01, 2013–2023, worldwide · Source: EPO PATSTAT
- SAMSUNG ELECTRONICS COMPANY KR 37,897
- TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY TW 36,116
- APPLIED MATERIALS US 21,640
- LG ENERGY SOLUTION KR 20,770
- LG CHEM KR 19,835
- TOKYO ELECTRON JP 18,519
- ROBERT BOSCH DE 14,595
- INTEL CORPORATION US 13,580
- MURATA MANUFACTURING COMPANY JP 12,151
- SAMSUNG SDI COMPANY KR 12,080