H01J2201/2821 - CPC Classification

Electrodes common to discharge tubes; Heaters for thermionic cathodes; Characterised by the shape or size Envelope or cross-section

• H01J2201/2825 » being oval or elliptic 0
• H01J2201/2828 » being rectangular or square 0
• H01J2201/2832 » being circular 0