CAPACITORS

**Definition:** This place covers:

Passive two-terminal electrical components used to store energy in an electrical field, typically two electrical conductors, i.e. electrodes, separated by a dielectric or dielectric medium.

Non-electrolytic, fixed capacitors, per se, e.g. thin and thick film capacitors, details thereof, e.g. electrodes, dielectrics, housings and encapsulations, and structural combinations thereof with each other, e.g. stacked, multilayer, feed-through or anti-noise capacitors, or with electrolytic devices covered by this subclass, or with other electric elements not covered by this subclass where the structure consists mainly of a capacitor. Processes of manufacture thereof. H01G4/00 .

Non-electrolytic, variable capacitors per se, in which the capacitance is varied by mechanical means, e.g. using variation of effective area of electrode, using variation of distance between electrodes, e.g. capacitors making use of microelectromechanical systems (MEMS), or using multiple capacitors. Details thereof, and structural combinations thereof with each other, with electrolytic devices covered by this subclass, or with other electric elements not covered by this subclass where the structure consists mainly of a capacitor. Processes of manufacture thereof. H01G5/00 .

Non-electrolytic, variable capacitors per se, in which the capacitance is varied by non-mechanical means, e.g. electrets, ferroelectric capacitors. Details thereof, and structural combinations thereof with each other, with electrolytic devices covered by this subclass, or with other electric elements not covered by this subclass where the structure consists mainly of a capacitor. Processes of manufacture thereof. H01G7/00 .

Electrolytic capacitors per se, e.g. liquid, solid, electric double layer, hybrid or redox capacitors, details thereof, e.g. terminals, electrolytes, electrodes, housings, and processes of manufacture thereof. Electrolytic rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices per se, and details thereof. Structural combinations thereof with each other, with non-electrolytic capacitors or with other electric components not covered by this subclass. Processes of manufacture thereof. H01G9/00 .

Apparatus specially adapted for manufacturing capacitors; Processes specially adapted for manufacturing capacitors not provided for in other main groups of this subclass. H01G13/00 .

Structural combinations of capacitors or other devices covered by at least two different main groups of this subclass with each other. H01G15/00 .

Structural combinations of capacitors or other devices covered by at least two different main groups of this subclass with other electric elements, not covered by this subclass, e.g. RC combinations. H01G17/00 .Details common to two or more main types of devices covered by this subclass, e.g. special adaptation for mounting; cooling, heating and ventilating arrangements; housings, encapsulations and protection or prevention arrangements. H01G2/00 .

**Limiting references (this place does not cover):** - Selection of specified materials as dielectric -> H01B3/00 - Capacitors having potential barriers -> H10D1/62 , H10K10/10

**Glossary:** - collector: a conductive component in intimate contact with an electrode material in an electrolytic or electric double layer capacitor - electrolyte: an ionic conducting liquid or solid either comprised in one of the electrodes, typically the cathode, of an electrolytic capacitor or ensuring electric conduction between electrode active parts or electric double layers therein in Electric Double Layer Capacitors