Patent ID: 9589784
Date: 2017-03-07
CPC Classifications: H01J

Claim:
1. An illuminant comprising; a gas volume contained in a glass bulb, said glass bulb forming a gas lighting chamber, an HF energy injection device for exciting the gas volume with surface waves and having a coupling structure which comprises a coaxial jacket, a front plate and a coupling slot for impressing the surface waves, said HF energy injection device further having a central conductor that is coupled into the gas volume, is isolated galvanically from the coupling structure and from the gas volume and is arranged on a longitudinal axis of the coaxial jacket, and said central conductor projecting beyond the coaxial jacket at a distance from the coupling structure, the central conductor in the region projecting beyond the coaxial jacket being located within the gas volume, in order therefore, during operation, to form a surface wave extending along the central conductor via the coupling structure of the coaxial HF energy injection device so as to set the gas volume into the plasma state.