Plasma Globe
The Plasma Globe was once known as “Inert GasDischarge Tube” named by inventor Nikola Tesla. What is inside a Plasma Globe? What is Plasma? Plasma is said to be the 4th state of matter since it does not consist of molecules like the other 3 states. A Plasma globe is a middle electrode sitting in a large vessel that contains inert gas. The gas MUST be inert or else it will react with the electrode surface. It must also be at low pressure in order to be able to break down a not-too-high voltage. The electrode is then energized with a high voltage frequency power supply. The high voltage breaks the gas down and the high frequency gets the current through the glass of the glove and into the surrounding air by capacitive coupling. Plasma is simply a gas that contains charged particles like electrons and ions. The electrons are broken free from a parent atom/molecule and that atom/molecule becomes an ion. The electron has a negative charge and the ion has a positive charge. When the charged particles move around within the plasma they change the local characteristics of the electro-magnetic field. This along with the oscillating electro-magnetic field from the electrode will excite ions.molecules, and atoms. When the particles become excited they will quickly radiate the energy in the form of a photon(unit of light). This is what makes the plasma emit it’s characteristic color, the color depends on the gas that it originated, and the temperature. The characteristics of how the electro-magnetic fields combine is what determines the overall appearance of the plasma globe. .What happens inside a plasma globe is the travel of electrons from the electrode to the outer surface and an oscillating electro-magnetic field.
The pressure in the globe will help determine the characteristics of the streamers. The pressure in a plasma globe is much higher than the pressure normally found in most plasma chambers used for scientific experiments. It has to be this high to be able to see the streamers. This is why it gets hot when plasma is generated. The hotter region has much high conductivity therefore the streamers remain intact until some sort of instability breaks them.