generate an electric field of 1 v micron 20 v micron between the anode 202 and cathode 205 conductors such that electrons 208 are extracted from the cnt layer 204 and accelerated to the anode phosphor layer 203 the gap between the anode 212 and cathode 211 and the acceleration voltage used is dependent on the quality of the cnt material 204 used and the energy of electrons needed to activate the phosphor 203 efficiently typically electron energies of 5000v or higher are needed to efficiently activate the phosphor 10 000v is better above 10 000v 12 000v the phosphor efficiency will be even higher but x ray light may also be generated which may be harmful and thus may need to be avoided it may be possible to choose a glass material that blocks the x ray light but allows the uv light to pass in all cases the glass 201 of the anode 212 allows the uv light 209 to pass through in one embodiment the light passes through the anode glass 201 as shown but other configurations not shown may allow the light to pass through the cathode surface 206 and the anode surface is made reflective to pass as much light as possible through the cathode surface 206 in yet another configuration both the uv light may pass through both the anode and the cathode substrates in other words.