| 摘要 |
The light source, comprises an evacuated container having walls, including an outer glass layer (23) which on at least part thereof is coated on the inside with a layer of phosphor (24) forming a luminescent layer and a conductive layer (25) forming an anode. The phosphor (24) is excited to luminescence by electron bombardment from a field emission cathode (40) located in the interior of the container. The field emission cathode (40) comprises a carrier having a diameter in the mm range. At least a portion of the surface of the carrier is provided with a conductive layer having surface irregularities in the form of tips, having a radial extension being less than about 10 mum. Due to the geometry and the tips, the electric field is concentrated and amplified at the field emission surface. |
