| 摘要 |
A light source comprises a phosphor layer excited to luminescence by electron bombardment from a field emission cathode. The field emission cathode comprises an elongate wire-shaped carrier with a cylindrical surface and a diameter of 0.5-5 mm. The cylindrical surface has conductive surface irregularities in the form of tips with a radial extension of less than 10 mum. A light source (10) comprises an evacuated container with walls (20). The walls comprise an outer glass layer (23) coated on the inside with a phosphor layer (24) forming a luminescent layer, and a conductive layer (25) forming an anode. The phosphor layer is excited to luminescence by electron bombardment from a field emission cathode (40) inside the container. The field emission cathode comprises an elongate wire-shaped carrier with a cylindrical surface and a diameter of 0.5-5 mm. A portion of the cylindrical surface is provided with conductive surface irregularities in the form of tips with a radial extension of less than 10 mum. |
