METHOD FOR MANUFACTURING COLD CATHODE ELEMENT, COLD CATHODE ELEMENT AND SEALING DEVICE OF COLD CATHODE ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a method for easily manufacturing a cold cathode element with high performance and long life at low cost, a cold cathode element obtained thereby, and a sealing device for the cold cathode element. SOLUTION: This sealing device comprises a vacuum chamber 41 and exhaust device 42 for exhausting and evacuating the sealed space of the cold cathode element, a pressurization control mechanism 43 for pressurizing a lid body 30 arranged in a through-hole 29 formed in a back plate 24, and an oscillator 44 for applying ultrasonic waves to either the lid body 30 or the back plate 24 so that the lid body 30 is closely fitted to the through-hole 29.