DISPLAY TUBE FOR LIGHT SOURCE

PURPOSE:To provide sufficiently high vacuum degree independently of enlargement of the surface area of a getter in a glass bulb and at the same time to surely prevent leakage occurrence and to improve the quality and the reliability of a display tube for a light source. CONSTITUTION:A display tube for a light source is composed of a display tube main body and a getter chamber 30; wherein the display tube main body is composed by air-tightly sealing a stem structure body 10, in which an anode 17 and a cathode structure body 14 are built, in a glass bulb structure 4 consisting of a front panel 2 and a phosphor face 5 formed in the inner face of the panel; and the getter chamber 30 is connected with the display tube main body through a gas discharging pipe 13 and contains a getter 33 in the inside. The getter chamber 30 works as a getter pump and an unnecessary gas in the glass bulb structure 14 is absorbed.