Dual external electrode fluorescent lamp and manufacturing method thereof

A manufacturing method of a dual external electrode fluorescent lamp characterized by comprising:

• (i) a step of providing a 1st glass tube that has both ends opened thereof and an inner wall thereof coated with a fluorescent material, wherein the diameter thereof is homogeneous;
• (ii) a step of mutually connecting the 1st glass tube with two 2nd glass tubes by joining both opened ends of the 1st glass tube to the two both-end opened 2nd glass tubes that include opened ends thereof and have a diameter larger than that of the 1st glass tube;
• (iii) a step of joining 1st multi-tube for the enlargement of an electrode area in the one 2nd glass tube or a ‘flare’ structure having one closed end to one end of one 2nd glass tube through insertion after spreading one end widely, and a step of enlarging an electrode area in the other 2nd tube and joining a 2nd multi-tube having an exhaust port to the other 2nd tube through insertion;
• and
• (iv) a step of cutting and sealing a portion of the exhaust port after vacuumizing the inside of the glass tubes and injecting discharge gas inside the glass tubes through the connection of an exhaust system to the exhaust port.

A manufacturing method of a dual external electrode fluorescent lamp characterized by comprising:

• (i) a step of providing a 1st glass tube that has both ends opened thereof and an inner wall thereof not coated with a fluorescent material, wherein the diameter of the opened ends is not extended;
• (ii) a step of mutually connecting the 1st glass tube with two 2nd glass tubes by joining both opened ends of the 1st glass tube to the two both-end opened 2nd glass tubes that include opened ends thereof and have a diameter larger than that of the 1st glass tube;
• (iii) a step of coating a fluorescent material as the 1st glass tube and the two 2nd glass tubes are joined;
• (iv) a step of removing the fluorescent material at any one of the two joined 2nd glass tubes;
• (v) a step of joining 1st multi-tube for the enlargement of an electrode area in the one 2nd glass tube or a ‘flare’ structure having one closed end to one end of one 2nd glass tube through insertion after spreading one end widely, and a step of enlarging an electrode area in the other 2nd tube and joining a 2nd multi-tube having an exhaust port to the other 2nd tube through insertion;
• and
• (vi) a step of cutting and sealing a portion of the exhaust port after vacuumizing the inside of the glass tubes and injecting discharge gas inside the glass tubes through the connection of an exhaust system to the exhaust port.