External electrode fluorescent lamp and method of fabricating the same
An external electrode fluorescent lamp is provided that includes a tube having electrode regions at end regions and a fluorescent region between the end regions. A phosphor layer is formed by dipping an open end of the tube into a solution containing phosphor material and permitting a capillary phenomenon to deposit the phosphor material on the inner surface of the tube in the corresponding electrode region and the fluorescent region. The phosphor material is then baked and the baked phosphor material in the electrode region is removed. A protection material is deposited on the phosphor layer and the inner surface of the tube and then baked to form a protection layer. One end is closed, a discharge gas filled in an inner space of the tube and the other end is then closed. External electrodes are then disposed on an outer surface of the tube in the electrode regions.
1 . An external electrode fluorescent lamp, comprising:
a tube having an electrode region at end regions, and a fluorescent region between the end regions;
a discharge gas filling an inner space of the tube;
a phosphor layer contacting an inner surface of the tube in the fluorescent region;
a protection layer covering the phosphor layer; and
external electrodes on an outer surface of the tube in the electrode regions.
2 . The lamp according to claim 1 , wherein the protection layer further contacts the inner surface of the tube in the electrode regions.
3 . The lamp according to claim 1 , wherein the protection layer comprises at least one of magnesium oxide (MgO), magnesium fluoride (MgF 2 ), indium-tin-oxide (ITO), yttrium oxide (Y 2 O 3 ), lithium fluoride (LiF), or calcium fluoride (CaF 2 ).
4 . The lamp according to claim 1 , wherein the tube comprises glass.
5 . The lamp according to claim 1 , further comprising closing means closing ends of the tube.
6 . The lamp according to claim 1 , wherein the discharge gas comprises at least one of mercury (Hg), neon (Ne), or argon (Ar).
7 . The lamp according to claim 1 , wherein the phosphor layer contacts substantially the entire inner surface of the tube in the fluorescent region.
8 . A method of fabricating an external electrode fluorescent lamp, the method comprising:
preparing a tube having openings at ends of the tube, the tube having electrode regions at end regions and a fluorescent region between the end regions;
forming a phosphor layer on an inner surface of the tube in the fluorescent region such that the phosphor layer contacts the inner surface of the tube in the fluorescent region;
forming a protection layer covering the phosphor layer;
filling an inner space of the tube with a discharge gas and closing the openings; and
forming external electrodes on an outer surface of the tube in the electrode regions.
9 . The method according to claim 8 , wherein the protection layer further contacts the inner surface of the tube in the electrode regions.
10 . The method according to claim 8 , wherein the protection layer comprises at least one of magnesium oxide (MgO), magnesium fluoride (MgF 2 ), indium-tin-oxide (ITO), yttrium oxide (Y 2 O 3 ), lithium fluoride (LiF), or calcium fluoride (CaF 2 ).
11 . The method according to claim 8 , wherein forming the phosphor layer includes:
dipping an open end of the tube into the phosphor material solution, thereby depositing the phosphor material on the inner surface of the tube in the corresponding electrode region and the fluorescent region through a capillary phenomenon;
baking the phosphor material; and
removing the baked phosphor material in the electrode region to form the phosphor layer.
12 . The method according to claim 8 , wherein forming the protection layer includes:
depositing a protection material on the phosphor layer and the inner surface of the tube; and
baking the protection material to form the protection layer.
13 . The method according to claim 8 , wherein filling the inner space of the tube with the discharge gas and closing the openings include:
closing at least one of the openings;
filling the inner space of the tube with the discharge gas; and
closing the remaining openings.
14 . The method according to claim 8 , wherein the tube comprises glass.
15 . The method according to claim 8 , wherein the discharge gas comprises at least one of mercury (Hg), neon (Ne) or argon (Ar).
16 . The method according to claim 8 , wherein the phosphor layer contacts substantially the entire inner surface of the tube in the fluorescent region.
17 . A method of fabricating an external electrode fluorescent lamp, the method comprising:
forming a phosphor layer directly on an inner surface of a tube in a fluorescent region from an electrode region of the tube to substantially an opposing electrode region of the tube and removing the phosphor layer from the one electrode region;
forming a protection layer covering the phosphor layer;
filling an inner space of the tube with a discharge gas and closing openings of the tube; and
forming external electrodes on an outer surface of the tube in the electrode regions.
18 . The method according to claim 17 , wherein the protection layer contacts the inner surface of the tube in the electrode regions.
19 . The method according to claim 17 , wherein forming the phosphor layer includes:
dipping an open end of the tube into the phosphor material solution, thereby depositing the phosphor material on the inner surface of the tube in the one electrode region and the fluorescent region through a capillary phenomenon;
baking the phosphor material; and
removing the baked phosphor material in the electrode region to form the phosphor layer.
20 . The method according to claim 17 , wherein forming the protection layer includes:
depositing a protection material on the phosphor layer and the inner surface of the tube; and
baking the protection material to form the protection layer.