JPS62226555A - Electrode for cold cathode discharge lamp - Google Patents

Abstract

PURPOSE:To prevent a getter form being oxidized, by constituting an electrode so as not to cause heat to be irradiated to the getter at the time of its sealing. CONSTITUTION:A getter is designed so as to be installed in such a position as avoiding any heat by an electrode plate so as to receive no irradiation of heat attributable to an intense heat at the time of sealing. For example, the getter 2 deposited to each inner part of two electrode plates 1 oppositely set up receives no irradiation of heat at the time of sealing and is not oxidized as well, so that its adsorptivity of harmful gas for discharge is in no case damaged. Therefore, at the time of lighting a discharge lamp, the inside of a tubular bulb comes into a state of being easy to discharge by action of the getter 2. And, this electrode structure has such effects increasing a substantial ion collision area of the electrode palte 1 and also increasing an electron emission quantity, therefore discharge lamp starting voltage becomes lowered.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is applicable to a light source with a narrow tube diameter, such as a rear light source of a transmissive liquid crystal display device or a reading light source for @information equipment.

The present invention also relates to a light source that requires high brightness, especially its electrode.

[Conventional technology]

FIG. 2 shows a conventional electrode for a cold cathode discharge lamp, with (a) being a front view and (b) being a side view. In the figure, (11 is two 7'm nickel (hereinafter referred to as Ni) flat electrode plates arranged facing each other, and (2) is a nickel (hereinafter referred to as Ni) electrode plate welded to the outer surface of each of the two electrode plates (1).H2O A getter containing mercury that adsorbs gases harmful to discharge such as , Co, and H2, (3
ν is the Ni lead welded between the two electrode plates (1), and (4) is this Ni! A stem supporting the J-dore (31), (5) is an exhaust pipe provided on this stem (4).

(6) is a lead-in wire connected to the Ni lead (31).

Further, a cross-sectional view of a cold cathode discharge lamp using this electrode is shown in No. 3-. (7) is a tubular bulb in which the above-mentioned electrodes are hermetically sealed at both ends using high heat, and a rare gas is sealed inside. (8) is a phosphor coated on the inner surface of this tubular bulb (7).

Next, the ignition operation of this cold cathode discharge lamp will be explained. When an electric current is passed between the electrodes at both ends of the tubular bulb (7) through the lead-in wire (6), an initial plasma is generated inside the tubular bulb (7), and ions in this plasma are transferred to the electrode plate (1). The secondary electrons collide with the electrons and are emitted. Thus the tubular pulp (7
), the mercury atoms excited by the electron energy of the discharge emit all ultraviolet light due to resonance transition, and the excited phosphor (8) absorbs this ultraviolet light and emits visible light, which is used for illumination. It will be provided.

In the above-described operation, the electrode plate (1) is bombarded by ions at the initial stage of lighting the discharge lamp, and the temperature rises to about 800C.

Electricity 4 due to this high temperature? The getter (2) welded to the surface of the plate (1) exhibits a gas adsorption effect and adsorbs all the harmful gas to the minute amount of discharge remaining inside the tubular bulb (7), so no discharge occurs inside the bulb (7). It becomes easier to perform.

[Problem that the invention seeks to solve]

As mentioned above, the conventional electrode has a getter (21'z) on the outer surface of the electrode plate (11).In order to seal this electrode to both ends of the tubular pulp (7), a valve (7) is used. This heat is applied as radiant heat from the tubular pulp (7) to the getter (21) of the electrode configured as described above, and this getter (21) is oxidized.As a result.

When this discharge lamp lights up, getter +21 adsorbs gas and 7
There is a problem in that gas desorption due to ion attack and desorption of the getter oxide layer occurs, making it difficult to discharge inside the discharge lamp.

The object of the present invention is to obtain an electrode for a cold cathode discharge lamp that does not impair getter performance during electrode sealing.

[Means for solving problems]

The electrode for a cold cathode discharge lamp according to the present invention has a structure in which the getter is not irradiated with heat during electrode sealing.

[Effect]

In this invention, since the getter is not irradiated with heat during electrode sealing, oxidation of the getter is prevented.

〔Example〕

FIG. 1 is a side view showing an embodiment of the present invention. (1
1, (31, (41 is the same as the second factor conventional example. (2
The getter is welded to the inside of two electrode plates (1) placed opposite each other, and contains mercury that adsorbs gases harmful to discharge, such as H2O and COtH2.

The lighting operation of a discharge lamp similar to the 3-type LED using an electrode configured in this way is the same as that of the conventional example, but the electrode structure of the present invention prevents heat from being applied to the getter (2) during electrode sealing. Since it is not irradiated and not oxidized, its adsorption properties for harmful gases are not impaired. Therefore, when the discharge lamp is turned on, the inside of the tubular pulp (7) becomes easily discharged due to the action of the getter (21).In addition, this electrode structure increases the substantial ion collision area of the electrode plate (1), increasing the electron emission t. For these reasons, the discharge lamp starting voltage is lowered. For example, if a rare gas of Ne/Ar Q, 1% is placed inside a tubular bulb (7) with a bulb diameter of 8φ and a tube length of 300 m at a pressure of 10 to 50 Torr. In a cold cathode discharge lamp filled with several mercury, the starting voltage is 5o with conventional electrodes.
ov ~ 1.2KV, but with the electrode of the present invention, it was 2
A reduction in starting voltage of 0-40% was observed.

Note that the shape of the electrode is not limited to the above embodiment, and the shape of the electrode is not limited to the shape of the getter (2
It is sufficient if 1 has a shape that is not irradiated with heat.

〔Effect of the invention〕

As described above, in the present invention, the getter is not irradiated with heat during electrode sealing, so there is an effect that the performance of the getter is not impaired.

[Brief explanation of drawings]

FIG. 1 is a side view of an electrode for a cold cathode discharge lamp according to an embodiment of the present invention, and FIG. 2 is a side view of a conventional electrode for a cold cathode discharge lamp.
is a front view, (b) is a side view, and FIG. 3 is a cross-sectional view of a conventional cold cathode discharge lamp. (1) is an electrode plate, (2) a barge getter, (3I is Ni
Lead. (4) is the stem, (51 is the exhaust pipe, (61 is the lead-in line, (
7) is a tubular pallet 7', (81 is a phosphor. In the figure, (b) and numerals indicate the same or equivalent parts.

Claims (2)

[Claims] (1) The electrodes of the discharge lamp are formed by sealing electrodes to both ends of a tubular bulb using high heat, and the electrodes include an electrode plate and a getter provided on the electrode plate to adsorb gas harmful to the discharge;
An electrode for a cold cathode discharge lamp, characterized in that the getter is provided at a position avoided by the electrode plate so as not to be exposed to heat irradiation caused by high heat during the sealing. (2) The cold cathode discharge lamp according to claim 1, characterized in that the electrode plates are plate-shaped nickel electrode plates, two of these are provided facing each other, and a getter is welded to the inside of each electrode plate. electrode.