JP2002056805A - Fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent lamp wherein illuminance is improved and light blink is reduced. SOLUTION: This lamp has a glass bulb 10 coated with a phosphor 11; a rare gas sealed in the glass bulb 10 such that a total pressure P (Pa) satisfies relation of P(0.4a+b+1.8c)=210-280 (Pa) in the case of Ne:Ar:Kr=a:b:c (a+b+c=1) in a mole ratio; mercury sealed in the glass bulb 10; a pair of stems 13 sealing both ends of the glass bulb 10; a pair of leads 14 airtightly penetrating each the stems 13, through which a lamp current of 300-700 mA flows; triple coils 15 each electrically connected between the leads 14 pair, each having a main wire second pitch of 1.0-1.5 mm and a cold resistance of 1.8-8.0 Ω; an electron emissive material held by the triple coils 15; and a base member 16 installed in an end part of the glass bulb 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp having improved illuminance and reduced light flicker.

[0002]

2. Description of the Related Art Conventionally, as a method of improving the luminous flux of a fluorescent lamp, for example, a method of extending a discharge length or reducing a pressure of a sealed gas is known.

However, in order to extend the discharge length in order to improve the luminous flux as expected, the length of the glass bulb must be greatly increased and the mount height must be extremely reduced. Required.

[0004] Further, when the sealing pressure of a rare gas such as argon or krypton sealed in a fluorescent lamp is reduced, the amount of evaporation of the electron-emitting substance (emitter) applied to the electrodes is increased and the lamp life is shortened. However, there is a limit to the decrease in the sealing pressure.

On the other hand, a fluorescent lamp emits stable light by anodic vibration described later. Particularly, in a fluorescent lamp having a low input power, the anodic vibration is not easily performed.
There is a problem that light flicker easily occurs.

Hereinafter, the flicker of light of the fluorescent lamp will be described. In order to start the lighting of the fluorescent lamp, first, the electrodes are preheated to emit thermoelectrons from the electron-emitting substance. At this time, a predetermined voltage is applied between the pair of electrodes,
The thermoelectrons on the cathode side are accelerated in the direction of the opposite electrode (anode) to start discharge, excite mercury electrons in the glass bulb to generate ultraviolet light with a wavelength of 254 nm, and excite the phosphor to emit visible light. generate.

In the discharge process, near the electrodes, electrons are emitted from the electrodes during the cathode cycle, and electrons are incident on the electrodes during the anode cycle. However, anode oscillation occurs in the anode cycle.

That is, in the anode cycle, electrons are accelerated by the anode drop voltage and reach the anode surface with large energy. It collides with mercury atoms near the electrodes, causing excessive ionization. As a result, the electron density increases near the anode, and the anode drop voltage temporarily becomes zero, but thereafter, the electrons gradually diffuse and the electron density decreases. When the electron density decreases to a predetermined level, an anode drop voltage is generated again, and the electrons are accelerated to increase the electron density. This cycle is called “anode vibration”, and the vibration is repeated at a cycle of several kHz.

In a state where the anode vibration is generated stably, light is emitted from the fluorescent lamp in a relatively stable state. However, when the anode vibration is generated and extinguished irregularly, the light is emitted from the fluorescent lamp. The generated light will flicker.

The cause of the elimination of the anode vibration is that mercury ions ionized by the accelerating electrons in the anode cycle accumulate in the inner space surrounded by the last turn of the coil, and the mercury ions supplement the electrons reaching the anode surface. This is considered to be because the electron current is dispersed and flows into the entire coil, and the electron density is hardly increased by the anode drop voltage. If the anode vibration repeats generation and extinction, flickering occurs due to the pulsation of the lamp current, and it is known that low-wattage fluorescent lamps are particularly prominent, so improvement has been desired.

A fluorescent lamp using a triple coil is disclosed in Japanese Patent Application Laid-Open No. 1-225058, but there is no disclosure about the second pitch and the cold resistance of the main wire, and the flicker of light is reduced. No improved product has been produced.

[0012]

As described above, there is a demand for improving the illuminance in the conventional fluorescent lamp and improving the flickering of the light by stably generating the anode vibration especially in the low-output fluorescent lamp. It had been.

The present invention has been made in order to solve such a conventional problem, and an object of the present invention is to provide a fluorescent lamp in which illuminance is improved and light flicker is improved without impairing life characteristics.

[0014]

According to a first aspect of the present invention, there is provided a fluorescent lamp comprising: a glass bulb having an inner surface coated with a phosphor; and a molar ratio of Ne: Ar: Kr = a: b:
When c (a + b + c = 1), the total pressure P (Pa) is P (0.
4a + b + 1.8c) = a rare gas sealed so as to satisfy a relationship of 210 to 280 (Pa); mercury sealed in the glass bulb; and a pair sealing both ends of the glass bulb. A pair of leads through which the lamp current of 300 to 700 mA flows airtightly through each stem; electrically connected between each pair of the leads, and a second pitch of the main wire is 1.0 to 1.0. 1.5m
m, a triple coil having a cold resistance of 1.8 to 8.0 Ω; an electron-emitting substance held by the triple coil; and a base member attached to an end of the glass bulb. Features.

In the present invention, the molar ratio is Ne: Ar: K
When r = a: b: c (a + b + c = 1), the total pressure P (P
a) is P (0.4a + b + 1.8c) = 210-280
The reason why (Pa) is defined is that when the total pressure P (Pa) exceeds the above range, there is a problem that the light output decreases, and when the total pressure P (Pa) falls below the above range, the amount of the electron-emitting substance lost by evaporation is reduced. This is because there is a problem that the lamp life is shortened. Here, the electrode life of the lamp is determined by the diffusion and evaporation of the evaporated electron-emitting substance, and the diffusion rate is said to be almost inversely proportional to the product of the molecular weight of the sealed gas and the gas pressure.

A specific description will be given using the above relational expression. For example, a rare gas mixed at a molar ratio of 30% Ne (neon), 70% Ar (argon), and 0% Kr (krypton) is used. In the case, P (0.4 × 0.3 +
0.7 + 1.8 × 0) = 210-280 (Pa), and P = 210 / 0.82-280 / 0.82 = 256
The rare gas mixed at ３４341 (Pa) is sealed.

Further, for example, as a rare gas to be enclosed, A
The above P (0.4
a + b + 1.8c) = 210-280 (Pa) can be used, and P (0.4 × 0 + 1 + 1.8 × 0)
= 210-280 (Pa), and P = 210-280
Ar is enclosed in (Pa). In this case, 240
It is more preferable to enclose Ar at 280 (Pa).

Next, the reason why the second pitch of the main wire of the triple coil of the electrode is limited to 1.0 to 1.5 mm and the cold resistance is limited to 1.8 to 8.0 Ω will be described.

The triple coil used in the fluorescent lamp of the present invention is manufactured, for example, as follows.

That is, as shown in FIG. 1, a main wire 2 made of tungsten is attached to a first mandrel wire 1 made of molybdenum, and a sub-wire 3 made of thinner tungsten is wound thereon. Next, as shown in FIG. 2, the first wire
Is wound on a second mandrel wire 4 thicker than the first mandrel wire 1 made of molybdenum. Further, the first mandrel wire 1 and the main wire 2 wound on the second mandrel wire 4 and the sub-wire 3 are wound together with the second mandrel wire 4 are thicker than the second mandrel wire 4 made of molybdenum. 3 is wound around the mandrel wire 5 (this winding is referred to as “final turn”). Thereafter, the first to third mandrel wires are dissolved by treating with an acid that dissolves molybdenum but does not dissolve tungsten, thereby obtaining a triple coil 6 as shown in FIG.

The triple coil used in the present invention is not limited to those described with reference to FIGS. 1 to 3, but may have another configuration as long as it functions similarly to the present invention. .

In the triple coil of the present invention, the second pitch of the main wire (P2 shown in FIG. 3) is 1.0 to 1.5.
mm, more preferably 1.1 to 1.3 mm. Also, by using a tungsten wire thinner than a normal main wire for the main wire, or by narrowing the pitch or making the mandrel wire thicker and increasing the length of the main wire 2, the cold resistance is lower than that of the normal main wire. It has a high resistance of 1.8 to 8.0Ω.

In the present invention, the second pitch of the main wire of the triple coil is set to 1.0 to 1.5 mm. If the pitch is narrower than 1.0 mm, mercury ions hardly diffuse from gaps in the coil, and This is because mercury ions stay in the small space surrounded by the turn, the anode vibration disappears, and the generation and extinction are repeated, so that flicker tends to occur. This is because the overall length of the wire becomes short, the cold resistance becomes low, and it becomes difficult to secure a required amount of the electron emitting material.

In the present invention, the cold resistance is set to 1.8 to
The reason why the resistance is set to 8.0Ω is that when the cold resistance is lower than 1.8Ω,
This is because the anodic current moves discontinuously between the central portion and the end portion of the triple coil, and flicker easily occurs. On the other hand, if the cold resistance is higher than 8.0Ω, the electrode temperature becomes too high due to electrode preheating at the time of startup when used in combination with a starter type circuit or at the time of lighting when combined with an electronic ballast, resulting in electron emission. This is because the evaporation amount of the substance is increased and the lamp life is shortened.

On the surface of the triple coil of the present invention, the triple coil is immersed in a slurry with a carbonate of a substance mainly containing barium carbonate, strontium carbonate, calcium carbonate or zirconium carbonate and acting as an electron-emitting substance. And then dried to apply the carbonate. The carbonate of the substance adhered to the surface of the triple coil decomposes when a current flows through the triple coil to become an oxide, which acts as an electron-emitting substance.

The present invention is also directed to a fluorescent lamp having a lamp current of 300 to 700 mA flowing through the lead. The fluorescent lamp having a lamp current of 300 to 700 mA specifically means, for example, a lamp current of 300 to 450 m
A FL20 (straight pipe 20W), FCL32 (annular type 32)
W), FCL40 (annular type 40W) fluorescent lamp, and FL30 (straight tube 30) having a lamp current of 500 to 700 mA.
W) and FCL30 (annular type 30W) fluorescent lamps.

A fluorescent lamp according to a second aspect is the fluorescent lamp according to the first aspect, wherein the lamp current is 300 to 450.
mA, and the cold resistance is 5.0 to 8.0 Ω.

Here, the lamp current is 300 to 450.
The fluorescent lamp of mA specifically refers to FL as described above.
20 (straight pipe 20W), FCL32 (annular type 32W), F
A fluorescent lamp of CL40 (annular type 40W) is exemplified.
Among the fluorescent lamps having a lamp current of 300 to 450 mA, a fluorescent lamp of a straight tube 20 W having a current of 300 to 370 mA is more suitable.

The reason that the cold resistance is specified to be 5.0 to 8.0 Ω is that the lamp current is 30
This is because a more effective effect can be obtained at 0 to 450 mA. Further, the cold resistance is more preferably 5.5 to 6.5Ω.

A third aspect of the present invention is the fluorescent lamp according to the first aspect, wherein the lamp current is 500 to 700.
mA, and the cold resistance is 1.8 to 5.0Ω.

Here, the lamp current is 500 to 700 mA.
Is a FL30 as described above.
(Straight pipe 30W) and FCL30 (annular 30W) fluorescent lamps.

The reason that the cold resistance is specified to be 1.8 to 5.0Ω is that the lamp current is 50
This is because a more effective effect can be obtained at 0 to 700 mA. Further, the cold resistance is more preferably 2.6 to 4.0Ω.

A fluorescent lamp according to a fourth aspect is the fluorescent lamp according to the second aspect, wherein the mass of the electron-emitting substance is:
3.8 to 7.0 mg.

Here, the mass of the electron-emitting substance refers to the mass of the oxide of the substance that acts as the electron-emitting substance and is held in the triple coil. Therefore, in order to hold 3.8 to 7.0 mg, preferably 3.8 to 6.0 mg, of an oxide of a substance acting as an electron-emitting substance in the triple coil, it is necessary to use a carbonate having a larger mass than the substance. Activate by holding an appropriate amount.

A fluorescent lamp according to a fifth aspect is the fluorescent lamp according to the third aspect, wherein the mass of the electron-emitting substance is 4.5.
〜8.0 mg.

A fluorescent lamp according to a sixth aspect of the present invention is the fluorescent lamp according to any one of the first to fifth aspects, wherein the triple coil is extended and connected to the pair of leads. And

Here, the expression that the triple coil is elongated means that even when the second pitch of the main wire is not within the range of 1.0 to 1.5 mm at the time of manufacturing the triple coil, the triple coil is extended. By extending, the second pitch of the main wire is 1.0 to 1.5 m
m.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a fluorescent lamp according to a first embodiment of the present invention will be described.

In the first embodiment, the lamp current is 30
0 to 450 mA, specifically, 300 to 370 mA straight pipe 20W (FL20S / 18: Toshiba Lighting & Technology Corporation)
The description will be made using a fluorescent lamp manufactured by Toshiba.

FIG. 4 is a partial sectional view schematically showing the fluorescent lamp according to the first embodiment with a part omitted.

In FIG. 1, a fluorescent film 11 is applied to the inner surface of a glass bulb 10, a rare gas and mercury are sealed therein, and both ends thereof are sealed with a pair of stems 13.

A pair of leads 14 as inner wells (lead wires) which are hermetically sealed to the stems 13 are provided inside the stems 13, and a main wire of the main wire is provided between the leads 14. Second pitch is 1.0-1.
A triple coil 15 coated with an electron-emitting material is locked onto a surface having a diameter of 5 mm and a cold resistance of 5.0 to 8.0 Ω, and is electrically connected. Here, the triple coil 15
Is a wire diameter such that the cold resistance is 5.0 to 8.0 Ω, and specifically, for example, is 0.04 to 0.09 mm. Reference numeral 16 denotes a base member, and 17 denotes a base pin.

(Experimental Example 1) The structure shown in FIG.
At 0 Pa, three types of fluorescent lamps of the present invention were manufactured by changing the cold resistance and the second pitch of the triple coil.
The flicker occurrence rate when lit for 00 hours was measured.

FIG. 5 shows the results. As shown in FIG. 5, even when the second pitch is 1.1 mm, flicker occurs at about 18% when the cold resistance is 4.0 Ω. However, when the cold resistance is 5.0 Ω, the flicker occurs when the second pitch is 1.1 mm. %, 1.
It can be seen that the value is improved to about 8% at 0 mm. That is, in a fluorescent lamp using a triple coil having a cold resistance of 5.0 Ω or more and a second pitch of the main wire of 1.1 mm or more, almost no flicker occurs even at a gas pressure of 250 Pa.

The structure shown in FIG. 4 has a cold resistance of 5.0 to 8.0.
Ω, a fluorescent lamp with a triple coil having a second pitch of 1.0 to 1.5 mm was manufactured, and the mass of the electron-emitting substance held in a basket volume, which is the volume of the inner space of the triple coil, was variously changed. A fluorescent lamp of a conventional double coil electrode (pitch interval: 1.0 mm) and a relative life were measured.

FIG. 6 shows the gas pressure and relative life of these fluorescent lamps when 100% Ar gas is sealed in the glass bulb (320P of a conventional double coil fluorescent lamp).
a is set to 100%, and the life is defined as the time when the lamp stops lighting).

As shown in the figure, in a conventional fluorescent lamp using a double coil, the relative life is 320 Pa, which is 100 Pa.
% To 60% of 210 Pa, the life decreases almost linearly, whereas in the fluorescent lamp using the triple coil of the present invention, the mass of the electron-emitting substance held in the basket volume at 210 Pa is 2. Although the dose of 2 mg is slightly insufficient at about 90%, the mass of the electron-emitting substance held in the basket volume is about 1% at 3.8 mg.
00% or more. On the other hand, when the mass of the electron-emitting substance held in the basket volume is larger than 7.0 mg, the main wire becomes long, so that the cold resistance becomes too high or the temperature of the electron-emitting substance does not rise sufficiently when the lamp is turned on. In addition, problems such as blackening of the tube end occur early.

(Second Embodiment) Hereinafter, a second embodiment of the present invention will be described.
The fluorescent lamp according to the embodiment will be described.

In the following description, among the embodiments after this embodiment, the description of the same contents as those of the preceding embodiment will be omitted.

In the second embodiment, the lamp current is 50
0-700mA annular 30W fluorescent lamp (FCL3
0: manufactured by Toshiba Lighting & Technology Corp.).

The fluorescent lamp according to the present embodiment employs substantially the same configuration as the fluorescent lamp according to the first embodiment. However, the glass bulb 10 of the present embodiment is formed in an annular shape, and the cold resistance of the triple coil 15 is 1.8.
Ω5.0Ω. The wire diameter of the triple coil 15 is such that the cold resistance is 1.8 to 5.0 Ω, and specifically, for example, is 0.07 to 0.09 mm.

(Example 2) Three types of fluorescent lamps of the present invention were manufactured with the structure of the fluorescent lamp according to the second embodiment, the gas pressure was set to 250 Pa, and the cold resistance and the second pitch of the triple coil were changed. And the flicker occurrence rate at the time of lighting for 1000 hours was measured.

FIG. 7 shows the results. As shown in FIG. 7, when the cold resistance is 1.5Ω, flickering occurs at about 18% even when the second pitch is 1.2 mm. However, when the cold resistance is 2.0Ω, the flicker is 0% when the second pitch is 1.2 mm. %, 1.
It can be seen that at 1 mm, it is improved to about 8%. That is, in a fluorescent lamp using a triple coil having a cold resistance of 2.0Ω or more and a second pitch of the main wire of 1.2 mm or more, almost no flicker occurs even at a gas pressure of 250 Pa.

A fluorescent lamp having the same structure as the fluorescent lamp according to the second embodiment and having a triple coil having a cold resistance of 1.8 to 5.0Ω and a second pitch of 1.0 to 1.5 mm was manufactured. By varying the mass of the electron-emitting substance held in the basket volume, which is the volume of the inner space of the triple coil, the relative life of the fluorescent lamp of the conventional double coil electrode (pitch interval: 1.0 mm) was measured.

FIG. 8 shows the gas pressure and the relative life of these fluorescent lamps when Ar gas is filled in a glass bulb at 100% (320P of a conventional double coil fluorescent lamp).
a is set to 100%, and the life is defined as the time when the lamp stops lighting).

As shown in the figure, a conventional fluorescent lamp using a double coil has a relative life of 320 Pa, which is 100 Pa.
% To 60% of 210 Pa, the life decreases almost linearly, whereas in the fluorescent lamp using the triple coil of the present invention, the mass of the electron-emitting substance held in the basket volume at 210 Pa is 2. 8 mg is about 90%, which is slightly insufficient, but the mass of the electron-emitting substance held in the basket volume is about 1% at 4.5 mg.
00% or more. In addition, when the mass of the electron-emitting substance held in the basket volume is larger than 8.0 mg, the main wire becomes longer, so that the cold resistance becomes too high, or the temperature of the electron-emitting substance becomes sufficiently high when the lamp is turned on. It does not rise, causing problems such as blackening of the pipe end portion at an early stage.

(Third Embodiment) Hereinafter, a third embodiment of the present invention will be described.
The fluorescent lamp according to the embodiment will be described.

In the third embodiment, after manufacturing a triple coil in which the second pitch of the main wire is less than 1.0 mm, the triple pitch is extended to reduce the second pitch of the main wire to 1.0 to 1.5 mm. Configuration.

FIG. 9 is a diagram schematically showing triple coils and leads of a fluorescent lamp according to the third embodiment.

First, after manufacturing a triple coil 20 in which the second pitch of the main wire is less than 1.0 mm,
The triple coil 20 is locked between the leads 21 as shown in FIG. Here, in this state, it is assumed that it is not housed in the glass bulb 10 and that the electron-emitting substance is not held in the triple coil 20.

After the triple coil 20 is locked between the leads 21, the distance between the leads 21 is increased by an unillustrated device for increasing the distance between the leads 21.
The triple coil 20 is extended so that the second pitch of the main wire is in the range of 1.0 to 1.5 mm as shown in FIG.

After that, the triple coil 20 is accommodated in the glass bulb 10 by holding the carbonate of the substance acting as the electron-emitting substance in the triple coil 20. Here, the reason why the carbonate of the substance acting as the electron-emitting substance is retained after the triple coil 20 is extended is to prevent the carbonate from dropping out when the triple coil 20 is extended.

As described above, in the fluorescent lamp according to the present embodiment, the triple pitch of the main wire is manufactured after the triple coil 20 having the second pitch of less than 1.0 mm is manufactured, and then the triple pitch of the triple coil 20 is extended. By adopting a configuration of 0.0 to 1.5 mm, the same effects as those of the first and second embodiments can be obtained, and at the time of manufacturing the triple coil 20 and the fluorescent lamp, the main component forming the triple coil 20 can be obtained. The entanglement between the wire and the sub-wire can be prevented, and the triple coil 20 and the fluorescent lamp can be easily manufactured.

An experiment similar to those of the first and second embodiments was performed using the fluorescent lamp having the triple coil 20. As a result, the same results as those of the first and second embodiments were obtained. Was.

It should be noted that the present invention is not limited to the contents described in the first and second embodiments, and the structure, material, arrangement of each member and the like may be appropriately changed without departing from the gist of the present invention. Can be changed. For example, in the third embodiment,
After manufacturing the triple coil 20 in which the second pitch of the main wire is less than 1.0 mm, the triple pitch of the triple coil 20 is extended to make the second pitch of the main wire 1.0 to 1.5 mm. After manufacturing a triple coil in which the second pitch of the main wire of the coil is more than 1.5 mm, the triple coil is narrowed by a lead distance reducing device (not shown) for reducing the distance between the leads to reduce the second pitch of the main wire to 1.0.
It is also possible to make it 1.5 mm.

[0066]

According to the fluorescent lamp of the present invention, since a triple coil having a strong holding power for the electron-emitting substance is used and the flicker caused by the anode vibration is improved, the illuminance can be improved without impairing the life characteristics. it can.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a manufacturing state of a triple coil used for a fluorescent lamp of the present invention.

FIG. 2 is a view schematically showing a manufacturing state of a triple coil used for the fluorescent lamp of the present invention.

FIG. 3 is a view schematically showing a manufacturing state of a triple coil used for the fluorescent lamp of the present invention.

FIG. 4 is a partial sectional view schematically showing the fluorescent lamp according to the first embodiment.

FIG. 5 is a graph showing a flicker occurrence rate of the fluorescent lamp of the straight tube 20W according to the first embodiment.

FIG. 6 is a graph showing a relative life of the fluorescent lamp of the straight tube 20W according to the first embodiment.

FIG. 7 is a graph showing a flicker occurrence rate of an annular type 30 W fluorescent lamp according to Example 2.

FIG. 8 is a graph showing the relative life of the annular 30 W fluorescent lamp according to the second embodiment.

FIG. 9 is a diagram schematically showing a triple coil and leads of a fluorescent lamp according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st mandrel wire 2 ... main wire 3 ... sub wire 4 ... 2nd mandrel wire 5 ... 3rd mandrel wire 6 ... triple coil 10 ... glass bulb 11 ... phosphor film 13 ...... Stem 14,21 ...... Lead 15,20 ...... Triple coil 16 ...... Base member 17 ... Base pin

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shoji Naoki 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo F-term in Toshiba Lighting & Technology Corporation (reference) 5C015 AA01 CC02 CC03 CC04 EE02 EE08 PP02 PP03 PP04 PP07 PP08

Claims (6)

[Claims] A glass bulb having an inner surface coated with a phosphor; and a molar ratio of Ne: Ar: Kr in said glass bulb.
= A: b: c (a + b + c = 1), total pressure P (Pa)
Is P (0.4a + b + 1.8c) = 210-280 (P
a rare gas sealed so as to satisfy the relationship a); mercury sealed in the glass bulb; a pair of stems sealing both ends of the glass bulb; A pair of leads through which a lamp current of ~ 700 mA flows; electrically connected between the pair of leads, respectively;
A triple coil having a cold resistance of 1.8 to 8.0 Ω; an electron-emitting substance held by the triple coil; and a base member attached to an end of the glass bulb. A fluorescent lamp. 2. The method according to claim 1, wherein the lamp current is 300 to 450 mA,
The fluorescent lamp according to claim 1, wherein the cold resistance is 5.0 to 8.0 Ω. 3. The lamp current is 500 to 700 mA,
The fluorescent lamp according to claim 1, wherein the cold resistance is 1.8 to 5.0Ω. 4. The mass of the electron-emitting substance is 3.8 to 3.8.
3. The fluorescent lamp according to claim 2, wherein the amount is 7.0 mg. 5. The mass of the electron-emitting substance is 4.5 to 4.5.
The fluorescent lamp according to claim 3, wherein the amount is 8.0 mg. 6. The device according to claim 1, wherein the triple coil is extended and connected to the pair of leads.
6. The fluorescent lamp according to any one of items 5 to 5.