JP2000331643A - Fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly efficient and long life fluorescent lamp provided with an electrode having a metal sleeve and an emitter by using an emitter rarely exfoliated or falling off from the metal sleeve, and not absorbing a rare gas. SOLUTION: This device is provided with a glass sleeve 11 and a pair of electrodes 12 inside the glass sleeve 11. The electrodes 12 are provided with a metal sleeve 12a and an emitter 12b provided at least on a part of the metal sleeve 12a. The emitter 12b includes at least one of materials selected from BaO1-X (0<=X<=1), SrO1-X (0<=X<=1), CaO1-X (0<=X<=1), and MgO1-X (0<=X<=1), and glass.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluorescent lamp,
In particular, for example, it relates to a cold cathode fluorescent lamp.

[0002]

2. Description of the Related Art Generally, in a hot cathode fluorescent lamp,
In order to efficiently emit electrons from the electrode, a mixed oxide emitter electrode obtained by applying a mixed carbonate of barium, strontium, calcium, etc. to a tungsten filament as an emitter material and energizing and decomposing these with a tungsten filament has been widely used. I have. On the other hand, in the cold cathode fluorescent lamp, in the electrode structure having the mixed oxide emitter on the tungsten filament, the emitter is scattered during lighting by ion bombardment due to the operation of the cold cathode, so that a long life cannot be secured. For this reason, in a cold cathode fluorescent lamp, a hollow electrode structure in which the emitter is provided on the inner surface of a metal sleeve to suppress the scattering of the emitter is widely known (Japanese Patent Application Laid-Open No. 64-3384). In addition, when a lamp having such an electrode structure is used at a high power, the scattering of the electrode material due to ion bombardment is large, and a blackening phenomenon appears on the inner wall of the lamp at an early stage. From Japanese Patent Laid-Open No. 4-3 / 1993, there is known an electrode having a structure in which a mixture of an emitter powder and a metal powder is baked in a state close to alloying with a metal sleeve.
No. 37239).

[0003]

However, in the above-mentioned conventional cold cathode fluorescent lamp using a hollow electrode, when performing thermal decomposition and activation of a carbonate to an oxide,
There has been a problem that the emitter is peeled off from the metal sleeve due to thermal contraction of the emitter or the like. For this reason, in the conventional cold cathode fluorescent lamp, the emitter on the inner surface of the hollow electrode becomes insufficient due to the peeling or falling off of the emitter, and the emitter effect disappears in several thousand hours of operation. Further, when the dropped emitter has a size of 0.5 mm ² or more, there is a problem that the brightness distribution of the fluorescent lamp becomes non-uniform due to the shadow and the shadow is generated on the liquid crystal panel.

In a conventional cold cathode fluorescent lamp using an electrode in which a mixture of an emitter powder and a metal powder is baked,
Although the problems such as peeling and falling off of the emitter can be improved, there is a problem that, depending on the composition of the mixture, the rare gas in the lamp is absorbed by the electrode constituent materials during lamp operation, and the lamp does not operate.

[0005] In order to solve the above-mentioned problems, the fluorescent lamp of the present invention is to provide a high-efficiency and long-life fluorescent lamp by using an emitter which does not peel off or fall off from the metal sleeve and does not absorb rare gas. Aim.

[0006]

To achieve the above object, a fluorescent lamp according to the present invention is a fluorescent lamp including a glass bulb and a pair of electrodes disposed inside the glass bulb, wherein the electrode is , A metal sleeve and an emitter provided on at least a part of the metal sleeve, wherein the emitter is BaO _1-A (where 0 ≦ A ≦
1), SrO _1-B (where 0 ≦ B ≦ 1), CaO
_1-C (however, 0 ≦ C ≦ 1) and MgO _1-D (however,
0 ≦ D ≦ 1) and glass. In the fluorescent lamp of the present invention,
The adhesion strength of the emitter to the metal sleeve can be improved, and the emitter can be prevented from peeling and falling off from the metal sleeve. Therefore, according to the fluorescent lamp of the present invention, a long-lasting, high-efficiency fluorescent lamp having a long-lasting emitter effect can be obtained. In the fluorescent lamp of the present invention,
Since the emitter does not absorb the rare gas, a fluorescent lamp having a particularly long life and high efficiency can be obtained.

In the above-described fluorescent lamp of the present invention, it is preferable that the amount of the glass in the emitter is not less than 5 wt% and not more than 40 wt% with respect to the emitter. By setting the amount of glass in the emitter to 5 wt% or more with respect to the emitter, it is possible to sufficiently secure the adhesion strength of the emitter to the metal sleeve. By setting the amount of glass in the emitter to 40 wt% or less with respect to the emitter, the emitter effect can be maintained for a long time without impairing the effect.
High efficiency can be sustained.

In the above-described fluorescent lamp of the present invention, the emitter is also provided on the outer peripheral surface of the metal sleeve, and the area of the emitter provided on the outer peripheral surface is 1.0 mm ² or more. Is preferred. According to the above configuration, the photoelectric effect of the emitter provided on the outer peripheral surface of the metal sleeve is large, so that only a small amount of light is applied to the lamp, enough initial electrons are emitted from the electrode to start the discharge, A fluorescent lamp having good starting characteristics in a dark place can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) In Embodiment 1,
An example of the fluorescent lamp of the present invention will be described.

FIG. 1 is a partially enlarged sectional view of a fluorescent lamp 10 according to the first embodiment. FIG. 1 shows one end of the fluorescent lamp 10, and the other end is the same as the one shown in FIG.

Referring to FIG. 1, a fluorescent lamp 10 includes a glass bulb 11 and a pair of electrodes 12 arranged inside the glass bulb 11.

The glass bulb 11 is made of borosilicate glass or the like, and a phosphor 13 is applied on the inner surface thereof. The phosphor 13 is made of, for example, (Y, Eu) ₂ O ₃ , (L
a, Ce, Tb) PO ₄ , (Ba, Eu) MgAl ₁₀ O
_It consists of ₁₇ three-wavelength phosphors. Both ends of the glass bulb 11 are sealed by glass beads 14. Mercury and a rare gas (not shown) are sealed inside the glass bulb 11 sealed by the glass beads 14.

The electrode 12 has a metal sleeve 12a and an emitter 12b provided on at least a part of the metal sleeve 12a. FIG. 1 shows the metal sleeve 12.
3A shows an example in which the emitter 12b is formed on the inner surface of the metal sleeve 12a.
Is formed, there is no limitation on the formation position of the emitter 12b. However, by providing the emitter 12b on at least the inner surface of the metal sleeve 12a, scattering and wear of the emitter 12b can be prevented, and the emitter effect can be maintained for a long time.

The metal sleeve 12a is made of a metal having heat resistance higher than the activation temperature of the emitter (for example, 1100 ° C.). As a material of the metal sleeve 12a, for example, nickel, stainless steel, cobalt, iron, or the like can be used. One end of the metal sleeve 12a is welded to an internal lead 15 made of tungsten or the like, and the internal lead 15 is connected to an external lead 16 through a glass bead 14.

The emitter 12b is made of BaO _1-A (however,
0 ≦ A ≦ 1), SrO _1-B (where 0 ≦ B ≦ 1), C
It contains at least one selected from aO _1-C (where 0 ≦ C ≦ 1) and MgO _1-D (where 0 ≦ D ≦ 1) and glass.

As the glass contained in the emitter 12b, glass that melts at or below the activation temperature of the emitter (eg, 1100 ° C.) can be used. For this, for example, glass made of a molten material such as CaO, BaO, B ₂ O ₃ and P ₂ O _3, low melting point glass such as soda glass and borosilicate glass can be used.

The emitter 12b preferably contains the above glass at a content of 5% by weight or more and 40% or less.

The emitter 12b is made of BaCO ₃ , SrC
Mixing an emitter powder consisting of at least one selected from O ₃ , CaCO ₃ and MgCO ₃ with a glass powder,
It can be formed by heat treatment. The glass powder mixed with the emitter powder may be any glass powder that melts at a temperature lower than the activation decomposition temperature and the activation temperature of the emitter. For example, low melting glass powder, which is a melt of CaO, BaO, and B ₂ O ₃ , soda glass powder, borosilicate glass powder, and the like can be used.

In the fluorescent lamp 10 of the first embodiment, the emitter provided on a part of the metal sleeve is made of BaO _{1 -A}
(However, 0 ≦ A ≦ 1), SrO _1-B (However, 0 ≦ B
≦ 1), CaO _1-C (where 0 ≦ C ≦ 1) and Mg
It contains at least one selected from O _1-D (where 0 ≦ D ≦ 1) and glass. Therefore, according to the fluorescent lamp 10, the emitter is less likely to peel or fall off from the metal sleeve, and there is no rare gas absorption by the emitter, so that a fluorescent lamp with high efficiency and long life can be obtained.

Embodiment 2 In Embodiment 2, another example of the fluorescent lamp of the present invention will be described.

The fluorescent lamp 10 according to the second embodiment differs from the fluorescent lamp 10 described in the first embodiment only in the shape of the emitter 12b, and a duplicate description will be omitted.

FIG. 2 is a partially enlarged sectional view of the fluorescent lamp 10. As shown in FIG. As shown in FIG.
Includes a metal sleeve 12a and an emitter 12b. The emitter 12b is formed not only on the inner surface of the metal sleeve 12a but also on a part of the outer peripheral surface of the metal sleeve 12a.

In the fluorescent lamp 10 of the second embodiment, the area of the emitter 12b formed on the outer peripheral surface of the metal sleeve 12a is preferably 1.0 mm ² or more.

The composition and the like of the emitter 12b are the same as those in the first embodiment, and a duplicate description will be omitted.

According to the fluorescent lamp 10 of the second embodiment, similarly to the fluorescent lamp 10 of the first embodiment, a high-efficiency and long-life fluorescent lamp can be obtained.

Further, in the fluorescent lamp 10 of the second embodiment, since the emitter 12b is also provided on the outer peripheral surface of the metal sleeve 12a, a fluorescent lamp having good starting characteristics can be obtained.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of the fluorescent lamp of the present invention will be described.
This will be described in detail with reference to examples.

Example 1 In Example 1, an example of the fluorescent lamp 10 described in Embodiment 1 will be described.

Referring to FIG. 1, the fluorescent lamp of Example 1 has an outer diameter of 1.0 mm and an inner diameter of 0.8 m made of nickel or the like.
m, an inner lead wire 15 made of tungsten or the like and having an outer diameter of 0.6 mm at one end of a metal sleeve 12a having a length of 3.0 mm.
Is inserted, and one end of the metal sleeve 12a is crush-welded to connect the two.

The glass bulb 11 is made of borosilicate glass or the like having an outer diameter of 2.1 mm and an inner diameter of 1.5 mm. Electrodes 12 are arranged at both ends of the glass bulb 11. Electrode 12
Represents BaO _1-A (where 0 ≦ A ≦ 1) and SrO _1-B
(Where 0 ≦ B ≦ 1) and an emitter 12 containing glass
b.

Both ends of the glass bulb 11 are sealed with a glass bead 14 made of borosilicate glass or the like, and the internal lead 15 is connected to the external lead 16 through the glass bead 14. . The distance between the tips of the pair of electrodes 12 was 80 mm. In addition, glass bulb 1
A phosphor 13 was applied to the inner surface of Sample No. 1 and a mixed gas of argon and neon was sealed therein together with mercury so that the pressure became 11 kPa.

The fluorescent lamp of Example 1 was formed by the following method.

First, the emitter 12b was formed on the inner surface of the metal sleeve 12a by the following method. First, BaCO
₃ powder and SrCO ₃ powder in a molar ratio of BaCO ₃ : Sr
An emitter powder mixed so that CO ₃ = 2: 1 was prepared. Thereafter, a mixed carbonate suspension was prepared by dispersing 10 kg of the emitter powder in 20 liters of a mixture of butyl acetate and nitrocellulose. Next, a low-melting glass powder or the like, which is a molten material of CaO, BaO, B ₂ O ₃ , and P ₂ O ₃ , is prepared, and 20 wt% of the low-melting glass powder based on the weight of the emitter powder is mixed with the mixed carbonate suspension. To adjust the carbonate suspension. Next, 1.0 mm of the tip of the opening of the metal sleeve 12a was immersed in an emitter solution (the above-mentioned carbonate suspension) having a specific gravity of 1.2. At this time, since there is an inner and outer diameter difference of 0.2 mm between the metal sleeve 12a and the inner lead wire 15, a gap of about 0.1 mm is formed in the welded portion, and the emitter liquid is applied to the inner surface of the metal sleeve 12a by a capillary phenomenon. Infiltrated. After allowing this to air dry in the air, the emitter layer on the outer peripheral surface of the metal sleeve 12a was wiped off with a cloth to form a metal sleeve 12a coated with the emitter liquid only on the inner surface of the metal sleeve 12a.

Thereafter, the metal sleeve 12a coated with the emitter solution is heated to about 1100 ° C. in a reducing furnace in an argon atmosphere to simultaneously perform thermal decomposition and activation of the emitter and melting of the low-melting glass powder. 1
The electrode 12 including 2b was formed. During this heat treatment, the low melting point glass powder melts, and B
aO _1-A (however, 0 ≦ A ≦ 1) and SrO _1-B (however,
0 ≦ B ≦ 1) and the glass powder were mixed to form an emitter 12b having a high adhesion strength.

Thereafter, the emitter-activated electrode 12
As shown in FIG. 3, the glass bulb 11 coated with the phosphor 13 is disposed at the end and the center, and only the electrode 12 at the end is first sealed with a burner via a glass bead 14 in an argon atmosphere. I wore it. The other electrode 12 is the glass bulb 1
Only a part of the glass bead 14 is melted so that a gap is formed between the glass bulb 11 and the glass bead 14.
Was temporarily fixed at the center.

Thereafter, the mercury compound 17 for filling mercury is
It was inserted into the area of the glass bulb 11 where the phosphor 13 was not applied (clear section 18).

Thereafter, the glass bulb 11 was fixed in a bell jar. After the inside of the bell jar was evacuated to a high vacuum of 1 × 10 ⁻⁷ Pa while being heated to 600 ° C., a mixed gas of argon and neon was introduced into the bell jar so as to have a pressure of 11 kPa. The open end was sealed.

Thereafter, mercury is released from the mercury compound 17 by high-frequency induction heating, and the mercury is moved from the gap between the glass bulb 11 and the glass bead 14 into the phosphor coating region. The book was sealed in position.

The fluorescent lamp of the present invention formed by the above method is lit using a high-frequency lighting circuit under conditions of an ambient temperature of 25 ° C. and no wind (lamp current 4 mA, lighting frequency 60).
kHz), and the change over time in the lamp voltage was examined. The result of the measurement is shown by the line A in FIG. In addition, as comparative examples, the results were similarly measured for a fluorescent lamp B having an emitter without glass powder mixed therein and having the emitter dropped off, and a fluorescent lamp C using an electrode consisting of only a metal sleeve having no emitter. Is shown in FIG.

As is apparent from FIG. 4, the lamp voltage at the initial stage of continuous lighting of the fluorescent lamp (line A) of the present invention is about 2
The lamp voltage was 40 Vrms (effective value), and a lamp voltage of about 240 Vrms could be maintained until the continuous lighting time exceeded 10,000 hours. On the other hand, in the case of the fluorescent lamp C (line C) using the electrode composed of only the metal sleeve having no emitter, the lamp voltage at the beginning of the continuous lighting was about 290 Vrms.
This indicates that the use of the emitter can reduce the lamp voltage in the initial stage of continuous lighting by 50 Vrms.

In the case of a fluorescent lamp B (line B) having an emitter not mixed with glass and having the emitter dropped, the lamp voltage at the initial stage of continuous lighting is 240 Vrms.
Which was equivalent to that of the fluorescent lamp of the present invention. However, in the case of the fluorescent lamp B, in which the emitter has peeled off and fell off, the amount of the emitter does not exist in the electrode as compared with the fluorescent lamp of the present invention, so that the lamp voltage gradually increases after the continuous lighting time of 1000 hours has elapsed. After 3000 hours, the lamp voltage was equivalent to that of the fluorescent lamp C using no emitter. For comparison, a fluorescent lamp in which the emitter was formed only on the outer peripheral surface of the metal sleeve was prepared. In this fluorescent lamp, the lamp voltage became 290 Vrms in 100 hours of continuous lighting, and the emitter effect was 100%.
It was found to disappear in less than an hour.

The fluorescent lamp of the present invention and the fluorescent lamp B of the comparative example each have a frequency of 1
Vibration of 2mm amplitude at 0Hz ~ 20Hz, frequency 22H
vibration at an acceleration of 14.7 m / s ² at z to 500 Hz;
A vibration test was conducted in each of X, Y, and Z directions for 30 minutes. As a result, the dropout rate of the emitter was 0% in the fluorescent lamp of the present invention, whereas it was 24% in the fluorescent lamp B using the emitter containing no glass.

As described above, the fluorescent lamp of the first embodiment is
BaO _1-A (where 0 ≦ A ≦ 1) and SrO _1-B (0
≦ B ≦ 1) and an electrode provided with an emitter that is heated and melted by mixing an emitter powder comprising glass powder and an emitter powder. Therefore, in the fluorescent lamp of Example 1, since the adhesion strength of the emitter to the metal sleeve was high, the peeling or falling off of the emitter was small, and the high emitter effect was maintained for a long time. Furthermore, in the fluorescent lamp of the first embodiment, since the emitter is provided on the inner surface of the metal sleeve, the emitter scattered during lighting is captured and reused on the inner surface of the metal sleeve. Lasted. Also, by suppressing the peeling or falling off of the emitter from the metal sleeve, the brightness distribution of the fluorescent lamp can be maintained uniform,
This solves the problem of shadows on the LCD screen. In addition, no rare gas adsorption by the emitter material occurred.

Example 2 In Example 2, an example of the fluorescent lamp 10 described in Embodiment 2 will be described.

Referring to FIG. 2, in the fluorescent lamp of the second embodiment, emitter 12b is connected to the inner surface of metal sleeve 12a.
It was formed in a range of 1.0 mm from the opening on the outer peripheral surface. At this time, the area of the emitter 12b formed on the outer peripheral surface of the metal sleeve 12a was set to 1.0 mm ² or more. Example 2
The fluorescent lamp has the same structure as that of the first embodiment except that the emitter 12b is also provided on the outer peripheral surface of the metal sleeve 12a. Further, the fluorescent lamp of Example 2 was manufactured by the same method as the fluorescent lamp of Example 1.

Regarding the fluorescent lamps of Examples 1 and 2,
The starting probability was examined in a dark place with an ambient illuminance of 0.1 lux or less. Table 1 shows the results.

[0047]

[Table 1]

As shown in Table 1, when the output voltage of the lighting circuit was 1000 Vrms and the output time was 2000 msec, both of the fluorescent lamps of Examples 1 and 2 had a starting probability of 100% in a dark place. . However, the output voltage of the lighting circuit is 1000 Vrms, and the output time is 500 m.
In the case of sec, the starting probability of the fluorescent lamp of Example 2 was 100%, whereas the starting probability of the fluorescent lamp of Example 1 was 90%. Further, when the output of the lighting circuit is 700 Vrms and the output time is 500 msec, the starting probability of the fluorescent lamp of the second embodiment is 100%, whereas the starting probability of the fluorescent lamp of the first embodiment is 7%.
It was 0%.

On the other hand, in the same fluorescent lamp as in the second embodiment, when the area of the emitter formed on the outer peripheral surface of the metal sleeve is less than 1.0 mm ² , the output voltage of the lighting circuit is reduced to 7 mm.
When the output time was set to 500 msec and the output time was set to 00 Vrms, it was found that the starting probability of the fluorescent lamp did not become 100%.

From the above, it was found that in the fluorescent lamp of Example 2, the startability in a dark place can be improved by forming the emitter on the outer peripheral surface of the metal sleeve. Further, it was found that by setting the area of the emitter formed on the outer peripheral surface of the metal sleeve to 1.0 mm ² or more, the startability in a dark place can be further improved.

Example 3 In Example 3, another example of the manufacture of the fluorescent lamp of Embodiment 2 will be described. In the third embodiment, the fluorescent lamp described in the second embodiment was manufactured by changing the amount of glass in the emitter in the range of 5 wt% to 40 wt% with respect to the emitter. With respect to the fluorescent lamp thus prepared, a vibration having a frequency of 10 Hz to 20 Hz and an amplitude of 2 mm and a vibration having a frequency of 22 Hz to 500 Hz and an acceleration of 14.7 m / s ² are applied in the X, Y, and Z directions for 30 minutes each. A vibration test was performed. As a result, it was found that when the amount of glass in the emitter was 5 wt% or more with respect to the emitter, the dropout rate of the emitter was 0%. When the amount of glass in the emitter is 4 wt% with respect to the emitter, the falling rate is 5%, and the falling rate may increase in proportion to the decrease in the amount of glass in the emitter. Do you get it.

The fluorescent lamp was lit continuously using a high-frequency lighting circuit (lamp current: 4 mA, lighting frequency: 60 kHz), and the lamp voltage was measured at a cumulative lighting time of 10,000 hours. FIG. 5 shows the measurement results.

As shown in FIG. 5, when the amount of glass in the emitter was in the range of 30 wt% or less with respect to the emitter, the lamp did not rise during the cumulative lighting time of 10,000 hours.
However, when the amount of glass in the emitter is 40 wt% with respect to the emitter, the lamp voltage increases by 5 Vrms (decreases in efficiency by about 10%), and when the amount of glass in the emitter exceeds 40 wt% with respect to the emitter. It was found that the lamp voltage suddenly increased.

As described above, when the amount of glass in the emitter is set in the range of 5 wt% to 40 wt% of the weight of the emitter in the fluorescent lamp described in the second embodiment, the emitter is dropped from the metal sleeve. Can be suppressed, and an increase in lamp voltage during continuous lighting can be suppressed.

[0055]

As described above, in the fluorescent lamp of the present invention, the emitter is made of BaO _1-A (where 0 ≦ A ≦
1), SrO _1-B (where 0 ≦ B ≦ 1), CaO
_1-C (however, 0 ≦ C ≦ 1) and MgO _1-D (however,
0 ≦ D ≦ 1) and glass. Therefore, according to the fluorescent lamp of the present invention, since there is little peeling or falling off of the emitter from the metal sleeve, and there is no absorption of the rare gas by the emitter, a fluorescent lamp with high efficiency and long life can be obtained. Further, according to the fluorescent lamp of the present invention, a fluorescent lamp having good starting characteristics in a dark place can be obtained.

Further, in the fluorescent lamp of the present invention, by setting the amount of glass in the emitter to 5 wt% or more with respect to the emitter, the adhesion strength of the emitter to the metal sleeve can be sufficiently ensured. In the fluorescent lamp of the present invention, the amount of glass in the emitter is set to 40 w
By setting the content to t% or less, high efficiency can be maintained for a long time without damaging the emitter effect.

In the fluorescent lamp of the present invention, the emitter is also provided on the outer peripheral surface of the metal sleeve, and the area of the emitter provided on the outer peripheral surface of the metal sleeve is set to 1.0 mm ² or more, so that the fluorescent lamp can be used in a dark place. A fluorescent lamp having particularly good starting characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view showing an example of a fluorescent lamp of the present invention.

FIG. 2 is a partially enlarged sectional view showing another example of the fluorescent lamp of the present invention.

FIG. 3 is a sectional view showing a manufacturing process of the fluorescent lamp of the present invention.

FIG. 4 is a diagram showing the relationship between the cumulative lighting time and the lamp voltage for the fluorescent lamp of the present invention.

FIG. 5 is a diagram showing the relationship between the amount of glass in the emitter and the lamp voltage for the fluorescent lamp of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fluorescent lamp 11 Glass bulb 12 Electrode 12a Metal sleeve 12b Emitter 13 Phosphor 14 Glass bead 15 Internal lead 16 External lead

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshihiro Terada 1-1, Komachi, Takatsuki-shi, Osaka Matsushita Electronics Co., Ltd. F-term (reference) 5C015 AA03 AA04 BB04 BB07 CC02 CC03 CC04

Claims (3)

[Claims] 1. A fluorescent lamp comprising a glass bulb and a pair of electrodes disposed inside the glass bulb, wherein the electrode comprises a metal sleeve and an emitter provided on at least a part of the metal sleeve. The emitter is BaO _1-A (where 0 ≦ A ≦ 1);
SrO _1-B (where 0 ≦ B ≦ 1), CaO _1-C (where 0 ≦ C ≦ 1) and MgO _1-D (where 0 ≦ D ≦
A fluorescent lamp comprising at least one selected from 1) and glass. 2. The fluorescent lamp according to claim 1, wherein an amount of the glass in the emitter is 5 wt% or more and 40 wt% or less with respect to the emitter. 3. The emitter is also provided on the outer peripheral surface of the metal sleeve, and the area of the emitter provided on the outer peripheral surface is 1.
The fluorescent lamp according to claim 1, wherein the size of the fluorescent lamp is 0 mm ² or more.