JPH03280351A - Fluorescent lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention is directed to a fluorescent lamp suitable for use as a display element of an electronic display panel, for example, and a fluorescent lamp suitable for a light emitting element of Airoba decorative lighting. In particular, the present invention relates to a fluorescent lamp that achieves both lower starting voltage and higher brightness.

(Prior Art) In general, display fluorescent lamps suitable for display elements such as electronic display panels include single-tube monochromatic or single-tube multicolor fluorescent lamps.

An example of such a lamp is a fluorescent lamp 1 constructed as shown in FIGS. 6 and 7, in which a cylindrical or similar envelope 2 is filled with a discharge gas such as mercury and a rare gas. , a cathode 3 that is a common electrode, and a plurality of electrodes, for example, four anodes 4a.

4b, 4c, and 4d are arranged facing each other and housed in an airtight manner.

Further, in the discharge space between the cathode 3 and each of the other anodes 4a to 4d, the fluorescent lamp 1 houses a discharge path regulating body 5 having, for example, a funnel-shaped longitudinal section in the envelope 2,
A part of this discharge space is formed into a plurality of parallel discharge paths corresponding to the number of electrodes of the anodes 48 to 4d.

Further, the discharge path regulating body 5 has red (R), G (green), and B (blue) on the surface facing each parallel discharge path, for example, for each parallel discharge path.
Four light emitting chambers 5a, 5b, 5c are each coated with a required fluorescent film so as to emit colored light.

5d, and circular discharge holes 6a, 6b, 6c, and 6d with the same diameter are formed in each of the light emitting chambers 5a to 5d to allow discharge to pass through.

Therefore, by selectively energizing the cathode 3 and the anodes 48 to 4d, each of the light emitting chambers 5a to 5d can emit colored light as appropriate, and the light can be emitted from the transparent plate 7 to the outside.

(Problem to be Solved by the Invention) By the way, as shown in FIG. 8, the hole diameter of each of the discharge holes 6a to 6d and the relative value of the discharge starting voltage are inversely proportional.

Therefore, by gradually and uniformly reducing the diameter of each discharge hole 6a to 6d, the impedance between the cathode 3 and each anode 48 to 4d can be increased, and more watts (W) can be input. High brightness can be achieved.

However, on the other hand, since the starting voltage increases, the withstand voltage capacity h1 of the lighting circuit for lighting the fluorescent lamp 1 increases, resulting in an increase in size and cost of the lighting circuit itself.

If, on the contrary, the diameters of the discharge holes 6a to 6d are gradually and uniformly expanded, the discharge starting voltage will decrease, but at the same time, the brightness will decrease.

Further, when the light-transmitting plate 7 is viewed from the front, each of the discharge holes 68 to 6d appears as a black dot and hardly contributes to light emission, so there is a problem in that it gives a visual sense of unevenness.

The present invention has been made in consideration of the above circumstances, and its object is to provide a fluorescent lamp that can reduce the starting voltage and increase the brightness.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above problems, the present invention is configured as follows.

That is, the present invention provides a fluorescent lamp in which a plurality of electrodes arranged opposite to a common electrode and each discharging with the common electrode are housed in a plurality of light emitting chambers, and a discharge hole through which the discharge passes is arranged in each light emitting chamber. , at least one of the plurality of discharge holes is thicker than the other discharge holes, and is configured to constantly cause a slight discharge between the common electrode and the plurality of electrodes. .

(Operation) A slight discharge is constantly generated between the common electrode and the plurality of electrodes, and this minute discharge passes through the discharge hole of each light emitting chamber.

Since at least one of these discharge holes is larger than the others, a slight discharge is generated through this large discharge hole when starting a slight discharge, so that the starting voltage of this slight discharge is reduced.

Furthermore, since a slight discharge is constantly occurring between the common electrode and the plurality of electrodes, the starting voltage for transitioning from this slight discharge to the main discharge is reduced.

Furthermore, at least one of the discharge holes can be made large and the others made small, so in this case, not only can high brightness be achieved with this small discharge hole, but also visual color unevenness can be reduced. can be reduced.

That is, according to the present invention, it is possible to reduce the starting voltage, increase the brightness, and reduce visual color unevenness.

(Example) An example of the present invention will be described below based on FIGS. 1 to 5.

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line ■ to ■ in FIG. It is formed into a bottomed cylindrical shape by, for example, punching a thin metal plate, and its axial end (upper end in the figure) is open.

The lamp casing 20 has its opening upper end gradually expanded into a rectangular tube shape in two stages, upper and lower, to form an upper step 20a and a lower step 20b, each having a rectangular planar shape, for example. A glass film (not shown) is coated on the entire inner circumferential surface from the lower end of the lamp casing 2o to the lower bottom of the lamp casing 2o.
The glass coating prevents the internal impurity gas from being released from the 0.

Further, a center hole 20c is bored in the bottom of the lamp casing 20.

Next, the configuration of this embodiment will be explained based on FIG. 3 in approximately the order of assembly.

First, a button stem 21 formed into a disk shape made of glass to fit the cylinder is inserted into the cylindrical lower part of the lamp casing 20, and is tightly fitted into the cylindrical bottom.

After this, the outer peripheral surface of the button stem 21 is aligned with the lamp casing 2.
A cathode 22, which is a common electrode, is erected on the button stem 21, and a pair of lead wires 22a support both ends of the cathode 22. , 22b are passed through the button stem 21 in the thickness direction and electrically connected to a lighting circuit (not shown).

The button stem 21 has a center hole 21a in its center, and a glass exhaust pipe 23 is integrally protruded from the lower opening periphery of the center hole 21a. The tip of the exhaust pipe 23 is airtightly fitted into the bottom of the lamp casing 20.
It extends outward from the bottom center hole 20c.

Next, the outer casing 24a of the discharge regulator 24 is inserted into the lamp casing 20.

The discharge path regulator 24 is located inside the funnel-shaped outer casing 24a.
A cross-shaped partition plate 24b is fitted coaxially, for example, 4
It is partitioned into four light emitting chambers 25a, 25b, 25c, and 25d.

Outer casing 24a facing these light emitting chambers 25a to 25d
For example, on each inner surface of the partition plate 24b and each outer surface of the partition plate 24b, there is a fluorescent film that sequentially emits green (G), red (R), green (G), and blue (B) for each of the light emitting chambers 25a to 25d. 26 are respectively deposited.

After inserting the discharge path regulator 24 into the lamp casing 20, a plurality of electrodes, for example four anodes 27, are inserted into the lamp casing 20.
a, 27b, 27c, and 27d are inserted into the lamp casing 20.

Each of the anodes 27a to 27d has a straight short axis with a slightly larger diameter at its tip, and each of the light emitting chambers 25a to 27d has a substantially rectangular shape.
25d at the top of each corner.

Next, a rectangular flat transparent glass transparent plate 28 is fitted into the upper step 2Oa of the lamp casing 20, and the inner surface of the transparent plate 28 is connected to the outer casing 24a of the discharge path regulating body 24 and the partition plate 24b. The transparent plate 28 is brought into contact with the upper end and fixed to the upper step part 20a by means of a frit glass, and this light-transmitting plate 28 is used as a display surface of the fluorescent lamp.

The outer casing 24a has, for example, circular discharge holes 29a, 29b, 29c, and 29d formed in the bottom surface of the cylindrical lower portion 24c for each of the light emitting chambers 25a to 25d.

Each discharge hole 29a to 29d has a cathode 22 and each anode 2.
7a to 27d, and at least one of them, for example, the large diameter discharge hole 29d of the light emitting chamber 25d that emits blue (B) color, has a diameter that is larger than that of the other discharge holes 29a to 29c. The impedance of the discharge space within this large-diameter discharge hole 29d is lower than that of the other discharge holes 29a to 29c.

Further, the other discharge holes 29a to 29c are all formed to have approximately the same diameter.

A slight discharge current of, for example, 0.1 to 2% during lighting is constantly supplied to the cathode 22 and all the anodes 27a to 27d, so that a slight discharge always occurs between these electrodes 22, 27a to 27 (1). It is composed of

Next, the operation of this embodiment will be explained.

First, when the fluorescent lamp is turned off, a slight discharge current is constantly applied to the cathode 22 and all the anodes 27a to 27d.

Then, as shown in FIG. 4, the relative value of the slight discharge starting voltage with respect to this slight discharge current decreases as the diameter of the discharge holes 29a to 29d becomes larger. It is formed through a large diameter discharge hole 29d with a low height.

Next, due to the generation of this slight discharge, the impedance of the surrounding discharge space decreases, so this slight discharge moves to pass through each of the other small diameter discharge holes 29a to 29c, and in all the light emitting chambers 25a to 25d. A slight discharge occurs.

Since each of the discharge holes 29a to 29d does not have a luminescent film 26, it does not contribute to light emission, and moreover, the light-transmitting plate 28
When viewed from above, the negative glow around the cathode 22 is reflected in each discharge hole 2.
It is visually recognized as color noise through 9a to 29d.

This color noise occurs when the fluorescent lamp is turned off, so it may be noticeable.

Further, this color noise should be more visible as the diameter of the discharge holes 29a to 29d is larger, but since the large diameter discharge hole 29 is located in the blue (B) light emitting chamber 25d, the stray light is prevented from becoming noticeable. ing.

In other words, as shown in FIG. 5, blue (B) has a low standard-comparison luminous efficiency and is also the same color as the negative glow blue, so the negative glow is hardly noticeable and difficult to visually recognize.

In this way, the cathode 22 and all the anodes 27a to 27d
Since a slight discharge is constantly occurring between them and the impedance of the discharge space inside the envelope 20 is reduced, in order to light up this fluorescent lamp, an electric current is applied between the cathode 22 and all or each of the anodes 27a to 27d. The discharge starting voltage is significantly reduced.

In other words, a relatively low discharge starting voltage allows a slight discharge between the cathode 22 and the anodes 27a to 27d to smoothly transition to a main discharge, thereby lighting the fluorescent lamp.

〔Effect of the invention〕

As explained above, in the present invention, at least one of the plurality of discharge holes is made larger than the other discharge holes, so that the discharge starting voltage of the continuous slight discharge that occurs between the common electrode and the plurality of electrodes is reduced. can be done.

Therefore, according to the present invention, it is possible to lower the discharge starting voltage for transitioning from this slight discharge to the main discharge.

Further, at least one of the discharge holes may be made large and the others may be made small, so in this case, high brightness can be achieved with the small discharge hole.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of a fluorescent lamp according to the present invention;
Fig. 2 is a sectional view taken along line nn of Fig. 1, Fig. 3 is an exploded view of the embodiment shown in Figs. A graph showing the relationship between the size of the pore diameter, and Figure 5 is a graph showing the standard luminous efficiency of color.
FIG. 6 is a plan view of a conventional fluorescent lamp, FIG. 7 is a sectional view taken along the line ■--■ in FIG. 6, and FIG. 8 is a graph showing the relationship between the diameter of the discharge hole and the relative value of the discharge starting voltage. 20... Envelope, 22... Cathode (common electrode),
25a to 25d... Light emitting chamber, 26... Phosphor film, 2
78-27d...Anode (plurality of electrodes), 29a-
29c...Discharge hole, 29d...Large diameter discharge hole. Fig. 2 Fig. 3 Ei discharge electric north (1 station) Fig. 4 He ( Fig. 5 Fig. 6 IF5 Fig. 8

Claims (1)

[Claims] In a fluorescent lamp, a plurality of electrodes arranged opposite to a common electrode to perform discharge with the common electrode are respectively housed in a plurality of light emitting chambers, and a discharge hole through which the discharge passes is arranged in each light emitting chamber. At least one of the holes
A fluorescent lamp characterized in that one of the discharge holes is made larger than the other discharge holes, and the lamp is configured such that a slight discharge is constantly generated between the common electrode and the plurality of electrodes.