JPH02174096A - Rare gas discharge fluorescent lamp lighting method - Google Patents

Abstract

PURPOSE:To enable a high-luminance and high-efficiency lighting to be made by using argon as charging gas, giving the charging pressure of gas with its specific quantity, pulse impression time and an intermittent pulse impression time ratio respectively to a lamp, and intermittently lighting the lamp in such a condition like this. CONSTITUTION:A rare gas discharge fluorescent lamp has a phosphor screen formed almost all over the inner circumferential plane of its straight-shape cylindrical glass bulb 10 into which argon gas or krypton gas is charged and of which inside has a pair of electrodes 3a, 3b sealed at both-end portions. Also as the charged argon gas, a kind of gas having pressure ranging from 10Torr to 100Torr is used and then a pulsating voltage having the ration of its impression time to one cycle, being within 5 percent and 80 percent, and also having the impression time below 150 microseconds is impressed between both the electrodes 3a, 3b for making it possible to light the rare gas discharge fluorescent lamp. The pulsating voltage impression thus increases the probability of exciting the molecule of the charged gas, and then the lighting efficiency of the lamp becomes larger.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lighting system for rare gas discharge fluorescent lamps used in information equipment such as facsimiles, copying machines, and image readers.

[Conventional technology]

In recent years, with the advancement of the information society, information terminal equipment such as facsimiles, copiers, and image readers have become more sophisticated.
That market is rapidly expanding.

In developing this highly sophisticated information device, the light source unit used therein is required to have high performance as a key device. Conventionally, halogen lamps and fluorescent lamps have often been used as lamps for this light source unit. but.

Due to the low efficiency of halogen lamps, more efficient fluorescent lamps have been mainly used in recent years.

However, although fluorescent lamps have high efficiency, they use discharge of mercury vapor for light emission, so there is a problem that characteristics such as light output change depending on temperature. A heater was used to control the temperature. However, due to the diversification of usage locations and the increasing performance of 9 equipment, there has been a strong desire to develop fluorescent lamps with stable characteristics. Against this background, rare gas discharge fluorescent lamps have been developed as light sources for information equipment, which make full use of the light emitted by rare gas discharge, which does not change in temperature characteristics.

Figures 12 and 13 show a conventional rare gas discharge fluorescent lamp device disclosed, for example, in JP-A-63-58752. Figure 12 shows a cross section of the rare gas discharge fluorescent lamp and the device. A configuration diagram showing the overall configuration.

FIG. 13 is a longitudinal sectional view of the lamp. In the figure, il+
The bulb is in the shape of an elongated hollow rod and is made of quartz, hard or soft glass. A phosphor coating (2) is formed on the inner surface of this bulb (1),
The valve (1) is filled with a rare gas consisting of at least one of xenon, krypton, argon, neon, helium, and the like. Inside the bulb ill is a pair of internal electrodes (3a) located at both ends and having mutually different polarities;
(3b) is provided. These internal electrodes (3a)
, (+b) are connected to a lead wire (4) which passes through the end wall of the valve (1) in an airtight manner. Also, the valve (11
A band-shaped external electrode (5) is provided on the outer surface of the side wall of the electrode 5 in the axial direction.

The internal electrodes (3a) and (3b) are connected to a high-frequency inverter (as a high-frequency power generator) via lead wires (4).
8), and this high frequency inverter (8) is connected to a DC power source (9). The external electrode (5) is connected to the high frequency inverter (8) so as to have the same polarity as one of the internal electrodes (3a).

Next, the operation will be explained. In a rare gas discharge fluorescent lamp device having such a configuration, a high frequency inverter (8)
When high frequency power is applied between the internal electrodes (5a) and (3b) through these internal electrodes (3a).

(3b) Glow discharge occurs between. This glow discharge excites the rare gas in the bulb +11, and emits ultraviolet rays peculiar to rare gas. This ultraviolet light excites the phosphor coating (2) formed on the inner surface of the bulb (1), from which visible light is emitted.
It is released outside the valve il+.

In addition, as an example of other rare gas discharge fluorescent lamps, JP-A-63
There is one shown in Japanese Patent No.-248050.

This lamp was developed in order to improve the high starting voltage of cold cathode rare gas discharge lamps.
This uses the hot cathode electrode shown in the publication. This rare gas discharge fluorescent lamp can increase the power load, so the output can be increased. However, compared to mercury vapor fluorescent lamps, significantly lower efficiency and light output can be achieved.

[Problem to be solved by the invention]

As mentioned above, conventional rare gas discharge fluorescent lamps.

Since the phosphor is made to emit light by ultraviolet rays generated by rare gas discharge, it was not possible to obtain sufficient brightness and efficiency compared to mercury vapor fluorescent lamps.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a lamp lighting method for lighting a rare gas discharge fluorescent lamp with higher brightness and higher efficiency.

[Failure to solve the problem]

The rare gas discharge fluorescent lamp lighting method according to the present invention is a rare gas discharge fluorescent lamp in which argon gas of 10 Torr or more and 100 Torr or less is sealed in a glass bulb having a phosphor layer formed on the inner surface and a pair of electrodes at both ends. The rare gas discharge fluorescent lamp is lighted by applying a pulsed voltage between the two electric currents and the other electrodes, the ratio of the energization time to the cycle being 5% or more and 80 cm or less and one energization time of 150 μsec or less. It is something.

Also, the gas sealed inside the glass bulb.

In addition to replacing the above argon with krypton.

The rare gas discharge fluorescent lamp is lit by setting the ratio of the energization time in one cycle of the pulsed applied voltage to 5% or more and 70% or less.

[Effect]

In this invention, argon gas or krypton gas f
Enclosed at a pressure of Torr or more and 100 Torr or less,
And - the ratio of the current application time to the period is 80% or less in the case of argon gas, and 10% or less in the case of krypton gas, and the lighting is performed by applying a pulsed voltage with a current application time of 150 μsec or less.

By applying this pulsed voltage, the probability that the molecules of the filled gas will be excited at an energy level that will emit a large amount of resonance ultraviolet rays of the filled gas that contributes to light emission increases, and the light output and efficiency of the lamp increase. - Since the ratio f of the energization time during the cycle is set to 5% or more, wear and tear on the electrodes due to the application of pulsed voltage is suppressed.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram of an embodiment of the present invention. H is a rare gas discharge fluorescent lamp with a diameter of 15.5 all.

A phosphor film is formed on the entire inner peripheral surface of a straight cylindrical glass bulb with a length of 300 m, and argon gas or krypton gas is sealed inside the bulb. A pair of electrodes (3a), (
3b) is sealed. An aluminum plate three widths wide is glued to the outer wall of the bulb as a starting auxiliary conductor along the entire length of the lamp. (Iυ is a DC power supply and is the electrode (3a) of a rare gas fluorescent lamp.

(3b) and supplies DC voltage. O2 is FE
A switching element such as T is connected in parallel to a rare gas fluorescent lamp and has the function of turning on/off the DC voltage applied to the lamp. 0 is a pulse signal source, and the switching element Q3 performs switching according to the period and pulse width of the pulse emitted by the 0th pulse signal source, and converts the voltage applied to the rare gas discharge fluorescent lamp aω into a DC square wave pulse. This pulse voltage causes the lamp to be lit intermittently.

H is a resistor and is a light limiting element.

Next, in the rare gas discharge fluorescent lamp device described above, when the glass bulb α1 is completely filled with argon gas, the argon gas filling pressure inside the lamp during intermittent lighting of the lamp, - the ratio of the energization time during the cycle (hereinafter referred to as intermittent An experiment was conducted to measure the brightness and efficiency by changing the current application time, etc.

FIG. 2 shows the relationship between filler gas pressure and lamp efficiency. Note that the lamp efficiency is determined by dividing the luminance by the electric power. In Figure 2, (a) shows the case of square wave DC pulse lighting with an intermittent ratio of 60%, and (b) shows the case of normal high frequency AC lighting (sine wave), both values at a frequency of 20 kHz and the same power. It is. At a sealing pressure of 10 Torr or less, there is not much difference in efficiency between pulse lighting and AC lighting, but 1
It can be seen that above 0 Torr, the efficiency during pulse lighting exceeds the efficiency during AC lighting. Further, FIG. 3 shows the relationship between the charged gas pressure and the starting voltage, and it can be seen from this figure that as the gas filled pressure increases, a very high voltage is required for starting. Especially when the gas filling pressure is 100 Torr or higher, the starting voltage increases significantly, so the filling gas pressure is 100 Torr or more.
00 Torr or less is desirable.

Therefore, Figures 2 and 3 are more efficient than high-frequency lighting.
In addition, the optimal gas filling pressure for practical pulse lighting at the starting voltage is 10 Torr or more, 10 Torr or more.
It is below 0 Torr.

In addition, the diameter is 81 uI to 15.5 yuar', the length is 30011a (7), and the lamp is filled with argon gas and the pressure is 30
A large number of lamps were manufactured using Torr, and the characteristics of the lamps were measured by varying the DC pulse lighting conditions. The results are shown in FIGS. 4 and 5.

Figure 4 shows the relationship between the energizing time during one cycle of a DC pulse and the lamp efficiency.
The case where 5eC is constant is shown. From this figure, the shorter the pulse energization time, the better the efficiency.

It can be seen that the effect is particularly remarkable below 150 μ8 eC.

FIG. 5 shows the relationship between the lamp efficiency and the pulse intermittency ratio during pulse lighting at 20 kHz and 80 kHz.

Also shown are efficiency values during high frequency alternating current lighting (sine wave) of 20 kHz and 90 kHz, which are commonly used as comparison values ((e)(e)). As shown in Figure 5, DC lighting is achieved by reducing the pulse intermittency ratio (intermittent ratio 100%).
), and even when compared with AC lighting at the same frequency, it can be seen that if the pulse intermittency ratio is set to 80% or less, the efficiency increases significantly.

Furthermore, the diameter was 811 m to 15.5 was, and the argon gas filling pressure was changed from lQ Torr to 200 Torr.
A large number of lamps with a temperature of r were manufactured, and a life test was conducted on the lamps by changing the pulse intermittency ratio while keeping the lamp power constant. The results are shown in Figure 6. What is relative lifespan here?

It is the ratio of the average life time when lighting is performed at each intermittency ratio to the average life time when lighting is performed at a predetermined intermittency ratio (for example, 40%).The relationship between the pulse intermittency ratio and the relative life is
As shown in the figure, as the pulse intermittency ratio is decreased, the pulse intermittency ratio becomes 5.
%, the relative life shows a slight tendency to decrease, and at a small intermittent ratio of 5% or less, the life rapidly decreases. 5
% or less, it is estimated that the pulse peak current of the lamp becomes large and the wear of the electrodes rapidly progresses. Therefore, the pulse intermittency ratio is desirably 5% or more in consideration of life.

Also, as an invention different from those shown in 9 and above.

An example in which krypton gas is sealed in the glass bulb α1 will be shown below. Note that the overall configuration diagram in this case is the same as that shown in FIG.

FIG. 7 shows the relationship between the krypton gas sealing pressure and lamp efficiency. In Figure 7, (a) shows the case of square wave DC pulse lighting with an intermittent ratio of 60%, and (b) shows the case of normal high frequency AC lighting (sine wave), both values at a frequency of 20 kHz and the same power. It is. At a sealing pressure of 10 Torr or less, there is not much difference in efficiency between pulse lighting and AC lighting, but +
It can be seen that at temperatures above 10 Torr, the efficiency during pulse lighting exceeds the efficiency during AC lighting.

In addition, Fig. 8 shows the relationship between the filled gas pressure and the starting voltage.
From FIG. 8, it can be seen that as the pressure of krypton gas increases, a very high voltage is required for starting. Especially when the gas filling pressure is 100 Torr or more, the starting voltage increases significantly, so the filling gas pressure should be 100 Torr or more.
The following is desirable.

Therefore, as shown in Figures T and 8, the optimal gas filling pressure is 10 Torr or more in order to perform pulse lighting, which is more efficient than high-frequency lighting and practical at a starting voltage of 10 Torr.
It is 0 Torr or less.

In addition, a large number of lamps with a diameter of 8 ws to 15.5 m and a length of 300 mm were manufactured with a total carbon gas filling pressure of 30 Torr, and the characteristics of the lamps were measured by varying the DC pulse lighting conditions. The results are shown in FIGS. 9 and 10.

Figure 9 shows the relationship between the energization time and lamp efficiency during one cycle of a DC pulse, and the non-energization time t-100.
The case where μ5ec is constant is shown.

From this figure, the shorter the pulse energization time, the better the efficiency.

It can be seen that the effect is particularly remarkable at 150 μsec or less.

Figure 10 shows the relationship between lamp efficiency and pulse intermittency ratio during pulse lighting at 20 kHz and 80 kHz (see e9).
.

In addition, as comparison values, the efficiency values when high-frequency AC lighting (sine wave) of 20 kHz and 80 kHz, which are commonly used, are also shown ((e)(e)). Figure 10 shows the pulse intermittent ratio. By making it smaller, DC lighting (intermittent ratio 100%)
) The efficiency increases significantly over time, and even when compared with AC lighting at the same frequency, it can be seen that the efficiency increases significantly when the pulse intermittent ratio i is set to 70% or less.

Furthermore, a number of lamps with diameters ranging from 8mm to 15.5M and chlorine gas filling pressures ranging from 10 Torr to 200 Torr were manufactured, and life tests were conducted on these lamps by varying the pulse intermittency ratio while keeping the lamp power constant.

The results are shown in FIG. 11. From FIG. 11, as the pulse intermittency ratio is decreased, the relative life tends to decrease slightly up to a pulse intermittency ratio of 5.

It can be seen that at a small intermittent ratio of 5% or less, the life span decreases rapidly. It is estimated that if it is less than 5%, the pulse peak current of the lamp becomes large and the wear of the electrodes rapidly progresses. Therefore, the pulse intermittency ratio is desirably 5% or more in consideration of life.

In each of the above embodiments, an example of direct current pulse lighting is shown as an example of pulsed intermittent lighting.

It has been confirmed from the experiments of the above-mentioned Examples that the same effect can be obtained by intermittent lighting using alternating current pulses as the intermittent lighting.

〔Effect of the invention〕

As described above, according to the present invention, the sealed gas is argon, and the sealed pressure is 10 Torr or more.

jQQ Torr or less, total pulse energization time 150
The lighting method allows the lamp to be lit intermittently under the conditions that the intermittent ratio of less than 9 μsec is 5- or more and less than 80%, so it can achieve high brightness without shortening the life compared to conventional DC lighting or normal high-frequency AC lighting. This has the effect of providing a highly efficient rare gas discharge fluorescent lamp.

According to another invention, the same effect can be obtained by using krypton gas as the filler gas and setting the intermittent ratio to 5% or more and 70% or less.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of a rare gas discharge fluorescent lamp device showing an embodiment of the present invention, Fig. 2 is a lamp efficiency characteristic diagram depending on the argon gas filling pressure in the device, and Fig. 3 is a startup diagram based on the argon gas filling pressure. Voltage characteristic diagram, Figure 4 is a lamp efficiency characteristic diagram according to pulse energization time, Figure 5 is a lamp efficiency characteristic diagram according to pulse intermittency ratio, Figure 6 is a life characteristic diagram according to pulse intermittency ratio, and Figure 7 is another diagram. Lamp efficiency characteristic diagram according to krypton gas filling pressure in an embodiment of the invention,
Fig. 8 is a starting voltage characteristic diagram depending on the krypton gas filling pressure, Fig. 9 is a lamp efficiency characteristic diagram depending on the pulse energization time of the device, Fig. 10 is a lamp efficiency characteristic diagram depending on the pulse intermittency ratio of the device, and Fig. 11 12 is a diagram showing the lifetime characteristics of the device according to the pulse intermittency ratio, FIG. 12 is an overall configuration diagram of a conventional rare gas discharge fluorescent lamp device, and FIG. 13 is a longitudinal sectional view of the lamp. In the figure, (3a) and (+b) are electrodes, H is a glass bulb, aυ is a DC power supply, and α2 is a switching element. (13 is a pulse signal source. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) A glass bulb with a phosphor layer formed on the inner surface and a pair of electrodes at both ends has a temperature of 10 Torr or more and 100 Torr.
A rare gas discharge fluorescent lamp is constructed by filling argon gas with an amount of less than A method for lighting a rare gas discharge fluorescent lamp, characterized in that the rare gas discharge fluorescent lamp is turned on by (2) A glass bulb with a phosphor layer formed on the inner surface and a pair of electrodes at both ends has a temperature of 10 Torr or more and 100 Torr.
A rare gas discharge fluorescent lamp is constructed by enclosing krypton gas with an amount of less than A method for lighting a rare gas discharge fluorescent lamp, characterized in that the rare gas discharge fluorescent lamp is turned on by