JPH0812795B2 - Lighting method of rare gas discharge fluorescent lamp - Google Patents

Description

The present invention relates to a method for lighting a rare gas discharge fluorescent lamp used in information equipment such as facsimiles, copying machines, and image readers.

[Conventional technology]

In recent years, with the progress of the information society, information terminal devices such as facsimiles, copying machines, and image readers have become more sophisticated, and the market for them has expanded rapidly. In developing this high-performance information device, the light source unit used in it is required to have high performance as a key device. Conventionally, halogen lamps and fluorescent lamps have been widely used as the lamps used in this light source unit. However, halogen lamps have recently been mainly used for efficient fluorescent lamps due to their poor efficiency.

However, while fluorescent lamps are highly efficient, they use the discharge of mercury vapor for light emission, so they have the problem that characteristics such as light output change with temperature. Therefore, the operating temperature range is limited or the lamp wall I used a heater to control the temperature. However, the development of fluorescent lamps with stable characteristics has been strongly desired due to the diversification of places of use and higher performance of equipment. From such a background, a rare gas discharge fluorescent lamp utilizing light emission by a rare gas discharge that does not change in temperature characteristics has been developed as a light source for information equipment.

FIGS. 12 and 13 show a conventional rare gas discharge fluorescent lamp device disclosed in, for example, Japanese Patent Laid-Open No. 63-58752, and FIG. 12 shows a cross section of the rare gas discharge fluorescent lamp and the device. Fig. 13 is a vertical sectional view of the lamp, showing the overall structure. In the figure, (1) is an elongated hollow rod-shaped bulb, which is made of quartz or hard or soft glass. A phosphor coating (2) is formed on the inner surface of the bulb (1), and a rare gas containing at least one of xenon, krypton, argon, neon, helium, etc. is enclosed in the bulb (1). ing. Inside the valve (1), a pair of internal electrodes (3a), (3b) located at both ends and having different polarities are provided. These internal electrodes (3a), (3b) are connected to a lead wire (4) that hermetically penetrates the end wall of the valve (1). A strip-shaped external electrode (5) is provided on the outer surface of the side wall of the bulb (1) along the axial direction.

The internal electrodes (3a), (3b) are connected to a high frequency inverter (8) as a high frequency power generator via a lead wire (4), and the high frequency inverter (8) is connected to a DC power source (9). ing. And external electrodes (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 described. In the rare gas discharge fluorescent lamp device having such a structure, when high-frequency power is applied between the inner electrodes (3a) and (3b) through the high-frequency inverter (8), the glow is generated between these inner electrodes (3a) and (3b). Electric discharge occurs. This glow discharge excites the rare gas in the bulb (1) and emits ultraviolet rays peculiar to the rare gas. This ultraviolet ray excites the phosphor coating (2) formed on the inner surface of the bulb (1), from which visible light is emitted and emitted to the outside of the bulb (1).

In addition, as an example of another rare gas discharge fluorescent lamp, Japanese Patent Laid-Open No.
There is one disclosed in -248050. This lamp uses a hot cathode electrode as disclosed in, for example, Japanese Patent Publication No. 63-29931, in order to improve the drawback of the cold cathode rare gas discharge lamp having a high starting voltage. Since the power of the rare gas discharge fluorescent lamp can be increased, the output can be increased. However, it can obtain much lower efficiency and light output than fluorescent lamps using mercury vapor.

[Problems to be Solved by the Invention]

As described above, since the conventional rare gas discharge fluorescent lamp emits the fluorescent substance by the ultraviolet rays generated by the rare gas discharge, it cannot obtain sufficient brightness and efficiency as compared with the mercury vapor fluorescent lamp. It was

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

[Means for solving the problem]

A method of lighting a rare gas discharge fluorescent lamp according to the present invention,
A rare gas discharge fluorescent lamp is constructed by enclosing argon gas of 10 Torr or more and 100 Torr or less in a glass bulb having a phosphor layer formed on the inner surface and a pair of electrodes at both ends, and the ratio of energization time to one cycle is 5 % And 80% or less, and a pulsed voltage having an energization time of 150 μsec or less is applied between the electrodes to turn on the rare gas discharge fluorescent lamp.

Further, the gas sealed in the glass bulb is krypton instead of the argon, and the ratio of the energization time in one cycle of the pulsed applied voltage is set to 5% or more and 70% or less to produce a rare gas discharge fluorescent lamp. It is designed to light up.

[Work]

In the present invention, argon gas or krypton gas is supplied in the glass bulb at 10 Torr so as to be suitable for intermittent lighting.
Enclose at a pressure of 100 Torr or more, and the energization time per cycle is 80% or less for argon gas, 70% or less for krypton gas, and apply a pulsed voltage for energization time of 150 μsec or less to turn on. By applying this pulsed voltage, the probability that the molecules of the enclosed gas will be excited at an energy level that emits a large number of resonance ultraviolet rays of the enclosed gas that contribute to light emission will increase the light output of the lamp. Since the efficiency is increased and the ratio of the energization time in one cycle is set to 5% or more, the wear of the electrode due to the application of the pulsed voltage is suppressed.

Example of 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.
(10) is a rare gas discharge fluorescent lamp with a diameter of 15.5 mm and a length of 300.
A phosphor film is formed on almost the entire inner peripheral surface of a glass cylinder with a straight cylindrical shape of mm, and argon gas or krypton gas is enclosed in the bulb. Valve (1
A pair of electrodes (3a) and (3b) are sealed at both ends in (0). An aluminum plate with a width of 3 mm is adhered to the outer wall of the bulb as a starting auxiliary conductor over the entire length of the lamp. (11) is a DC power supply, which is connected to the electrodes (3a) and (3b) of the rare gas fluorescent lamp and supplies a DC voltage. (1
2) is a switching element such as FET, which is connected in parallel with the rare gas fluorescent lamp and has the function of turning on / off the DC voltage applied to the lamp. (13) is a pulse signal source,
The switching element (12) performs switching with the period and pulse width of the pulse generated by the pulse signal source (13), and has the function of converting the voltage applied to the rare gas discharge fluorescent lamp (10) into a DC rectangular wave pulse. The lamp is intermittently turned on by the pulse voltage. (14) is a resistor, which is a current limiting element.

Next, in the rare gas discharge fluorescent lamp device described above,
When the glass bulb (10) is filled with argon gas, the argon gas filling pressure in the lamp during intermittent lighting of the lamp, the ratio of the energization time during one cycle (hereinafter referred to as the intermittent ratio), the energization time, etc. An experiment was conducted to measure the efficiency.

FIG. 2 shows the relationship between the charged gas pressure and the lamp efficiency. The lamp efficiency is obtained from the value obtained by dividing the brightness by the power. In Fig. 2, (a) shows the case of square wave direct current pulse lighting with an intermittent ratio of 60%, (b) shows the case of normal high frequency alternating current lighting (sine wave), both with a frequency of 20 kHz and the same power value. is there. When the filling pressure is 10 Torr or less, pulse lighting
Although there is not much difference in efficiency with AC lighting, it can be seen that the efficiency with pulse lighting exceeds that with AC lighting above 10 Torr. Further, FIG. 3 shows the relationship between the charged gas pressure and the starting voltage. From this figure, it can be seen that when the gas charging pressure becomes high, a very high voltage is required for starting. Especially when the gas charging pressure is 100 Torr or more, the starting voltage rises significantly, so it is desirable that the gas charging pressure be 100 Torr or less. Therefore, as shown in FIGS. 2 and 3, the optimum gas charging pressure is 10 Torr or more and 100 Torr or less, which is more efficient than high-frequency lighting and has a practical pulse lighting at the starting voltage.

In addition, many lamps with diameters from 8 mm to 15.5 mm and lengths of 300 mm were manufactured with an argon gas filling pressure of 30 Torr, and the lamp characteristics were measured under various DC pulse lighting conditions. Fourth
The results are shown in Figs.

Figure 4 shows the relationship between the energization time and the lamp efficiency during one DC pulse cycle. The de-energization time is 100 μs.
It shows the case where ec is constant. From this figure, it can be seen that the shorter the pulse energization time, the higher the efficiency, and that the effect is particularly remarkable at 150 μsec or less.

Fig. 5 shows the relationship between the lamp efficiency and the pulse intermittence ratio during pulse lighting at 20 kHz and 80 kHz ((c) and (d)).

Also, as comparative values, the efficiency values during high-frequency AC lighting (sine wave) of 20 kHz and 80 kHz that are normally used are also shown ((e) (f)). As shown in Fig. 5, by reducing the pulse intermittent ratio, the efficiency is significantly increased compared to when DC lighting (intermittent ratio 100%), and even when compared to AC lighting of the same frequency, the pulse intermittent ratio is 80%. It can be seen that if it is less than or equal to%, the efficiency is greatly exceeded.

Furthermore, the diameter of 8mm to 15.5mm, the argon gas filling pressure
We manufactured many lamps from 10 Torr to 200 Torr, and performed a life test on these lamps while keeping the lamp power constant and changing the pulse intermittent ratio. Results are shown in FIG. Here, the relative life is the ratio of the average life time when lighting at each intermittent ratio to the average life time when lighting at a predetermined intermittent ratio (for example, 40%). The relationship between the pulse intermittence ratio and the relative life is shown in Fig. 6. As the pulse intermittence ratio is reduced, the relative life tends to decrease slightly up to a pulse intermittence ratio of 5%.
It can be seen that the life shortens sharply with a small intermittent ratio of less than%. If it is less than 5%, the pulse peak current of the lamp becomes large, and it is presumed that the wear of the electrodes rapidly progresses.
Therefore, the intermittent ratio of the pulse is preferably 5% or more in consideration of the life.

In addition, as another invention different from the one described above, an example of enclosing krypton gas in the glass bulb (10) will be shown below. The overall configuration in this case is the same as that shown in FIG.

FIG. 7 shows the relationship between the filling pressure of krypton gas and the lamp efficiency. In Fig. 7, (a) shows the case of square wave direct current pulse lighting with an intermittent ratio of 60%, (b) shows the case of normal high frequency alternating current lighting (sine wave), both with a frequency of 20 kHz and the same power value. is there. When the filling pressure is 10 Torr or less, pulse lighting
Although there is not much difference in efficiency with AC lighting, it can be seen that the efficiency with pulse lighting exceeds that with AC lighting above 10 Torr.

Further, FIG. 8 shows the relationship between the charged gas pressure and the starting voltage. From this FIG. 8, it can be seen that when the charged pressure of krypton gas increases, a very high voltage is required for starting. Especially when the gas charging pressure is 100 Torr or more, the starting voltage rises significantly, so it is desirable that the gas charging pressure be 100 Torr or less. Therefore, as shown in Figs. 7 and 8, the optimum gas charging pressure is 10 Torr, which is more efficient than high-frequency lighting and has a practical pulse lighting at the starting voltage.
Above, it is below 100 Torr.

Also, many lamps with a diameter of 8 mm to 15.5 mm and a length of 300 mm were manufactured at a krypton gas charging pressure of 30 Torr, and the characteristics of the lamp were measured under various DC pulse lighting conditions. The results are shown in FIGS. 9 and 10.

Figure 9 shows the relationship between the energization time and the lamp efficiency during one DC pulse cycle. The de-energization time is 100 μs.
It shows the case where ec is constant. From this figure, it can be seen that the shorter the pulse energization time, the higher the efficiency, and that the effect is particularly remarkable at 150 μsec or less.

Figure 10 shows the relationship between the lamp efficiency and the pulse intermittence ratio during pulse lighting at 20 kHz and 80 kHz ((c) and (d)).

Also, as comparative values, the efficiency values during high-frequency AC lighting (sine wave) of 20 kHz and 80 kHz that are normally used are also shown ((e) (f)). As shown in Fig. 10, by reducing the pulse intermittency ratio, the efficiency is significantly increased compared to that during direct current lighting (intermittent ratio 100%), and even when compared with alternating current lighting at the same frequency, the pulse intermittency ratio is 70%. It can be seen that if it is less than or equal to%, the efficiency is greatly exceeded.

Furthermore, many lamps with diameters of 8 mm to 15.5 mm and krypton gas filling pressures of 10 Torr to 200 Torr were manufactured, and a life test was performed by changing the pulse intermittence ratio while keeping the lamp power constant. The results are shown in Fig. 11. From Fig. 11, when the pulse intermittence ratio is reduced, the relative life tends to decrease slightly up to a pulse intermittency ratio of 5%, and sharply decreases with a small intermittency ratio of 5% or less. It can be seen that the life is shortened. If it is less than 5%, the pulse peak current of the lamp becomes large, and it is presumed that the wear of the electrodes rapidly progresses. Therefore, the intermittent ratio of the pulse is preferably 5% or more in consideration of the life.

In each of the above examples, the example of DC pulse lighting was shown as an example of pulse-like intermittent lighting, but it was confirmed from the experiments of the above-mentioned examples that the same effect can be obtained by intermittent lighting of AC pulses as intermittent lighting. Was done.

〔The invention's effect〕

As described above, according to the present invention, the filling gas is argon, and the filling pressure is 10 Torr or more and 100 Torr or less,
Pulse energization time is 150 μsec or less, intermittent ratio is 5% or more, 8
Since the lighting method is such that the lamp is intermittently lit under the condition of 0% or less, a high-intensity, high-efficiency rare gas discharge fluorescent lamp can be provided without shortening the life as compared with conventional DC lighting or normal high-frequency AC lighting. It has the effect of being obtained.

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

[Brief description of drawings]

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 according to the argon gas charging pressure in the device, and FIG. 3 is a starting by the argon gas charging pressure. Fig. 4 is a voltage characteristic diagram, Fig. 4 is a lamp efficiency characteristic diagram by pulse energization time, Fig. 5 is a lamp efficiency characteristic diagram by pulse intermittent ratio, Fig. 6 is a life characteristic diagram by pulse intermittent ratio, and Fig. 7 is another The lamp efficiency characteristic diagram by the krypton gas charging pressure in one embodiment of the invention,
FIG. 8 is a characteristic diagram of the starting voltage due to the krypton gas charging pressure, FIG. 9 is a characteristic diagram of the lamp efficiency according to the pulse energization time of the device, FIG. 10 is a characteristic diagram of the lamp efficiency according to the pulse intermittent ratio of the device, and FIG. Is a life characteristic diagram based on the pulse intermittence ratio of the device, FIG. 12 is an overall configuration diagram of a conventional rare gas discharge fluorescent lamp device, and FIG. 13 is a vertical sectional view of the lamp. In the figure, (3a) and (3b) are electrodes, (10) is a glass bulb, (11) is a DC power supply, (12) is a switching element,
(13) is a pulse signal source. The same reference numerals in each figure indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-34897 (JP, A) JP-A-63-58752 (JP, A) JP-B-58-20478 (JP, B2)

Claims (2)

[Claims] 1. A rare gas discharge fluorescent lamp is constructed by enclosing argon gas of 10 Torr or more and 100 Torr or less in a glass bulb having a phosphor layer formed on the inner surface and a pair of electrodes on both ends, and energizing for one cycle. A method for lighting a rare gas discharge fluorescent lamp, characterized in that a pulsed voltage having a time ratio of 5% or more and 80% or less and an energization time of 150 μsec or less is applied between the electrodes to light the rare gas discharge fluorescent lamp. . 2. A rare gas discharge fluorescent lamp is constructed by enclosing krypton gas of 10 Torr or more and 100 Torr or less in a glass bulb having a phosphor layer formed on the inner surface and a pair of electrodes at both ends, and energizing for one cycle. 5% of time
A method of lighting a rare gas discharge fluorescent lamp, characterized in that a pulsed voltage of 70% or less and an energization time of 150 μsec or less is applied between the electrodes to light the rare gas discharge fluorescent lamp.