JPS6314399Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a discharge lamp device using a flat plate-shaped low-pressure discharge lamp with a flat tube cross section.

When considering a fluorescent lamp as a planar light source, it is generally of the combined type with type glass to obtain a meandering discharge path _B1 as shown in Fig. 1, or with electrodes f, as shown in Fig. 2, as in a normal lamp. It is conceivable to arrange the lamps facing each other, but in the lamp shown in Fig. 1, the fabrication of the molded glass and the combination sealing process are extremely complicated, which poses a major difficulty in manufacturing, and the lamp shown in Fig. 2 In the type shown in
_B2 only takes the shortest path that minimizes the discharge energy, but it has the disadvantage that the area around the lamp is dark and uniform brightness cannot be obtained on the flat surface.

The present invention has been devised in view of the above, and its purpose is to provide a discharge lamp device in which the entire flat-type low-pressure discharge lamp appears to emit light uniformly.

Hereinafter, the present invention will be explained based on examples. Third
The figure is a diagram schematically showing an embodiment of the flat plate type low pressure discharge lamp device according to the present invention, in which the inner surface of the flat plate type lamp FL is coated with phosphor, and the anodes A1 and ₁ are arranged at both ends of the lamp. Two sets of opposing electrodes are provided, consisting of a cathode K ₁ and an anode A ₂ and a cathode K ₂ . In addition, AC in the figure
is an AC power supply of 40Hz or higher, D ₁ , D ₂ , D ₃ , and D ₄ are each rectifiers, and CH is a current-limiting choke coil.

Now, if the AC power supply AC has the polarity shown in Figure ₃ , the rectifiers D ₁ to _{D 4}
→Anode A ₁ →Cathode K ₁ →Rectifier D ₂ →Chiyoke coil
Only the circuit that goes through the CH can light up, and one counter electrode
A discharge occurs only at A ₁ →K ₁ , and the surrounding area emits light as shown by the shaded area a in the figure.

Then the alternating current power supply AC is reversed, anode A ₁ → cathode K ₁
When the current tries to reverse, the discharge in the direction of cathode K ₁ → anode A ₁ no longer occurs because of the rectifiers D ₁ and D ₂ , and the discharge in the direction of CH Yoke coil CH → rectifier D ₃ → anode A ₂ →
A discharge occurs from the counter electrode A ₂ →K ₂ via the cathode K ₂ →rectifier D ₄ , and light is emitted as shown in the shaded area b in the figure.

In this way, by reversing the alternating current power supply AC, area a,
Area b will emit light alternately, but because the inversion cycle is set to 40Hz or higher, the alternating brightness and darkness of the light is difficult for the human eye to perceive, and it appears as if both areas a and b are glowing. Visually, the entire lamp appears to emit light uniformly, and in practice it shows the effect of uniform light emission. Incidentally, the flickering sensation in the eyes with respect to frequency has a relationship as roughly shown in FIG. 4, and if the AC power source AC is lower than 40 Hz, an unpleasant flickering sensation will be felt with a peak frequency of 5 to 10 Hz, which is practically inconvenient.

In general use, if the inversion cycle is 40Hz or more as mentioned above, there is virtually no flickering sensation, but especially when viewing only the vicinity of the electrode diagonally, human visual perception often deteriorates. Will my senses become sharper?
You may notice some flickering at the edges. This end-flicker feeling occurs up to 100Hz at most.
I can't feel anything beyond that. Therefore, if the inversion period is set to 100 Hz or more, end flickers can also be removed.

Next _, FIGS. 5 to 7 show different embodiments of the present invention. In the _embodiment shown in FIG _. It has exactly the same shape as A _2. In this case, it generally becomes a cold cathode glow discharge, and the voltage of the AC power source AC and the lamp voltage become high.

In the device shown in FIG. 6, the cathodes K ₁ and K ₂ are hot cathodes that facilitate thermionic emission, and in this case, the rectifiers D ₁ to _{D 4} may be unnecessary. this is,
When trying to reverse the discharge from anode A ₁ → cathode K ₁ ,
This is because the anode A ₁ cannot be a hot cathode, so the discharge automatically reverses from the anode A ₂ to the cathode K ₂ .
However, in some cases, discharge may occur from the cathode K ₁ to the cathode K ₂ , so the above example (shown in Fig. 3)
It is unstable compared to .

In the circuit shown in FIG. 7, four pairs of opposing electrodes are arranged, and a lighting circuit is configured such that adjacent opposing electrodes alternately cause inversion discharge. In such a case, if the length in the lateral direction (direction perpendicular to the interelectrode direction) is sufficiently large compared to the thickness of the cross section of the flat lamp FL, the discharge from anode A ₁ → cathode K ₁ and anode A ₃ → cathode K ₃
Although two discharges can occur at the same time, a partition wall portion (or separator gap) B may be provided as shown in the figure in order to cause more reliable discharge. Furthermore, one current-limiting choke coil may be provided in each discharge path in order to further stabilize and adjust the discharge. Of course, they can also be coupled to balance the currents between them.

Next, FIG. 8 is a sectional view showing a different embodiment of the flat lamp used in the present invention, in which different types of phosphors a ₁ and b ₁ are used as the phosphors coated on the inner surface of the lamp. For example, the phosphor a ₁ is calcium halophosphate that emits white light with a color temperature of about 4200, and the phosphor b _{1 is}
When the lamp is made of yttrium oxide which emits red light and is turned on with the circuit configuration as shown in the above embodiment (Fig. 3), white light is emitted from the discharge path a side and red light is emitted from the discharge path b side. , one lamp can easily provide light of different colors, and variable illumination can be obtained. Incidentally, the inversion period of the discharge may be set to an appropriate period in order to obtain a desired illumination effect.

Furthermore, what is shown in FIG.
Dimmers S ₁ and S ₂ were added to the one shown in the figure, and by operating these dimmers S ₁ and S ₂ , the current flowing through each discharge path a and b can be adjusted, and the emitted color can be changed. It is something that brings about change.

For example, if the currents in the discharge paths a and b are made to be the same, the intensities of the red and white light emission will be approximately the same, and a single lamp that emits different colors at the same time can be obtained. The current in a is discharge path b
If you adjust the current with the dimmers S ₁ and S ₂ so that it is larger than the current in discharge path B, you can obtain strong white light, and conversely, if you adjust the current in discharge path b to be larger than the current in discharge path a, you can obtain illumination with strong white light. , strong red light emission can be obtained. Furthermore,
Needless to say, if the current in either one of the discharge paths a and b is made zero, illumination with only red or white monochromatic light can be obtained.

[Brief explanation of drawings]

Figures 1 and 2 show conventional flat fluorescent lamps, in which a is a simplified plan view;
b is a simplified cross-sectional view. FIG. 3 is a diagram schematically showing an embodiment of the present invention, FIG. 4 is a diagram showing the flicker feeling with respect to frequency, and FIGS. 5 to 9 are diagrams showing different embodiments of the present invention. Figures 5, 6, 7a and 9 are schematic diagrams, Figure 7b is a simplified sectional view of the lamp used in Figure 7a, and Figure 8 is a diagram of the lamp coated with different types of phosphors. It is a simplified cross-sectional view.

Claims (1)

[Claims for Utility Model Registration] (1) A flat plate-shaped low-pressure discharge lamp with a flat tube cross section, which is provided with a plurality of sets of opposing electrodes at both ends, characterized by sequentially inverting discharge between adjacent opposing electrodes. Flat plate type low pressure discharge lamp device. 2. The flat plate low-pressure discharge lamp device according to claim 1, characterized in that the period of the reverse discharge is 40 Hz or more.