JP6103730B2 - Gas discharge light emitting device - Google Patents

Description

  The present invention relates to a gas discharge light emitting device.

  Conventionally, high-pressure mercury lamps and excimer discharge lamps are well known as light source devices using gas discharge. As an ultraviolet light source, a gas discharge device using an ultraviolet light emitting phosphor is known (for example, see Patent Document 1). Furthermore, an external electrode type gas discharge device having a narrow tube configuration suitable for the configuration of a planar light source is also well known (see, for example, Patent Documents 2 and 3).

Japanese Patent No. 5074381 Japanese Patent Laid-Open No. 2004-170074 Japanese Patent Application Laid-Open No. 2011-040271

  Conventional excimer discharge lamps using ultraviolet phosphors have problems such as using an expensive quartz glass envelope and requiring a high-voltage square-wave AC power source for driving. Moreover, the conventional gas discharge device for ultraviolet light emission using a gas discharge tube has a complicated electrode structure, and has not yet reached a practical range in terms of light emission efficiency and light output.

  The present invention has been made in consideration of such circumstances, and provides a gas discharge light-emitting device for a light source that has a simple structure, is easy to assemble and repair, and has high luminous efficiency, in particular, an ultraviolet light source. is there. In addition, the present invention provides a new flat light source for ultraviolet light emission of a touch contact type in which an arc tube and an electrode member are configured as independent parts.

  Briefly speaking, the present invention relates to an arc tube assembly (assembly) that does not have an electrode made of a glass thin tube and an electrode assembly (assembly) that applies an alternating drive voltage to the arc tube assembly as independent parts. The idea is to provide a new type of gas discharge light emitting device by constructing and overlaying both in a detachable touch contact format.

  The electrode pair of the electrode assembly is disposed on the back surface or the surface of the insulating substrate with a pattern of long electrodes extending on both sides across the discharge gap in the longitudinal direction of the arc tube with the arc tube mounted thereon. The

  When an alternating drive voltage such as a sine waveform or ramp waveform is applied between a pair of long electrodes, the first trigger discharge that occurs between the adjacent electrodes of the electrode as the voltage rises becomes a seed, and then the length of the gradual electrode is increased. As the discharge expands in the direction, efficient light emission over the entire length of the arc tube can be obtained.

  More specifically, the first feature of the present invention is composed of an arc tube assembly composed of a glass tube filled with a discharge gas, and an electrode assembly in which at least a pair of discharge electrodes are arranged on an insulating substrate. The gas discharge light emitting device has a touch contact configuration in which the arc tube assembly is detachably mounted on the electrode assembly. Here, the touch contact means that both assemblies are held in physical contact with each other.

  As the glass thin tube, a transparent glass thin tube having a circular, elliptical, flat elliptical, rectangular or trapezoidal shape with a major axis diameter of 5 mm or less is preferably used, and the length is suitably 2 cm to 10 cm. Depending on the application, it may be longer.

  In addition, even if borosilicate glass, which is much cheaper and more popular than quartz glass, is used as the glass thin tube in the case of constituting an ultraviolet light source, the thickness of the tube on the surface side that becomes the light emitting surface should be 300 μm or less. As a result, sufficient ultraviolet transmitted light can be obtained.

  In the electrode assembly, the first electrode and the second electrode constituting the electrode pair extend in the longitudinal direction of the glass tube when the arc tube assembly is placed on both ends of the gap between the gaps. The proximate ends constitute a trigger discharge part, and both side extension parts are provided with a long electrode pattern constituting a main discharge part. In this configuration, the first and second electrodes are alternately arranged in series in the longitudinal direction of the glass thin tube so that there are a plurality of the electrode pairs, thereby making it possible to cope with the lengthening of the arc tube. The long electrodes to be paired preferably have a length at least three times the gap length at the proximal end along the longitudinal direction of the arc tube.

  An inner surface of the glass tube is provided with an ultraviolet light-emitting phosphor layer that emits light when excited by vacuum ultraviolet light generated by discharge of a xenon mixed gas, or a visible light-emitting phosphor layer, or a mixed phosphor layer thereof. Can be obtained.

  Further, according to the present invention, a flexible planar light source is formed by stacking an arc tube assembly in which a plurality of arc tubes having the glass thin tube structure are arranged in parallel and an electrode assembly having a common electrode pair in each arc tube. Can be configured. A plurality of arc tubes having different emission wavelengths may be combined and arranged to form a surface light source having multiple emission wavelengths.

  Further, according to the second feature of the present invention, an arc tube comprising a drive circuit assembly mainly composed of a printed circuit board on which circuit components are mounted, and a glass thin tube having a phosphor layer therein and filled with a discharge gas. A light source module in which a plurality of arc tube assemblies arranged side by side are stacked with an electrode assembly having at least one pair of discharge electrodes interposed therebetween, and the arc tube assembly and the electrode assembly The body is a touch contact configuration in which the discharge electrode pair is releasably overlapped with the arc tube so as to face each other with a long electrode pattern extending on both sides from a proximal end portion forming a discharge gap along the longitudinal direction of the arc tube. A gas discharge light emitting device is provided.

  According to the present invention, the arc tube assembly itself does not have an electrode, and the electrode assembly has a simple structure in which a conductive film such as an aluminum foil is formed in a solid pattern on an insulating substrate. Is obtained. In addition, the arc tube assembly and the electrode stand are configured independently, and the discharge gap length is automatically determined simply by placing the arc tube in a direction across the electrode gap that forms a pair of electrode assemblies. Of course, it is very easy to replace and repair the arc tube due to breakage or deterioration.

  Furthermore, the present invention utilizes a new type of discharge generated by applying an alternating drive voltage from a pair of long electrodes positioned along the longitudinal direction of the arc tube made of a glass thin tube, In the configuration in which the ultraviolet light-emitting phosphor layer is provided in the glass capillary tube, it is possible to obtain ultraviolet light with high efficiency and high intensity as compared with the conventional ultraviolet light-emitting LED.

  In addition, a large-area, high-output ultraviolet plane light source can be easily configured by arranging a plurality of ultraviolet arc tubes, making it a mercury-free ultraviolet light source for medical use, sterilization / sterilization use, exposure use, and plant growth. The application range such as irradiation applications will be greatly expanded.

1 is a longitudinal sectional view and a transverse sectional view showing a basic configuration of a gas discharge light emitting device according to the present invention as Embodiment 1; It is a schematic diagram which shows the discharge model of Embodiment 1 of the gas discharge light-emitting device by this invention in time series. It is the top view and sectional drawing which show the structure of the planar light source by Embodiment 2 of the gas discharge light-emitting device by this invention. It is the top view and principal part sectional drawing which show the structure of the large sized planar light source by Embodiment 3 of this invention. It is sectional drawing which shows the structure of the light source module by Embodiment 4 of this invention. It is a circuit block diagram which shows an example of the drive circuit of the gas discharge apparatus of this invention.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. In order to simplify the description, the same components are denoted by the same reference numerals. In the following embodiments, the discharge electrodes constituting the electrode pair are referred to as “long electrodes” for convenience, but the lengths are not limited. The “touch contact type” means a structure in which the electrode is connected to the arc tube by a detachable simple contact without physical adhesion, but excluding a detachable adhesive structure or a clamp structure. Absent.

(Embodiment 1)
1A and 1B are a longitudinal sectional view and a transverse sectional view showing a basic configuration of a gas discharge light emitting device according to the present invention as a first embodiment. The gas discharge light emitting device of the present invention comprises an arc tube assembly 10 and an electrode assembly 20 each having an independent part configuration.

  The arc tube assembly 10 mainly includes an arc tube 12 including a glass tube 11 in which a mixed gas of neon (Ne) and xenon (Xe) is sealed and hermetically sealed at both ends, and the arc tube 12 is a glass tube 11. And an ultraviolet light emitting phosphor layer 13 formed on the bottom inner surface of the back side 11a. As a feature of the present invention, the arc tube assembly 10 is mainly an elongated glass tube having no electrode inside or outside the tube.

The glass capillary 11 is a transparent borosilicate glass pipe base material mainly composed of silicon oxide (SiO ₂ ) and boron oxide (B ₂ O ₃ ), and is a capillary having an outer diameter of 5 mm or less and a wall thickness of 500 μm or less. It is formed by redrawing (drawing).

  The cross section of the glass thin tube 11 is preferably a flat oval shape having flat surfaces facing each other as shown in FIG. 1 (b), but may be a circle, rectangle, rectangle, trapezoid or the like. When the ultraviolet light emitting phosphor layer 13 is formed on the inner surface of the glass thin tube 11 to constitute a gas discharge device for an ultraviolet light source, the thickness of the front side 11b serving as the light emitting surface of the glass thin tube 11 is reduced to 300 μm or less. This is important in terms of transmittance.

  Even in the case of borosilicate glass, by setting the thickness to 300 μm or less, it is possible to obtain a transmittance of 90% or more with respect to ultraviolet rays in the UV-B wavelength band. In this case, the mechanical strength may be increased by increasing the thickness of the back side 11a relative to the thickness of the front side 11b of the glass tube 11. The thin glass tube 1 having an asymmetric thickness of the facing surface can be realized by controlling the heat treatment process during shaping of the glass base material.

When a gadolinium activated phosphor (LaMgAl11O19: Gd) is used as an example of the ultraviolet light emitting phosphor layer 13, ultraviolet light emission of 311 nm which is the wavelength range of the UV-B band can be obtained. Further, if a praseodymium-activated phosphor (YBO ₃ : Pr or Y ₂ SiO ₅ : Pr) is used, UV emission of 263 nm or 270 nm in the wavelength range of the UV-C band can be obtained.

  For the formation of the phosphor layer 13 on the inner wall surface of the glass capillary 11, a well-known sedimentation method or solution passing method can be used. Further, when a small amount of a visible phosphor, for example, a red phosphor, is mixed with the ultraviolet light emitting phosphor layer 13, it is possible to widen the emission spectrum width or to confirm the invisible ultraviolet spectrum light emission by the red visible light emitting component. It becomes.

  On the other hand, in the configuration of FIG. 1, an electrode assembly 20 that constitutes a part independent of the arc tube assembly 10 has a gap dimension Dg on an insulating substrate 21 made of polyimide resin such as Kapton tape (trade name). It consists of a pair of elongate long electrodes 23 and 24 arranged with a gap 22 therebetween. For convenience of explanation, one long electrode 23 is referred to as an X electrode, and the other long electrode 24 is referred to as a Y electrode.

  In a state where the arc tube assembly 10 is placed on the electrode assembly 20, adjacent adjacent ends of the pair of long electrodes constitute the trigger electrode portions 23 a and 24 a, and the gap dimension Dg of the gap portion 22 is set. A trigger discharge portion 15 is formed in the gas space in the corresponding arc tube 12. Further, the extension portions extending in the direction away from the trigger electrode portions 23a and 24a on both sides constitute main electrode portions 23b and 24b having an effective length EL, and the corresponding gas space of the main electrode portions 23b and 24b is the main gas discharge portion 16. It becomes.

  The X electrode 23 and the Y electrode 24 may be a metal conductor foil such as a copper foil or an aluminum foil attached on a base film such as a resin, or may be constituted by a conductive film directly formed by a vapor deposition method or a printing method. Good. In Embodiment 1 shown in FIG. 1, the long electrode pair is provided on the front side of the insulating substrate 21, but an electrode may be arranged on the back side of the substrate. A configuration in which an insulating substrate is interposed between the arc tube 12 and the X and Y electrode pairs 23 and 24 will be described later in Embodiment 2 with reference to FIG.

  When the arc tube assembly 10 is detachably mounted on the electrode assembly 20, the gas discharge light emitting device of the present invention is completed. The elongated arc tube 12 can be operated only by being placed in a direction crossing (stranding) the gap 22 along the X and Y electrodes 23 and 24 in the electrode assembly 20.

  Strict alignment between the two assemblies is not necessary, but in order to keep the mounting state stable, an adhesive means or a mechanical clamping means (not shown) is appropriately provided. A range obtained by combining the gap dimension Dg and the effective length EL × 2 of the X and Y electrodes 23 and 24 is an effective light emitting region.

  FIG. 2 is a schematic diagram for explaining the discharge model of the gas discharge light-emitting device shown in FIG. 1 in time series. Between the pair of X and Y electrodes 23 and 24, as shown in FIG. 2B, with one X electrode 23 grounded, a sine wave AC power supply AC is applied to the other Y electrode 24. Connect and apply an AC voltage with a sinusoidal waveform as shown in FIG.

  When the voltage v1 in the rising process of the sine wave voltage exceeds the discharge start voltage Vd between the trigger electrode portions 23a and 24a at the timing t1, the trigger discharge portion 15 generates a discharge. A large amount of space charge is supplied to the nearby gas space by this trigger discharge, a so-called seed-fire effect occurs, and discharge increases toward the main electrode portions 23b and 24b of the X and Y electrodes 23 and 24 as the voltage of the sine wave increases. It expands and shifts to so-called long-distance discharge.

  At the same time, charges (electrons (-) and cations (+)) of opposite polarity to the applied voltage are accumulated as wall charges on the inner wall surface of the arc tube 12 corresponding to the trigger electrodes 23a and 24a that first generated the trigger discharge. Then, the electric field due to the wall charges cancels the electric field of the applied voltage, and the discharge at the trigger discharge portion 15 is stopped.

  2 (b), (c), (d), and (e) schematically show the discharge and wall charge accumulation states corresponding to the timings t1 to t4 of the applied sine wave voltage in FIG. 2 (a). FIGS. (F), (g), (h), and (i) schematically show the discharge and wall charge accumulation states corresponding to the timings t5 to t8 after the polarity inversion.

  From this discharge model, the discharge generated in the trigger discharge portion 15 corresponding to the gap 22 between the trigger electrode portions 23a and 24a at the timing t1 is accompanied by the accumulation of wall charges in the rising process of the applied voltage following the timings t2 and t3. It can be understood that the main discharge portions 16 are expanded along the extending direction of the main electrode portions 23b and 24b.

  Further, at the timing t4 of the voltage decreasing process after the applied sine wave voltage reaches one peak value, the wall charge is accumulated as shown in FIG. 2E and the discharge is stopped. Thereafter, at the timing t5 when the polarity of the applied voltage is reversed, the electric field of the accumulated wall charges is added to the electric field in the process of increasing the opposite polarity of the applied sine wave voltage.

  As a result, the effective voltage applied to the trigger discharge portion 5 of the trigger electrode portions 23a and 24a exceeds the discharge start voltage, and trigger discharge occurs again as shown in FIG. Thereafter, the discharge expands toward the main discharge portion 16 as shown in FIGS. 2G and 2H, respectively, at timings t6 and t7, accompanied by generation of wall charges of opposite polarity. Then, at timing t8 when the discharge expands to the end of the arc tube 12, the wall charge state as shown in FIG. Thereafter, this operation is repeated.

  In order to generate a composite discharge using the rising process of the applied voltage, a voltage having a sawtooth waveform (ramp waveform) or a slowly rising pulse voltage can be used in addition to the above sine wave voltage. However, it is desirable to use a sine wave voltage in terms of ease of waveform generation. The brightness can be adjusted by changing the frequency of the sine wave voltage or the inclination angle of the sawtooth waveform voltage. Alternatively, the irradiation intensity can be adjusted by intermittently applying a sinusoidal driving voltage and adjusting the application time width and interval.

  With the application of the sine wave voltage, such a composite discharge is alternately repeated between the pair of X and Y electrodes 23 and 24, and each time, cathode glow light emission and positive column light emission are generated along the discharge path. . When a gas in which neon (Ne) is mixed with several percent xenon (Xe) is used as a discharge gas, neon orange light emission and vacuum ultraviolet rays (VUV) having wavelengths of 143 nm and 173 nm are obtained as discharge light.

  Therefore, if the mixing ratio of Ne and Xe is appropriately adjusted and light emission of gas discharge is used as it is, a neon color light emitting device or an ultraviolet light emitting device can be obtained without providing the phosphor layer 13 as described above. .

  In the case of the gas discharge light-emitting device of Embodiment 1 shown in FIG. 1, the glass thin tube 11 has a diameter of 5 mm to 0.5 mm. For example, the long diameter dimension is 2 mm, the short diameter dimension is 1 mm, and the wall thickness is 100 μm. It can be a thin tube having a flat elliptical cross section.

  Here, the gap dimension Dg of the gap portion 22 between the pair of X and Y electrodes 23 and 24 in the electrode assembly 20 is an important factor for determining the trigger discharge start voltage, and 5 mm or less is practical. For example, it can be 3 mm. In this case, the discharge start voltage Vd of the trigger discharge section 5 is about 900V.

  On the other hand, the spread of discharge in the extending direction from the trigger electrode portions 23a, 24a of the paired X, Y electrodes 23, 24 to both sides varies depending on the peak voltage Vp of the applied sine wave voltage. If the peak voltage Vp is too high, there is a risk of causing damage to the trigger discharge portion 15. That is, the gap dimension Dg of the trigger electrode portions 23a and 24a is normally set in a range of about 0.1 mm to 2 cm, but the peak voltage Vp of the sine wave depends on the effective light emitting region length (2EL + Dg) of the light emitting capillary 1. Will be different.

  Therefore, the length EL of the X and Y electrodes 23 and 24 is set to be not less than 3 times, preferably about 10 times the gap dimension Dg between the trigger electrode portions 23a and 24a. When the total length of the effective light emitting region length is 50 mm, the trigger electrode gap length Dg can be set to 3 mm, and the length EL of both main electrode portions can be set to 23.5 mm.

  As a result, the arc tube assembly 10 corresponding to the electrode assembly 20 provided with only one pair of long electrodes 23 and 24 as shown in FIG. 1 has a length of about 5 to 10 cm as a whole. As will be described later, by adopting a configuration in which a plurality of pairs of X and Y electrodes 23 and 24 are alternately arranged in series, a gas discharge light emitting device having a longer luminous tube can be configured.

  The frequency of the sine wave voltage is set to several tens of kHz, for example, 40 kHz from the relationship between the interelectrode capacitance and the impedance. The peak voltage Vp is set to a value higher than 1000 V or higher depending on the discharge start voltage Vd of the trigger discharge section 15, and the upper limit thereof is the spread length of the discharge on the long electrode and the trigger discharge section. It is desirable to decide in consideration of 5 damage prevention. Note that since the load is capacitive in the actual drive waveform, the same operation can be performed with a pulse waveform that takes into account the occurrence of rise and fall times.

  In addition, the gas discharge device of the present invention adopts a discharge type that expands while stopping discharge along a long electrode by utilizing the accumulation of wall charges, so that the peak current during driving can be kept low. In addition, it consumes much less power than LEDs and excimer discharge lamps.

  In order to drive the gas discharge device according to the first embodiment, a commercially available 5 W product including an inverter circuit that converts a DC voltage of 10 V into a sine wave voltage of 42 KHz and a small transformer that boosts the sine wave voltage to a peak voltage of 1000 V. A small power supply circuit (for example, HIU-465 type manufactured by Harrison Electric) could be suitably used.

Incidentally, in the gas discharge light-emitting device according to the first embodiment, the ultraviolet light-emitting phosphor layer 13 is mainly composed of an arc tube having a major axis size of 2 mm and an effective luminous area of 50 mm using the above-described gadolinium activated phosphor. By applying a sine wave voltage having a frequency of 40 kHz and a P-P voltage of 3000 V between 23 and 24, a combined discharge of a trigger discharge between the electrode pair adjacent ends and a long distance discharge along the long electrode is repeated, Accordingly, ultraviolet emission having a peak at a wavelength of 311 nm could be obtained with an emission intensity of 5 mW / cm ² , and the luminous efficiency at that time was 24% W / W.

(Embodiment 2)
3A and 3B are a plan view and a cross-sectional view showing a schematic configuration of a planar light source as Embodiment 2 of the present invention.
The arc tube assembly 110 is composed of an arc tube 112 made of a plurality of glass capillaries (six in the figure), and each arc tube 112 is placed on the electrode assembly 120 in parallel in the form of a touch contact. A gas discharge light emitting device 100 having a planar configuration is provided.

  Each arc tube 112 in the arc tube assembly 110 has substantially the same configuration as the arc tube 12 of the first embodiment. On the other hand, the electrode assembly 120 includes discharge electrode pairs 123 (X) and 124 (Y) on the back surface, that is, the lower surface of the film-like insulating substrate 121 as shown in FIG. The paired discharge electrodes 123 and 124 have a sheet-like solid pattern common to the plurality of arc tubes 112 to be placed, and a gap of a dimension Dg is provided between the adjacent end portions of the discharge electrodes 123 and 124. ing. A polyimide resin film with a thickness of about 25 to 50 μm is suitable for the insulating substrate 121, and an aluminum foil with a thickness of about 10 μm is suitable for the electrode material.

  Thus, the arc tube 112 made of a thin glass tube is placed on the insulating substrate 121 of the electrode assembly 120 side by side in a direction crossing the gap of the dimension Dg between the electrode adjacent end portions, so that a planar light source having a predetermined area can be obtained. Complete.

  In this state, the common electrode pairs 123 and 124 have the same long electrode pair arrangement relationship as in the first embodiment with respect to the longitudinal direction of each arc tube 112, and can be driven in common on the same principle as a planar light source. . Further, by providing an appropriate space SP between the adjacent arc tubes 112, the light emitting device 100 has flexibility in the arrangement direction of the arc tubes 112.

  Furthermore, a major feature of Embodiment 2 is that a planar light source is configured by arranging a plurality of arc tubes. Therefore, the juxtaposed arc tubes do not necessarily have to have phosphors having the same emission wavelength. For example, by using two kinds of phosphors as described above, two kinds of light-emitting tubes emitting ultraviolet light having a light emission wavelength of 311 nm and ultraviolet light having a wavelength of 263 nm are formed, and both are arranged at a predetermined number ratio, so that 311 nm and 263 nm. An ultraviolet light emitting device that emits ultraviolet light at an arbitrary energy ratio can be produced.

  Such a multi-wavelength composite planar light source can be configured in various combinations according to the application field, such as a combination of ultraviolet light and visible light. In addition, it is possible to easily design the distribution of ultraviolet emission energy by using several arc tubes with different emission spectra, or by appropriately combining arc tubes with different emission energies, and further improve their uniformity. Can be made.

  For light-emitting tubes having different emission wavelengths, the light-emitting wavelength is selectively driven by extending the electrode pair pattern of the corresponding electrode assembly in the longitudinal direction of the light-emitting tube so that it is appropriately shared on the insulating substrate. Can be made. Alternatively, long electrode pairs for each arc tube can be derived individually or as a plurality of sets, and thinning driving or area selection driving can be performed.

  By the way, in the configuration in which the X and Y electrode pairs 23 and 24 are in direct contact with the bottom surface of the glass thin tube 11 as in the first embodiment, unnecessary air discharge occurs along the tube surface at the edge of the contact surface during driving. A phenomenon may be observed.

  That is, when driving by applying one of the long electrode pairs to the other and applying a sine wave voltage to the other, the arc tube becomes substantially conductive by the plasma over the entire length when the applied voltage reaches the peak. The potential corresponds to the peak voltage, and it is considered that an unexpected air discharge along the outer wall surface of the tube occurs at the edge of the opposing electrode.

  Such creeping discharge is accompanied by generation of harmful ozone, consumes invalid power, causes damage to the electrode assembly and the arc tube, and is not preferable for safety.

  In this regard, in the configuration in which the thin film-like insulating substrate 121 of the electrode assembly 120 is interposed between the electrode pairs 123 and 124 and the glass thin tube 111 as in the second embodiment, it is along the lower side edge of each glass thin tube. Unnecessary air discharge can be effectively prevented. Further, since the electrode pairs 123 and 124 are not exposed on the surface of the electrode assembly 120, there is no risk of electric shock when the arc tube is replaced.

(Embodiment 3)
4A and 4B are a plan view and a main part sectional view showing a configuration of a large planar light source as Embodiment 3 according to the present invention. In this embodiment, an arc tube assembly 210 having a plurality of arc tube units each made of a long glass capillary is touched on an electrode assembly 220 on which a plurality of pairs of discharge electrodes are arranged. A gas discharge light-emitting device having a configuration of being mounted in a contact form is provided. In addition, in the top view shown to Fig.4 (a) and the sectional drawing shown to the same (b), (c), the dimension of each member is drawn by the magnitude | size which does not respond | correspond for convenience of illustration.

  As shown in the cross-sectional view of FIG. 4 (b), the arc tube assembly 210 is configured with a plurality of arc tube units 218 in which the arc tube 212 is illustratively a group of three. Each arc tube unit 218 is arranged in parallel on a thin insulating sheet 219 such as Kapton tape (trade name) as a substrate. In this state, no electrode is attached to the arc tube assembly 210 anywhere.

  On the other hand, as shown in the longitudinal sectional view of FIG. 4 (c), the electrode assembly 220 insulates the two pairs of X and Y electrodes 231 and 232 with a non-discharge gap shown by a broken line (FIG. 4a). The structure is arranged on the upper surface of the substrate 221. The total arrangement width of the two pairs of electrodes corresponds to the effective light emitting area length corresponding to the length of each arc tube 212 of the arc tube assembly 210.

  Each of the X and Y electrode pairs 231 and 232 includes X electrode pieces 31X, 32X and Y electrodes made by pasting aluminum foil or copper metal foil conductors cut into strips (segments) on the insulating substrate 221. It consists of pieces 31Y and 32Y, and has a length that crosses the arc tubes 212 of all the arc tube units in common.

  As in the first embodiment, the X electrode pieces 31X, 32X, and Y electrode pieces 31Y and 32Y of each electrode pair are elongated in the direction crossing the arc tube 212, but the width is the tube diameter for each arc tube 212. It functions as a long electrode pair along the longitudinal direction at a position where it intersects with each arc tube.

  In the above configuration, the arc tube assembly 210 is composed of the arc tube unit 218 in which a plurality of arc tubes 212 are grouped, in this case, three each, but of course, all the arc tubes are mounted on a common insulating sheet 219. The arc tube assembly may be configured by being affixed to. However, as shown in FIG. 4 (b), the unit configuration in which several or several tens of arc tubes are grouped makes it easy to assemble, repair and replace, and to easily change the light emitting surface size. It becomes possible to cope with.

  Each arc tube unit 218 constituting the arc tube assembly 210 is detachably mounted in a state where the lower surface of the insulating sheet 219 serving as the support is in contact with the XY electrode pairs 231 and 232 of the electrode assembly 220. However, this does not exclude the use of adhesive means and mechanical clamping means for maintaining the mounted state. In the configuration of FIG. 4, the electrode assembly 210 has the electrode pairs 231 and 232 arranged on the front side of the insulating substrate 221, but the electrode pairs may be provided on the back side of the insulating substrate. In this case, two insulating sheets for supporting the arc tube assembly and for supporting the electrode assembly are interposed between the arc tube 212 and the electrode pair, both of which are about 50 μm or less. Since it is a thin film, there is no problem in applying the alternating drive voltage.

  As shown in FIG. 4A, in the gas discharge light emitting device of the third embodiment, a DC power source such as a battery BT is used as a common power source, and two X and Y electrode pairs 231 and 232 are respectively provided in separate drive circuits 241. 242 is connected to drive. Each drive circuit includes an inverter circuit and a booster circuit, which will be described later with reference to FIG. 6, and applies a sine wave drive voltage to one of the Y electrode pieces 31Y and 32Y that form a pair. The other X electrode pieces 31X and 32X of each electrode pair are held at the ground potential.

  Of course, the Y electrode pieces 31Y and 32Y of the two X and Y electrode pairs 231 and 232 can be commonly connected and driven by a single drive circuit. However, by adopting the divided drive configuration as shown in the figure, it is possible to correspond to a light emitting device of any light emitting surface size by combining a required number of standardized small and inexpensive driving circuits, and in terms of standardization of parts It is advantageous.

  In addition, when a long arc tube is driven by arranging a plurality of electrode pairs, a discharge dead space is formed between adjacent electrode pairs, and luminance reduction is inevitable in this portion. In this regard, driving each electrode pair by making the phases of the sinusoidal drive voltages applied from the individual drive circuits different from each other is effective in making the luminance distribution in the tube axis direction of the arc tube uniform. Of course, it is also possible to make the luminance distribution of the peripheral part or the non-discharge part uniform by using optical means such as a reflecting mirror or a diffusing plate.

  Furthermore, in order to make the luminance distribution uniform, the X electrode pieces 31X, 32X and the Y electrode pieces 31Y, 32Y are alternately arranged in parallel at equal intervals, and the combination of adjacent electrode pieces is alternately turned up and down at a predetermined cycle. It is also effective to drive so that adjacent electrode pieces are in phase with each other and a driving voltage is applied between the pairs of electrode pieces. According to such a driving method, discharge without a gap over the entire length of the long arc tube can be alternately performed corresponding to all of the odd-numbered gaps and even-numbered gaps of the XY electrode pieces.

  As an example, an arc tube unit 218 having a width of 2 cm was prepared by arranging ten arc tubes 212 having a major axis dimension of 2 mm and an effective discharge area length of 20 cm on a common insulating sheet, and 10 units were prepared. On the other hand, two pairs of segmented XY electrode pieces 31X, 32X and 31Y, 32Y each having a length of 20 cm with a pair of electrode arrangement width of 10 cm were arranged on a common insulating substrate 221 to produce an electrode assembly 220.

  A planar light source having an effective light emitting surface of 20 × 20 cm is obtained by superimposing ten arc tube units 218 on such an electrode assembly 220 in a direction crossing the gap between the electrode pieces with which each arc tube is paired. Could be configured.

  The large planar light source according to the third embodiment can be efficiently driven by the split driving method shown in FIG. Each drive circuit has the configuration shown in FIG.

(Embodiment 4)
FIG. 5 is a schematic cross-sectional view of a light source module (gas discharge light emitting device) 300 integrated with a drive circuit as the fourth embodiment. In this light source module 300, an electrode assembly 320 is placed on a printed circuit board 332 constituting a drive circuit assembly 331 via a shock absorbing layer 333, and an arc tube assembly 310 including an arc tube 312 is stacked thereon. And is housed in an outer frame or case 334 as a whole. As described in the third embodiment, the arc tube assembly 310 may have a unit configuration in which a plurality or all of the arc tubes are arranged on a support substrate.

  The electrode assembly 320 includes an insulating substrate 321 and an X electrode 323 and a Y electrode 324 provided on the lower surface thereof. The outer frame or case 334 is provided with clamping means 335 for holding the three assemblies in a predetermined positional relationship. Further, a light-transmissive protective plate 336 is provided on the front surface of the light source module 300 so as to cover the upper surface of the arc tube 312.

    As the shock absorbing layer 333, a flexible insulating material having high thermal conductivity and shock absorbing properties, such as a silicon compound or a silicon sheet, is preferable. As the protective plate 336, an acrylic or fluorine resin film or thin plate having a good ultraviolet transmittance is used. A component 337 of a drive circuit assembly 331 described later is mounted on the printed board 332.

  A pair of X power supply terminals 343 and Y power supply terminals 344 that are in contact with one X electrode 323 and the other Y electrode 324 of the electrode assembly 320 are provided on the left and right sides of the upper surface of the printed board 332. The contacts between the X and Y electrodes 323 and 324 and the corresponding X and Y feed terminals 343 and 344 do not require a fixed connection as in a DC circuit.

  Since the drive voltage is an alternating voltage of several tens of kilohertz, the drive voltage is supplied from the drive circuit assembly 331 to the arc tube assembly 310 through the electrode assembly 120 without any loss in a touch contact form in which both are overlapped. The drive circuit assembly 331, the electrode assembly 320, and the arc tube assembly 310 are all assembled in a touch contact form, and are not fixed by soldering among them. Accordingly, the arc tube assembly 310 can be easily detached from the light source module 300.

  The drive circuit assembly 331 generates a sine wave drive voltage to drive the arc tube assembly 310. One of the X power supply terminals 343 is grounded and brought into contact with the X electrode 323, and a sine wave drive voltage is supplied from the other Y power supply terminal 344 to the Y electrode 324, whereby discharge light emission of the operation principle as described above can be performed. Can be obtained.

  An insulating substrate 321 is provided on the surface of the electrode assembly 320, and the X and Y electrodes 323 and 324 are not exposed. Therefore, there is no danger of electric shock by directly touching the electrode when adjusting or replacing the arc tube.

  Incidentally, by using an arc tube assembly having a configuration in which 30 gas discharge luminous tubes 10 having a length of 2 cm and a minor axis diameter of 1 mm and having a flat elliptical cross-sectional shape and a length of 10 cm in an effective discharge region are arranged at intervals of 1 mm. The planar light source module 300 having a light emission area of 90 square cm can be configured.

  In addition, the diameter of the glass thin tube 11 serving as the arc tube is 5 mm at the maximum, and even if the shock absorbing layer 333, the printed circuit board 332 on which the circuit component 337 is mounted, and the front protective plate 336 are combined, the thickness of the entire light source module 300 is increased. The length is about several centimeters.

  That is, to drive the light source module 300, a sine wave drive circuit having a peak-to-peak voltage of several thousand volts and a frequency of several tens of kHz is required. There is an advantage that it can be driven by an inverter power supply.

  An inverter power supply circuit of this scale can be contained in a height of 1 cm or less including a step-up transformer, and therefore the size of the case 334 is about 9 × 10 cm square with a thickness of about 1 cm.

  FIG. 6 is a circuit diagram showing an example of the circuit configuration of the drive circuit assembly 331. As shown in FIG. A DC power source (battery) BT capable of setting a voltage in the range of DC6-18V is connected to the inverter circuit section INV via an input plug PL1.

  The inverter circuit unit INV includes transistors Q1 and Q2, a coil L1, resistors R1 and R2, and a capacitor C1. The alternating output of the inverter circuit section INV is taken out from the secondary winding of the step-up transformer TF to the output plug PL2. By appropriately setting the circuit constants of each circuit component, a sinusoidal alternating high voltage is obtained at the output plug PL2, and is applied between the X electrode 323 and the Y electrode 324 located opposite the arc tube 312.

  The frequency of the sine wave voltage can be adjusted in the range of 10 kHz to 80 kHz by changing the capacitance of the capacitor C1, and the peak value of the sine wave output voltage can be adjusted in the range of 1000V to 8000V by changing the voltage of the battery BT. Can be adjusted. Although not shown, a gate circuit is provided between the inverter circuit INV and the step-up transformer TF so that the sine wave drive voltage supplied to the arc tube 312 is intermittently applied at an arbitrary duty cycle. Also good. The intensity of the light emission output can be stably adjusted by adjusting the application time width and the duty ratio.

  In the drive circuit shown in FIG. 6, it is noted that there is no current limiting capacitor normally provided in the output line of the step-up transformer TF. One output line of the step-up transformer keeps the X electrode 323 of the electrode assembly 320 to the ground potential through the contact contact with the X power supply terminal 343, while the sine wave drive voltage from the other output line is connected to the Y power supply terminal 344. To the Y electrode 324 through the contact contacts. Since the arc tube assembly 310 is a complete capacitive load with respect to the drive circuit assembly 331, unnecessary power loss can be eliminated by omitting the output capacitor.

  Note that a circuit component 337 such as a coil, a capacitor, and a transformer constituting the drive circuit assembly 331 is mounted on the printed circuit board 332. The printed circuit board 332 is housed and fixed in the case 334 with the mounted components facing downward, and the electrode assembly 320 and the arc tube assembly 110 are sequentially stacked on the printed circuit board 332.

  Further, the battery BT serving as a power source may be accommodated by providing a battery accommodating portion in the case 334, or may be connected to an external power source by pulling a power connection line from the printed board 332. Moreover, you may use DC power supply which converts a commercial voltage other than a battery.

  As is apparent from the above description, the present invention has an arc tube assembly mainly composed of an arc tube having no electrode itself and an electrode assembly that applies a driving voltage to the arc tube as independent parts. The gas discharge light-emitting device is configured by combining them in a touch contact form. This configuration is possible for the first time by adopting a special AC composite discharge format between the pair of long electrodes described with reference to FIG. 2, and is different in principle from a conventional discharge tube. .

  In the gas discharge light emitting device of the present invention, it is possible to easily cope with breakage or deterioration of the arc tube at a low cost by preparing a simple arc tube having no electrode as a component. Further, by using the present invention, it is possible to efficiently obtain planar ultraviolet light emission having a higher light emission intensity per area than that of an LED or the like.

10: arc tube assembly 11: glass tube 12: arc tube 13: phosphor layer 20: electrode assembly 23: X electrode 24: Y electrode 21: insulating substrate

Claims (15)

An arc tube assembly comprising at least one arc tube made of a glass tube filled with discharge gas, and at least a pair of discharge electrodes extending on both sides of the gap constituting the discharge gap on the back side of the insulating substrate are arranged. It consists electrode assembly, a gas discharge light emitting device in which the arc tube the arc tube assembly to the surface side, characterized in that mounted detachably in a direction transverse to the gap of the insulating substrate.   The arc tube assembly has a configuration in which a plurality of arc tubes are arranged in parallel, and the electrode assembly has a common discharge electrode pair for the plurality of arc tubes. The gas discharge light-emitting device according to claim 1.   The gas discharge light-emitting device according to claim 1, wherein the arc tube assembly has a configuration in which a plurality of arc tubes having different emission wavelengths are arranged in parallel. And characterized in that said arc tube assembly is have a structure arrayed in parallel a plurality of light-emitting tube on the insulating film, the lower surface of the insulating film is placed detachably on an insulating substrate of the electrode assembly The gas discharge light-emitting device according to any one of claims 1 to 3. An arc tube assembly comprising at least one light emitting tube made of glass capillary where the discharge gas is enclosed, consisting electrode assembly and arranged at least one pair of discharge electrodes on the surface side of the first insulating substrate, the light emitting A gas discharge light emitting device characterized in that a tube assembly has a second insulating substrate, and the second insulating substrate supports the arc tube and is detachably mounted on the electrode assembly. . In a state where the arc tube assembly is placed on the electrode assembly, the electrodes constituting the discharge electrode pair are disposed at the proximal end with a gap at a proximal end portion serving as a discharge gap in the longitudinal direction of the arc tube. The gas discharge light-emitting device according to any one of claims 1 to 5 , wherein the gas discharge light-emitting device has a pattern extending on both sides at least three times the gap length. The discharge electrode pairs of the electrode assembly is provided in pairs in series in the longitudinal direction of the bulb, and, of claims 1 to 6, characterized in that connected to independent drive circuit for each one or more pairs The gas discharge light-emitting device according to any one of the above. The thickness of the front side, which is the light emitting surface of the glass tube constituting the arc tube, is 300 μm or less, and an ultraviolet light emitting phosphor layer is provided on the inner surface on the back side facing the electrode assembly facing the front side. gas discharge light emitting device according to any one of claim 1 to 7, characterized in that to become to. An arc tube assembly including at least one arc tube made of a glass thin tube filled with a discharge gas, and an electrode in which at least one pair of discharge electrodes extending on both sides of the gap constituting the discharge gap is disposed on one surface of the insulating substrate. The glass thin tube comprising the assembly and constituting the arc tube has a flat elliptical cross-sectional shape with a major axis dimension of 5 mm or less with the thickness of one flat surface on the front side being 300 μm or less, and the back surface A fluorescent light emitting phosphor layer is provided on the inner side of the other flat surface, and the arc tube assembly is arranged such that the flat surface on the back side of the arc tube faces the electrode assembly. A gas discharge light-emitting device, wherein the gas discharge light-emitting device is detachably disposed on the electrode assembly in a direction in which the longitudinal direction of the electrode crosses the gap between the electrode pairs . A touch contact configuration further comprising a drive circuit assembly disposed under the electrode assembly, wherein electrical connections among the arc tube assembly, the electrode assembly, and the drive circuit assembly are detachable. The gas discharge light-emitting device according to any one of claims 1 , 5, and 9 , wherein: A drive circuit assembly including a printed circuit board on which circuit components are mounted, and an arc tube assembly in which a plurality of arc tubes made of glass capillaries each including a phosphor layer and filled with a discharge gas are juxtaposed. A light source module having an electrode assembly including at least one pair of discharge electrodes sandwiched therebetween, wherein the arc tube assembly and the electrode assembly are configured such that the discharge electrode pair is connected to the arc tube. A gas discharge light emitting device having a touch contact configuration that is detachably superimposed so as to face each other with a long electrode extending on both sides from a gap at a proximal end constituting a discharge gap along a longitudinal direction thereof. The electrode assembly includes a plurality of electrode pairs common to the plurality of arc tubes, and the electrode pairs are divided into a plurality of electrode sets each including at least one pair of electrodes. The gas discharge light-emitting device according to claim 11 , wherein each set is connected to an individual drive circuit. The at least one pair of discharge electrodes of the electrode assembly is made of a conductive foil having a length extending to both sides at least three times the gap with a gap of 0.1 to 20 mm, and the arc tube of the arc tube assembly There the gas discharge light emitting device according to any one of claim 1 to 12, characterized in that is placed across the gap. An arc tube assembly including at least one arc tube made of a glass thin tube with a discharge gas sealed therein, and a gap between which one end of the insulating substrate forms a discharge gap on one side of the insulating substrate is at least three times the gap. An electrode assembly in which a pair of discharge electrodes extending on both sides with a width is arranged, and the arc tube of the arc tube assembly spans the gap between adjacent end portions of the discharge electrode pair over the entire length of the effective light emitting region. A gas discharge light-emitting device, wherein the gas discharge light-emitting device is detachably mounted on the electrode assembly so as to face the pair of discharge electrodes. 15. The drive circuit according to claim 1, further comprising a drive circuit that intermittently applies an alternating drive voltage at a predetermined duty ratio to at least one pair of discharge electrodes of the electrode assembly. The gas discharge light-emitting device according to any one of the above.

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