JPH11167901A - Rare gas discharge lamp and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rare gas discharge lamp capable of easily improving starting characteristics in a dark state, by a comparatively simple structure. SOLUTION: A discharge lamp is equipped with an envelope 1 having a luminous layer 2A comprising phosphor on its inner surface and a pair of strip- shaped external electrodes 5, 6 comprising metallic members disposed to be spaced apart from each other over a total length and the peripheral surface of the envelope 1 so as to disperse and contain an oxide of cesium. It is desirable that the oxide of cesium be dispersed and contained in the luminous layer 2A in a range of 0.2 to 5.0 wt.% with respect to phosphor weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rare gas discharge lamp and a method for manufacturing the same, and more particularly, to a method of manufacturing a rare gas discharge lamp having an inner surface provided with a glass bulb.
In a rare gas discharge lamp in which a light emitting layer having a char portion is formed and a pair of strip-shaped external electrodes are arranged on the outer peripheral surface, the improvement of starting characteristics in an environment where external light irradiated on the rare gas discharge lamp is scarce is provided. .

[0002]

2. Description of the Related Art The present applicant has previously proposed a rare gas discharge lamp shown in FIGS. In FIG. 1, reference numeral 1 denotes a straight tubular envelope which is hermetically sealed by a glass bulb, for example, and one or two or more kinds of fluorescent materials such as a rare earth phosphor and a halophosphate phosphor are provided on the inner surface thereof. A light emitting layer 2 including a body is formed. In particular, the light emitting layer 2 is formed with an aperture 2a having a predetermined opening angle over substantially the entire length. The sealing structure of the envelope 1 is configured by sealing a disk-shaped sealing glass plate to an end of a glass bulb. It can also be configured. In addition, a rare gas such as xenon (Xe), krypton (Kr), neon (Ne), helium (He) or the like containing no metal vapor such as mercury is used in the inner space of the envelope 1 alone or as a mixture. Although a predetermined amount is filled, it is desirable to fill a rare gas containing xenon as a main component.

[0003] A sheet structure 3 is wound around the outer peripheral surface of the envelope 1 so as to be in close contact therewith. This sheet structure 3
For example, an insulative translucent sheet 4 having a length substantially equal to the entire length of the envelope 1 and one surface of the translucent sheet 4 are spaced apart from each other by a predetermined distance. A pair of strip-shaped external electrodes 5 and 6 made of a bonded opaque metal member;
Terminals 51, 6 derived from the ends of the external electrodes 5, 6
1 and an adhesive layer 9 provided on one surface of the translucent sheet 4 and having an adhesive or adhesive function.

In particular, when the sheet structure 3 is mounted on the envelope 1, a first opening 7 is provided between the one ends 5a and 6a of the external electrodes 5 and 6, and the first opening 7 is provided between the external electrodes 5 and 6. Second openings 8 are formed between the ends 5b and 6b, respectively, and light from the light emitting layer 2 is mainly emitted from the aperture 2a to the outside through the first openings 7. Then, in the second opening 8, one end 4a of the translucent sheet 4 is bonded to the other end 4b while being superposed. In this sheet structure 3, the translucent sheet 4 is preferably made of, for example, polyethylene terephthalate (PET) resin.
Other resins such as polyester resins can also be used. The external electrodes 5 and 6 are preferably made of, for example, aluminum foil. However, other metal members such as nickel and silver can be used as long as the metal members are excellent in conductivity and are opaque. Further, a silicone-based adhesive is suitable for the adhesive layer 9, but other adhesives such as an acrylic adhesive can also be used.

The rare gas discharge lamp L is manufactured, for example, as follows. First, for example, a phosphor coating solution containing a phosphor having an emission spectrum in each of a blue region, a green region, and a red region is applied to the inner surface of the envelope 1 made of a glass bulb, dried, and fired, so that the light emitting layer 2 is formed. It is formed.
Next, by using a scraper (not shown), a part of the light emitting layer 2 is forcibly peeled off and removed at a predetermined opening angle to form an aperture portion 2a. Next, the envelope 1 is formed in a sealed state, and a predetermined amount of a rare gas such as xenon is sealed in the internal space.

Next, as shown in FIGS. 12 and 13, a pair of external electrodes 5 and 6 are spaced apart from each other at a predetermined portion of the light-transmitting sheet 4, and the end portions of the external electrodes 5 and 6 are arranged. To terminal 5
The sheet structure 3 is formed by drawing out the adhesive layers 9 from the light-transmitting sheet 4 and the external electrodes 5 and 6.
Next, as shown in FIG. 14, the sheet structure 3 is placed on, for example, an assembly stage 10 in an expanded state. Subsequently, the envelope 1 is connected to one end 4 of the translucent sheet 4 of the sheet structure 3.
a, the envelope 1 is positioned so that the longitudinal direction of the envelope 1 is along (parallel to) the longitudinal direction of the external electrodes 5 and 6. In this state, the driven rollers 11, 11 are arranged so that the envelope 1 is slightly pressed against the translucent sheet 4.
In this state, the stage 10 is slightly moved in the M direction and then moved in the N direction. Thereby, the sheet structure 3
As shown in FIG. 11, the rare gas is wound around the outer peripheral surface of the envelope 1 and the other end 4b is overlapped with one end 4a of the translucent sheet 4 and adhered by the adhesive layer 9. The discharge lamp L is completed.

The rare gas discharge lamp L is lit by, for example, a lighting device shown in FIG. The lighting device, for example, the frequency is 25 KHz, inverter is a voltage that generates a high-frequency high voltage of about 2500V _OP, and the output waveform is substantially a sine wave - a capacitor circuit H, inverter - the supply of DC power to the capacitor circuit H , And a smoothing capacitor C. The inverter circuit H includes, for example, a primary coil TRa, TRb, a secondary coil TRc, and an exciting coil T.
An oscillation transformer TR having Rd and a primary coil TRa,
An oscillation capacitor Co connected between TRb, a choke coil CH connected between the midpoint of the primary coils TRa and TRb and the switching element Q, and a primary coil TRa and TRb.
The first and second switching elements (for example, transistors) Qa and Qb connected to TRb, and the resistor Ra connected between the bases of the first and second switching elements Qa and Qb and the exciting coil TRd. , Rb.
The output side of the inverter circuit H (the secondary coil TR
External electrodes 5 and 6 of the rare gas discharge lamp L are connected to c).

In this lighting device, when a drive signal such as a rectangular wave is applied to the terminal T3 after connecting a direct-current power supply obtained by, for example, full-wave rectification of a commercial power supply between the terminals T1 and T2, the switching element Q is turned on. The oscillating operation based on the cooperative action with the oscillating transformer TR, the oscillating capacitor Co, etc. relating to the ON / OFF of the first and second switching elements Qa, Qb causes the secondary coil TR of the oscillating transformer TR to operate.
The high-frequency high voltage described above is generated at c and applied to the external electrodes 5 and 6 of the rare gas discharge lamp L. Thus, unlike the rare gas discharge lamp L, which is lit by one discharge path along the longitudinal direction of the envelope, like a discharge lamp using a hot cathode or a cold cathode, the external electrodes 5, 6 During this period (in a direction substantially perpendicular to the longitudinal direction of the envelope 1), an infinite number of discharge paths are formed, so that the light is emitted in a striped state. In this state, the light emitting layer 2 is excited by a rare gas excitation line to emit light, and light is emitted from the aperture 2a to the outside through the first opening 7. The brightness of the rare gas discharge lamp L can be changed by appropriately setting the ON duty ratio of the drive signal applied to the terminal T3.

In particular, since no mercury is used in the rare gas discharge lamp L, the light quantity rises sharply after lighting, and the light quantity reaches almost 100% at the same time as lighting. I have. For this reason, it is suitable as a light source for reading originals in OA equipment such as a facsimile, an image scanner, and a copying machine.

If the above-described method is employed for assembling the rare gas discharge lamp, the adhesive layer 9 is provided on one surface of the translucent sheet 4.
Is formed, the sheet structure 3 can be wound around and adhered to the outer peripheral surface of the envelope 1 by a simple operation of simply rolling the envelope 1 on the sheet structure 3. , Not only can work efficiency be significantly improved,
An excellent effect such as an increase in mass productivity can be expected.

[0011]

As described above, when the rare gas discharge lamp is applied to an original irradiating apparatus, the density of the radiated light from the light emitting layer 2 can be increased by the aperture structure. Since it becomes possible, the illuminance of the document surface of, for example, about 20,000 Lx can be obtained, and the readability of the document can be improved.

However, recently, the speed of OA equipment has been increased,
From the viewpoints of improving reading accuracy and reliability, a high illuminance type rare gas discharge lamp capable of increasing the illuminance on the document surface to 30,000 to 40,000 Lx is demanded.
Various improvements are needed to meet this requirement. For example, increase the pressure of the rare gas sealed in the envelope,
Use of a lighting device (see Japanese Patent Application Laid-Open No. 9-199285) that generates a pulsed high-frequency high voltage as shown in FIG. 16 is considered to be one effective solution.

In the former solution, generally, there is a correlation between the noble gas filling pressure and brightness in a noble gas discharge lamp, and when the filling pressure is increased, brightness increases.
It is known that the brightness tends to decrease when the sealing pressure is reduced. Normally, when illuminance on the document surface of, for example, about 20,000 Lx is required, the rare gas charging pressure in the rare gas discharge lamp L is set to, for example, about 70 Torr (Torr).
By setting the above sealing pressure, the brightness is increased and the illuminance of the document surface can be increased.

However, when the rare gas charging pressure is set high as described above, the lighting device shown in FIG. 15 not only impairs the starting characteristics of the rare gas discharge lamp L but also makes the lighting state unstable. As a result, stripe-like discharges and flickers are visually observed, and this is not desirable as a light source for reading a document such as a facsimile or an image scanner, because the reading accuracy and reliability are impaired.

The latter solution is to apply a pulsed high-frequency high voltage to the rare gas discharge lamp L. Even if the rare gas filling pressure is set high as described above, the rare gas discharge lamp L
Can be improved over the lighting device shown in FIG.
High illuminance can also be expected.

In the lighting device shown in FIG.
The circuit HA comprises an oscillation transformer TRA having a primary coil TRa and a secondary coil TRc, and a switching element Q such as a transistor connected in series with the primary coil TRa of the oscillation transformer TRA or a field effect transistor (FET).
A and a capacitor CA connected in parallel with a series circuit of the primary coil TRa of the oscillation transformer TRA and the switching element QA. A rare gas discharge lamp L is connected to the output side (secondary coil TRc) of the inverter circuit HA such that a pulsed high-frequency high voltage is applied to its external electrodes 5 and 6.

This lighting device operates as follows. First, when a DC power supply that is full-wave rectified from a commercial power supply is connected to the terminals T1 and T2, the capacitor CA is charged. When a drive signal is applied to the switching element QA via the terminal T3 in this state, the switching element QA
As shown in FIG.
Is discharged to the primary coil TRa of the oscillation transformer TRA. Next, when the switching element QA is turned off, the secondary coil TRc has the state shown in FIG.
As shown in (b), a pulsed high-frequency high voltage is generated,
The rare gas discharge lamp L is turned on by being applied to the external electrodes 5 and 6 of the rare gas discharge lamp L. Therefore, according to this lighting device, even when the rare gas charging pressure in the rare gas discharge lamp L is set to be high, not only a tentative starting characteristic can be obtained, but also high illuminance can be achieved.

However, recently, the document irradiating device is OA
In some cases, the rare gas discharge lamp L is hardly irradiated with extraneous light and is almost in a dark state. Therefore, in the presence of extraneous light, the rare gas discharge lamp L in which the rare gas sealing pressure is set high is incorporated in the lighting device shown in FIG. 16, for example, with a frequency of 25 KHz and a voltage of 2500 V _OP
When a pulse-like high-frequency high voltage of about 5 mV is applied to the external electrodes 5 and 6, the light is turned on in about 1500 to 2000 mS (millisecond) or less after the voltage is applied. However, in the dark state, the light-up requires only 5000 to 6000 mS or more. Not
The variation in the lighting time also becomes extremely large, for example, some of them do not light at all. Because of this, sometimes O
The use of device A may be hindered.

The cause is considered as follows. That is, in general, a fluorescent lamp cannot be started or is difficult to start because the ionization is not performed smoothly unless initial electrons are present at the time of starting. Normally, initial electrons that trigger discharge include thermoelectrons, photoelectrons, electrons emitted by a high electric field, and cosmic rays in the natural world. However, when the rare gas discharge lamp is placed in a place completely shielded from the outside like the above-mentioned OA equipment, natural cosmic rays do not reach the rare gas discharge lamp and initial electrons can be expected. Disappears. Therefore, this kind of rare gas discharge lamp has a problem that the starting characteristics become unstable and the variation of the lighting time becomes large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rare gas discharge lamp capable of easily improving the starting characteristics in a dark state with a relatively simple structure, and a method of manufacturing the same.

[0021]

SUMMARY OF THE INVENTION Accordingly, in order to achieve the above-mentioned object, the present invention provides an envelope having a light emitting layer made of a phosphor on an inner surface thereof, and an outer peripheral surface of the envelope having substantially a light emitting layer. A pair of strip-shaped external electrodes made of a metal member arranged apart from each other over the entire length; and a cesium oxide dispersed and contained in the light emitting layer.

According to a second aspect of the present invention, there is provided an envelope having a light emitting layer made of a phosphor on the inner surface, and an outer peripheral surface of the envelope,
A pair of strip-shaped external electrodes made of a metal member arranged apart from each other over substantially the entire length thereof, and a translucent insulating member mounted on the outer peripheral surface of the envelope so as to cover the external electrodes. Wherein the light-emitting layer contains a cesium oxide dispersed therein, and the third invention is characterized in that the insulating member is made of a protective sheet made of a light-transmitting sheet or a heat-shrinkable resin. -Characterized by comprising a

According to a fourth aspect of the present invention, there is provided an envelope having a light-emitting layer made of a phosphor on an inner surface thereof, and a translucent sheet having a length substantially equal to the entire length of the envelope. A sheet structure in which a pair of strip-shaped external electrodes made of a metal member are arranged on one surface of the sheet and separated from each other, and an adhesive layer is formed on a light-transmitting sheet surface on the side where the external electrodes are located; Wherein the light-emitting layer contains cesium oxide dispersed therein, and a sheet structure is provided on the outer peripheral surface of the envelope, and an external electrode is provided between the envelope and the translucent sheet. Characterized by being wound so as to be positioned
The invention is characterized in that the light emitting layer contains cesium oxide dispersed in a range of 0.2 to 5.0% by weight based on the weight of the phosphor.

Further, a sixth invention of the present invention provides a method for forming a coating film by applying a phosphor coating solution containing at least a cesium compound and a phosphor to the inner surface of an envelope and drying the coating solution; A baking step of forming a light emitting layer by heating the envelope formed with, a step of enclosing a rare gas in the internal space of the envelope, and a pair of strip-shaped external electrodes on the outer peripheral surface of the envelope. Wherein the cesium compound is converted to a cesium oxide in the firing step. The seventh invention is characterized in that the cesium compound is cesium acetate.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the rare gas discharge lamp according to the present invention will be described with reference to FIGS. The same parts as those of the prior art shown in FIGS. 11 to 14 are denoted by the same reference numerals, and detailed description thereof will be omitted. In this figure, the characteristic part of this embodiment is that a cesium (Cs) oxide is dispersed and contained in the light emitting layer 2A formed on the inner surface of the envelope 1. Cesium oxide was added to 2A at a concentration of 0.1% based on the total weight of the phosphor.
That is, it was dispersed and contained in the range of 2 to 5.0% by weight.

By dispersing the cesium oxide in the light emitting layer 2A in this way, even if the illuminance in the installation environment of the rare gas discharge lamp is almost 0.01 Lx or less in the almost dark state, the cesium oxide Oxide content of 0.2-5.
When the content is set in the range of 0% by weight, after applying the high-frequency high voltage to the external electrodes 5 and 6, the lighting can be reliably performed in about 2000 ms or less, and the variation of the lighting time can be reduced. However, when the content of the cesium oxide is less than 0.2% by weight, not only does the lighting time exceed 3000 mS, but the variation in the lighting time also increases. Conversely, when the content of the cesium oxide exceeds 5.0% by weight, the lighting is performed in a short time, but the illuminance is greatly reduced, and it is difficult to achieve high illuminance. Therefore, the content of the cesium oxide is desirably set within the above range.

The light emitting layer 2A is formed, for example, as follows. First, a coating liquid is formed by applying a phosphor coating solution obtained by mixing a cesium compound such as cesium acetate, a phosphor, a binder, and a solvent to the inner surface of the envelope 1 and drying. Next, the envelope 1 on which the coating film is formed is baked at a temperature of, for example, about 450 to 550 ° C., thereby forming the light emitting layer 2A. At this time, the binder is removed, and the cesium compound is chemically changed to cesium oxide, and is dispersed and contained in the light emitting layer 2A. Thereafter, an aperture 2a is formed in the light emitting layer 2A, and a rare gas such as xenon gas is filled in the inner space of the envelope 1 with, for example, 80 Torr or more, preferably 100 to 150T.
The rare gas discharge lamp DL is manufactured by enclosing in orr and arranging a pair of strip-shaped external electrodes 5 and 6 on the outer peripheral surface of the envelope 1.

In particular, the light emitting layer 2A may be composed of only one kind of phosphor or a mixture of two or more kinds depending on the use of the rare gas discharge lamp. For example, in the case of a rare gas discharge lamp of a three-wavelength emission type, for example, a europium-activated barium magnesium aluminate phosphor having an emission spectrum in the blue region, and a cerium / terbium-activated phosphor having an emission spectrum in the green region. The light emitting layer is formed of a mixed phosphor obtained by mixing a lanthanum oxide phosphor and a europium-activated yttrium oxide phosphor having an emission spectrum in a red region. The attached amount of the light emitting layer 2A is set in a range of 5 to 30 mg per 1 cm ² . Although a desired light output is obtained within this range, if the amount of adhesion is less than 5 mg, the illuminance of the original surface becomes insufficient due to a decrease in the light output. It becomes difficult to form a light emitting layer. Therefore,
It is desirable that the adhesion amount of the light emitting layer 2A be set within the above range.

Further, external electrodes 5 and 6 are provided on the outer peripheral surface of the envelope 1.
Are arranged such that a first opening 7 and a second opening 8 are formed between the respective ends 5a, 6a and 5b, 6b. In particular, on the end 5b side of the external electrode 5, for example, a triangular irregular portion 5A having periodicity is formed, and the end 5a of the external electrode 5 and the end 6a of the external electrode 6,
6b is formed in a straight shape. Note that the deformed portion 5A can be formed in a rectangular shape, a semicircular shape, or the like in addition to the triangular shape.

For example, when lead glass is applied to the envelope 1, its thickness is set, for example, in the range of 0.2 to 0.7 mm, preferably in the range of 0.4 to 0.6 mm. . However, if the wall thickness is less than 0.4 mm, especially 0.2
If the thickness is less than 0 mm, the mechanical strength of the envelope 1 is extremely reduced, so that the defective rate due to glass breakage in the production process by mass production equipment increases, and conversely, the wall thickness becomes 0. When the thickness exceeds 0.6 mm, especially 0.7 mm, a striped discharge state is visually observed, and not only flickering occurs in the light emitted from the aperture portion 2a, but also the rare gas discharge lamp has sufficient power. It becomes difficult to enter. Therefore, it is desirable to set the thickness of the envelope 1 within the above range. However, as described above, if the deformed portions are formed at appropriate ends of the external electrodes 5 and 6, the thickness range of the envelope 1 can be expanded to a thicker side.

Further, first and second openings 7 and 8 are formed in the separated portions of the external electrodes 5 and 6, respectively.
The respective opening angles θ ₁ and θ ₂ are set in a relation of θ ₁ > θ ₂ . The opening angle θ ₁ of the first opening 7 is 60 to 12
In the range of 0 °, the opening angle θ ₂ of the second opening 8 is preferably about 55 °. However, the second opening 8
Is desirably small enough not to cause dielectric breakdown. For example, it is recommended to secure a separation distance of at least about 2 mm.
The opening angle of the aperture 2a is the first opening 7
Is set to be substantially the same as the opening angle θ _{1 of} .

The rare gas discharge lamp DL configured as described above
Is incorporated in, for example, the lighting device shown in FIG.
The lighting is performed after the external electrode 5 on which A is formed is grounded.
This lighting device is basically the same as that shown in FIG. 16 except that one of the external electrodes is grounded. Therefore, according to this embodiment, since the luminescent layer 2A contains the cesium oxide dispersedly in the range of 0.2 to 5.0% by weight, the light emitting layer 2A may be used in an environment where external light is blocked. Even if a high frequency high voltage in the form of a pulse is applied to the external electrodes 5 and 6 after a considerably long time (for example, about 24 hours) has passed after the light is turned off, the light is reliably turned on at approximately 2000 mS or less. And variations in lighting time can be reduced.

In the inner space of the envelope 1, 80 noble gas is contained.
It is sealed at a pressure equal to or higher than Torr, and in addition to the application of a pulsed high-frequency high voltage to the external electrodes 5 and 6, the light output emitted from the first opening 7 is effectively reduced. Can be improved. Therefore, for example, when the present invention is applied to a document irradiating device of an OA device, the illuminance of the document surface can be increased, and the reading accuracy and reliability can be improved. In addition, the amount of the light emitting layer 2A attached was ^{5 to} 30 mg / cm ² .
When set to, the light output can be further improved in combination with the above configuration.

In particular, the adhesion amount of the light emitting layer 2A is set to about 2 to 10 times as much as that of a normal fluorescent lamp for illumination, and it is considered that the characteristic is not preferable for a normal fluorescent lamp for illumination. Despite the amount, the light output of the rare gas discharge lamp is effectively increased. Although the cause is not clear, a rare light which is illuminated in a striped state by forming an infinite number of discharge paths between the external electrodes 5 and 6 (in a direction substantially perpendicular to the longitudinal direction of the envelope 1). This is considered to be a phenomenon peculiar to gas discharge lamps.

FIG. 4 shows a second embodiment of the present invention. The basic configuration is the same as that of the rare gas discharge lamp DL shown in FIG. The difference is that the end 5b of the external electrode 5 is formed in a straight shape like the end 5a, and the aperture formed on the inner surface of the envelope 1 corresponding to the first opening 7 is different. -The opening angle θ ₃ of the tea portion 2 a is set to be larger than the opening angle θ ₁ of the first opening 7. Ame - opening angle theta ₃ tea section 2a has been set, for example, in the range of 70 to 130 degrees, the application can be changed appropriately depending on the purpose. Note that the opening angles θ ₁ and θ ₂ of the openings 7 and 8 are θ ₁ >
θ ₂ is set.

According to this embodiment, as in the first embodiment, the rare gas discharge lamp can be reliably started even in an environment where external light is poor. Further, when the sheet structure 3 is wound around the outer peripheral surface of the envelope 1, even if the center between the first opening 7 and the aperture 2a is slightly shifted, the first opening is formed. The displacement of the optical axis of the light emitted from the part 7 can be reduced. For this reason, even when applied to, for example, a document irradiation device, sufficiently high reading accuracy can be obtained.

FIG. 5 shows a third embodiment of the present invention. The basic structure is the same as that of the rare gas discharge lamp DL shown in FIG. The difference is that the ends 4a and 4b of the translucent sheet 4 are superimposed on the external electrode 5,
This means that the overlapped portion was ultrasonically welded. still,
This overlapping portion can be located on the external electrode 6.

According to this embodiment, as in the first embodiment, the rare gas discharge lamp can be reliably started even in an environment where external light is poor. On top of that, a translucent sheet 4
Welding of the superposed portions 4a and 4b of the external electrodes 5
The ultrasonic vibration acting on the light emitting layer 2 </ b> A on the inner surface of the envelope is reduced because the process is performed on the outer surface side of the envelope. Therefore, as compared with the first and second embodiments, the separation of the light emitting layer 2A from the inner surface of the envelope can be suppressed, and the light output can be improved.

FIG. 6 shows a fourth embodiment of the present invention. The basic configuration is the same as that of the rare gas discharge lamp shown in FIG. The difference is that after a pair of external electrodes 5 and 6 are attached to the outer peripheral surface of the envelope 1 using an adhesive layer, a light-transmitting sheet 4A made of PET resin or the like having an adhesive layer on one surface. Is wound and adhered to the outer peripheral surface of the envelope 1 so as to cover the external electrodes 5 and 6.

According to this embodiment, as in the first embodiment, the rare gas discharge lamp can be reliably turned on even in an environment where external light is poor. In addition, before winding the translucent sheet 4A on the outer peripheral surface of the envelope 1, a translucent insulating film such as a silicone varnish may be formed on the outer peripheral surface of the envelope 1. By improving the dielectric strength between external electrodes,
Holes in the translucent sheet 4A can also be suppressed.

FIG. 7 shows a fifth embodiment of the present invention. The basic structure is the same as that of the rare gas discharge lamp shown in FIG. The difference is that after a pair of external electrodes 5 and 6 are attached to the outer peripheral surface of the envelope 1 using an adhesive layer, the protection made of a heat-shrinkable resin such as PET resin is applied to the outer peripheral surface of the envelope 1. That is, the tube 12 was mounted so as to cover the external electrodes 5 and 6, and was thermally contracted. In addition, this protection tube 1
2 is, for example, 150 to 200 ° C.
By heating and shrinking to a certain degree, it is brought into close contact with the outer peripheral surface of the envelope 1.

According to this embodiment, although the mechanization and work efficiency are inferior to those of the above-described embodiments, since the adhesive layer is not used for the protective tube 12, the terminal of any material can be used. Even when used, there is no corrosion due to the reaction between the constituent members of the terminal and the adhesive component, a stable operating state can be maintained for a long period of time, and the protective tube 12 has no seams. As in the example, peeling of the overlapping portion at the end of the translucent sheet 4 can be completely prevented.

In particular, a protective tube 1 is provided on the outer peripheral surface of the envelope 1.
Prior to mounting 2, the outer peripheral surface of the envelope 1 is
If a light-transmitting insulating film such as a varnish is formed, the dielectric strength between the external electrodes can be further increased.

FIG. 8 shows a sixth embodiment of the present invention. The basic configuration is the same as that of the rare gas discharge lamp shown in FIG. The difference is that a protective tube 12 made of a heat-shrinkable resin such as PET resin is mounted on the outer peripheral surface of the sheet structure 3 and then heat-shrinked. After the protective tube 12 is mounted on the envelope 1 (the sheet structure 3), it is heated to, for example, about 150 to 200 ° C. and shrunk, so that the outer peripheral surface of the translucent sheet 4 is formed. Adhered to.

According to this embodiment, when the environment where the rare gas discharge lamp is to be applied is under severe environmental conditions, high safety standards, etc., for example, it has excellent heat resistance, insulation properties, etc., and has translucency. By covering the sheet structure 3 with the protective tube 12, a higher quality product can be provided.

In particular, the structure of this embodiment is shown in FIGS.
6 and 7 can also be applied.

FIG. 9 shows a seventh embodiment of the present invention, in which the envelope 1 is shown in an expanded state. The basic configuration is the same as that of the rare gas discharge lamp shown in FIG. is there. The difference is that the triangular irregular portions 5A and 6A having periodicity are formed at the ends 5b and 6b of the external electrodes 5 and 6, and the tips 5Aa and 6Aa of the irregular portions 5A and 6A are different in the irregular portion pitch. Are arranged so as to face each other within 20%. In addition, the deformed portion may be formed in a rectangular shape including a trapezoid, a semicircle shape including an ellipse, or the like, in addition to the triangular shape.

The structure of the external electrode of this embodiment can be applied to the first to sixth embodiments.

The present invention is limited only to the above embodiment.
Without being, for example, as a phosphor constituting the light emitting layer
Is a cerium / terbium activated lanthanum phosphate phosphor,
In addition to europium-activated yttrium oxide phosphors,
Cerium / terbium activated magnesium aluminate fluorescence
Body (MgAl₁₁O₁₉: Ce, Tb), cerium terbi
Activated yttrium silicate phosphor (Y_TwoSiO
_Five: Ce, Tb), europium-activated barium aluminate
Magnesium phosphor (BaMg)_TwoAl₁₆O ₂₇: E
u) can also be used. The aperture in the light emitting layer
Omitted to improve the workability of winding the sheet structure around the envelope
It is also possible. Also, the overlapping of the ends of the translucent sheet
In addition to bonding, ultrasonic welding, heat welding and bonding and welding
Can also be used in combination. In addition, rare gas
The filling pressure is restricted to the range of 80 to 150 Torr.
In addition, the present invention can be applied to a rare gas discharge lamp having a low filling pressure.
In particular, in the form of an external electrode, the term “strip”
All forms are strip-shaped, as described above.
Not only at the end but also at the end
Including holes and stitches
Shall be rare. In addition, in combination with the lighting device
However, grounding of one of the external electrodes can be omitted.
You.

[0050]

Next, an experimental example will be described. First, a 10% aqueous solution of cesium acetate, a cerium / terbium-activated lanthanum phosphate phosphor, polyethylene oxide (a water-soluble binder) and water (solvent) were mixed together. 0.5mm thick and 360m long
m is applied to the inner surface of an envelope made of lead glass and fired to form a light emitting layer. In this state, the light emitting layer contains cesium oxide dispersed therein. Next, an aperture having an opening angle of 75 degrees is formed by forcibly peeling off a part of the light emitting layer using a scraper. In particular, the amount of the luminescent layer deposited was kept constant at 15 mg / cm ² , and the content of cesium oxide relative to the total weight of the phosphor after firing was in the range of 0 to 6.0% by weight as shown in FIG. Changed. Hereinafter, a rare gas discharge lamp was manufactured by the same method as the prior art shown in FIGS. The sealing pressure of the xenon gas was set to 120 Torr, and a pair of external electrodes was formed of aluminum foil having a width of 8 mm. A triangular irregular portion having a height of 1.5 mm at the apex was formed, and the other opposite end was formed in a straight shape.

The rare gas discharge lamp is incorporated in the lighting device shown in FIG.
After standing for 24 hours in a dark state of Lx or less, a frequency of 25 KHz and a voltage of 2500 V _0-P
When the pulsed high-frequency high voltage was applied and the time until the lamp was completely turned on (lighting time) and the illuminance of the document surface 8 mm away from the rare gas discharge lamp under normal lighting were measured, the results shown in FIG. 10 were obtained. Obtained.

As is clear from the figure, the lighting time of the rare gas discharge lamp shows a tendency that the lighting time in the dark state becomes shorter as the content of the cesium oxide increases, and the content of the cesium oxide increases. 2000 in the range of 0.2% by weight or more
Lights below mS. On the other hand, the illuminance tends to decrease as the content of the cesium oxide increases, and when the content exceeds 5.0% by weight, the illuminance drops below 30,000 Lx, which is a measure for increasing the illuminance. . This is presumably because cesium oxide does not contribute to light emission.
Therefore, the content of cesium oxide with respect to the light emitting layer,
It is desirable to set the range from 0.2 to 5.0% by weight from both evaluation items of the time until complete lighting and the illuminance.

[0053]

As described above, according to the present invention, since the cesium oxide is dispersed and contained in the range of 0.2 to 5.0% by weight in the light emitting layer, it is assumed that extraneous light Even if it is applied in an environment where light is shut off, after a long time has passed after the light is turned off, even if a high-frequency high voltage is applied between the external electrodes, it can be turned on reliably at almost 2000 mS or less, Time variations can be reduced.

In particular, the pressure at which the rare gas is charged is, for example, 80 To
By setting rr or more, the brightness can be improved, and when applied to a document irradiating device of OA equipment, the illuminance of the document surface can be increased and the reading accuracy and reliability can be improved.

Further, the amount of the light emitting layer to be deposited is 5 to 5 per cm ^2.
When the amount is set in the range of 30 mg, the light output can be further improved in combination with the above-described configuration.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a development view of an envelope and an external electrode portion of FIG. 1;

3 is an electric circuit diagram of a lighting device incorporating the rare gas discharge lamp shown in FIG.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a third embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a fourth embodiment of the present invention.

FIG. 7 is a longitudinal sectional view showing a fifth embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing a sixth embodiment of the present invention.

FIG. 9 is an exploded view of an envelope and an external electrode portion showing a seventh embodiment of the present invention.

FIG. 10 is a graph showing the relationship between the content of cesium oxide, the lighting time in darkness, and the illuminance during normal lighting.

FIG. 11 is a longitudinal sectional view of a rare gas discharge lamp according to the prior art.

FIG. 12 is a development view of a sheet structure according to the prior art.

FIG. 13 is a sectional view taken along line XX of FIG. 12;

FIG. 14 is a longitudinal sectional view for explaining a method for manufacturing a rare gas discharge lamp according to the prior art.

FIG. 15 is an electric circuit diagram of a lighting device for a rare gas discharge lamp according to the prior art.

FIG. 16 is an electric circuit diagram of another lighting device of the rare gas discharge lamp according to the prior art.

FIG. 17 is a diagram for explaining the operation of FIG. 16;
FIG. 3A is an operation timing chart of the switching element, and FIG. 3B is a secondary voltage waveform chart of the inverter circuit.

[Explanation of symbols]

 DL Noble gas discharge lamp HA Inverter circuit (lighting device) 1 Enclosure 2A Light emitting layer 2a Aperture 3 Sheet structure 4, 4A Translucent sheet (insulating member) 4a, 4b End 5 , 6 External electrode 5A, 6A Deformed portion 7 First opening 8 Second opening 9 Adhesive layer 12 Protective tube (insulating member)

Claims (7)

[Claims] 1. An envelope having a light emitting layer made of a phosphor on an inner surface thereof, and a pair of band-like outer members made of a metal member arranged on an outer peripheral surface of the envelope over substantially the entire length thereof. A rare gas discharge lamp comprising: an electrode; and a cesium oxide dispersed and contained in the light emitting layer. 2. A pair of band-like outer members each comprising an envelope having a light emitting layer made of a phosphor on an inner surface thereof and a metal member arranged on the outer peripheral surface of the envelope over substantially the entire length thereof. An electrode and a light-transmitting insulating member mounted on the outer peripheral surface of the envelope so as to cover the external electrode, wherein the light-emitting layer contains cesium oxide dispersed therein. Noble gas discharge lamp. 3. The rare gas discharge lamp according to claim 2, wherein the insulating member is formed of a protective tube made of a translucent sheet or a heat-shrinkable resin. 4. An envelope having a light-emitting layer made of a phosphor on an inner surface thereof, and a pair of translucent sheets having a length substantially equal to the entire length of the envelope, made of a metal member on one surface. A sheet structure in which band-shaped external electrodes are spaced apart from each other, and an adhesive layer is formed on a light-transmitting sheet surface on the side where the external electrodes are located; And the sheet structure is wound around the outer peripheral surface of the envelope so that the external electrode is located between the envelope and the translucent sheet. Rare gas discharge lamp characterized. 5. The luminescent layer according to claim 1, wherein the cesium oxide is dispersed and contained in the range of 0.2 to 5.0% by weight based on the weight of the phosphor. A rare gas discharge lamp according to any one of the above. 6. A step of forming a coating film by applying a phosphor coating solution containing at least a cesium compound and a phosphor on the inner surface of the envelope and drying the envelope, and heating the envelope on which the coating film is formed. Baking step of forming a light emitting layer by doing, a step of enclosing a rare gas in the inner space of the envelope, and a step of arranging a pair of strip-shaped external electrodes on the outer peripheral surface of the envelope, A method for producing a rare gas discharge lamp, comprising converting a cesium compound into a cesium oxide in a firing step. 7. The method for producing a rare gas discharge lamp according to claim 6, wherein the cesium compound is cesium acetate.