WO2005015607A1

WO2005015607A1 - Plasma lamp and manufacturing method thereof

Info

Publication number: WO2005015607A1
Application number: PCT/KR2004/001968
Authority: WO
Inventors: Sung-Youl Kim
Original assignee: Expantech Co., Ltd.
Priority date: 2003-08-08
Filing date: 2004-08-05
Publication date: 2005-02-17

Abstract

The present invention relates to plasma lamp with a dielectric waveguide, emitting light by reaction of electromagnetic wave received from the dielectric waveguide with noble gas and luminary filled up in the bulb, and manufacturing method thereof. In the present invention, by tightly sealing the portion of the waveguide in contact with the outer surface of the bulb, the durability of the lamp can be improved and the stable operation of the lamp at high temperatures can be achieved.

Description

PLASMA LAMP AND MANUFACTURING METHOD THEREOF

Technical Field

The present invention relates to a plasma lamp with a dielectric waveguide, emitting light by reaction of electromagnetic wave received from a dielectric waveguide with noble gas and luminary filled up in the bulb and a method for manufacturing the same. More particularly, in accordance with the present invention, by tightly sealing the portion of the waveguide in contact with the outer surface of the bulb, the durability of the lamp can be improved and the stable operation of the lamp at high temperatures can be achieved.

Background Art

As it is widely known, a plasma lamp is an electrodeless lamp capable of providing a bright white spot light source and thus, finds various applications such as in street lightening, high resolution monitors, projection TVs, and the like, since it has a longer life than an electrode lamp and can provide a brighter light source with a constant

spectrum. A conventional electrodeless plasma lamp is constructed in a manner that a bulb

comprising a luminary and inert gas within it is placed in a cavity resonator, and then, the luminary and inert gas are reacted with electromagnetic wave to emit light. Examples of such electrodeless plasma lamps are disclosed in USP No.4,954,755 by Lynch et al., USP No.4,975,625 by Lynch et al., USP No.4,978,891 by Ury et al, USP No.5,021,704 by

Walker et al, USP No.5,448,135 by Simpson, USP No.5,594,303 by Simpson, USP No.5,841,242 by Simpson, USP No.5,910,710 by Simpson, USP No.6,031,333 by Simpson, etc.

The above cavity resonator includes a cavity which is filled up with air, and is made of a metallic material to enable a maximal emission of visible light as well as receiving of the electromagnetic energy.

The lamp is filled with any one of the followings: a noble gas mixed with luminary, a compound containing a second element or sulfur(S)/selenium(Se), a compound containing S or Se, or a metal-halide element. In the above-described prior arts, electromagnetic energy is guided through a waveguide to a cavity in the cavity resonator after having been produced normally by an electron tube or solid state electronics. Once the microwave energy with selected frequency is resonated in the air filled cavity, the real resonant frequency depends on the shape and dimension of the cavity. Here, the actual power source is limited between 1 to 10GHz microwave, even when some allowable error in driving frequency of the lamp is given. However, since a plasma lamp applicable to such a cavity resonator needs to satisfy the resonance conditions in the cavity of a cavity resonator, the dimension of the cavity shall not be smaller than the half-wavelength of microwave energy generally used for operation of the lamp. In other words, a plasma lamp of the above mentioned type has a lower limit in its dimensions so that its application in products such as high resolution monitors, brighter

lamps, projection TVs, etc. finds various barriers. Furthermore, such a lamp has a complicated construction and its manufacturing cost is very high.

In addition, although a plasma lamp of the above type requires intensive microwave for initial ignition for making the noble gas plasmatic, a problem of heat loss

arises here as a half or more of the total energy used for generation and maintenance of the plasma goes lost as heat, whereby stains and/or heat spots that reduces luminous efficiency

of the lamp are produced on lamp surface. In this connection, methods for reducing heat spots by dispersing plasma in the lamp through rotation of the lamp and by causing continuous air stream in the lamp have been suggested. However, such methods are disadvantageous in that they require additional technical means and lead to a larger dimensional lamp as well as to a higher cost. Accordingly, a plasma lamp having a minimal dimension, requiring less energy for ignition and maintenance of plasma, and capable of effectively difiusing the heat is desired. A plasma lamp comprising dielectric waveguide for overcoming these drawbacks of a conventional plasma lamp with cavity resonator has been disclosed in US Patent Application Serial No.09/809,718 filed on March 5, 2001 (hereinafter, "the Prior Application"). The Prior Application discloses a plasma lamp construction capable of igniting plasma using a low level of energy and of effectively diffusing the heat generated by operation of the lamp.

Fig. 1 is a drawing showing construction of the plasma lamp disclosed in the Prior Application, wherein the plasma lamp 101 comprises an electromagnetic radiator 115, a dielectric waveguide 103 having a body made of dielectric material, and a feed 117 which

connects the radiator 115 to the waveguide 103. The waveguide 103 which locks up the

electromagnetic energy (preferably, microwave energy) and then, transmits the same to a cavity 105 facing the waveguide 103.

The term "waveguide", namely, refers to a device not merely for transmission of

electromagnetic energy, but, at least at parts, also for lock up thereof in the Prior

Application. Such usage of the term "waveguide" applies in the same way to the description of the present invention hereinafter. A lamp bulb 107 consisting of an outer wall 109 and a cover 111 is installed in the cavity 105, the bulb 107 being filled up with gas that forms plasma and emits light when an electromagnetic energy of prescribed frequency and intensity is supplied thereto. The outer wall 109, combined with the cover 111 through seal 113, forms bulb envelope 127 that contains fill up gas including plasma generating gas and luminary, wherein an inert gas such as argon (Ar) is used as the plasma generating gas and solid indium bromide (InBr) or indium iodide (Inl) is used as the luminary. The cover 111 is sealed through an airtight seal 113 with the waveguide 103 to cover opening of the cavity 105 in a manner that the fill up gas is tightly sealed within the bulb 107, and is preferably made of sapphire or quartz having superior transluminant characteristics and a thermal expansion coefficient similar to that of the waveguide 103.

In the above described construction of plasma lamp, the feed 117, which is designed to transmit electromagnetic energy, preferably microwave energy, from radiator

115 to bulb 107, and the bulb 107 are located at a position having a maximal electric field of the resonant frequency to the waveguide 103. The waveguide 103, which can be

manufactured in various sizes and shapes based on the frequency of microwave in use and the dielectric constant of dielectric material forming the waveguide, is preferably made of

an inorganic material such as alumina or quartz. According to this construction of plasma lamp 101, microwave energy, after

having been transmitted from radiator 115 through feed 117 to a cavity 105 formed at waveguide 103, triggers the noble gas filled in the bulb 107 to become plasmatic by

separating electrons from the same, whereby the separated free electrons excite luminaries in the bulb 107 so that light is emitted.

On the other hand, the above plasma lamp 101 reaches during operation thereof a high temperature between 700°C and 1000°C dependent on its size and shape. However, a luminary such as InBr, having a boiling point of about 300^° C though this temperature may vary at different atmosphere and pressure of the inert gas such as Ar, etc, is vaporized at operation temperature of the plasma lamp between 700°C and 1000°C. However, a plasma lamp as per the Prior Application requires a process of combining the outer wall 109 of the bulb 107 with the cover 111 by sealing in a state the bulb 107 is filled up with luminary such as InBr and noble gas. This leads to a problem that luminary such as InBr is vaporized and emitted to the atmosphere when the temperature arises to 300°C or more during the sealing process. Accordingly, a perfect sealing process is needed to ensure that luminary such as InBr is not vaporized and emitted to the atmosphere during the outer wall 109 of bulb 107 filled up with Ar gas and InBr, etc. is combined with the cover 111 by sealing. Even when the cover 111 and outer wall 109 of the bulb 107 are tightly sealed

with each other using a low-temperature organic material (epoxy, etc.) at temperatures below 300°C, the polymer state of this organic sealing material could be dissolved and tight sealing of the bulb 107 could fail at operation temperature of the lamp between 700°C and

1000°C, as the organic material is stabilized for temperatures at 300°C or below. Here arises the problem that luminary such as InBr filled in the bulb 107 could be vaporized and

emitted out steadily. From this background, the present invention aims to provide a lamp structure and

a lamp sealing method, wherein tight sealing of the lamp is maintained at high temperatures between 700°C and 1000°C through application of an inorganic sealing material capable of maintaining sealing function also at relatively high temperatures, and thus, a steady emission of gas filled in the bulb is prevented.

Disclosure of the Invention The present invention, conceived to solve the above problems, aims to provide a plasma lamp and a manufacturing method thereof, allowing an easy fill up of gas in the bulb and preventing emission of the gas filled in the bulb into atmosphere even under high operation temperatures of the lamp. Another object of the present invention is to provide a plasma lamp manufacturing method that allows an easy fill up of gas in the bulb and prevents vaporization of the luminary filled in the bulb as well as emission thereof to atmosphere during sealing process of the lamp. A further object of the present invention is to provide a plasma lamp with a highly enhanced luminous intensity and a more compact size. Still another object of the present invention is to provide a plasma lamp that

allows to easily compensate changes in resonant frequencies following the temperature changes, in view of the fact that the resonant frequencies are changed sensitively as the

dielectric constants of the dielectric waveguide are changed depending on the temperature changes.

In order to achieve the above objects, the present invention provides in its first embodiment a plasma lamp comprising a waveguide which is made of a dielectric material

and is connected to an electromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, wherein the waveguide comprises a first cavity formed concavely at one end thereof and a second cavity formed to penetrate from the first cavity through the waveguide to the other end thereoζ whereby the first cavity of the waveguide is combined by sealing to a bulb cover, while the second cavity of the waveguide is combined by sealing to a bulb receptor made of an inorganic material showing dielectric characteristics; and a bulb cavity filled up with inert gas and luminary is formed at one end of the bulb receptor adjacent to the bulb cover. Second embodiment of the present invention provides a plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, wherein the waveguide comprises a first cavity

formed concavely at one end thereof, a second cavity formed to penetrate from the first cavity through the waveguide to the other end thereof, and a fourth cavity having a width

wider than that of the second cavity formed at the other end of the second cavity, whereby the first cavity of the waveguide is combined by sealing to a bulb cover, while the second

cavity and the fourth cavity of the waveguide are combined by sealing to a bulb receptor made of an inorganic material showing dielectric characteristics; a bulb cavity filled up

with inert gas and luminary is formed at one end of the bulb receptor adjacent to the bulb cover, and a step portion for insertion into the fourth cavity is formed at the other end of the

bulb receptor. Third embodiment of the present invention provides a plasma lamp comprising a

waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, wherein the waveguide comprises a first cavity formed concavely at one end thereof and a second cavity formed to penetrate from the first cavity through the waveguide to the other end thereof, whereby the first cavity of the waveguide accepts a bulb cover, and the second cavity accommodates a hollow sealing tube, while contacting surfaces between the bulb cover and the sealing tube are combined with each other by sealing, and a bulb receptor is combined by sealing in the inside of the sealing tube; the bulb receptor as well as the sealing tube are made of inorganic material showing dielectric characteristics; and a bulb cavity filled up with inert gas and luminary is formed at one end of the bulb receptor adjacent to the bulb cover. Fourth embodiment of the present invention provides a plasma lamp comprising a

waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is

capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, wherein the waveguide comprises a first cavity

formed concavely at one end thereof and a second cavity formed to penetrate from the first cavity through the waveguide to the other end thereof, whereby the first cavity of the

waveguide accepts a bulb cover and the second cavity accommodates a bulb receptor made of an inorganic material showing dielectric characteristics, while contacting surfaces

between the bulb cover and the sealing tube are combined with each other by sealing; and a bulb cavity filled up with inert gas and luminary is formed at one end of the bulb receptor adjacent to the bulb cover and an injection path is formed to penetrate from the bulb cavity to the other end of the bulb receptor, the opening of injection path being tightly sealed after inert gas and luminary have been filled.

The present invention enables an easy filling of gas into a bulb, and can effectively prevent outward emission of the gas filled in the bulb at high lamp operation temperatures. Further, the present invention provides a sealing process, wherein a steady emission of the gas filled in the lamp following use of the lamp is prevented, filling of the gas into the lamp is eased, and vaporization and outward emission of the luminary filled in the bulb during the sealing process is prevented. In addition, the present invention provides a plasma lamp having a strongly enhanced luminous intensity and a more compact size.

Finally, the present invention can easily compensate the changes in the resonant frequencies following temperature changes, in consideration of the fact that changes in

dielectric constants of a dielectric waveguide caused by a temperature change lead to

changes in the resonant frequencies. Brief Description of the Drawings

Fig. 1 is a drawing showing the construction of a conventional plasma lamp. Fig. 2 shows a plane perspective view and a bottom perspective view

exemplifying stmcture of a waveguide of a plasma lamp in accordance with the first embodiment of the present invention.

Fig. 3 shows cross-sectional views of a plasma lamp in accordance with the first embodiment of the present invention. Fig. 4 shows views illustrating the manufacturing process of a plasma lamp in accordance with the first embodiment of the present invention. Fig. 5 shows cross-sectional views of a plasma lamp in accordance with the second embodiment of the present invention. Fig. 6 shows views illustrating the manufacturing process of a plasma lamp in accordance with the second embodiment of the present invention. Fig. 7 shows cross-sectional views of a plasma lamp in accordance with the third embodiment of the present invention. Fig. 8 shows views illustrating the manufacturing process of a plasma lamp in accordance with the third embodiment of the present invention. Fig. 9 shows cross-sectional views of a plasma lamp in accordance with the fourth embodiment of the present invention. Fig. 10 shows views illustrating the manufacturing process of a plasma lamp in

accordance with the fourth embodiment of the present invention. Fig. 11 is a plane view showing a bulb cover and waveguide of a plasma lamp in

accordance with the first and the second embodiments of the present invention. Fig. 12 is a cross-sectional view exemplifying a plasma lamp in accordance with

the fifth embodiment of the present invention. Fig. 13 is a cross-sectional view exemplifying a plasma lamp in accordance with the sixth embodiment of the present invention. Fig. 14 is a cross-sectional view exemplifying a plasma lamp in accordance with

the first through sixth embodiments of the present invention with additional support wall. Fig. 15 illustrates a plasma lamp in accordance with still another embodiment of

the present invention. Fig. 16 illustrates an alternative embodiment of the plasma lamp of Fig. 15.

Preferred Embodiments of the invention The preferred embodiments of the present invention are described below in detail referring to the accompanying drawings. Fig. 2 shows drawings exemplifying stmcture of a waveguide of a plasma lamp in accordance with the first embodiment of the present invention. As in the above described prior arts, a plasma lamp as per the present invention comprises a dielectric waveguide (hereinafter, the "waveguide") as a means for transmission of microwave energy from an electromagnetic energy source to a bulb, the waveguide being made of a dielectric material,

preferably of an inorganic material such as alumina, quartz, and the like, whereby the term "waveguide" refers to a device used, at least partly, for lock up of the electromagnetic

energy. As illustrated in Fig. 2(a), a concave first cavity CI is formed at one end of the

waveguide 200, and a second cavity C2 having a diameter smaller than that of the first cavity CI is formed at the lower part of the first cavity CI, the second cavity C2 penetrates

through the waveguide 200 to reach the other end thereof. Further, as Fig. 2 (b) exemplifies, additional third cavities C3 can be fonned at the

other end of the waveguide 200 for installation of a feed (not shown) that transmits microwave energy from an electromagnetic energy source (not shown), a feedback (not

shown), a sensor (not shown) for sensing changes in the dielectric constant of the dielectric, etc. around the second cavity C2, into which a bulb receptor 202 is inserted. Although Fig. 2 illustrates the waveguide 200 in cylinder form, the present invention is not limited thereto, but rather, allows any other shape such as a rectangular prism, a globe form, a complex irregular form, etc. to be adopted for the waveguide 200, provided that the waveguide 200 effectively transmits microwave energy which constitutes the electromagnetic energy source (not shown) from the feed (not shown) to the bulb 205 (c Fig. 3). A detailed description of the consfruction of the first CI, the second C2, and the third C3 cavities is given below referring to Fig. 3. As shown in Fig. 3(a), waveguide 200 as per the first embodiment of the present invention comprises at one end thereof a first cavity CI, into which a bulb cover 201 to be explained later is inserted, and a second cavity C2 formed to penetrate from the first cavity

CI through the waveguide 200 to the other end thereof, into which a bulb receptor 202 to be explained later is inserted as well as one or more third cavity C3 at the other end thereof

for installation of attachments such as feed, feedback, sensor, etc, and the second cavity C2 has a diameter smaller than that of the first cavity CI. Further, the waveguide 200 shall

preferably be made of an inorganic dielectric material that is not oversensitive to temperature changes and is resistant to corrosions by luminaries, such as alumina, quartz,

etc. Since it is obvious to those skilled in the art that the third cavity C3 for installation

of feed and the second cavity C2 for installation of bulb receptor 202 shall be placed at positions corresponding to maximal electromagnetic field of the resonant frequency of the microwave, a further explanation thereon is omitted. Here, as the first cavity CI, into which a bulb cover 201 is to be inserted, has a consfruction such that its lower part accommodates a bulb cavity 203, it also functions to determine position of the bulb 205. Fig. 3(b) is a cross-sectional view illustrating a bulb cover 201 to be inserted into the first cavity CI and a bulb receptor 202 to be inserted into the second cavity C2 of the waveguide 200. The bulb cover 201 is made of an oxide or non-oxide material having excellent translucency and a thermal expansion coefficient similar to that of the waveguide 200, such as sapphire (AI2O3), quartz (Siθ2), calcium fluoride (CaF_), cubic zirconia (ZrO_), and the like, and has the form of a thin circular plate to fit into the first cavity C 1. The bulb receptor 202 comprising at one end a bulb cavity 203 to be filled with luminary and inert gas and having a diameter smaller than that of the cover 201, is shaped in cylinder form to fit into the second cavity C2, and can be made of various inorganic material showing dielectric characteristics. The bulb receptor 202 shall preferably be made of a dielectric material having a

dielectric constant similar to or different from that of the waveguide 200, or of an inorganic material capable of embodying dielectric characteristics of an oxide or non-oxide material

that is not oversensitive to temperature changes and is resistant to corrosions by luminaries, such as alumina (AI2O3), quartz (Siθ2), alumina nitride (ADM), boron nitride (BN), silicon

nitride (Si3N4), etc. The first embodiment of the present invention provides a plasma lamp

construction, wherein first a bulb cover 201 is inserted into the first cavity CI, whereupon a first sealing connection SI is formed by tightly sealing contacting surfaces of the first cavity CI with the bulb cover 201 at a temperature over the lamp operation temperature between 700°C and 1000°C; and then, a bulb receptor 202 is inserted into the second cavity C2, whereupon a second sealing connection S2 is formed by tightly sealing contacting surfaces of the second cavity C2 with the bulb receptor 202 at a temperature over the lamp operation temperature between 700°C and 1000°C, as shown in Fig. 3(c). By tightly sealing the opening of the bulb cavity 203 formed at one end of the bulb receptor 202 through a bulb cover 201 in a state it is filled with luminary and inert gas, a plasma bulb 205 capable of emitting light by plasma reaction of the luminary and the inert gas is manufactured. Although the above bulb receptor 202 and the bulb cover 201 are described to have a cylinder or a circular plate fonn, respectively, the bulb receptor 202 and the bulb cover 201 of the present invention are not limited thereto, but rather, allow rectangle or any other shape, provided that it is easily inserted into and installed at the prescribed position. In contrast to the Prior Application (U.S. Patent Application Serial No. 09/809,718), wherein a bulb cavity is formed in the waveguide monolithically, and then, a

cover is sealed over it after the gas, etc. have been filled, the plasma lamp constmction as per the first embodiment of the present invention has a consfruction, wherein a bulb 205

filled with luminary and inert gas is formed by a bulb cavity 203 of the bulb receptor 202 and a bulb cover 201 provided separately from the waveguide 200, the bulb cover 201 is

tightly sealed with the first cavity CI of the waveguide 200 at a temperature over the lamp operation temperature between 700°C and 1000°C, and then, the bulb receptor 202 is

tightly sealed at the same high temperature after having been inserted into the opening at the other end of the second cavity C2, whereby it is advantageous in that not only filling of gas in the bulb is eased, but also a steady emission of the gas filled in the bulb into atmosphere due to a failure of the sealing caused by long time use of the lamp at high

temperatures can be prevented. Now, a description of the method for manufacturing a plasma lamp as per the first embodiment example of the present invention follows making reference to Fig. 4. Fig. 4 shows views illustrating manufacturing process of a plasma lamp in accordance with the first embodiment of the present invention. Although the plasma lamp manufacturing method as per the first embodiment of the present invention adopts the basic principles of the Prior Application comprising a dielectric waveguide connected to an electromagnetic energy source and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, it aims to provide a plasma lamp manufacturing method, wherein the problem of emission of the gas filled in the bulb into atmosphere due to a failure of the sealing by high temperatures caused by operation of the lamp is solved and filling of gas in the bulb is eased.

For these ends, the plasma lamp manufacturing method as per the first embodiment of the present invention comprises the following five steps: In the first step, a

concave first cavity CI is formed at one end of the waveguide 200, a second cavity C2, having a diameter smaller than that of the first cavity CI is formed to penetrate from the

first cavity CI through the waveguide 200 to the other end thereof, a bulb cover 201 to be

inserted into the first cavity CI and a bulb receptor 202 to be inserted into the second cavity

C2 are processed, and a bulb cavity 203 of the bulb receptor 202 is formed (cf. Fig. 4(a)). Although there exists no specific limitation as to the forms and constmctions of the first cavity CI as well as of the second cavity C2, of the bulb cover 201 as well as of the bulb receptor 202, etc, they shall preferably be conformed to the forms and constructions of the plasma lamp as per the first embodiment of the present invention. In the second step, a first sealing connection SI is formed in a manner that contacting surfaces of the bulb cover 201 with the first cavity CI of the waveguide 200 (especially, the boundary surfaces to the outside) are tightly sealed at a temperature over operation temperature of the lamp between 700°C and 1000°C in atmosphere, after the bulb cover 201 has been inserted into the first cavity CI of the waveguide200 (cf. Fig. 4(b)). Here, the sealing material shall preferably be a high-temperature inorganic composition, such as plumbic oxide (PbO), silicon dioxide (SiO_), alumina (AI2O3), boron oxide (B2O3), etc. In the present embodiment, an emission of the gas filled in the bulb 205 into atmosphere due to a dissolving of the sealing during use of the lamp can be prevented by application of a high-temperature inorganic sealing material that can maintain its sealing

function at temperatures on or over the operation temperature of the lamp between 700°C and 1000°C. In the third step, luminary is filled into a bulb cavity 203 of the bulb receptor 202 in the atmosphere of inert gas, whereupon the second cavity C2 is also filled with the inert

gas in the atmosphere of the inert gas, thus, the bulb cavity 203 of the bulb receptor 202 is filled naturally with luminary and inert gas.

Here, a noble gas such as argon (Ar), which can become plasmatic under application of microwave energy, is preferably used for the inert gas, while for the

luminary a metal-halide group element, such as rare-earth element halide, natrium halide, indium-halide, mercury, etc. is used. In particular, when InBr or M, which is sensitive to impurities such as oxygen, humidity, and the like, is used for luminary, the above process shall be performed in a highest possible pure (i.e. impurity such as oxygen, humidity, and the like has been eliminated) atmosphere of the inert gas. In the fourth step, the bulb receptor 202 is inserted into the second cavity C2 of the waveguide 200 in the atmosphere of inert gas such that the bulb cavity 203 of the bulb receptor 202 contacts the bulb cover 201 (cf. Fig. 4(c)). As shown in the drawing, the bulb receptor 202 comprising the bulb cavity 203 is formed separately from the waveguide 200 and inserted into the second cavity C2 formed at the waveguide 200 in the atmosphere of the inert gas such as Ar in the above plasma lamp manufacturing method of the present invention, thus, filling process of the inert gas and of the luminary into the bulb cavity 203 is much eased in comparison to the Prior Application. In the fifth step, a second sealing connection S2 is formed by tightly sealing the

contacting surfaces (especially, the boundary surfaces to the outside) of the other end of the bulb receptor 202 with the second cavity C2 of the waveguide 200 at a temperature over the operation temperature of the lamp between 700°C and 1000°C in the atmosphere of inert gas. Here, since the luminary filled in the bulb cavity 203, such as InBr, etc.

commences to boil and vaporize in the atmosphere of Ar, etc. at a temperature about 300°C, the second sealing process is performed at temperature over the operation temperature of

the lamp between 700°C and 1000°C, and at the same time, one end of the waveguide 200 adjacent to the bulb cavity 203 is cooled by a cooling means 208 in a manner that the

temperature in the bulb cavity 203 of the bulb receptor 202 is maintained to be below the boiling point of the luminary filled in the bulb (cf. Fig. 4(d)).

For such cooling, various cooling means including an air cooling and/or a water cooling can be adopted, and the sealing material used herein is the same as one used in the above second step. Fig. 5 shows cross-sectional views of a waveguide 200 and a bulb receptor 202 of the plasma lamp in accordance with the second embodiment of the present invention. As shown in Fig. 5(a), a waveguide 200 in accordance with the second embodiment of the present invention comprises at one end thereof a concave first cavity CI, into which a bulb cover 201 to be explained later is inserted, and a second cavity C2 formed to penetrate from the first cavity CI through the waveguide 200 to the other end thereof, into which a bulb receptor 202 to be explained later is inserted. Further, the waveguide 200 comprises at the other end thereof one or more third cavity C3 for installation of attachments such as feed, feedback, sensor, etc. The second cavity C2 has a diameter smaller than that of the first cavity CI, while a fourth cavity C4 having a diameter

larger than that of the second cavity C2 is provided at the other end of the second cavity C2 (i.e. the part facing the first cavity CI).

Fig. 5(b) is a cross-sectional view of the bulb cover 201 to be inserted into the first cavity CI and of the bulb receptor 202 to be inserted into the second cavity C2 of the

waveguide 200. As shown in the drawing, the bulb cover 201 has a form of thin circular plate to fit into the first cavity CI, while the bulb receptor 202 comprises at one end thereof

(i.e. the end adjacent to the first cavity CI) a bulb cavity 203 to be filled with luminary and

inert gas, and at the other end a step portion 204 to be combined with the above fourth cavity C4. The bulb receptor 202 is formed as a long cylinder with a diameter smaller than that of the cover 201, to fit into the second cavity C2. The second embodiment of the present invention provides a plasma lamp construction, wherein a bulb cover 201 is inserted into the first cavity CI, whereupon a first sealing connection SI is formed by tightly sealing contacting surfaces of the first cavity CI with the bulb cover 201 at a temperature over the lamp operation temperature between 700°C and 1000°C; and then, a bulb receptor 202 is inserted into the second cavity C2, whereupon a second sealing connection S2 is formed by tightly sealing contacting surfaces of the fourth cavity C4 with the step portion 204 of the bulb receptor 202 at a temperature over the lamp operation temperature between 700°C and 1000°C, as shown in Fig. 5(c). By tightly sealing the opening of the bulb cavity 203 formed at one end of the bulb receptor 202 tlirough a bulb cover 201 in a state it is filled with luminary and inert gas, a plasma bulb 205 capable of emitting light by plasma reaction of the luminary and the

inert gas is manufactured. In the plasma lamp constmction as per the second embodiment of the present invention a bulb 205 filled with luminary and inert gas is formed by a bulb cavity 203 of the bulb receptor 202 and a bulb cover 201 provided separately from the waveguide 200,

the bulb cover 201 is tightly sealed with the waveguide 200 at a temperature over the lamp operation temperature between 700°C and 1000°C, and then, the step portion 204 of the

bulb receptor 202 is tightly sealed at the same high temperature after having been inserted into the fourth cavity C4. Consequently, a plasma lamp as per the second embodiment of

the present invention is advantageous in that not only filling of gas in the bulb is eased, but

also a steady emission of the gas filled in the bulb into atmosphere due to a failure of the sealing caused by long time use of the lamp at high temperatures can be prevented as in the

first embodiment. As a second sealing connection S2 is formed at contacting surfaces of the step portion 204 of the bulb receptor 202 with the fourth cavity 204 of the waveguide 200 in the second embodiment, this step makes the sealing construction firmer and enhances the sealing performance in comparison to the first embodiment of the present invention. Now, a description of the method for manufacturing a plasma lamp in accordance with the second embodiment of the present invention follows referring to Fig. 6. Fig. 6 shows views illustrating the manufacturing process of a plasma lamp as per the second embodiment of the present invention. Although the plasma lamp manufacturing method as per the second embodiment of the present invention adopts the basic principles of the Prior Application as in the first embodiment, it aims to provide a plasma lamp manufacturing method, wherein not only the Prior Application's problem of emission of the gas filled in the bulb into atmosphere due to a failure of the sealing by high temperatures caused by operation of the lamp is solved and filling of gas in the lamp is

eased, but also, a firmer sealing constmction as well as an enhanced sealing performance are provided in contrast to the first embodiment.

For these ends, the plasma lamp manufacturing method as per the second embodiment of the present invention comprises the following five steps: In the first step, a

concave first cavity CI is formed at one end of the waveguide 200, a second cavity C2 is formed to penetrate from the first cavity CI through the waveguide 200 to the other end

thereof, a fourth cavity C4 having a diameter larger than that of the second cavity C2 is

formed at the other end of the second cavity C2, and a bulb cover 201 to be inserted into the first cavity CI and a bulb receptor 202 having a bulb cavity 203 as well as a step portion 204 are processed (cf. Fig. 6(a)). Although there exists no specific limitation as to

the forms and constmctions of the first cavity CI as well as of the second cavity C2, of the bulb cover 201 as well as of the bulb receptor 202, etc, they shall preferably be conformed to the forms and constmctions of the plasma lamp as per the second embodiment of the present invention. In the second step, a first sealing connection SI is formed in a manner that contacting surfaces of the bulb cover 201 with the first cavity CI of the waveguide 200 (especially, the boundary surfaces to the outside) are tightly sealed at a temperature over the operation temperature of the lamp between 700°C and 1000°C in atmosphere, after the bulb cover 201 has been inserted into the first cavity CI of the waveguide200 (cf. Fig. 6(b)). Here, the sealing material shall preferably be a high-temperature inorganic composition, such as plumbic oxide (PbO), silicon dioxide (Siθ2), alumina (AI2O3), boron oxide (B2O3), etc. In the present embodiment, an emission of the gas filled in the lamp into atmosphere due to a dissolving of the sealing during use of the lamp can be prevented by

application of a high-temperature inorganic sealing material that can maintain its sealing function at temperatures on or over the operation temperature of the lamp between 700°C

and 1000°C. In the third step, luminary is filled into a bulb cavity 203 of the bulb receptor 202

in the atmosphere of inert gas, whereupon the second cavity C2 of the waveguide 200 is also filled with the inert gas in the atmosphere of the inert gas, thus, the bulb cavity 203 of

the bulb receptor 202 is filled naturally with luminary and inert gas. Here, a noble gas such as argon (Ar), which can become plasmatic under

application of microwave energy, is preferably used for the inert gas, while for the luminary metal-halide group element, such as rare-earth element halide, natrium halide,

indium-halide, mercury, etc. is used. In particular, when InBr or Inl, which is sensitive to impurities such as oxygen, humidity, and the like, is used for luminary, the above process shall be performed in a highest possible pure (i.e. impurity such as oxygen, humidity, and the like has been eliminated) atmosphere of the inert gas. In the fourth step, the bulb receptor 202 is inserted into the second cavity C2 of the waveguide 200 (cf. Fig. 6(c)) in the atmosphere of inert gas such that step portion 204 of the bulb receptor 202 is inserted into the fourth cavity C4 of the waveguide 200 while the bulb cavity 203 of the bulb receptor 202 contacts the bulb cover 201. The bulb receptor 202 comprising the bulb cavity 203 is formed separately from the waveguide 200 and inserted into the second cavity C2 formed at the waveguide 200 in the atmosphere of inert gas such as Ar in the above plasma lamp manufacturing method of the present invention, thus, filling process of the plasma firming gas and the luminary into

the bulb cavity 203 is much eased in comparison to the Prior Application. In the fifth step, a second sealing connection S2 is formed by tightly sealing

contacting surfaces (especially, the boundary surfaces to the outside) of the step portion of the bulb receptor 202 with the second cavity C2 of the waveguide 200 at a temperature

over the operation temperature of the lamp between 700°C and 1000°C in the atmosphere of inert gas. Here, since the luminary filled in the bulb cavity 203, such as InBr, etc.

commences to boil and vaporize in the atmosphere of Ar, etc. at a temperature about 300°C, the second sealing process is performed at temperature over the operation temperature

between of the lamp 700°C and 1000°C, and at the same time, one end of the waveguide 200 on which the bulb cover 201 has been sealed is cooled by a cooling means 208 in a manner that the temperature in the bulb cavity 203 of the bulb receptor 202 is maintained to be below the boiling point of the luminary filled in the lamp (cf Fig. 6(d)). For such cooling, various cooling means 208 including an air cooling and/or a water cooling can be adopted, and the sealing material used herein is the same as one used in the above second step. Fig. 7 shows cross-sectional views of a waveguide 200 and of a bulb receptor 202 in accordance with the third embodiment of the present invention. As shown in Fig. 7(a), waveguide 200 as per the third embodiment of the present invention comprises at one end thereof a first cavity CI, into which a bulb cover 201 to be explained later is inserted, and a second cavity C2 formed to penetrate from the first cavity CI through the waveguide 200 to the other end thereof, into which a bulb receptor 202 to be explained later is inserted. Further, the waveguide 200 comprises at the other end thereof one or more third cavity C3 for installation of attachments such as feed, feedback,

sensor, etc. The second cavity C2 has a diameter smaller than that of the first cavity CI . Fig. 7(b) is a cross-sectional view of the bulb cover 201 to be inserted into the first

cavity CI and of the sealing tube 206 as well as of the bulb receptor 202 to be inserted into the second cavity C2. As shown in the drawing, the bulb cover 201 has a form of thin

circular plate to fit into the first cavity CI, the sealing tube 206 having a form of hollow tube is inserted into the second cavity C2, and the sealing tube 206 accepts a bulb receptor

202. The bulb receptor 202 is formed as a long cylinder having a smaller diameter than that of the cover 201 to fit into the second cavity C2, comprises at one end thereof (i.e. the end

adjacent to the first cavity CI) a bulb cavity 203 to be filled with luminary and inert gas and is made of a material similar to or same as that of the sealing tube 206. The third embodiment of the present invention provides a plasma lamp constmction, wherein a first sealing connection SI is formed by tightly sealing contacting surfaces of the bulb cover 201 with the sealing tube 206 at a temperature over the lamp operation temperature between 700°C and 1000°C; then, a bulb receptor 202 is inserted into the sealing tube 206 such that the bulb cavity 203 contacts the bulb cover 201, whereupon a second sealing connection S2 is formed by tightly sealing contacting surfaces of the sealing tube 206 with the bulb receptor 202 at a temperature over the lamp operation temperature between 700°C and 1000°C; and finally, by simply bonding contacting surfaces of the bulb cover 201 with the first cavity CI of the waveguide 200 and/or contacting surfaces of the sealing tube 206 with the second cavity C2 of the waveguide 200, whereby creating a first bonding connection and/or a second bonding connection (Bl, B2), as shown in Fig. 7(c). By tightly sealing opening of the bulb cavity 203 formed at one end of the bulb receptor 202 in a state it is filled with luminary and inert gas through a bulb cover 201, a plasma bulb 205 capable of emitting light by plasma reaction of the luminary and the inert

gas is manufactured. Meanwhile, in the first sealing connection SI of the first and of the second

embodiment of the present invention, as contacting surfaces of the bulb cover 201 with the waveguide 200 are sealed by an inorganic sealing material, in case the bulb cover 201 and

the waveguide 200 are made of different materials, the first sealing connection SI can fail

due to cracks or breakages on the bulb cover 201 and/or on the first sealing connection SI,

caused by different thermal expansions coefficients of the materials used, progressing in radial directions (arrow direction P) of the waveguide 200 as shown in Fig. 11,. In order to solve this problem, a sealing tube 206 having a smaller thickness than that of the waveguide 200 is tightly sealed to the lower part of the bulb cover 201 to form a first sealing connection SI in the third embodiment of the present invention, so that a danger of cracking and break down of the first sealing connection SI as in the first and the second embodiment of the present invention can be removed. Although the above sealing tube 206, the bulb receptor 202, and the bulb cover

201 are described to have a tubular, a cylinder, and a circular plate form, respectively, the sealing tube 206, the bulb receptor 202 and the bulb cover 201 of the present invention are not limited thereto, but rather, allow any other shape, provided that it is easily inserted into and installed at the prescribed position. The third embodiment of the present invention provides a plasma lamp consfruction, wherein a bulb 205 filled up with luminary and inert gas is formed by a bulb cavity 203 of a bulb receptor 202, a sealing tube 206, and a bulb cover 201 provided

separately from the waveguide 200, the bulb cover 201 is tightly sealed with the sealing tube 206 at a temperature over the lamp operation temperature between 700°C and 1000°C,

and then, the other end of the bulb receptor 202 is inserted into the sealing tube 206 to be tightly sealed at the same temperature, so that filling process of the gas into the bulb is

more eased, and a steady emission of the gas filled in the bulb into the atmosphere by a failure of the sealing function caused by a long time use of the lamp at high temperatures

can be prevented, in comparison to the first and second embodiments of the present

invention. Further, as the third embodiment of the present invention provides not only a first sealing connection SI between the sealing tube 206 and the bulb cover 201, but also a second sealing connection S2 between the bulb receptor 202 and the sealing tube 206, the sealing consfruction becomes firmer and the sealing performance is enhanced in comparison to the first and second embodiments of the present invention. Now, a description of the method for manufacturing a plasma lamp as per the third embodiment of the present invention follows making reference to Fig. 8. Fig. 8 shows views illustrating the manufacturing process of a plasma lamp as per the third embodiment of the present invention. Although the plasma lamp manufacturing method as per the third embodiment of the present invention adopts the basic principles of the Prior Application as in the first embodiment, it aims to provide a plasma lamp manufacturing method, wherein not only the Prior Application's problem of emission of gas and luminary filled in the bulb into atmosphere due to a failure of the sealing by high temperatures caused by operation of the lamp is solved and filling of gas and luminary in the bulb is eased, but also, a more enhanced sealing performance is enabled in comparison to the first and second embodiments as well as a break down of the first sealing connection SI due to the difference in the thermal expansion coefficients between the bulb cover 201

and the waveguide 200 as it may occur in the first and second embodiments is prevented. For these ends, the plasma lamp manufacturing method as per the third

embodiment of the present invention comprises the following five steps: In the first step, a concave first cavity CI is formed at one end of the waveguide 200, a second cavity C2 is

formed to penetrate from the first cavity CI through the waveguide 200 to the other end thereof, and a bulb cover 201 to be inserted into the first cavity CI and a sealing tube

2026as well as a bulb receptor 202 to be inserted into the second cavity C2 are processed (cf Fig. 4(a)). Although there exists no specific limitation as to the forms and constmctions of the first cavity CI as well as of the second cavity C2, of the bulb cover 201 as well as of the bulb receptor 202, etc, they shall preferably be conformed to the forms and constmctions of the plasma lamp as per the third embodiment of the present invention. Lithe second step, contacting surfaces of the bulb cover 201 with the sealing tube 206 (especially, the boundary surfaces to the outside) are tightly sealed using an inorganic sealing material at a temperature over the operation temperature of the lamp between 700°C and 1000°C in atmosphere, whereby forming the first sealing connection SI (cf. Fig. 8(b)). This process aims to prevent a break down of the first sealing connection SI between the bulb cover 201 and the first cavity CI of the waveguide 200 due to the difference in the thermal expansion coefficients as it may occur in the first and second embodiments of the present invention. Here, the sealing material shall preferably be a high-temperature inorganic composition, such as plumbic oxide (PbO), silicon dioxide (Siθ2), alumina (AI2O3), boron oxide (B2O3), etc. In the present embodiment example, an emission of gas filled in the bulb

into atmosphere due to a dissolving of the sealing during use of the lamp can be prevented by application of a high-temperature inorganic sealing material that can maintain its sealing function at temperatures on or over the operation temperature of the lamp between 700°C

in the atmosphere of inert gas, and then, the bulb receptor 202 is inserted into the sealing tube 206 in a manner that the bulb cavity 203 contacts the bulb cover 201 (cf. Fig. 8(c)). Here, a noble gas such as argon (Ar), which can become plasmatic under application of microwave energy, is preferably used for the inert gas, while for the luminary metal-halide group element, such as rare-earth element halide, natrium halide, indium-halide, mercury, etc. is used.

In particular, when InBr or Inl, which is sensitive to impurities such as oxygen, humidity, and the like, is used for luminary, the above process shall be performed in a highest possible pure (i.e. impurity such as oxygen, humidity, and the like has been eliminated) atmosphere of the inert gas. In the fourth step, a second sealing connection S2 is formed by tightly sealing contacting surfaces of the other end of the sealing tube 206 with the other end of the bulb receptor 202 at a temperature over the operation temperature of the lamp between 700°C and 1000°C in the atmosphere of inert gas. Here, since the luminary filled in the bulb cavity 203, such as InBr, etc. commences to boil and to vaporize in the atmosphere of Ar, etc. at a temperature about 300°C in order to prevent volatilization of the luminary during the sealing process, this sealmg process is performed at temperature over the operation temperature of the lamp between 700°C and 1000°C, and at the same time, one end of the bulb cover 201 is cooled by a cooling means 208 in a manner that the temperature in the

bulb cavity 203 of the bulb receptor 202 is maintained to be below the boiling point of the luminary filled in the lamp (cf. Fig. 8(d)).

For such cooling, various cooling means 208 including an air cooling and/or a water cooling can be adopted, and the sealing material used herein is the same as one used

in the above second step. In the fifth step, a first bonding connection Bl and/or a second bonding

connection B2 are formed by inserting the bulb cover 201 and the sealing tube 206 into the first cavity CI and the second cavity C2 of the waveguide 200, respectively, and then, by simply bonding contacting surfaces of the bulb cover 201 with the first cavity CI of the waveguide 200 and/or contacting surfaces of the sealing tube 206 with the second cavity of

the waveguide 200 (cf. Fig. 8(e)). In this process, the combination made in the preceding process between the bulb cover 201 and the sealing tube 206, and the bulb receptor 202 are inserted into the first cavity CI and the second cavity C2, respectively, and then firmly combined, for which process various room-temperature (or high temperature)-hardening inorganic bonds can be used. Fig. 9 shows cross-sectional views of a waveguide 200 and of a bulb receptor 202 of a plasma lamp in accordance with the fourth embodiment of the present invention. As shown in Fig. 9(a), waveguide 200 as per the fourth embodiment example of the present invention comprises at one end thereof a first cavity CI, into which a bulb

cover 201 to be explained later is inserted, and a second cavity C2 formed to penetrate from the first cavity CI through the waveguide 200 to the other end thereof, into which a

bulb receptor 202 comprising a bulb cavity 203 and an injection path 207 are inserted. Further, the waveguide 200 comprises at the other end thereof one or more third cavity C3

for installation of attachments such as feed, feedback, sensor, etc. The second cavity C2 has a diameter smaller than that of the first cavity CI.

Fig. 9(b) is a cross-sectional view of the bulb cover 201 to be inserted into the first cavity CI and of the bulb receptor 202 to be inserted into the second cavity C2 of the

waveguide 200. As shown in the drawing, the bulb cover 201 has a form of thin circular plate to fit into the first cavity CI, the bulb receptor 202 made of a dielectric material

comprises at one end thereof a bulb cavity 203 to be filled with luminary and inert gas, and an injection path 207 penefrating from the bulb cavity 203 to the other end of the bulb

receptor 202 is formed. Here, the injection path 207 has a possible minimal diameter allowing injection of the luminary into the bulb cavity 203. As shown in Fig.9(c), the fourth embodiment of the present invention provides a plasma lamp construction, wherein a first sealing connection SI is formed by tightly sealing contacting surfaces of the bulb receptor 202 with the bulb cover 201 at a temperature over the lamp operation temperature between 700°C and 1000°C while the bulb cavity 203 contacts the lower part of the bulb cover 201; then, opening of the injection path 207 is tightly sealed after luminary as well as the inert gas have been injected through the injection path 207 of the bulb receptor 202 at a temperature over the lamp operation temperature between 700°C and 1000°C, whereupon a second sealing connection S2 is

formed. By tightly sealing the bulb cavity 203 formed at one end of the bulb receptor 202 with the bulb cover 201 and with the sealing stmcture of the injection path 207 in a state it

is filled with luminary and inert gas, a plasma bulb 205 capable of emitting light by plasma reaction of the luminary and the inert gas is manufactured. The plasma lamp construction as per the fourth embodiment example of the present invention, in which an injection path 207 is tightly sealed at a temperature over the

lamp operation temperature between 700°C and 1000°C, after luminary and inert gas have been injected through the injection path 207 of the bulb receptor 202, provides a plasma

lamp capable of avoiding clearance (assembly allowance) that is created inevitably when the bulb receptor 202 is inserted into the second cavity C2 of the waveguide 200 or into the

sealing tube 206 as in the first through third embodiments of the present invention, capable of preventing emission of the gas filled in the bulb 205 through the clearance, and thus,

capable of enhancing the luminous intensity of the lamp. Now, a description of the method for manufacturing a plasma lamp as per the fourth embodiment example of the present invention follows making reference to Fig. 10. Fig. 10 shows views illustrating the manufacturing process of a plasma lamp as per the fourth embodiment of the present invention. Although the plasma lamp manufacturing method as per the fourth embodiment of the present invention adopts the

basic principles of the above embodiments comprising a dielectric waveguide connected to an electromagnetic energy source and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from the waveguide while the bulb is connected to the waveguide, it aims to provide a plasma lamp manufacturing method, wherein not only a steady emission of the gas filled in the bulb 205 into atmosphere through the clearance between the bulb receptor 202 and the waveguide

200 is prevented, but also the luminous intensity of the lamp is enhanced.

For these ends, the plasma lamp manufacturing method as per the fourth embodiment of the present invention comprises the following five steps: In the first step, a

first cavity CI and a second cavity C2 are formed at the waveguide 200, and a bulb cover

201 to be inserted into the first cavity CI as well as a bulb cavity 203 and an injection path

of the bulb receptor 202 to be inserted into the second cavity C2 are processed (cf. Fig. 10(a)). Although there exists no specific limitation as to the forms and constructions of the

first cavity CI as well as of the second cavity C2, of the bulb cover 201 as well as of the

bulb receptor 202, etc, they shall preferably be conformed to the forms and constmctions of the plasma lamp as per the fourth embodiment of the present invention. In the second step, contacting surfaces of the bulb cover 201 with the bulb receptor 202 are tightly sealed using an inorganic sealing material at a temperature over the operation temperature of the lamp between 700°C and 1000°C in atmosphere, whereby forming the first sealing connection SI (cf. Fig. 10(b)). Here, the sealing material shall preferably be a high-temperature inorganic composition, such as plumbic oxide (PbO), silicon dioxide (Siθ2), alumina (AI2O3), boron oxide (B2O3), etc. In the present embodiment example, an emission of the gas filled in the bulb 205 into atmosphere due to a dissolving of the sealing during use of the lamp can be prevented by application of a high-temperature inorganic sealing material that can maintain its sealing function at temperatures on or over the operation temperature of the lamp between 700°C and 1000°C. In the third step, luminary and inert gas are filled into a bulb cavity 203 of the bulb receptor 202 through the injection path 207 in the atmosphere of inert gas. (cf Fig. 10(c)).

luminary metal-halide group element, such as rare-earth element halide, natrium halide, indium-halide, mercury, etc. shall be used.

In particular, when InBr or Inl, which is sensitive to impurities such as oxygen,

humidity, and the like, is used for luminary, the above process shall be performed in a

highest possible pure (i.e. impurity such as oxygen, humidity, and the like has been eliminated) atmosphere of the inert gas. As shown in the drawing, the method for manufacturing plasma lamp of the

present embodiment provides a consfruction, wherein luminary is filled up through an injection path 207 of the bulb receptor 202 installed at the waveguide 200 in the atmosphere of inert gas such as argon (Ar), and this method enables an easy filling up of inert gas as well as, of luminary, in comparison to the Prior Application and the first through third embodiments of the present invention. In the fourth step, a second sealing connection S2 is formed by tightly sealing the opening of the injection path 207 of the bulb receptor 202 at a temperature over the operation temperature of the lamp between 700°C and 1000°C in the atmosphere of inert gas, after the gas has been filled in the bulb cavity 203. Here, since the luminary filled in the bulb cavity 203, such as InBr, etc. commences to boil and to vaporize in the atmosphere of Ar, etc. at a temperature about 300°C in order to prevent volatilization of the luminary during the sealing process, this sealing process is performed at temperature over the operation temperature of the lamp between 700°C and 1000°C, and at the same time, one end of the bulb cover 201 is cooled by a cooling means 208 in a manner that the temperature in the bulb cavity 203 of the bulb receptor 202 is maintained to be below the boiling point of the luminary filled in the bulb (cf. Fig. 10(d)). For such cooling, various cooling means 208 including an air cooling and/or a water cooling can be adopted, and the sealing material used herein is the same as one used

in the above second step. In the fifth step, a first bonding connection Bl and /or a second bonding

connection B2 are formed by inserting the bulb cover 201 and the bulb receptor 202 into the first cavity CI and the second cavity C2 of the waveguide 200, respectively, and then,

by simply bonding contacting surfaces of the bulb cover 201 with the first cavity CI of the

waveguide 200 and/or by simply bonding contacting surfaces of the bulb receptor 202 with

the second cavity C2 of the waveguide 200 (cf. Fig. 10(e)). In this process, the combination made in the preceding process between the bulb cover 201 and the bulb receptor 202 is firmly combined with the waveguide 200, for which process various room temperature (or high temperature) hardening inorganic bonds can be used. In the third and fourth embodiments of the present invention, the sealing processes of the bulb cover 201 and of the bulb receptor 202 are performed separately from the waveguide 200 which has a relatively larger volume, i.e. first the bulb cover 201 is sealed with the bulb receptor 202, then, they are inserted into the first and second cavities CI, C2 of the waveguide 200, respectively, and finally simply bonded together, as described above. Accordingly, in contrast to the first and second embodiments, the third and fourth embodiments of the present invention are capable of preventing cracks and break downs between the waveguide 200 and the bulb cover 201 as well as between the waveguide 200 and the bulb receptor 202 caused by an irregular thermal distribution during the sealing process. Further, as the sealing process between the bulb cover 201 and the bulb receptor

202 is performed separately, the space needed in the sealing equipment becomes smaller, thus, the above methods are fit to a mass production. Same effects can also be achieved in the process of filling inert gas and luminary into the bulb cavity 203. As described above, the cooling process adopted in the plasma lamp

manufacturing method of the first through fourth embodiments of the present invention is a process of cooling the bulb cover 201 adjacent to the bulb cavity 203 for the purpose of

preventing vaporization of the luminary in the bulb cavity 203 due to the high temperature

caused by the sealing process while the luminary is filled in the bulb cavity 203.

Such cooling process of the present invention is not limited to the plasma lamp manufacturing method as per the first through fourth embodiments of the present invention, but rather, can be applied to various plasma lamp manufacturing methods, wherein a bulb is formed within a waveguide by tightly sealing a bulb cavity while the bulb cavity to be formed within a waveguide is filled with inert gas and luminary. Fig. 12 is a cross-sectional view exemplifying a plasma lamp in accordance with the fifth embodiment of the present invention. As shown in the drawing, the lamp comprises a monolithic cavity C5 formed lengthwise, having the same diameter (i.e. formed in a manner that the first cavity CI and the second cavity C2 in the first through fourth embodiments to have the same diameter) and other elements are same as in the first through fourth embodiments. In other words, in contrast to the first through fourth embodiments, wherein position of bulb 205 formation is determined by the first cavity CI which has a diameter

larger than that of the second cavity C2, the present embodiment provides a lamp consfruction, wherein position of bulb 205 formation can be adjusted to the resonant frequency supplied, in view of the fact that a bulb formation position corresponds to the maximum electric field of the resonant frequency supplied from an elecfromagnetic energy

source (not shown) through a feed (not shown). Thus, the present embodiment allows a bulb 205 formation position to be adjusted

to the resonant frequency, by suitably adjusting the size of the bulb cover 201 as well as of the bulb receptor 202 to be inserted into the monolithic cavity C5 having the same diameter. However, in the above first through fifth embodiments of the present invention,

the bulb cover 201 can easily be destroyed, if the temperature difference between inside of the bulb 205 and outside of the bulb cover 201 exceeds a certain thermal resistance limit. A sixth embodiment is provided to solve this problem, as shown in Fig. 13. As shown in Fig. 13, in the sixth embodiment of the present invention, a bulb receptor 202 (in the third embodiment together with the sealing tube 206) is inserted into the monolithic cavity C5 of the above fifth embodiment by a predetermined depth, a first bulb cover 201a is attached on the upper part of the bulb cavity 203 of the bulb receptor 202, a second bulb cover 201b is attached to the opening of the waveguide 200, and a gap 215 having a predetermined distance is provided between the first and the second bulb cavities (201a, 201b). In the sixth embodiment, thermal difference between internal and external temperatures of the bulb 205 can be overcome by moving the first and the second bulb covers 201 a, 20 lb by the distance of the gap 215, so that the thermal resistance limits of the first and second bulb covers 201a, 201b are enhanced, thus, desfruction of the first and the second bulb covers 201a, 201b can be prevented. Further, as shown in Fig. 14, the first through the fifth embodiments of the present

invention can additionally comprise supporting walls 209 made of an inorganic material between outer surface of the bulb receptor 202 (or outer surface of the sealing tube in case

of the third embodiment) and inner surfaces of the waveguide 200 (i.e. inner surfaces foπned by the first cavity CI, the second cavity C2, or the monolithic cavity C5).

Such supporting walls 209 are formed to wrap the outer walls of the bulb receptor 202 and the sealing tube 206 of the above first through fifth embodiments and to be

inserted into the waveguide 200. For these supporting walls 209, e.g. an inorganic material having excellent

dielectric characteristics can be applied for enhancement of the electric characteristics, or an inorganic material having a low theπnal conductivity can be applied for improving the

thermal isolation. The correlation between the dielectric constant and the resonant frequency can be

expressed by the following Formula 1 : [Formula l]

(Here,_/o: resonant frequency, c: light velocity, D: form factor, ε _r: dielectric constant) For a waveguide 200 or a bulb receptor 202 in the above first through fourth embodiments of the present invention, an inorganic material not very sensitive to temperature changes such as alumina or quartz is used considering other conditions such as metal corrosion by luminary. Normally, such dielectrics have an intrinsic temperature

gradient, i.e. dielectric constant of the dielectrics changes dependent on the temperature changes. Since a resonant frequency is changed corresponding to a change in the dielectric constant by the above temperature gradient (as expressed in the above Formula 1), a correction corresponding to the change in the resonant frequency becomes necessary. For correction of such changes in resonant frequencies, the prior art further comprises a sensor for sensing changes in the resonant frequencies of a dielectric, requiring

an additional constmction for correction of the changes. Thus, the present invention adopts a dielectric material having a small dielectric

change of dielectric constant by a temperature change, in view of the fact that dielectric constant of a dielectric is changed dependent on a temperature change.

In addition, when a dielectric material having a high dielectric constant is used for a waveguide of the present invention, the total dimension of the waveguide can be compacter, since a dielectric constant and a form factor are in inverse proportion to each other at a same resonant frequency as it can be known from the above Formula 1, thus, the form factor becomes smaller in inverse proportion to the dielectric constant of the waveguide. Alternatively, a dielectric waveguide of the present invention can be made of a material having a low dielectric constant change by temperature changes and a high dielectric constant, such as one selected from a mixture of Ba(CoιaNb2/3)O group and

Ba(Znι/3Nb2β)O group (about 35 relative dielectric constant), Zn-xSnxTiθ3 group (about 38 relative dielectric constant), Ba(Zni/3Ta2fl)O3 group (about 30 relative dielectric constant), CaTiθ3-LaA_2θ3 group (about 43 relative dielectric constant) and CaTiO3-NdAbO3 group

(about 43 relative dielectric constant). In the above-described embodiments, a magnesium oxide (MgO) coating layer can be formed on surfaces of the bulb cover 201 adjacent to the bulb cavity 203(in the sixth

embodiment, the first bulb cover 201a). Such MgO coating layer can enhance resistance (endurance) of the bulb against

the plasma generated by the luminary filled in the bulb cavity 203, and prevent corrosion of the bulb cover 201 by the luminary.

A waveguide 200 constmction comprising a bulb 205 of a plasma lamp in accordance with the first through sixth embodiments of the present invention can be

applied to a variety of resonant modes, such as a dielectric resonant mode, a cavity

resonant mode, a mixture of both resonant mode, etc.

Preferably, the outer surface of a waveguide 200 as per the present invention except for the part for acceptance of the bulb cover 201 additionally comprises a plating layer (not shown) made of a conductive metal thereon. Figs. 15 and 16 illustrate plasma lamp constmctions in accordance with other embodiments of the present invention, wherein a waveguide 200 comprising a bulb 205 is embodied in a cavity resonator 30. In this other embodiment of a plasma lamp of the present invention, a waveguide 200 comprising a bulb 205 formed as per any one of the above first through sixth embodiments is supported by a supporting bed 35 at an arbitrary position within a cavity resonator 30, the cavity resonator 30 comprising an frradiation opening 31 for outward radiation of the light emitted from the bulb 205 at upper part thereof a feed 32 for transmission of microwave energy from an electromagnetic energy source (not shown) to the cavity resonator 30 and the waveguide 200 at one side thereoξ a feedback 33 at the other side thereo and a resonant frequency compensator 40 for fine coπection of the resonant frequencies generated in the cavity resonator 30.

The cavity resonator 30 having outer walls made of metallic material with a high conductivity, is filled with air, and can take various forms such as a hexahedron, a cylinder, etc. A cavity resonator 30 as per the present embodiment, being a device for transmission of microwave energy from the elecfromagnetic energy source (not shown) to the bulb 205, and for at least partial capture of the electromagnetic energy, has an object

comparable with that of a waveguide 200, but its inner cavity is filled with air. The dielectric waveguide 200 comprising a bulb 205 formed as per any one of the

above first through sixth embodiments is installed at a position in the cavity resonator 30 coπesponding to the maximal electric field of resonant frequency and is supported by a supporting bed 35. The irradiation opening 31 is provided at the upper part of the cavity resonator 30 to allow outward radiation of the light emitted from the bulb 205 of the dielectric waveguide 200. The feed 32, which is installed at one side of the cavity resonator 30(the opposite side of the fees 32), transmits microwave energy from the elecfromagnetic energy source (not shown) to the cavity resonator 30 and the dielectric waveguide 200. The feedback 33, which is installed at the other side of the cavity resonator 30, probes the cavity resonator 30 and the dielectric waveguide 200, samples the field (including amplitude and phase information), and then, feeds back by inputting the sample into the electromagnetic energy source (not shown) or into the amplifier.

The resonant frequency compensator 40 is a device for coπecting position of the dielectric waveguide 200 or of the iπadiation opening 31 to compensate the frequency

changes caused by a change in the dielectric constant, since dielectric constant of a dielectric waveguide 200 changes by temperature changes.

As shown in Fig. 15, preferably, a resonant frequency compensator 40 performs fine corrections of the resonant frequencies by compensating the changing dielectric

constants of the air in the cavity resonator 30 and the dielectric waveguide 200 to the changing temperatures, while the supporting body 35 that supports the dielectric waveguide 200 makes up/down movements at the lower part of the cavity resonator 30. The supporting body 35 has a consfruction, wherein a male screw 35a is formed at the outer surface of the supporting body 35, while a through hole 37 comprising a coπesponding female screw is provided at the lower part of the cavity resonator 30, such that movements of the supporting body 35 via the screws are enabled. The resonant frequency compensator 40 can alternatively be made as a moving body 41 as in Fig. 16, wherein the moving body 41 is installed in the cavity resonator 30 in a manner that up/down movements of the moving body 41 through the iπadiation opening 31 are enabled, the moving body 41 comprising a through hole 41a for outward radiation of the light emitted from the bulb 205 of the waveguide 200 as well as a male screw 41b at outer surface thereof, in a manner that movements of the moving body 41 via the male screw are enabled, so that fine coπections of the resonant frequencies are enabled by compensating changes in the dielectric constants of the air in the cavity resonator 30 and of the dielectric waveguide 200 as the temperature changes. As described above, a plasma lamp in accordance with the above embodiments of the present invention can make dimensions of a plasma lamp more compact in comparison to a conventional plasma lamp using a cavity resonator, due to its novel construction,

wherein a cavity resonator includes a dielectric waveguide having a dielectric constant different from that of the air.

Although the present invention has been described above using prefeπed

embodiments of the present invention and the drawings, it is not limited thereto, but rather, the scope of rights of the present invention shall be determined by the claims appended

herein and their equivalents, as those skilled in the art will understand, allowing various adaptations, modifications, and changes without departing from the gist and spirit of the

invention.

Claims

What is claimed is:

1. A plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert

gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from said waveguide while said bulb is connected to said waveguide, wherein said waveguide comprises a first cavity formed concavely at one end thereof and a second cavity formed to penetrate from said first cavity through the waveguide to the other end thereof, whereby said first cavity of said waveguide is combined by sealing to a bulb cover, while said second cavity of said waveguide is combined by sealing to a bulb receptor made of an inorganic material showing dielectric characteristics; and a bulb cavity filled with inert gas and luminary is formed at one end of said bulb receptor adjacent to said bulb cover.

2. A plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert gas as well as luminary and is .capable of emitting light upon receiving electromagnetic energy from said waveguide while said bulb is connected to said waveguide, wherein said waveguide comprises a first cavity formed concavely at one end thereof, a

second cavity formed to penetrate from said first cavity through the waveguide to the other end thereof and a fourth cavity having a diameter larger than that of said second cavity

formed at the other end of said second cavity, whereby said first cavity of said waveguide is combined by sealing to a bulb cover, while

said second cavity and said fourth cavity of said waveguide are combined by sealing to a bulb receptor made of an inorganic material showing dielectric characteristics; and a bulb cavity filled with inert gas and luminary is formed at one end of said bulb

receptor adjacent to said bulb cover, and a step portion to be inserted into the fourth cavity

is formed at the other end of the bulb receptor.

3. A plasma lamp comprising a waveguide which is made of a dielectric material

and is connected to an electromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from said waveguide while said bulb is connected to said waveguide, wherein said waveguide comprises a first cavity formed concavely at one end thereof and a second cavity formed to penetrate from said first cavity through the waveguide to the other end thereof, whereby said first cavity of said waveguide accepts a bulb cover, said second cavity of said waveguide accommodates a hollow sealing tube, contacting surfaces of said bulb cover with said sealing tube are combined with each other by sealing , and a bulb receptor is inserted into said sealing tube and combined by sealmg; and said bulb receptor as well as said sealing tube are made of an inorganic material capable of embodying dielectric characteristics, and a bulb cavity filled with inert gas and luminary is formed at one end of said bulb receptor adjacent to said bulb cover.

4. A plasma lamp comprising a waveguide which is made of a dielectric material

and is connected to an elecfromagnetic energy source, and a bulb which is filled up with inert gas as well as luminary and is capable of emitting light upon receiving

electromagnetic energy from said waveguide while said bulb is connected to said waveguide, wherein said waveguide comprises a first cavity formed concavely at one end thereof and

a second cavity formed to penetrate from said first cavity through the waveguide to the other end thereof, whereby said first cavity of said waveguide accepts a bulb cover, said second cavity of said waveguide accommodates a bulb receptor made of a dielectric material, contacting surfaces of said bulb cover with said bulb receptor are combined with each other by sealing; and said bulb receptor is made of an inorganic material capable of embodying dielectric characteristics, a bulb cavity filled with inert gas and luminary is formed at one end of said bulb receptor adjacent to said bulb cover, and an injection path is formed to penetrate from said bulb cavity to the other end of said bulb receptor, and opening of said injection path is tightly sealed after said inert gas as well as said luminary have been filled therein.

5. The plasma lamp of any one of Claims 1 through 4, wherein said bulb cover is made of an oxide or non-oxide material having excellent translucency and a thermal expansion coefficient similar to that of said waveguide.

6. The plasma lamp of any one of Claims 1 through 4, wherein said sealing material is a high-temperature inorganic sealing material capable of maintaining sealing function at temperatures on or over the lamp operation temperature.

7. The plasma lamp of Claim 6, wherein said sealing material is any one of plumbic oxide (PbO), silicon dioxide (Siθ2), alumina (AI2O3), and boron oxide (B2O3).

8. The plasma lamp of any one of Claims 1 through 4, wherein said waveguide is made of a mixture consisting of one or more of alumina, quartz, a mixture of Ba(Coi/3Nb2θ)O group and Ba(Znι/3 >2/3)O group, Zπ-xSnχTiθ3 group, Ba(Zni3Ta_β)θ3 group, CaTiθ3-LaAbθ3 group and CaTiθ3-NdAl 2O3 group.

9. The plasma lamp of any one of Claims 1 through 4, wherein said luminary is made of a metal-halide material.

10. The plasma lamp of Claim 9, wherein said luminary is made of any one of rare-earth element halide, natrium halide, indium halide, or mercury.

11. The plasma lamp of any one of Claims 1 through 4, wherein said first cavity and said second cavity of said waveguide are formed as a monolithic cavity having same diameter.

12. The plasma lamp of Claim 11, wherein said bulb receptor is inserted into said monolithic cavity by a predetermined depth, a first bulb cover is attached on said bulb cavity, a second bulb cover is attached on the opening of said waveguide, and a gap is provided between said first and said second bulb covers.

13. The plasma lamp of Claim 11, additionally comprising supporting wall made of an inorganic material between the outer surface of said bulb receptor and the inner surface of said waveguide.

14. The plasma lamp of any one of Claims 1 through 4, wherein the outer surface of said waveguide additionally comprises plating layer made of conductive metallic material.

15. The plasma lamp of Claim 11, wherein the surfaces of said bulb cover adjacent to said bulb cavity additionally comprises magnesium oxide (MgO) coating layer.

16. A method for manufacturing plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a

bulb which is filled with inert gas as well as luminary and is capable of emitting light upon

receiving elecfromagnetic energy from said waveguide while said bulb is connected to said

waveguide, comprising: a first step, wherein a concave first cavity is formed at one end of said waveguide, a second cavity is formed to penetrate from said first cavity through the waveguide to the other end thereof, a bulb cover to be inserted into said first cavity of said waveguide and a bulb receptor to be inserted into said second cavity are processed, and a bulb cavity is formed at one end of said bulb receptor; a second step, wherein contacting surfaces of said bulb cover with said first cavity of said waveguide are tightly sealed at a temperature in atmosphere on or over the operation temperature of said lamp, after said bulb cover has been inserted into said first cavity of said waveguide; a third step, wherein luminary is filled into a bulb of said bulb receptor in the atmosphere of inert gas; a fourth step, wherein said bulb receptor is inserted into said second cavity of said waveguide in the atmosphere of inert gas; a fifth step, wherein contacting surfaces of said bulb receptor with said second

cavity of said waveguide are tightly sealed at a temperature in the atmosphere of inert gas on or over the operation temperature of said lamp, and at the same time one end of said

waveguide at which said bulb cover is installed is cooled in a manner that the temperature in said bulb cavity is maintained to be below the boiling point of said luminary filled in

said bulb.

17. A method for manufacturing plasma lamp comprising a waveguide which is

made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon

receiving elecfromagnetic energy from said waveguide while said bulb is connected to said waveguide, comprising: a first step, wherein a concave first cavity is formed at one end of said waveguide, a second cavity is formed to penetrate from said first cavity through the waveguide to the other end thereof a fourth cavity having a wider width than said second cavity is formed at the other end of said second cavity, a bulb cover to be inserted into said first cavity of said waveguide and a bulb receptor to be inserted into said second cavity are processed, a bulb cavity is formed at one end of said bulb receptor, and a step portion to be inserted into said fourth cavity is formed at the other end of said bulb receptor; a second step, wherein contacting surfaces of said bulb cover with said first cavity of said waveguide are tightly sealed at a temperature in atmosphere on or over the operation temperature of said lamp, after said bulb cover has been inserted into said first cavity of said waveguide; a third step, wherein luminary is filled into a bulb of said bulb receptor in the atmosphere of inert gas; a fourth step, wherein said bulb receptor is inserted into said second cavity of said waveguide in the atmosphere of inert gas; a fifth step, wherein contacting surfaces of said step portion of said bulb receptor with said fourth cavity of said waveguide are tightly sealed at a temperature in the

atmosphere of inert gas on or over the operation temperature of said lamp, and at the same time, one end of said waveguide at which said bulb cover is installed is cooled in a manner

that the temperature in said bulb cavity is maintained to be below the boiling point of said

luminary filled in said bulb.

18. A method for manufacturing plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from said waveguide while said bulb is connected to said waveguide, comprising: a first step, wherein a concave first cavity is formed at one end of said waveguide, a second cavity is formed to penetrate from said first cavity through the waveguide to the other end thereof, a bulb cover to be inserted into said first cavity of said waveguide, a hollow sealing tube to be inserted into said second cavity as well as a bulb receptor to be accommodated in said sealing tube are processed, and a bulb cavity is formed at one end of said bulb receptor; a second step, wherein said sealing tube is tightly sealed to the lower part of said bulb cover at a temperature in atmosphere on or over the operation temperature of said lamp; a third step, wherein said bulb receptor is inserted into said sealing tube, after said luminary is filled into a bulb of said bulb receptor in the atmosphere of inert gas; a fourth step, wherein contacting surfaces of said sealing tube with said bulb receptor are tightly sealed at a temperature in the atmosphere of inert gas on or over the operation temperature of said lamp, and at the same time, one end of said bulb cover is

cooled in a manner that the temperature in said bulb cavity is maintained to be below the boiling point of said luminary filled in said bulb; and a fifth step, wherein said bulb cover, and said sealing tube as well as said bulb receptor are inserted into said first cavity and said second cavity, respectively, and then,

firmly combined.

19. A method for manufacturing plasma lamp comprising a waveguide which is

made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon receiving electromagnetic energy from said waveguide while said bulb is connected to said waveguide, comprising: a first step, wherein a concave first cavity is formed at one end of said waveguide, a second cavity is formed to penetrate from said first cavity through the waveguide to the other end thereof, a bulb cover to be inserted into said first cavity of said waveguide and a bulb receptor to be inserted into said second cavity are processed, a bulb cavity is formed at one end of said bulb receptor, and an injection path penefrating from said bulb cavity to the

other end of said bulb receptor is formed; a second step, wherein said bulb receptor is tightly sealed to the lower part of said bulb cover at a temperature in atmosphere on or over the operation temperature of said

lamp; a third step, wherein luminary and inert gas are injected into said bulb cavity of said bulb receptor through said injection path in the atmosphere of inert gas; a fourth step, wherein opening of said injection path of said bulb receptor is tightly sealed at a temperature in the atmosphere of inert gas on or over the operation temperature

of said lamp, and at the same time, one end of said bulb cover is cooled in a manner that the temperature in said bulb cavity is maintained to be below the boiling point of said

luminary filled in said bulb; and a fifth step, wherein said tightly sealed bulb cover and said bulb receptor are

inserted into said first cavity and said second cavity, respectively, and then, firmly

combined.

20. The method for manufacturing plasma lamp of any one of Claims 16 through 19, wherein said inert gas atmosphere is an atmosphere of high purity grade inert gas.

21. The method for manufacturing plasma lamp of any one of Claims 16 through 19, wherein said bulb cover is made of an oxide or non-oxide material having excellent translucency.

22. The method for manufacturing plasma lamp of any one of Claims 16 through 19, wherein said sealing material is a high-temperature inorganic sealing material capable of maintaining sealing function at temperatures on or over the lamp operation temperature.

23. The method for manufacturing plasma lamp of Claim 22, wherein said sealing material is any one of plumbic oxide (PbO), silicon dioxide (Siθ2), alumina (AI2O3), and boron oxide (B2O3).

24. The method for manufacturing plasma lamp of any one of Claims 16 through 19, wherein said waveguide is made of a mixture consisting of one or more of alumina,

quartz, a mixture of Ba(Coι&Nb2/3)O group and Ba(ZniθNb2β)O group, Zπ-χSnχTiθ3 group, Ba(Zm/3Ta2/3)θ3 group, CaTiθ3-LaAkθ3 group, and CaTiθ3-NdAl 2O3 group.

25. The method for manufacturing plasma lamp of any one of Claims 16 through 19, wherein said luminary is made of a metal-halide material.

26. The method for manufacturing plasma lamp of Claim 25, wherein said luminary is made of any one of rare-earth element halide, natrium halide, indium halide, or

mercury.

27. A method for manufacturing plasma lamp by tightly sealing a bulb cavity in a

waveguide made of a dielectric material, after said bulb cavity has been filled with inert gas and luminary, comprising an additional step of cooling the parts adjacent to said bulb cavity such that the inner temperature of said bulb cavity is maintained to be below the boiling point of said luminary during said sealing process.

28. A plasma lamp comprising a waveguide which is made of a dielectric material and is connected to an electromagnetic energy source, and a bulb which is filled with inert gas as well as luminary and is capable of emitting light upon receiving elecfromagnetic energy from said waveguide while said bulb is connected to said waveguide, including a cavity resonator, of which the inner cavity is filled up with air and the outer walls are made of highly conductive metallic material; a dielectric waveguide, which is supported by a supporting bed at an arbitrary position within said cavity resonator and takes a form in accordance with any one of Claims 1 through 12; an iπadiation opening, which is provided at the upper part of said cavity resonator and can outwardly irradiates the light emitted from the bulb of said dielectric waveguide;

and a resonant frequency compensator capable of coπecting the resonant frequency

changes generated by said dielectric waveguide and said cavity resonator.

29. The plasma lamp of Claim 28, wherein said resonant frequency compensator

is installed in a manner that said supporting bed for supporting said waveguide with said bulb is allowed to make up/down movements at the lower part of said cavity resonator, and

enables fine corrections of the resonant frequencies by correcting the changing dielectric

constants of said cavity resonator and said dielecfric waveguide to the temperature changes.

30. The plasma lamp of Claim 28, wherein said resonant frequency compensator comprises a moving body which can make up/down movements through said irradiation opening of said cavity resonator, and said moving body comprises a through hole for outward irradiation of the light emitted from said bulb of said waveguide and a male screw at outer surface thereof to enable up/down movements through said irradiation opening.