The utility model content
According to the utility model, provide the technology that is used to throw light on.Particularly, the utility model provides the method and apparatus of the plasma illuminating device that uses the dielectric waveguide body with the structure that is shaped.As just example, the utility model can be applicable to various application scenarios, comprises lamp and other application scenarios in warehouse lamp, stadium lamp, the big or small building.
In an embodiment, the utility model provides a kind of plasma lamp apparatus.This lamp apparatus has a body, this body comprise at least a dielectric material and have comprise first surface and with at least one major part of first surface opposing second surface.This equipment has in the major part of passing first surface insertion body and is configured to provide to body the loop of radio-frequency (RF) energy.In a preferred embodiment, the protuberance of dielectric material is around the circumference of bulb.Preferably, bulb has first end, second end and the area of space between first end and second end, also has a predetermined volume, the bulb envelope gas filler, gas filler is positioned to from body received RF energy, and making provides the major part of electric field near area of space.In an embodiment, second surface is coated with electric conducting material.In an embodiment, at least a portion of the bulb of the feasible encapsulation of this equipment gas filler is positioned at the major part top and the contiguous second surface of body, and this equipment has a radio frequency source, this radio frequency source is coupled to second surface to provide radio-frequency (RF) energy to body, make gas filler send the major part of electromagnetic radiation by the part of area of space, this electromagnetic radiation has the lumens/watt of the amount of determining at least.
In an embodiment, bulb is made by translucent alumina material or sapphire material.
In an embodiment, radio-frequency (RF) energy circulates with about 400 to about 500MHz.
In another embodiment, radio-frequency (RF) energy circulates with about 250MHz.
In an embodiment, radio frequency source is a side diffusion mos device.
In an embodiment, radio frequency source is made by the material that comprises GaN or SiC.
In an embodiment, the lumen of determining amount is 80 and bigger or 140 and bigger or 170 and bigger.
In an embodiment, the part of the major part top that is positioned at body of the bulb of encapsulation gas filler be whole area of space 1/3rd or bigger.
In another embodiment, the part of the major part top that is positioned at body of the bulb of encapsulation gas filler be whole area of space half or bigger.
In an embodiment, the radio frequency source that is coupled to second surface is coupled to a reference potential, and wherein, radio-frequency (RF) energy is coupled to the second surface of described body basically inductively.
In the embodiment, area of space is configured to cylindrical shape.
In an embodiment, the dielectric constant of the dielectric material of body is greater than 2.
In an embodiment, dielectric material is essentially glass or quartz.
In an embodiment, the protuberance of dielectric material is from the outstanding and contiguous second surface of the major part of body and around at least a portion of bulb.
In an embodiment, further comprise around the radiator of the protuberance of solid dielectric material.
In an embodiment, further comprise being suitable for by loop so that the power supply of radio-frequency (RF) energy to be provided to body in the frequency of body interior resonance.
In an embodiment, the protuberance of dielectric material is less than the major part of the body of dielectric material.
In an embodiment, at least a portion of bulb is positioned at the top, central area of the major part of dielectric body.
In an embodiment, at least a portion that body forms an opening and bulb is positioned in the described opening.
In an embodiment, the outer surface except the surface that forms described opening of body is coated basically with electric conducting material.
In an embodiment, bulb is positioned at the top, plane that comprises described second surface.
In an embodiment, dielectric material comprises aluminium oxide.
In an embodiment, further comprise the power supply that is suitable in body, providing to body radio-frequency (RF) energy with the frequency of basic schema resonance by loop.
In an embodiment, further comprise being suitable for by loop to provide the power supply of radio-frequency (RF) energy to body in the frequency of body interior resonance, wherein, at least one size of body equal the resonant energy in the body wavelength pact half.
In an embodiment, further comprise second loop that inserts in the body.
In an embodiment, frequency is in the scope of 0.1GHz to 30GHz.
The dielectric support structure that the utility model provides a kind of bulb to be placed in one.Bulb is supported on the described structure by the protuberance that extends from the inner chamber body of supporting construction and contact around the circumference of bulb.This protuberance extends from supporting construction with bend mode, thereby has reduced the electric field that this protuberance place produces.Owing to reduced electric field, in bulb, produce plasma, thereby increased the lumens/watt feature of lamp apparatus with the low radio frequency energy level.Other modification, modification and replacement can be arranged certainly.
Utilize the utility model to realize being better than the benefit of prior art.In an embodiment, the utility model provides the method and apparatus that disposes input, output and couples back element, provide these coupling elements so that be electromagnetically coupled to bulb, the power transmission and the characterstics of frequency resonance of this bulb depend on the waveguide body with at least two kinds of materials to a great extent.In a preferred embodiment, the utility model provides a kind of and has for improving the method and the structure of the layout that manufacturing and design flexibility provide.Other execution modes can comprise the integrated package of output coupling element and bulb, and this integrated package plays a role with existing coupling element structure in the mode of complementation, also comprises the correlation technique that is used for the street lighting application scenario.In an embodiment, this method and thus obtained structure for commerce use speech relative simply and manufacture view with low cost.In a preferred embodiment, the utility model provides a kind of thus obtained more high efficiency apparatus and method that have, and adopts the circular space feature to reduce electric field etc. in one or more parts of resonator structure.According to this execution mode, can realize the one or more benefits in these benefits.These and other benefits can be described in whole specification, and will more specifically describe below.
The utility model has been realized other benefits of these benefits and known procedure technical elements.Yet,, can further understand essence of the present utility model and advantage by part and accompanying drawing with reference to this specification back.
Embodiment
According to the utility model, provide the technology that is used to throw light on.Particularly, the utility model provides the method and apparatus of the plasma illuminating device that uses the dielectric waveguide body with the structure that is shaped.As just example, the utility model can be applicable to various application scenarios, comprises lamp and other application scenarios in warehouse lamp, stadium lamp, the big or small building.
According to the utility model, provide the technology that is used to throw light on.Particularly, the utility model provides to use and has had the method and apparatus of dielectric constant less than the plasma illuminating device of 2 dielectric waveguide.More specifically, the utility model provides to have and has used the method and apparatus of dielectric constant less than the plasma illuminating device of 2 ceramic resonator structure.As just example, the utility model can be applicable to various application scenarios, comprises lamp and other application scenarios in warehouse lamp, stadium lamp, the big or small building.
Turn to accompanying drawing now, Fig. 1 shows the preferred implementation of the plasma lamp (DWIPL) 101 that is integrated with dielectric waveguide.DWIPL 101 preferably includes electromagnetic radiation (being preferably microwave radiation) source 115, have the waveguide 103 of the body that dielectric material forms and the loop 117 that radiation source 115 is coupled to waveguide 103.As used herein, the general expression of term " waveguide " has the feature of restriction (confining) electromagnetic energy and any device of purpose at least in part.DWIPL101 also comprises bulb 107, this bulb preferably is arranged on the opposite side of waveguide 103, and air inclusion filler (preferably including inert gas) and luminous element, luminous element form the concurrent bright dipping of plasma when receiving the electromagnetic energy of characteristic frequency and intensity.
In the preferred implementation of reference Figure 1A, the dielectric waveguide body comprises first material and second material at least.In a preferred embodiment, wherein a kind of dielectric constant of material is 2 and littler.According to this execution mode, this material can comprise fluid, such as gas, air or mixture etc.In a preferred embodiment, fluid is air or liquid or gas, such as the mixture of nitrogen, argon gas or these gases.In an embodiment, lower dielectric constant causes lower electric capacity and higher resonance frequency.In addition, higher resonance frequency can comprise 1GHz and littler or 500MHz and littler, but also can be other frequencies.Further, preferably, the width of waveguide body less than 5 inches (2 inches), but also can be other sizes less than about 5 inches (or 2 inches) and length.Other modification, modification and replacement can be arranged certainly.
In a preferred embodiment, microwave radiation source 115 is supplied to waveguide 103 via loop 117 with microwave energy.Waveguide comprises (contain) microwave energy and microwave energy is guided to cavity 105 on the opposite side that is preferably located in waveguide 103 from loop 117.The bulb 107 that contains gas filler is arranged in the cavity 105.Preferably, microwave energy is introduced in the cavity 105 of sealing, and then arrives in the bulb 107.Usually, microwave energy makes electronics discharge from its normal condition, thereby converts inert gas to plasma.The free electron stimulated luminescence body of inert gas.The deexcitation of luminous element (deexcitation) causes sending light.As becoming apparent, the different execution modes of DWIPL disclosed herein provide the obvious advantage that is better than plasma lamp of the prior art, such as producing brighter and the light that spectrum is more stable, higher energy efficiency, littler overall lamp size and longer useful life.
Microwave source 115 among Fig. 1 is schematically illustrated as solid electronic device, and still, other devices that can work in the 0.5-30GHz scope commonly known in the art also can be used as microwave source, include but not limited to klystron and magnetron.For the preferable range of microwave source from about 100MHz to about 20GHz.More preferably, frequency range is that 300MHz is extremely less than 1GHz.Other modification, modification and replacement can be arranged certainly.
According to the heat sensitivity of microwave source 115, microwave source 115 can with bulb 107 thermal insulations, bulb preferably reaches the temperature between about 700 degrees centigrade to about 1000 degrees centigrade during operation.Bulb 107 provides the advantage of avoiding source 115 to degenerate with the thermal insulation in source 115.Can realize the extra thermal insulation of microwave source 115 by in many known methods in the prior art any, include but not limited to, use the insulating material or the vacuum gap that occupy the optional space 116 between source 115 and the waveguide 103.If select a kind of mode in back, then use suitable microwave loop that microwave source 115 is coupled to waveguide 103.
In Fig. 1,115 loops 117 that are passed to waveguide 103 preferably include coaxial probe from the source with microwave.Yet, can use in the some kinds of dissimilar microwave loops commonly known in the art any, such as microstrip line (micro strip line) or fin line structure.
Because machinery or other considerations (such as heat, vibration, aging or impact), when being fed to microwave signal in the dielectric material, preferably, utilize positive contact mechanism 121 to keep contacting between loop 117 and the waveguide 103.Contact mechanism 121 provides constant pressure between loop 117 and waveguide 103, will reflect by loop 117 and be not passed to possibility in the waveguide 103 to minimize microwave energy.When constant pressure was provided, contact mechanism 121 compensation was because thermal shock or mechanical shock and the small size that may occur in microwave loop 117 and the waveguide 103 changes.Contact mechanism can be spring charging device (shown in Fig. 1), bellows-type device or any other device of keeping the constant pressure that is used for continuously and stably transmitting microwave energy commonly known in the art.
When loop 117 is coupled to waveguide 103, preferably, realize tight contact by the direct deposit metallic material 123 in some place that in waveguide 103, contacts with loop 117.Metal material 123 has been eliminated and may have been disturbed the gap that couples and preferably include gold, silver or platinum, but also can use other electric conducting materials.Can use in the some kinds of methods commonly known in the art any to come deposit metallic material 123, such as deposition liquid metal material 123, subsequently in stove this metal material of sintering so that the solid contact to be provided.
In Fig. 1, waveguide 103 is preferably the shape of rectangular prism, but, waveguide 103 also can have cylindrical prism shape, spherical form or any other shape, comprise preferably the complicated irregularly shaped of the resonance frequency determined by the electromagnetical analogies instrument, described waveguide can guide to bulb 107 with microwave energy from loop 117 efficiently.The actual size of waveguide can change according to the dielectric constant of the body of the frequency of employed microwave energy and waveguide 103.
In a preferred implementation, waveguide body is about 3 inches or littler, and dielectric constant is about 2 and littler, and operating frequency is about 400MHz.The waveguide body of two kinds of dielectric materials of use of this number range is significantly less than the waveguide in the traditional plasma lamp.Therefore, waveguide in this preferred implementation has shown the obvious advantage that is better than conventional lights, this is because less size allows waveguide to use in many application scenarios, can limit this use before the waveguide dimensions or make this use infeasible fully in these application scenarios.In a preferred embodiment, this method and structure provide following one or more benefits: size reduces, size reduces to change into higher power density, lower loss, and thereby lights lamp easily.Other modification, modification and replacement can be arranged certainly.
Regardless of the shape and size of waveguide, preferably, waveguide 103 has and comprises the body that for example preferably presents the dielectric material of following character: dielectric constant preferably is equal to or less than about 2, and loss factor is preferably less than about 0.0001.In other embodiments, dielectric constant is equal to or greater than 2.Other modification, modification and replacement can be arranged certainly.
Some pottery (comprising the variant or the combination of aluminium oxide, zirconia, titanate and these materials) and silicone oil can satisfy many above-mentioned optimal ways, and because their electrical characteristics and thermo-mechanical property and can being used.Under any circumstance, it should be noted that here the execution mode that proposes is not limited to present all or even the waveguide of most of aforesaid properties.In a preferred embodiment, pottery or dielectric comprise average dielectric constant less than 2 one or more holes and/or air bag, but also can be other materials.In other embodiments, dielectric constant is equal to or greater than 2.Other modification, modification and replacement can be arranged certainly.
In the various execution modes of disclosed waveguide here, in the example such as general introduction in the above, waveguide preferably provides an elementary heat quality (substaintial thermal mass), this elementary heat quality helps the effective distribution and the dissipation of heat, and provides thermal insulation between lamp and microwave source.
Described the replacement execution mode of DWIPL 200,220 among Fig. 2 A to Fig. 2 B.In Fig. 2 A, bulb 207 and bulb cavity 205 are arranged on the side of waveguide 203, preferably are arranged on the side relative with loop 209, more preferably are arranged in the plane identical with loop 209, and the electric field of microwave energy is a maximum herein.Provide in waveguide 203 under the situation of more than electric field maximum, bulb 207 and bulb cavity 205 can be positioned at a maximum place and loop 209 is positioned at another maximum place.By loop 209 and bulb 207 being placed on the maximum place of electric field, the energy of huge amount is transmitted respectively and is ended.Bulb cavity 205 is concave shape in the body of waveguide 203.
As shown in Fig. 2 B, the body of waveguide 223 major part from the body of waveguide 203 alternatively is outwards outstanding to protrude shape, to form bulb cavity 225.As shown in Fig. 2 A, Fig. 2 B, bulb 227 is preferably relatively located with loop 221.Yet, in waveguide 203, providing under the situation of more than electric field maximum, bulb 207,227 can be positioned in the plane different with the plane of loop 209,221.
Get back to Fig. 1, the outer surface of waveguide 103 (except those surfaces that form bulb cavity 105) preferably is coated with thin metal coating 119, with microwave reflection.The level of the energy that is comprised in the mass reflex decision waveguide 103 of coating 119.The energy that can be stored in the waveguide 103 is many more, and the gross efficiency of lamp 101 is just high more.Coating 119 also preferably suppresses the easily radiation leakage of dissipation.Usually, coating 119 is preferably significantly eliminated any spuious microwave field.
By making cavity 105, can weaken microwave leakage significantly from bulb cavity 105 preferably significantly less than the microwave wavelength that is used for making lamp 101 work.For example, the cornerwise length of window is preferably significantly less than half of employed microwave wavelength (in free space).
Bulb 107 is arranged in the bulb cavity 105, and preferably includes outer wall 109 and window 111.In a preferred implementation, the cavity wall of the body of waveguide 103 is as the outer wall of bulb 107.The parts of bulb 107 preferably comprise one or more dielectric materials, such as pottery and sapphire.In one embodiment, the pottery in the bulb is identical with employed material in the waveguide 103.Dielectric material is preferred for bulb 107, this be because bulb 107 preferably by the dielectric body of waveguide 103 around, and dielectric material helps to guarantee effective coupling of the gas filler in microwave energy and the bulb 107.
Outer wall 109 preferably utilizes sealer 113 to be coupled to window 111, thereby limits the bulb shell 127 of air inclusion filler and luminous element, and gas filler comprises that plasma forms gas.Plasma forms gas and is preferably the inert gas that can form plasma.Luminous element is preferably in the prior art any or multiple metal halide at present known multiple element or the compound (such as sulphur, selenium, contain sulphur or selenium compound) (such as indium bromide (InBr
3)) the steam of any formation.
In order to help that gas filler is limited in the bulb 107, sealer 113 preferably includes vacuum seal.Outer wall 109 preferably comprises aluminium oxide, because the white colour of aluminium oxide, temperature stability, low porosity and thermal coefficient of expansion.Yet, one or more the other materials that provides generally in these character can also be provided.Outer wall 109 also preferably has such profile: its light with maximum reflects cavity 105 by window 111.For example, outer wall 109 can have parabolic profile, reflects away by window 111 with the light that will produce in the bulb 107.Yet, also can use to help other outer wall profile or configurations that light is guided away by window 111.
Window 111 preferably includes and is used for light transmissive sapphire, and because sapphire thermal coefficient of expansion and aluminium oxide coupling are good.The material that other can be had similar transmitance and thermal coefficient of expansion is used for window 111.Replace in the execution mode one, window 111 can comprise the lens of the light that collection is launched.
As above mentioned, in the course of the work, bulb 107 may reach up to about 1000 degrees centigrade or low slightly temperature.In this case, in one embodiment, waveguide 103 is as the radiator of bulb 107.Bring out stress by heat load and heat on each parts that reduce DWIPL 101, increase and surpassed the life-span of typical electrodeless lamp the useful life of DWIPL 101 generally.Preferably, by radiating fin 125 being arranged in the external surface peripheral of waveguide 103, can obtain to dispel the heat efficiently, as shown in fig. 1.In the execution mode shown in Fig. 2 B, because cavity 225 extends the major part away from the body of waveguide 223, advantageously, by fin 222 being arranged to more near bulb 227, DWIPL 220 can be used to remove more efficiently heat.
In another embodiment, the body of waveguide 103 comprises dielectric, and such as titanate, this dielectric is at high temperature unstable usually.In this embodiment, preferably, by between the body of waveguide 103 and bulb 107, the thermodynamic barrier layer being set, the heat that is produced in the waveguide 103 shielding bulbs 107.Replace in the execution mode at one, outer wall 109 since comprise low heat conductivity material (such as NZP, its as sodium zirconium phosphate and known) and as the thermodynamic barrier layer.Also can adopt other suitable materials to be used as the thermodynamic barrier layer.
Fig. 3 A and Fig. 3 B show the replacement execution mode of DWIPL 300, and wherein, vacuum gap is as the thermodynamic barrier layer.As shown in Fig. 3 A, the bulb 313 of DWIPL 300 is arranged in the bulb cavity 315, and separate a gap 317 with waveguide 311, preferably, the thickness in gap changes according to the microwave propagation feature and the strength of materials of the material of body that is used for waveguide 311 and bulb 313.Gap 317 is preferably vacuum, minimizes the heat transmission between bulb 313 and the waveguide 311.
Fig. 3 B shows the enlarged drawing of bulb 313, bulb cavity 315 and the vacuum gap 317 of DWIPL 300.The border of vacuum gap 317 is formed by waveguide 311, bulb supporter 319 and bulb 313.Bulb supporter 319 can be sealed to waveguide 311, and supporter 319 extends above the edge of bulb cavity 315 and comprises the material that preferably has high-termal conductivity (such as aluminium oxide), to help from bulb 313 dissipation heats.By with reference to following Fig. 7, Fig. 8 and Fig. 9, can find the more details of this equipment.
Fig. 7 shows the sectional view of traditional bulb supporting component.This supporting component comprises the supporting construction of being made by dielectric material.This supporting construction comprises the cavity that is used to hold bulb.Bulb remains on appropriate position in the cavity by extend into protuberance the cavity from supporting construction, and contacts along the circumference of bulb.Protuberance extends supporting construction with the angle of 90 degree.Because protuberance extends with the angle of 90 degree, therefore in supporting construction, produced big electric field.This increase of electric field in the invention of prior art has been shown and apart from the relation between the distance of protuberance among Fig. 9.The increase of electric field causes thereupon comprising that the resonance frequency of the resonance structure of supporting component increases.The increase of resonance frequency and then cause device drives to the amount of the required radio-frequency (RF) energy of resonance frequency is increased.The increase of power consumption has decreased the lumens/watt feature of lamp apparatus, thereby makes the efficient step-down of lamp.
Fig. 8 shows the sectional view of bulb supporting component of the present utility model.As prior art, this supporting component comprises the supporting construction of being made by dielectric material, and is formed on the cavity that is used to hold bulb in the supporting construction.Bulb is by remaining on from the extended protuberance of supporting construction in the cavity and contacting along the circumference of bulb.This protuberance is with of the prior art different, and it extends along a curve rather than with an angle of 90 degrees degree.Owing to use crooked protuberance, can not produce big electric field in the supporting construction.Owing to reduced electric field, comprised that the resonance frequency of the resonance structure of supporting construction reduces by supporting construction.Because reduced the resonance frequency of resonance structure, available lower radio-frequency (RF) energy level drives lamp.Lower radio-frequency driven energy level and then increased the lumens/watt feature of lamp apparatus has improved efficient thereupon.
Be embedded with a turnover sealer (access seal) 321 in the supporter 319, be used in gap 317, setting up vacuum when putting in place in bulb 313 arrangements.Preferably, bulb 313 support by bulb supporter 319 and vacuum seal to this bulb supporter.In case in gap 317, set up vacuum, then preferably, substantially reduced the heat transmission between bulb 313 and the waveguide 311.
So far the execution mode of described DWIPL is preferably with the microwave frequency work in the 0.5-10GHz scope.Operating frequency preferably excites one or more modes of resonance of being supported by the size of waveguide and shape, thereby sets up one or more electric field maximum in waveguide.When as resonant cavity, at least one gravel size decision ground of waveguide is the integral multiple of half-wavelength.
Fig. 4 A to Fig. 4 C shows three replacement execution modes with the DWIPL 410,420,430 of different mode of resonance work.Fig. 4 A shows the DWIPL410 with the work of first mode of resonance 411, and wherein the length of an axle of the waveguide 417 of rectangular prism shape is half of wavelength of employed microwave energy.Fig. 4 B shows the DWIPL 420 with mode of resonance 421 work, and wherein the length of an axle of the waveguide 427 of rectangular prism shape equals a wavelength of employed microwave energy.Fig. 4 C shows the DWIPL 430 with mode of resonance 431 work, wherein the length of an axle of the waveguide 437 of rectangular prism shape be employed microwave energy wavelength 3/2.
In DWIPL that in Fig. 4 A to Fig. 4 C, describes and each in the associative mode, and for DWIPL with arbitrarily higher pattern work, preferably, bulb cavity 415,425,435 and loop 413,423,433,434 are positioned at the position that electric field is in work maximum with respect to waveguide 417,427,437.But bulb cavity and loop needn't be positioned at same plane.
Fig. 4 C shows another execution mode of DWIPL 430, wherein uses 433,434 pairs of waveguide 437 supplying energies of two loops.These two loops 433,434 can be coupled to single microwave source or a plurality of microwave source (not shown).
Fig. 4 D shows another execution mode, and wherein single energy loop 443 is supplied to energy in the waveguide 447 with a plurality of bulb cavitys 445,446, and each bulb cavity is positioned at the position that electric field is in maximum with respect to waveguide 447.
Fig. 5 A to Fig. 5 C shows the DWIPL 510,520,530 of the waveguide 517,527,537 with cylindrical prism shape.In the execution mode shown in Fig. 5 A to Fig. 5 C, the height of cylinder is preferably less than its diameter, and diameter preferably approaches can be at the integral multiple of the lowest class half-wavelength of the energy of waveguide 517,527,537 interior resonances.Cylinder is carried out this size restrictions make that the height of lowest resonance pattern and cylinder is irrelevant.Thereby, the basic schema of the energy in diameter control (dictate) waveguide 517,527,537 of cylinder.Therefore, can require (such as size and heat radiation) to optimize the height of cylinder at other.In Fig. 5 A, loop 513 preferably is positioned to just relative with bulb cavity 515, and preferably excites zero level Bezier pattern 511.
In the waveguide of cylindrical prism shape, also can excite other patterns.For example, Fig. 5 B shows the DWIPL 520 with a mode of resonance job, and wherein the diameter of cylinder 527 is preferably near a wavelength of employed microwave energy.
As another example, Fig. 5 C shows the DWIPL 530 with a mode of resonance job, and wherein the diameter of cylinder 537 is preferably near 3/2 of the wavelength of employed microwave energy.In addition, Fig. 5 C shows the execution mode of DWIPL 530, wherein uses waveguide 537 supplying energies of two loops 533,534 to cylindrical shape.Other execution modes for DWIPL, in the DWIPL of the waveguide with cylindrical shape, bulb cavity 515,525,535 and loop 513,523,533,534 preferably are positioned at the position that electric field is in maximum with respect to waveguide 517,527,537.
The working medium waveguide has several tangible advantages.The first, as mentioned above, waveguide can be with the heat that is produced in the bulb of helping to dissipate.The second, in dielectric waveguide, can realize than the higher power density of possible power density in the employed plasma lamp with air cavity in the present prior art.According to the dielectric constant of the material that is used for waveguide, the energy density of dielectric waveguide is greater than the energy density of air chamber bulk plasmon lamp.
Return the DWIPL 101 with reference to figure 1, the high resonant energy corresponding to the high Q value that is used for waveguide (wherein Q is an operating frequency and the ratio of the band width of resonance) in the waveguide 103 makes the easier dissipation of microwave energy leak in the bulb cavity 105.High-leakage in the bulb cavity 105 causes the quasi-static breakdown of the inert gas in the shell 127, thereby produces first free electron.The oscillation energy estimation (scale) of described free electron is I λ
2, wherein I is the intensity of circulation of microwave energy, and λ is the wavelength of energy.Therefore, microwave energy is high more, and the oscillation energy of free electron is big more.By making oscillation energy greater than the ionisation of gas electromotive force, electronics-neutron collision has produced plasma density accumulation efficiently.
In case form the energy that plasma and absorption bring in DWIPL, then the Q value of waveguide can descend owing to the conduction and the absorbent properties of plasma.The decline of Q value is because the change of the impedance of waveguide generally.After plasma formed, the existence of cavity ionic medium body made that the bulb cavity is absorbefacient for resonant energy, had therefore changed the overall impedance of waveguide.The change of this impedance is the effectively reducing of mass reflex of waveguide.Therefore, be matched to the reflectivity that reduces near waveguide, or even after plasma forms, also can obtain fully high Q value, to keep plasma by reflectivity with loop.Therefore, can realize turning back to low relatively clean reflection in the energy source.
The most of energy that is absorbed by plasma finally shows as heat, makes that the temperature of lamp may be near 1000 degrees centigrade or low slightly temperature.When waveguide also was used as radiator, as previously mentioned, the size of waveguide can change owing to its thermal coefficient of expansion.In this case, when waveguide is expanded, change and lose resonance in the microwave frequency of waveguide interior resonance.In order to keep resonance, preferably, at least one size of waveguide equals the integral multiple of the half-wavelength of the microwave frequency that microwave source produces.
A preferred implementation that compensates the DWIPL that this size changes adopts the waveguide that comprises such dielectric material, this dielectric material for the temperature coefficient of refractive index be substantially equal to its for the temperature coefficient of thermal expansion but symbol in contrast.Use this material, offset change of refractive because the size that causes of heat changes, thus the possibility minimum that the mode of resonance of cavity is interfered.This material comprises titanate.Compensation forms tapering in a predefined manner gradually because second execution mode that the size that heat causes changes is included in the wall that physically makes waveguide.
In another preferred embodiment, as being schematically shown among Fig. 6, DWIPL 610 can work with dielectric resonance oscillator pattern.In this pattern, the first microwave loop 613 and the second microwave loop 615 are coupled between dielectric waveguide 611 and the source of microwave energy 617, the Any shape that this dielectric waveguide is described before can being.Energy source 617 is preferably wide band, has the output of high-gain and high power and can drive to send plasma.
In other embodiments, first loop 613 can come work according to top description usually.Second loop 615 can be surveyed waveguide 611, with to field (comprise wherein comprised amplitude and the phase information) sampling that exists and will sample and offer the input of energy source 617 or amplifier as feedback.When surveying waveguide 611, second loop 615 also preferably is used for filtering out the spurious frequency in the waveguide 611, only stays resonance frequency.
In this embodiment, first loop 613, second loop 615 and bulb cavity 619 all preferably are positioned at the position that electric field is in maximum with respect to waveguide 611.By using second loop 615, the resonant energy that energy source 617 amplifies in the waveguide 611.Thereby its output frequency is regulated to keep one or more modes of resonance in the waveguide 611 in source 617.Therefore, this complete construction has formed resonant oscillator.By this way, can realize forming owing to plasma and the frequency shifts that the heat change of size causes and the automatic compensation of dielectric constant.
Dielectric resonance oscillator pattern also makes DWIPL 610 can have after closing the ability of restarting (re-strike) immediately.As previously mentioned, the thermal expansion that may cause owing to the heat that is produced in the course of work of the resonance frequency of waveguide 611 or the variation of dielectric constant change.When DWIPL610 closed, heat dissipated lentamente, caused the instantaneous change of the resonance frequency of waveguide 611.
Yet as noted above, in the resonant oscillator pattern, energy source 617 is the change of resonance frequency of compensation waveguide 611 automatically.Therefore, regardless of the startup feature of waveguide 611, and suppose that energy source 617 has the bandwidth of requirement, then energy source 617 will compensate automatically, to realize resonance in waveguide 611.Energy source offers DWIPL with the plasma formation frequency of optimum with power immediately.
Although illustrated and described execution mode of the present utility model and advantage, it will be apparent for a person skilled in the art that can have many changes under the situation that does not deviate from principle of the present utility model.Therefore, the utility model is not subjected to limit except extramental other of claims.