HK1008759A1 - Process for operating an incoherently emitting radiation source - Google Patents

Description

The invention relates to a process for operating an incoherently emitting radiation source as defined in the general term of claim 1. The mechanism for generating radiation is a discharge produced within a discharge vessel, with a dielectric layer placed between at least one electrode and the discharge, which is why this type of discharge is also called silent or dielectrically obstructed discharge or barrier discharge.

The excitation of such discharges is usually by means of an alternating voltage, as for example disclosed in disclosures DE-A-40 22 279 and DE-A-42 03 594 and US-A-5 117 160.

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EP-A-0 302 748 describes a lamp-like display unit with an electrically isolated electrode, which is operated by means of dielectrically inhibited discharge. To ignite the discharge, a high-frequency voltage with peak values in the range of 300 V to 6 kV is generated between the lamp electrodes. The electrodes of the lamp-like display unit are connected to the secondary winding of a transformer. The primary winding of the transformer is connected to a power supply via a switching transistor. The base of the switching transistor is controlled by a pulse generator, which delivers repetitive unipolar rectangular pulses with a repetition frequency between 0.5 kHz and 20 kHz.

The purpose of the invention is to improve substantially the efficiency of the desired radiation generation.

This task is solved in accordance with the invention by the characteristics of claim 1, and further advantages of the invention are explained in the sub-claims.

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In the case of a lighting system, the voltage is usually equal to or equal to the voltage of the light source, but the number of voltage pulses is not limited, but in special cases it is possible to use a series of regularly changing voltage pulses, and the pulse sequence may be completely irregular (for example, in the case of power lighting, where several pulses are combined into a beam that produces a light effect visible to the human eye).

During the pulse times TPn, a voltage pulse UPn(t) is applied between the electrodes, coupled with the active power. (a) unipolar forms, i.e. the voltages do not change their character during the pulse times TPn, including trapezoidal, triangular, arc-like voltage pulses, especially parabolic and sine wave pulses, where both positive and negative values are suitable (see Figure 6a, which shows only negative values as an example);Err1:Expecting ',' delimiter: line 1 column 212 (char 211)In addition, a large number of other forms are conceivable. In particular, electrical signals in practice always have finite rise and fall times, over and under oscillations, which is not shown in Figures 6a to c.

The voltage form during the dead-times T0n is required to be set at U0n(t) so that no power coupling is essentially achieved. Accordingly, low voltage values less than the ignition voltage may last longer, possibly the entire dead-time T0n. It is not excluded that short-term, i.e. much shorter than the pulse time TPn, voltage peaks may also occur during the dead-times.

Typical absolute values for UPn are a few kV. U0n is preferably close to 0 V. The values of TPn and T0n are typically in the μs range, with TPn usually being significantly shorter than T0n.

The discharge operating mode of the invention is essentially achieved by an appropriate choice of the excitation parameters TPn, T0n and the voltage amplitude UPn, which are adjusted to each other in a way that is suitable for particularly efficient operation.

In the individual case, the values to be selected for the three excitation parameters TPn, T0n and UPn (t) depend on the discharge geometry, the type of gas filling and gas pressure, the electrode configuration and the type and thickness of the dielectric layer.

The rates of shock processes in the discharge and consequently also of radiation production at given lamp fillings are essentially determined by the electron density and energy distribution of the electrons. e operating procedure of the invention makes it possible to optimally adjust these time-dependent quantities by means of the appropriate choice of TPn, T0n and the voltage amplitude UPn or the pulseform for radiation production.

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A remarkable advantage of the invention lies in the particular stability of the individual discharge structure in relation to a change in the electrical power density coupled to the discharge vessel. If the amplitude UPn of the voltage pulse is increased, the individual discharge structures do not change their basic shape. After a threshold is exceeded, other similar structures are formed from one of the discharge structures. An increase in the coupled electrical power by increasing the amplitude of the voltage pulse essentially leads to an increase in the number of the individual discharge structures described, while the quality of these structures, in particular their appearance and their efficient radiation properties, remains unchanged.

This behaviour makes it possible for the first time to increase the electrical power coupled to a given discharge volume in a meaningful way by using more than two electrodes that make optimal use of the discharge volume. For example, an inner electrode placed centrally within the discharge vessel can be faced with several outer electrodes symmetrically placed on the outer wall of the discharge vessel.

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From this phenomenology a general rule can be derived for attaining the values for UPn (t), Tp (n) and Tn (t) appropriate for the operation of the invention. After the discharge has been ignited, UPn (t), Tp (n) and Tn (t) must be chosen so that the desired electrical power is coupled in the operation of the invention, i.e. the discharge structures described above are visible. Surprisingly, it has been found that it is precisely in the presence of these discharge structures that the electron density and the energy distribution function of the electrons assume values which minimize the losses.

Each of the above three operating parameters affects both the temporal and spatial structure of the charge carrier densities and the energy distribution function of the electrons.

Typical values for the amplitude UPn of the voltage pulse are in the range of about 0.01 to 2 V per cm stroke width and Pascal fill pressure, the pulse times TPn and the dead times T0n are in the range of about 1 ns to 50 μs and about 500 ns to 1 ms respectively. For the operating mode of the invention, the operating pressure is advantageously between 100 Pa and 3 MPa.

For reasons of electrical safety, the external electrodes are preferably connected to mass potential and the internal electrode to the high voltage. This allows a wide range of contact protection of voltage-conducting parts. The discharge vessel, including electrodes, can also be arranged inside a casing piston. This provides contact protection even if the external electrode is not connected to mass potential (is).

For the unilateral dielectrically impeded discharge - i.e. at least one dielectrically unimpeded electrode is located inside the discharge vessel, in the gas chamber - it is also imperative that this inner electrode at the beginning of the pulse time has a negative polarity to the dielectrically impeded electrode (inside or outside the discharge vessel) (apart from possible positive needle-shaped and power coupling-related pre-pulses), after which the polarity may change during the pulse time.

The method of operation is also suitable for discharges with two-sided dielectric impedance (all electrodes are separated from the discharge by a dielectric, which may be the discharge vessel itself) without the need to change the principle or lose its beneficial effect.

In principle, the electrodes can be all located outside the gas chamber, e.g. on the outer surface of the discharge vessel, or a certain number of them outside and a certain number inside, as well as all within the discharge vessel, in the gas chamber.

In particular, in the case of aggressive media inside the discharge vessel, it is advantageous if none of the electrodes is in direct contact with the medium, as this can effectively prevent corrosion of the inner electrode.

The invention does not require large area electrodes. The radiation shading by the electrodes is very low. For dielectrically impeded electrodes, the ratio of the dielectric surface in contact with the dielectric surface to the radius of this electrode surface is preferably as small as possible. In a particularly preferred embodiment, the dielectrically impeded electrodes are made as narrow strips applied to the outer wall of the discharge vessel.

The single or double-sided discharge allows the realization of a wide variety of possible discharge vessel geometries, in particular all those which are revealed in the case of conventionally operated dielectrically-discharged discharges, e.g. in EP-A-0 385 205, EP-A-0 312 732, EP-A-0 482 230, EP-A-0 363 832, EP-A-0 458 140, EP-A-0 449 018 and EP-A-0 489 184.

In small discharge vessels, the electrodes should preferably be arranged so that the distance between the corresponding anodes and cathodes is as large as possible. For example, for cylindrical discharge vessels with small cross-section, the inner electrode is preferably arranged ascentrically within the discharge vessel and the outer electrode is diametrically opposite to the outer wall. The extension of the discharge path can be further supported by the arrangement of the electrodes.

For larger cross-sections, the inner electrode is preferably placed centrally within the discharge vessel, with the advantage of having several outer electrodes fixed to the outer wall, symmetrically distributed over the perimeter.

The shape of the discharge vessel is not in principle mandatory. Depending on the application, the vessel walls must be made of materials which are transparent enough to provide the desired radiation - at least within an aperture. The dielectric barriers used are high voltage shock-resistant electrically insulating materials (dielectric), such as borosilicate glass - for example DURAN® (Fa. Schott) - quartz, Al2O3, MgF2, LiF, BaTiO3, etc. The type and thickness of the dielectric structure can influence the discharge structure. In particular, the dielectric structure is sufficiently thick to be formed by a suitable diode.

Err1:Expecting ',' delimiter: line 1 column 604 (char 603)a. Precious gases and mixtures thereof, mixtures of precious gases with halogens or halogen compounds, metal vapours and mixtures thereof, mixtures of precious gases with metal vapours, mixtures of precious gases with metal vapours and halogens or halogen compounds, and any combination or single of the following elements which may be added to the above-mentioned fillings: hydrogen, deuterium, oxygen, nitrogen, nitrogen oxides, carbon monoxide, carbon dioxide, sulphur, arsenic, selenium and phosphorus.In particular, the surfaces of the invention which are capable of producing highly efficient UV radiation in excitatory beverages, which are capable of producing a wide range of UV radiation, such as the photochemical field of 48-02A, are to be classified as the heat exchanger, as described in the patent.In particular, for the latter applications, it may be advantageous to place the discharge in the immediate vicinity of the medium to be irradiated, i.e. to avoid a hermetically sealed discharge vessel in order to avoid attenuation of the short-wave portion of the radiation through the vessel walls. In particular, in the production of UV and VUV radiation, another decisive advantage is the high UV emission obtained by the operation according to the invention: unlike UV and VUV lenses, comparable to the constant density according to the technique, the discharge can be avoided by a water cooling.by converting UV radiation into the visible part of the electromagnetic spectrum by means of suitable fluorescent materials.

The invention has other advantages: no external current limitation is required, the lamp is dimmable, several lamps can be operated in parallel on a single voltage supply and a high efficiency of radiation generation is achieved at the same time as the power density required in lighting technology.

A fluorescent coating can be used on both low pressure and high pressure lamps, using known fluorescent materials or mixtures. A combination of blue, green and red light emitting fluorescent lamps has proven particularly effective. A suitable blue fluorescent material is, in particular, the divalent Europium-activated barium magnesium sulphate (Mg10O17: Eu2+Si): three active components of the compound are EPO3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3O3: B3: B3O3: B3O3: B3O3: B3: B3O3: B3O3: B3: B3O3: B3O3: B3O3: B3 B3O3: B3 B3O3: B3 B3 B3O3: B3 B3 B3 B3O3: B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B3 B

For lamps of a warm colour, the proportion of the blue component may be reduced or eliminated, as is usual with fluorescent lamps.

For lamps with special colour reproduction characteristics, components emitting in the blue-green spectral range, e.g. fluorescent materials activated with bivalent Europium, are preferred for this application.

The invention is particularly important in the field of fluorescent lamps. For the first time, mercury has been eliminated from the filling and the internal UV efficiency has been achieved at levels comparable to conventional fluorescent lamps. Compared with conventional fluorescent lamps, this has the following additional advantages: a smooth cold start is possible without the influence of ambient temperature on the light flow and without the occurrence of bulb heating. Furthermore, no electrodes (e.g. bulb cathodes with emitters), including heavy metals and radioactive bails (light discharge) are required to operate.

The invention is explained in more detail below by means of some examples of embodiments. Fig. 1the partially cut longitudinal view of an embodiment of a discharge lamp in the form of a rod, which can be operated according to the new method,Fig. 2a cross-section along A-A of the discharge lamp shown in Fig. 1,Fig. 2b the cross-section of another embodiment of a discharge lamp,Fig. 2c the cross-section of another embodiment of a discharge lamp,Fig. 3a schematic representation of the preferred form of the voltage between cathode and anode of the lamp shown in Fig. 1, which prevents the discharge of the discharge,Fig. 3a geometrical representation used for the discharge of the discharge, which can only be used for the design of a discharge device which is capable of eliminating the discharge of the discharge.Fig. 4b, a partially cut out view of another embodiment of the invention of a discharge lamp in the form of a surface beam which can be operated by the new method,Fig. 4b, the cross-section of the discharge lamp shown in Fig. 4a,Fig. 5adie side view of another embodiment of the invention of a discharge lamp in the form of a conventional lamp with Edison screw base which can be operated by the new method,Fig. 5b, the cross-section along A-A of the discharge lamp shown in Fig. 5a,Fig. 6b, a more detailed graphic representation of the invention of a unipolar spinning device using a negative UP voltage (Fig. 6b), a more detailed illustration of the invention using a combination of UP voltage and negative UP voltage (Fig. 6b), a more detailed illustration of the invention of a bipolar spinning device using a positive UP voltage (Fig. 6b), a more detailed illustration of the invention of a bipolar spinning device using a positive UP voltage (Fig. 6b), a more detailed illustration of the invention of the invention.6a and 6b,Fig. 7 measured time courses of voltage U ((t), current I ((t) and power P ((t) = U ((t).I ((t) according to the invention mode (173 hPa Xe, pulse frequency: 25 kHz),Fig. 8 depiction according to Figure 8 but time axis changed,Fig. 9a,b photographic representations of discharge structures according to the invention,Fig. 10a-d photographic representations of the transition to undesirable discharge structures.

The present invention is illustrated in a particularly simple embodiment by means of Fig. 1 showing a medium pressure discharge lamp 1 in the form of a stainless steel rod with a length of 2.2 mm, partially cut and filled with xenon at a pressure of 200 hPa. Inside the cylindrical discharge vessel 2 of glass, defining a longitudinal axis, with a length of 590 mm, a diameter of 24 mm and a wall thickness of 0.8 mm, there is an axis-parallel inner electrode 3 in the form of a stainless steel rod with a diameter of 2.2 mm. Outside the discharge vessel 2 there is an outer electrode 2 connected by two 2 4a conductors, connected by eight 4a conductors, arranged in a parallel plane. The discharge conductor is connected by a single contacting ring, which can be connected by means of two 14 mm diameter conductors. The outer conductor is connected by a single contacting ring, which can be connected by means of two 14 mm diameter conductors. The outer conductor is connected by two 4a conductors, which are arranged in a parallel plane. The outer conductor is connected by four four four four four electrical conductors, which can be connected by means of a single contacting ring, and the inner conductor can be connected by means of a single contacting ring.

In one variant of this embodiment, the discharge vessel in the metal ring area has an enlarged diameter, e.g. in the form of a wick, which prevents the formation of disturbing parasitic discharges in this area. In a particularly preferred variant of the above embodiment, the axis-shaped in-electrode is rigidly connected to the first tube fuse only at one end. The other end is loose in a cylindrical, centrally axially attached to the second tube fuse - similar to a ball-and-socket case. This has the advantage that the inner electrode cannot be disconnected when heated, e.g. at high electrical power, and can therefore be deflected in the opposite direction.

The inner electrode 3 is placed centrally, with two electrodes 4a,b, symmetrically distributed on the outer wall of the discharge vessel 2, on the outer wall.

The basic structure of the voltage supply required for the operation of the discharge lamp 1 in accordance with the invention is also schematically shown in Figure 1. The pulse train, i.e. the shape and duration of the voltage pulses and the duration of the deadlines, is generated in a pulse generator 10 and amplified by a subsequent power amplifier 11. The pulse train is schematically shown as it is attached to the inner electrode 3. The single-voltage transformer 12 transforms the signal from the power amplifier 11 to the required high voltage. The lamp is operated at pulsed voltage equation. This is a negative pulse response time according to Figure 3a. The following pulses are applied:

The interior of the discharge vessel is additionally coated with a fluorescent layer 6. The UV radiation emitted in this example by the discharge is converted into the visible range of the optical spectrum, so that the lamp is particularly suitable for lighting purposes. It is a three-band fluorescent with the following components: the blue component is BaMgAl10O17: Eu2+, the green component is Y2SiO5:Tb and the red component is Y2O3:Eu3+. This results in a light output of 37 lm/W. The respective color reflection properties were achieved at a temperature of 4000 K. The maximum reflection time was approximately 80 μs. The fluorescent value of the medium VUVA is defined by the value of the maximum reflection time between 1 μs and 10 μs. The maximum reflection time of the lamp is between 10 μs and 18 μs. The maximum reflection time is defined as the maximum value of the medium VUVA (T.V.V.V.V.) at the maximum operating temperature of the lamp (T.V.V.) and the maximum reflection time is between 1 μs and 27 μs. The maximum reflection time is between 1 μs and 18 μs. The maximum reflection time is defined as the maximum reflection time of the lamp (T.V.V.V.V.V.V.V.) at the maximum operating temperature of the lamp is between 1 μs and 1 μs.V.V.V.V.T.T.T. (T.V.) and the maximum reflection time of the lamp is between 1 μs.V.V.T.V.T. (T.V.) and the maximum reflection time of the lamp is between 1 μs.V.V.T.V.T. and the maximum operating time is between 1 μs.T.T. and the maximum operating time of the lamp is between 1 μs.T.T. and the following two p.T.T.T.T. Other Tabelle:

p(Xe) in hPa	p(Ne) in hPa	Up in kV	up in V/cm Pa
100	-	2,41	0,200	55
133	-	2,39	0,150	60
200	-	2,95	0,123	65
200	733	3,50	0,031	60

Another example is shown in Fig. 2b. The inner electrode 3' is oriented ascentrically near the inner wall and parallel to the longitudinal axis of the cylindrical discharge vessel 2, with the outer electrode 4' diametrically opposite fixed to the outer wall. This arrangement is particularly advantageous for cylindrical discharge vessels with a small cross-section, since on the one hand the discharge extends diametrically within the discharge vessel and on the other hand the outer wall is covered only with a guide strip as the outer electrode, i.e. the radiating surface is not reduced by a second outer electrode.

In another example in Fig. 2c, as in Fig. 2a, the inner electrode 3 is placed centrally within the discharge vessel 2 and four outer electrodes 4'a,4'b,4'd,4'e are placed symmetrically around the outer wall of the discharge vessel 2 so that this configuration is particularly suitable for large-diameter discharge vessels with a large mantle area.

In another embodiment, the inner wall of the headlamp in Figure 1 has a UV or VUV reflective coating, e.g. MgF2, Al2O3 or CaF2, instead of the fluorescent coating 6, with only a narrow, preferably lamp-axis-parallel strip of the inner wall uncoated. The outer electrodes are arranged so that the UV or VUV radiation can pass through this strip unhindered. This embodiment is particularly suitable for efficient VUV reflection from extended objects, e.g. for exposure in the outer lens.

Figure 3a shows a schematic of the preferred pulse shape of the voltage between the inner electrode (cathode) and the outer electrode (anode) according to the invention for the unilateral dielectrically inhibited discharge.

Figure 3b shows a diagram of a pulse shape whose polarity changes from pulse to pulse, suitable only for two-sided dielectrically inhibited discharge, the first pulse being capable of starting at any polarity.

Figure 4a shows the view and Figure 4b the cross-section of another embodiment of a dielectrically inhibited discharge lamp which can be operated according to the new method: it is a surface lamp having an upper beam area 7a and a parallel lower beam area 7b, to which the inner electrodes 3 and 4 are vertically oriented and are arranged alternately so as to form a large number of parallel discharge chambers 8 . Each of the adjacent outer and inner electrodes is blocked by a single discharge layer and a discharge layer 8 . The discharge area is only separated by a layer of discharge. The combination of the two is only possible by means of a single discharge layer.

Figure 5a shows the side view and Figure 5b shows the cross section of another embodiment of a discharge lamp. It is similar in its external form to conventional Edison-socket lamps 9 and can be operated according to the new method. Inside the discharge vessel 2 a longitudinal inner electrode 3 is placed centrally, the cross section of which corresponds to the shape of a symmetrical cross. On the outer wall of the discharge vessel 2 four external electrodes 4'a,4'bnene,4'd,4'e are mounted so that they face the four longitudinal sides of the inner electrode 3 and the discharge structures are thus essentially in two planes, which intersect each other and cut along the perpendicular axis of the lamp.

In another preferred variant of the above embodiment, the inner electrode consists of a stainless steel rod with a circular cross-section and a diameter of 2 mm. It is arranged centrally axially within a circular cylindrical discharge vessel of 0.7 mm thick glass. The discharge vessel has a diameter of about 50 mm and at the socket end has a pump tip into which the socket-away end of the inner electrode is inserted. The inside of the discharge vessel is filled with xenon at a pressure of 173 hPa. The outer electrodes are distributed by twelve 1 cm wide and 8 cm long conductive bands, which are equally distributed along the axis of discharge and are arranged in a uniform manner along the outer side of the discharge.The outer electrodes are electrically connected in the socket area by means of a conductive silver strip mounted in a ring on the outer wall. The inner wall of the discharge vessel is coated with a fluorescent layer 6. It is a three-band fluorescent with the blue component BaMg10O17: Eu2+, the green component LaPO4: (Tb3+, Ce3+) and the red component (Gd,YBO3: Eu3+. This results in a light output of 40 lm/W. The color temperature is 4000 K and the color output according to the color standard CIE has the coordinates x = 0.38 and y = 0.377.The maximum value of the voltage of the inner electrode with respect to the outer electrodes is about -4 kV. The pulse duration (duration at half the maximum value) and the dead time are about 1.2 μs or about 37.5 μs. In Figure 8 four pre-pulses of much smaller amplitude are also visible before the second main pulse of the voltage flow U (t) as shown by the corresponding currents I (t) and P (t) during this pre-pulse no current flows and therefore no electrical power is coupled to the gas.

In another variant of the above embodiment, the discharge vessel is made of a transparent material for UV or VUV radiation, such as SUPRASIL® quartz glass (Fa. Heraeus Quartzschmelze GmbH). It is suitable as a VUV emitter, e.g. in photochemistry. In another variant, the inner electrode is coated with glass. This is particularly advantageous when using aggressive media, e.g. noble gas halides, as this prevents corrosion of the inner electrode.

Figures 9a, b show photographic representations of the discharge structures of the invention produced by unipolar voltage pulses. Figure 9a shows a dielectrically impeded discharge on two sides. A circular tube-shaped glass discharge vessel is mounted on its outer wall with two diametrically opposed axially arranged stripe-shaped outer electrodes. Inside the discharge vessel and in the connection plane of the two outer electrodes, the Δ-like discharge structures are arranged in a row. The narrow foot points of the Δ-like discharge structures each start at the cathodic inlet and extend to the outer wall of the discharge vessel, which is separated from the outer wall by an additional discharge discharge, as shown in Figure 9a.The structure of the internal electrode is a metal rod-shaped inner electrode. It acts as a cathode and is centrally axially arranged within the discharge vessel. From the surface of the inner electrode, the individual A-like discharge structures extend to one of the two outer electrodes. In particular, it is clearly visible in Figure 9b that these structures essentially diffuse uniformly. Only at their narrow cathodic endpoints do they each have a very small percentage of luminous area.

This variety of similar structures is in striking contrast to the photographic representations in Figures 10a to 10d. They show in this order the gradual transition to undesirable discharge structures. In Figure 10a - the discharge arrangement corresponds to that in Figure 9b - some Δ-like discharge structures are still visible. In the lower left-hand area of the discharge arrangement, a structure resembling a Y has already formed. In the upper left-hand area of the representation - the middle of the image - something has already formed a threadlike upper luminous structure at the expense of some of the originally right-hand adjacent A-like discharge structures.The discharge area shown in Figure 10b shows a further reduction in UV efficiency compared to Figure 10a. The number of structures originally present in this area has been further reduced. Figures 10c and 10d show a two-sided discharge (discharge order corresponding to the discharge order shown in Figure 9a) or a one-sided dielectrically impeded discharge. In both cases only a thread-like structure remains.The cathode is then connected to the cathode, and the cathode is connected to the cathode.

The invention is not limited to the embodiments given, in particular, individual features of different embodiments can be combined with each other in an appropriate manner.

Claims (23)

1. Method for operating an incoherently emitting radiation source, especially a discharge lamp (1), by means of dielectrically inhibited discharge, in which an at least partially transparent discharge vessel (2) of electrically nonconductive material is filled with a gas filling (5), in which at least two electrodes (3, 4) are fitted in the vicinity of the gas filling (5) and are connected by means of supply lines to an electrical power supply (10-12) and in which a dielectric layer is disposed between at least one electrode (4) and the gas filling (5), characterized in that the electrical power supply delivers a succession of voltage pulses between the electrodes (3, 4), the individual pulse n being characterized by a temporal progression of the voltage U_Pn(t) and duration T_Pn with values of the order of magnitude of approximately 1 ns to 50 µs and in each instance the pulse n being separated from its successor n+1 by a dead time of the duration T_On with values of the order of magnitude of approximately 500 ns to 1 ms and the voltage progression U_On(t), during the durations T_Pn the voltage progressions U_Pn(t) being selected so that during T_Pn predominantly electrical real power is coupled into the gas filling (5), whilst during the dead times T_On the voltage progressions U_On(t) are selected so that the gas filling (5) can return to a condition which resembles the condition prior to the respectively foregoing voltage pulse U_Pn(t), the quantities U_Pn(t), T_Pn, U_On(t) and T_On being coordinated with one another so that discharge structures of relatively low current densities arise between the electrodes (3, 4).
2. Method according to Claim 1, characterized in that the voltage progressions U_Pn(t) are unipolar, and in that the discharge in the unipolar case develops individual Δ-like discharge structures and in the case of alternating polarity of a bilaterally dielectrically inhibited discharge correspondingly in each instance a mirror-image superposition of two such discharge structures results, which resembles a , it also being possible for the spacings of these individual discharge structures to decrease in such a manner that in the limiting case the entire discharge plane emits in a type of "curtain"-like structure.
3. Method according to one or more of the preceding claims, characterized in that the durations T_On are selected so that the temporal mean value of the volume of an individual discharge structure becomes a maximum. Method
4. Method according to one or more of the preceding claims, characterized in that during the durations T_Pn for the voltage progressions U_Pn(t) between the electrodes (3, 4) values are selected which are coordinated with the reignition voltage of the discharge.
5. Method according to Claim 4, characterized in that the voltage progressions U_Pn(t) and U_On(t) and the durations T_Pn and T_On are coordinated with the filling pressure, the type of filling, the striking distance, the dielectrics and the electrode configuration.
6. Method according to Claim 5, characterized in that the voltage progressions U_Pn(t) are composed, directly or approximately, of one or more of the following basic forms: triangular, rectangular, trapezoidal, stepped, arcuate, parabolic, sinusoidal.
7. Method according to Claim 6, characterized in that during the durations T_Pn maximum values for the voltage pulses U_Pn(t) between the electrodes (3, 4) are selected which at least correspond to the reignition voltage plus the voltage drop caused by the dielectric.
8. Method according to Claim 7, characterized in that maximum values of the voltage pulses are in the range between 0.01 and 2 V per cm striking distance and per Pascal filling pressure.
9. Method according to one or more of the preceding claims, characterized in that the development of discharge structures of relatively low current densities is assisted by sufficient thicknesses of the dielectric layers and appropriately low relative dielectric constants.
10. Method according to Claim 1, characterized in that the voltage progression is periodic.
11. Method according to Claim 1, characterized in that at least in the case of one electrode the dielectric layer is formed by the wall of the discharge vessel (2).
12. Method according to Claim 1, characterized in that the ratio of the electrode area which is in contact with the dielectric to the periphery of this electrode area is as small as possible.
13. Method according to Claim 1, characterized in that in the case of the unilaterally dielectrically inhibited discharge the voltage progressions U_Pn(t) of the dielectrically uninhibited electrode(s) (3), measured against the dielectrically inhibited one(s) (4), begin during the injection of power with negative values - apart from any possible positive voltage peaks which are insignificant with respect to the injection of real power.
14. Method according to Claim 1, characterized in that in the case of the unilaterally dielectrically inhibited discharge the voltage amplitudes U_Pn(t) of the dielectrically uninhibited electrode(s) (3), measured against the dielectrically inhibited one(s) (4), are exclusively negative during the injection of power - apart from any possible positive voltage peaks which are insignificant with respect to the injection of real power.
15. Method according to Claim 1, characterized in that in the case of the use of a plurality of dielectrically inhibited electrodes unipolar or bipolar voltage pulses or voltage pulses of alternating polarity are applied between bilaterally dielectrically inhibited electrodes.
16. Method according to Claim 1, characterized in that in the case of the use of a plurality of dielectrically inhibited electrodes bipolar voltage pulses are applied between bilaterally dielectrically inhibited electrodes.
17. Method according to one or more of the preceding claims, characterized in that in the case of the use of one or more in particular bar-shaped or strip-shaped electrodes which are disposed in the discharge vessel (2), these are disposed centrally or non-centrally, it being possible for one or more of the electrodes to be jacketed with dielectric.
18. Method according to one or more of the preceding claims, especially Claim 1 or 12 or 17, characterized in that in the case of the use of one or more electrodes disposed outside the discharge vessel, these are designed to be strip-shaped.
19. Method according to Claim 1, characterized in that the discharge vessel (2) comprises a tube, in the longitudinal axis of which an inner electrode (3) is disposed and on the outer wall of which at least one outer electrode (4) is fitted.
20. Method according to Claim 1, characterized in that in that the discharge vessel (2) has a flat parallelepiped structure which is bounded by lateral surfaces and two covering surfaces (7a, 7b), through which the radiative emission essentially takes place, inner and outer electrodes (3) and (4) respectively being disposed perpendicular to the covering surfaces so that a multiplicity of parallel discharge chambers (8) is created, which chambers are disposed in a plane which is parallel to the radiative emission plane, i.e. the covering surfaces (7a, 7b) of the flat parallelepiped structure, the respectively adjacent electrodes (3, 4) at differing electrical potential being separated by a gas-filled discharge chamber (8) and a dielectric layer.
21. Method according to Claim 20, characterized in that the electrodes are separated from the gas-filled discharge space by dielectric layers.
22. Method according to Claim 1, characterized in that the discharge vessel is substantially cylindrical and is provided, at one end, with a base (9), a central bar-shaped inner electrode (3), which is preferably fixed on one side, being situated within the discharge vessel and at least one strip-shaped electrode (4'a, 4'b, 4'd, 4'e) being disposed on the outer wall of the discharge vessel.
23. Method according to one or more of the preceding claims, characterized in that the operating pressure of the gas filling (5) is in the range between 100 Pa and 3 MPa, especially more than approximately 1 kPa.