Electrodeless lamp

Abstract

An electrodeless lamp driven by a microwave generator is disclosed. The electrodeless lamp includes a first infill composed of mercury-free metal halide and provides a continuous full spectrum radiation including ultraviolet ray, visible light, and infrared ray. Thereby, the electrodeless lamp, which meets the standard of AM 1.5 G, has advantages of environmental friendliness, high efficacy lighting, long service life, and low light decay, and therefore, have become applicable in the field of solar simulators.

Claims

1. An electrodeless lamp driven by a microwave generator, comprising: an electromagnetic housing, which has a microwave-providing cavity; a bulb, which is positioned on the microwave-providing cavity of the electromagnetic housing by a lamp body; a conductive mesh, which surrounds the bulb; and a magnetron, which transmits the generated microwave to the microwave-providing cavity by a waveguide; wherein the bulb is filled with a sulfur free filler with mercury-free metal halide, and the filler is composed of a first infill, a second infill, a third infill, and a fourth infill; wherein the first infill comprises a first compound composition of indium bromide and antimony bromide, the second infill comprises a second compound composition of active metallic element(s), the third infill comprises a third compound composition of one or more rare earth metal halide(s), the fourth infill comprises a fourth compound composition of noble gas, and the second compound composition includes antimony (Sb); wherein the first compound composition includes antimony tribromide (SbBr.sub.3), cobalt bromide (CoBr.sub.2), and/or magnesium bromide (MgBr.sub.2); wherein the light emitted by the bulb is a continuous radiation of full spectrum including ultraviolet ray, visible light, and infrared ray, wherein a spectrum distribution of ultraviolet ray between a wavelength of 350 nm to 400 nm comprises between 6.3% to 7.1% of emission; wherein a spectrum distribution of visible light between a wavelength of 400 nm to 700 nm comprises between 58.8% to 61.3% of emission; and wherein a spectrum distribution of infrared ray between a wavelength of 800 nm to 1100 nm comprises between 24.3% to 25.6% of emission.

2. The electrodeless lamp of claim 1, wherein the third compound composition includes dysprosium (Dy), holmium (Ho), and/or caesium (Cs).

3. The electrodeless lamp of claim 1, wherein the fourth compound composition includes helium (He), neon (Ne), argon (Ar), and/or xenon (Xe).

4. The electrodeless lamp of claim 1, wherein the concentration of the first infill, the second infill, and the third infill is between 0.6-2.9 mg/cm3.

5. The electrodeless lamp of claim 1, wherein the concentration of the first infill, the second infill, and the third infill is between 0.9-2.3 mg/cm3.

6. The electrodeless lamp of claim 1, further comprising a bulb housing composed of a transparent quartz.

7. An electrodeless lamp driven by a microwave generator, comprising: an electromagnetic housing, which has a microwave-providing cavity; a bulb, which is positioned on the microwave-providing cavity of the electromagnetic housing by a lamp body; a conductive mesh, which surrounds the bulb; and a magnetron, which transmits the generated microwave to the microwave-providing cavity by a waveguide; wherein the bulb is filled with a sulfur free filler with mercury-free metal halide, and the filler is composed of a first infill, a second infill, a third infill, and a fourth infill; wherein the first infill comprises a first compound composition of indium bromide and antimony bromide, the second infill is composed of a second compound composition of active metallic element(s), the third infill is composed of a third compound composition of one or more rare earth metal halide(s), the fourth infill is composed of a fourth compound composition of noble gas, and the second compound composition includes antimony (Sb); wherein the first compound composition includes antimony tribromide (SbBr.sub.3), cobalt bromide (CoBr.sub.2), and magnesium bromide (MgBr.sub.2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a graph illustrating the comparison between the continuous spectrum of a microwave sulfur lamp of the related art and the spectrum meeting the AM 1.5 G standard;

(2) FIG. 2 is a schematic view of a microwave generator and an electrodeless lamp base used in the present invention;

(3) FIG. 3 is a continuous spectrum diagram of an electrodeless lamp according to the first embodiment of the present invention;

(4) FIG. 4 is a graph illustrating the comparison between the continuous spectrum of an electrodeless lamp according to the second embodiment of the present invention and the solar spectrum meeting the AM 1.5 G standard; and

(5) FIG. 5 is a continuous spectrum diagram of an electrodeless lamp according to the third embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(6) FIG. 2 is a schematic view of an electrodeless lamp 10 of the present invention. The electrodeless lamp 10 of the present invention comprises a lamp body 1, a bulb 2, an electromagnetic housing 3, a conductive mesh 4, a magnetron 5 and a waveguide 6. The electromagnetic housing 3 has a microwave-providing cavity 7. The bulb 2 is positioned on the microwave-providing cavity 7 of the electromagnetic housing 3 by the lamp body 1. The conductive mesh 4 surrounds the bulb 2. The magnetron 5 may transmit the generated microwave to the microwave-providing cavity 7 by the waveguide 6.

(7) Accordingly, the bulb 2 is sealed after it is filled with a filler with mercury-free metal halide which is composed of a first infill, a second infill, a third infill, and a fourth infill. The magnetron 5 provides a microwave with a frequency of 2.45 GHz and a power of 1 kW. Then, the microwave is transmitted to the microwave-providing cavity 7 via the waveguide 6. Meanwhile, the microwave energy is concentrated by the electromagnetic housing 3 to heat the filler within the bulb 2 and to excite the filler into the plasma status to generate the spectrum radiation. After the light rays are output from the bulb 2 through holes of the conductive mesh 4, the continuous radiation of full spectrum meeting the AM 1.5 G standard can be obtained.

(8) In the present invention, to bear the high temperature (about 600 C.-900 C.) generated during the operation of the electrodeless lamp 10, the bulb housing of the bulb 2 of the electrodeless lamp 10 is made of quartz. Additionally, depending on the required power, the size of the bulb 2 is usually 10 cm.sup.3-30 cm.sup.3, and the filler inside the bulb 2 generally ranges from 10 mbar to 100 mbar.

(9) Next, the filler inside the electrodeless lamp 10 of the present invention will be described in detail. As compared to the conventional electrodeless lamp, the electrodeless lamp 10 of the present invention mainly has three technical features.

(10) First, the first feature of the present invention lies in that the main filling substance of the electrodeless lamp 10 is active metal bromide instead of sulfur. This improved electrodeless lamp can avoid the shortcoming in spectrum performance of the microwave sulfur lamp and achieve a wider and more stable spectrum distribution. The main filling substance of the present invention is metal bromide, i.e., indium bromide, antimony tribromide (SbBr.sub.3), cobalt bromide (CoBr.sub.2) and magnesium bromide (MgBr.sub.2), or a mixture of these metal bromides.

(11) When the outer diameter of the bulb 2 is 3.5 cm, the total weight of the added metal bromides may be in the range of 16 mg to 40 mg, i.e., the added metal bromides may be in a concentration range from 0.93 mg/cm.sup.3 to 2.33 mg/cm.sup.3. Thus, there are still great differences in performance between the metal bromides and the metal iodides commonly used in halide lamps with two opposite electrodes or used in a plurality of metal discharge lamps.

(12) Furthermore, the second feature of the present invention lies in that a small amount of active metallic element antimony (Sb) may also be added into the bulb 2 of the electrodeless lamp 10. The addition of Sb will facilitate the rapid activation of the electrodeless lamp 10 and reduce the time required for reactivation of the lamp after the lamp is turned off and cooled. In the related art, sometimes indium (In) is added to achieve the same effect, but the infill of the present invention is mainly composed of antimony bromide. The added Sb may take part in the high-temperature plasma reaction during the operation of the lamp, and will precipitate on the inner wall of the quartz bulb due to oversaturation when the bulb is cooled, and thus, other undesirable chemical reactions can be avoided.

(13) Moreover, the third feature of the present invention lies in that a small amount of rare earth metal halides or transition metal halides may be further added into the bulb 2 of the electrodeless lamp 10. The rare earth metal halides are composed of a mixture of at least one rare earth metal halide. The rare earth metal includes dysprosium (Dy), holmium (Ho), and/or caesium (Cs). The addition of the rare earth metal halides also facilitates the rapid reactivation of the electrodeless lamp (within 30 seconds) after the electrodeless lamp is turned off to overcome the drawback in the related art that the bulb with heat accumulated therein cannot be reactivated. Meanwhile, the light emission efficiency and the color rendering performance of the lamp is improved.

(14) With the aforesaid features, the electrodeless lamp 10 of the present invention has of long service life and extremely low light decay or the like. Moreover, as compared to the conventional lighting application, the spectrum of the light emitted by the electrodeless lamp 10 of the present invention is stable, continuous and wide. The range of the spectrum may further cover ultraviolet light (between 350 nm and 400 nm), visible light and infrared light (between 700 nm and 1,100 nm), and the spectrum distribution thereof is consistent with that of the natural sunlight, so the electrodeless lamp 10 can be used as the standard light source of the solar simulator meeting the AM 1.5 G standard.

(15) In a preferred embodiment of the present invention, the first infill of the electrodeless lamp 10 is composed of a first compound composition of indium bromide and antimony bromide, the second infill is composed of a second compound composition of active metallic element(s), the third infill is composed of a third compound composition of one or more rare earth metal halide(s), and the fourth infill is composed of a fourth compound composition of noble gas.

(16) The first compound composition includes antimony tribromide (SbBr.sub.3), cobalt bromide (CoBr.sub.2), and/or magnesium bromide (MgBr.sub.2); the second compound composition includes antimony (Sb) and/or indium (In); the third compound composition includes dysprosium (Dy), holmium (Ho), and/or caesium (Cs); and the fourth compound composition includes helium (He), neon (Ne), argon (Ar), and/or xenon (Xe).

(17) Specifically, the concentration of the active compound composition (i.e., the collection of the first compound composition, the second compound composition, and the third compound composition) filling in the bulb 2 is between 0.6-2.9 mg/cm.sup.3, and preferably between 0.9-2.3 mg/cm.sup.3. Furthermore, the filler (especially the mercury-free metal halide in the first infill and the rare earth metal halide in the third infill) added into the electrodeless lamp 10 can control the spectrum range and the energy property of the electrodeless lamp 10 by changing the species and the concentration of the filler.

(18) Hereinafter, technical contents of embodiments of present invention will be described in detail.

(19) In the first embodiment of the present invention, an electrodeless lamp 10 is provided. The electrodeless lamp 10 has a spherical bulb housing made of quartz with an outer diameter of 3.5 cm, the volume inside the bulb is 17.16 cm.sup.3, and the fillers inside the bulb are listed as follows:

(20) 1. Indium bromide (InBr): 7 mg

(21) 2. Antimony tribromide (SbBr.sub.3): 22 mg

(22) 3. Antimony (Sb): 6 mg

(23) 4. Dysprosium triiodide (DyI.sub.3): 0.3 mg

(24) 5. Xenon (Xe): 30 torr at 25 C.

(25) The total weight of InBr, SbBr.sub.3, Sb and DyI.sub.3 filling the bulb 2 of the electrodeless lamp 10 in the first embodiment is 35.3 mg, i.e., the concentration of the first infill, the second infill and the third infill is 2.06 mg/cm.sup.3. After the fourth infill (Xe) is added into the bulb 2 and then the bulb 2 is sealed, the bulb 2 is inserted into the structure as shown in FIG. 2 and is rotated at a rotational speed of 1,200 rpm to 3,000 rpm. Then, under the condition of 2.45 GHz and 1,000 W, the emission spectrum as shown in FIG. 3 can be obtained.

(26) Thereafter, a spectro-color analyzer and a sun spectroradiometer are adopted to measure the emission spectrum of the electrodeless lamp 10 excited by the microwave, and a relative color temperature of 5,233 K can be obtained. Results of the spectrum distribution between 400 nm and 1,100 nm are as shown in Table 1 and FIG. 3, and the results meet requirements of the A-grade light source of the solar simulator in the IEC 60904-9 (and JIS C 8912) specification. As can be known from this, these species of fillers of the electrodeless lamp 10 at the aforesaid proportions provide an ideal continuous radiation of full frequency spectrum and provide good lighting efficacy.

(27) TABLE-US-00001 TABLE 1 Spectrum Distribution Comparison between the IEC 60904-9 Specification and the Electrodeless Lamp of the First Embodiment IEC 60904-9 Specification Electrodeless lamp of Wavelength the first embodiment range Spectrum Spectrum Spectrum Waveband (nm) distribution (%) distribution (%) matching 1 400-500 18.4 18.2 0.991 2 500-600 19.9 21.3 1.07 3 600-700 18.4 19.3 1.05 4 700-800 14.9 14.9 1.00 5 800-900 12.5 11.6 0.928 6 900-1,100 15.9 14.0 0.919 400-1,100 100.0 100.0 Grade A

(28) Next, in the second embodiment of the present invention, another electrodeless lamp 10 is provided. The electrodeless lamp 10 also has a spherical bulb housing made of quartz with an outer diameter of 3.5 cm, the volume inside the bulb is 17.16 cm.sup.3, and the fillers inside the bulb are listed as follows:

(29) 1. Indium bromide (InBr): 10 mg

(30) 2. Antimony tribromide (SbBr.sub.3): 12 mg

(31) 3. Antimony (Sb): 3 mg

(32) 4. Cobalt iodide (CoI.sub.2): 1.0 mg

(33) 5. Dysprosium triiodide (DyI.sub.3): 0.3 mg

(34) 6. Xenon (Xe): 15 torr at 25 C.

(35) The total weight of InBr, SbBr.sub.3, Sb, CoI.sub.2 and DyI.sub.3 filling the bulb 2 of the electrodeless lamp 10 in the second embodiment is 26.3 mg, i.e., the concentration of the first infill, the second infill and the third infill is 1.54 mg/cm.sup.3. Next, after the fourth infill (Xe) is added into the bulb 2 and then the bulb 2 is sealed, the bulb 2 is inserted into the structure as shown in FIG. 2 and is rotated at a rotational speed of 3,000 rpm. Then, under the condition of 2.45 GHz and 1,000 W, the emission spectrum as shown in FIG. 4 can be obtained.

(36) Thereafter, the spectro-color analyzer and the sun spectroradiometer are adopted to measure the emission spectrum of the electrodeless lamp excited by the microwave, and a relative color temperature of 5,900 K can be obtained. Results of spectrum distribution between 350 nm and 750 nm are as shown in Table 2 and FIG. 4. The results meet the requirements of the A-grade light source of the solar simulator required for measurement of amorphous thin film solar cells and modules in the JIS C 8933 specification. As can be known from this, these species of fillers of the electrodeless lamp at the aforesaid proportions provide another ideal continuous radiation of full frequency spectrum and provide good lighting efficacy.

(37) TABLE-US-00002 TABLE 2 Spectrum Distribution Comparison between the JIS C 8933 Specification and the Electrodeless Lamp of the Second Embodiment JIS C 8933 Specification Electrodeless lamp of the Wavelength second embodiment range Spectrum Spectrum Spectrum Waveband (nm) distribution (%) distribution (%) matching 1 350-400 6.2 7.1 1.140 2 400-450 11.8 14.5 1.230 3 450-500 14.9 16.4 1.100 4 500-550 14.6 14.4 0.987 5 550-600 14.3 14.1 0.986 6 600-650 13.8 12.4 0.895 7 650-700 12.9 11.3 0.876 8 700-750 11.5 9.8 0.854 350-750 100.0 100.0 Grade A

(38) In the third embodiment of the present invention, another electrodeless lamp 10 is provided. The electrodeless lamp 10 also has a spherical bulb housing made of quartz with an outer diameter of 3.5 cm, the volume inside the bulb is 17.16 cm.sup.3, and the fillers inside the bulb are listed as follows:

(39) 1. Indium bromide (InBr): 8 mg

(40) 2. Antimony tribromide (SbBr.sub.3): 21 mg

(41) 3. Antimony (Sb): 6 mg

(42) 4. Dysprosium triiodide (DyI.sub.3): 0.6 mg

(43) 5. Xenon+argon (Xe+Ar): 20 torr at 25 C.

(44) The total weight of the InBr, SbBr.sub.3, Sb and DyI.sub.3 filling the bulb 2 of the electrodeless lamp 10 in the third embodiment is 35.6 mg, i.e., the concentration of the first infill, the second infill and the third infill is 2.07 mg/cm.sup.3. After the fourth infill (Xe and Ar) is added into the bulb 2 and then the bulb 2 is sealed, the bulb 2 is inserted into the structure as shown in FIG. 2 and is rotated at a rotational speed of 3,000 rpm. Then, under the condition of 2.45 GHz and 1,000 W, the emission spectrum as shown in FIG. 5 can be obtained.

(45) Thereafter, the spectro-color analyzer and the sun spectroradiometer are adopted to measure the emission spectrum of the electrodeless lamp excited by the microwave, and a relative color temperature of 5,651 K can be obtained. The results of the spectrum distribution between 350 nm and 1,100 nm are as shown in Table 3, Table 4 and FIG. 5. The results meet requirements of the A-grade light source of the solar simulator in the IEC 60904-9 (and JIS C 8912) and JIS C 8933 specifications. As can be known from this, these species of fillers of the electrodeless lamp 10 at the aforesaid proportions provide a broad and continuous radiation of full frequency spectrum and provide good lighting efficacy.

(46) TABLE-US-00003 TABLE 3 Spectrum Distribution Comparison between the IEC 60904-9 Specification and the Electrodeless Lamp of the Third Embodiment IEC 60904-9 Specification Electrodeless lamp of the Wavelength third embodiment range Spectrum Spectrum Spectrum Waveband (nm) distribution (%) distribution (%) matching 1 400-500 18.4 20.6 1.12 2 500-600 19.9 21.9 1.10 3 600-700 18.4 18.8 1.02 4 700-800 14.9 14.3 0.961 5 800-900 12.5 10.9 0.868 6 900-1,100 15.9 13.4 0.846 400-1,100 100.0 100.0 Grade A

(47) TABLE-US-00004 TABLE 4 Spectrum Distribution Comparison between the JIS C 8933 Specification and the Electrodeless Lamp of the Third Embodiment JIS C 8933 Specification Electrodeless lamp of the Wavelength third embodiment range Spectrum Spectrum Spectrum Waveband (nm) distribution (%) distribution (%) matching 1 350-400 6.2 6.3 1.02 2 400-450 11.8 12.6 1.07 3 450-500 14.9 15.5 1.04 4 500-550 14.6 14.7 1.01 5 550-600 14.3 15.1 1.06 6 600-650 13.8 13.3 0.965 7 650-700 12.9 12.3 0.952 8 700-750 11.5 10.2 0.886 350-750 100.0 100.0 Grade A

(48) According to the above descriptions, the electrodeless lamp 10 of the present invention can generate spectrum continuous radiation meeting the AM 1.5 G standard to cover the ultraviolet light spectrum, the visible light spectrum, and the infrared light spectrum, and the electrodeless lamp 10 can be further used in the field of solar simulators with advantages of long service life, extremely low light decay or the like.

(49) The above disclosure is related to the detailed technical contents and inventive features thereof. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof. Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended.