Abstract:
A multi-tube fluorescent discharge lamp, which is constructed of multiple glass tubes of different caliber in coaxial structure, the both sides of the inner most tube are connected to a cathode respectively, by isolating, perforating and blocking the discharge path, forming a successive discharge path, and coating phosphor on surface of the discharge tubes. The Invention can then have more fluorescent area than a conventional fluorescent lamp of the similar size and higher lumen as well as power transfer factor. Compared with the power consumption of a conventional fluorescent discharge lamp, the Invention therefore has higher luminous flux.

Description:
Background of Invention  
         [0001]    1. Field of the Invention  
           [0002]    The Invention relates to fluorescent discharge lamps, and more particularly, to a multi-tube fluorescent discharge lamp which is constructed of multiple glass tubes of different caliber in coaxial structure, the both sides of the inner most tube are connected to a cathode respectively, by isolating, perforating and blocking the discharge path, forming successive discharge chambers, and coating fluorescent material on surface of the discharge tubes. The Invention can then have more fluorescent area than a conventional fluorescent lamp of the similar size and higher lumen as well as power transfer factor. Compared with the power consumption of a conventional fluorescent discharge lamp, the Invention therefore has higher luminous flux.  
           [0003]    2. Description of the Prior Art  
           [0004]    Generally, a conventional fluorescent discharge lamp uses one straight or round tube. To minimize the size and to increase the illumination, there is a kind of compact fluorescent discharge lamp that the straight tube is bent into a wreath or U type. Alternatively, couples of short straight fluorescent tubes are aligned and connected in parallel, on the both terminations of the tube with a cathode tungsten filament that coated with oxide such as Ba, Sr and Ca. In the discharge tube is in a state of vacuum and with little Hg and Ar, which helps the discharge.  
           [0005]    The conventional fluorescent lamp tubes is usually a round cross-section and only one layer of fluorescent material such as phosphor is coated on the surface of the tube inside. When the cathodes on both sides of the tube is started up by current and high-voltage power is applied to the cathodes on both sides of tube, the electron is released between the two cathodes and make the tube glow discharge. The Ar and Hg vapor molecules are also stimulated to create plasma; the ion and ultraviolet rays also impact the phosphor, so that the potential energy is transferred into light from the phosphor.  
           [0006]    Because the cross-section area of a round tube is larger than that of any shape, the average density of electronic flux of the round tube inside is lower than other shape of tube. Furthermore, the electronic flux on the discharge path is concentrated nearby the axis of the discharge tube; the density of the electronic flux nearby the surface of the discharge tube inside gets lower.  
           [0007]    Therefore, the luminous flux in a round tube can not in proportion to raise by increasing the diameter of the tube to expand the area of phosphor, much of energy nearby the axis in the discharge tube will be depleted and transfer into heat, the transferring factor of the lumen (Lm) and Watt (W) remains not high enough.  
           [0008]    Although there is another kind of lamp which build-in a lot of segmented tubes and coated with phosphor to increase the illuminant fluorescent area, but the lamp does not forming a successive discharge path, therefore, it does not guarantee stable discharge path or equable plasma status, nor adequate and complete illumination of fluorescent layer in the discharge tube, because the discharge path proceeds in the shortest distance.  
           [0009]    Moreover, due to the narrow spectrum of conventional fluorescent discharge lamp, the color-rendering index (Ra) is low and the color temperature (K) is high which therefore causes the illuminated object unable to reveal its colors. Besides, for the cathode on both sides of the conventional fluorescent discharge lamp is hit by electron, the tungsten filament is then vaporized to be black and pollutes the fluorescent layer of the tube, hence reduces the illumination efficiency of the fluorescent layer as well as the life cycle of the fluorescent discharge lamp.  
         SUMMARY OF INVENTION  
         [0010]    This Invention is a multi-tube fluorescent discharge lamp; the design concept of the Invention is constructed of multiple discharge glass tubes of different caliber in coaxial structure. By isolating, perforating and blocking the discharge path, and applying phosphor on surface of the discharge tubes, a thin and transparent film of fluorescent coating is then created, allowing the light of the inner tubes pass through each of the coatings to the outside of the lamp. In addition, a pair of cathodes as hot or cold cathode helps the electronic flux in the vacuum to be accelerated and hit the Hg molecule, which is then stimulated to create plasma. The coating of fluorescent on the inner layer surface of the discharge tube is impacted by electron ion and UV rays and then to emits light. Under the same power rate and with the same volume of lamp, the tubes of the multi-tube fluorescent discharge lamp aligned in coaxial structure have smaller cross-section area than that of conventional fluorescent discharge lamp so that this Invention can allow higher density of electron flux to pass through the discharge path in the tubes. Therefore, the high-density electron ion has better stimulating effects on the fluorescent coating and the illuminant fluorescent area is larger than conventional fluorescent discharge lamp, both advantages increasing the luminous flux.  
           [0011]    Compared to conventional fluorescent discharge lamp of the same power rate, this Invention is characterized by higher luminance, lower consumption of electric power and lower heat rate. Moreover, because the electric flux of the Invention is less than that of conventional fluorescent discharge lamp, the vaporization caused by electric flux hitting the cathode gets slower and the life cycle of the cathode is longer accordingly than that of conventional fluorescent discharge lamp. It is also feasible to apply ringed cathode to increase the surface area of the hitting of electron flux and then disperse the hitting, so that the oxide material on the surface of the cathode can be protected from rapid consumption. By this way, the multi-tube fluorescent discharge lamp can outlive conventional fluorescent discharge lamp.  
           [0012]    The multi-tube fluorescent discharge lamp whose surface is coated with various fluorescent material of different colors temperature. The fluorescent material, being stimulated, can release fluorescence of different spectrum and create special colors after mixing. Alternatively it can include wider spectrum to improve the color temperature (K) as well as color-rendering index (Ra) to be close to the sun spectrum.  
           [0013]    The multi-tube fluorescent discharge lamp is designed in coaxial structure, aiming to achieve special colorful luminance or balanced spectrum range of light by way of filtering the luminance released from the transparent discharge glass tube of different colors.  
           [0014]    The characteristics of this Invention can be specifically presented by the following detailed figures. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0015]    [0015]FIG. 1 is a partly broken side view of a conventional fluorescent discharge lamp.  
         [0016]    [0016]FIG. 2 to FIG. 9 are cross-sectional views and end views showing a step-by-step process of fabrication of a three-tube fluorescent discharge lamp of a first embodiment.  
         [0017]    [0017]FIG. 10 is a cross-sectional view and end view of the five-tube combination with phosphor of a second embodiment.  
         [0018]    [0018]FIG. 11 is a cross-sectional view and end view of an electrode portion with a straight cathode.  
         [0019]    [0019]FIG. 12 is a cross-sectional view and end view of an electrode portion with a ring cathode.  
         [0020]    [0020]FIG. 13 is a cross-sectional view and end view of a cap.  
         [0021]    [0021]FIG. 14 is a cross-sectional view and end view of a cap combined an electrode portion with a straight cathode.  
         [0022]    [0022]FIG. 15 is a cross-sectional view and end view of a cap combined an electrode portion with a ring cathode.  
         [0023]    [0023]FIG. 16 and FIG. 17 are cross-sectional view to follow the FIG. 9 showing a step-by-step process of fabrication of the three-tube fluorescent discharge lamp of the first embodiment.  
         [0024]    [0024]FIG. 18 is a cross-sectional view of a three-tube fluorescent discharge lamp of a third embodiment.  
         [0025]    [0025]FIG. 19 is a cross-sectional view of a dual-tube fluorescent discharge lamp of a fourth embodiment.  
         [0026]    [0026]FIG. 20 is a cross-sectional view showing a five-tube portion and a pair of electrode portions of the five-tube fluorescent discharge lamp of the second embodiment.  
         [0027]    [0027]FIG. 21 is a cross-sectional view of the three-tube fluorescent discharge lamp of the first embodiment showing a pair of bases unattached.  
         [0028]    [0028]FIG. 22 is a cross-sectional view of the full schematic three-tube fluorescent discharge lamp of the first embodiment.  
         [0029]    [0029]FIG. 23 is a cross-sectional view of the full schematic five-tube fluorescent discharge lamp of the second embodiment.  
         [0030]    [0030]FIG. 24 is a partly broken and cross-sectional view of the full schematic three-tube fluorescent discharge lamp of the first embodiment.  
         [0031]    [0031]FIG. 25 is a partly broken and cross-sectional view of the full schematic five-tube fluorescent discharge lamp of the second embodiment. 
     
    
     DETAILED DESCRIPTION  
       [0032]    According to FIG. 1, illustrates a conventional fluorescent discharge lamp.  
         [0033]    The discharge tube  8  is a straight glass tube, on both sides of the tube are the cathodes  26  whose electrode  28  are connected to the terminal  42  of the tube base  40 . The figure explains clearly that there is only one phosphor layer  18  on the surface of the tube inside. In addition, because the density of electronic flux nearby the axis of the discharge tube is higher than that the electronic flux nearby the phosphor layer  18  of the discharge tube inside. Therefore, much of energy nearby the axis in the discharge tube will be depleted and transfer into heat, the power transfer factor of the lumen needs to be improved.  
         [0034]    According to FIG. 2, the first tube  10  is a round straight glass tube, which is the inner most tube in the multi-tube fluorescent discharge lamp and are where the cathodes  26  located.  
         [0035]    According to FIG. 3, to use as a flame of gas and oxygen or arc heating around the circumference in the vicinity of the middle of the first tube  10  for softening and is rotated in the reverse direction around both ends of the tube, and is twisted at the softening place thus fusing into an isolator  12  to seal the pipeline nearby the middle of the tube to insulate and separating the discharge path of the first tube into two discharge chambers.  
         [0036]    According to FIG. 4, blowing the air in from both ends of the first tube  10 , also heating is performed nearby both ends of isolator  12  on the two circumferences at the position of plural number thus the through-hole  14  of plural number are formed.  
         [0037]    According to FIG. 5, the second tube  16  is a round straight glass tube of which the diameter is slightly larger than that of the first tube  10 , at one end of the second tube  16  is air tight and the air is blown in from another end, or air is blown in from both ends, also heating is performed nearby both ends on the two circumferences at the position of plural number thus the through-hole  14  of plural number are formed.  
         [0038]    According to FIG. 6, the first tube  10 , after passing through the holes, is slid into the second tube  16  in coaxial structure then heating on the circumference of the second tube  16  correspond to the position of isolator  12  of the first tube  10 , also, rotation is made with reverse direction at both ends of the second tube  16 , and is twisted at the softening place of the tube thus fusing into another isolator  12  with the first tube  10  to seal the pipeline of the second tube  16  and separating the discharge path of the second tube  16  into two discharge chambers.  
         [0039]    According to FIG. 7, phosphor layer  18  is coated on the inner and outer layer surface of the first tube  10  and the second tube  16 .  
         [0040]    According to FIG. 8, the third tube  20  is a round straight glass tube of which the diameter is slightly larger than that of the second tube  16 , the phosphor layer  18  is coated on the inner layer surface of the third tube  20 .  
         [0041]    According to FIG. 9, this combination of the first tube  10  and the second tube  16  can be slid into the third tube  20  in coaxial structure.  
         [0042]    According to FIG. 10 and refer to the FIG. 6, just as the combination of the first tube  10  and the second tube  16  to be slid into the third tube  20  in coaxial structure that the diameter of the third tube  20  which is slightly larger than that of the second tube  16 , heating is performed on the circumference of the third tube  20  correspond to the isolator  12  of the second tube  16 , also, rotation is made with reverse direction at both ends of the third tube  20  and is twisted at the softening place of the third tube  20  for fusing with the isolator  12  of the second tube  16 , then to connect and form an isolator  12  of the third tube  20  to seal the pipeline of the third tube  20  and separate the discharge path of the third tube  20 , to allow the air being blown in at both ends of the third tube  20 , also, heating shall be performed on the circumference at both ends of  20  to approach the isolator  12  of the second tube  16  at the position of plural number thus the through-hole  14  with plural number are formed.  
         [0043]    Also, with a glass tube of the fourth tube  22 , which the diameter is slightly larger than that of the third tube  20 , to slide into the combination of the first tube  10 , the second tube  16 , and the third tube  20  into the fourth tube  22  in coaxial structure, heating on the circumference of the fourth tube  22  approach to the isolator  12  of the third tube  20 , at both ends of said the fourth tube  22  is rotated in reverse direction, and twisted at the softening place of the fourth tube  22  for fusing with the isolator  12  of the third tube  20  for connecting and forming an isolator  12  of the fourth tube  22  to seal the pipeline of the fourth tube  22 , separating the discharge path of the fourth tube  22 , thus forming two discharge chambers so that air can be blown in from both ends of the fourth tube  22 , also, heating is performed on the circumference to approach both ends of the fourth tube  22  and at the position of plural number, thus extruding through-holes  14  with plural number.  
         [0044]    The phosphor layer  18  is formed at the inner and outer layer surface of the combination of the first tube  10 , the second tube  16 , the third tube  20  and the fourth tube  22 , also formed at the inner layer surface of the fifth tube  24 . This connected combination of the first tube  10 , the second tube  16 , the third tube  20  and the fourth tube  22  shall be slid into the fifth tube  24  in coaxial structure.  
         [0045]    According to FIG. 11, one stem  34  is a conical glass post, one of its ends with smaller diameter can seal and fix the plural electrode  28  which is connected with a straight form cathode  26 , one pipe  32  is connected with the sealed end of the fixed plural electrode  28 , its opening hole  30  is located the sealed end and communicated with pipe  32 .  
         [0046]    According to FIG. 12, and refer to the FIG. 11, the electrodes  28  which is connected with a ring cathode  38 .  
         [0047]    According to FIG. 13, a cap  36  its inner diameter is same as the outer diameter of the first tube  10 , the outer diameter of cap  36  is the same as the diameter of the outer most discharge tube.  
         [0048]    According to FIG. 14, the structure of stem is same as FIG. 11 above, however, for the conical glass post, the larger end is connected with a cap  36 , the outer diameter of said the cap  36  is the same as the diameter of the outer most tube of the multi-tube fluorescent discharge lamp.  
         [0049]    According to FIG. 15 and refer to the FIG. 14, the structure same as FIG. 14, however, its electrodes  28  is connected with a ring cathode  38 .  
         [0050]    According to FIG. 16 and refer to the FIG. 9, also including plural number stem  34 , said stem  34  includes a cathode  26 , plural electrode  28 , and connects with a cap  36 , said cathode  26  is assembled in the two discharge chamber of the first tube  10  respectively, the outer diameter of the cap  36  is the same as that of the third tube  20 .  
         [0051]    According to FIG. 17 and refer to the FIG. 16, the cathode  26  of plural number stem  34  are slid into the two discharge chambers of the first tube  10  respectively, heating at the outskirts of the circumference at both ends of all the tubes, melting and sealing both ends of the tubes.  
         [0052]    Or use the cathode  26  of plural number stem  34  with cap  36  is slid into the two discharge chambers of the first tube  10  respectively, heating on the circumferences of cap  36  correspond to the both ends of all the tubes, and at both ends of all the tubes can be melted and sealed. Due to the sealing of both ends of all discharge tubes and isolator  12  and through-hole  14  of the first tube  10  and the second tube  16 , thus, forming successive discharge chambers.  
         [0053]    According to FIG. 18, the first tube  10  is a round straight glass tube, in which a pair of electrodes  28  and one pipe  32  with said tube are slid in coaxial structure, and heating at one end of the tube for softening, by means of clamping, pressing and sealing the tube, the pair of electrodes  28  and pipe  32  can be fixed, air is blown into the pipe  32 , by means of the heating at the end of sealed, a hole  30  can be extruded, forming a phosphor layer  18  on the surface of said tube outside, install cathode  26  in the pair of electrode  28 , and the other first tube  10  can be completed with the method mentioned above.  
         [0054]    The second tube  16  is a round straight glass tube, its diameter is slightly larger than that of the first tube  10 , the air is blown in at both ends of the second tube  16 , or one end of said tube is air tight and the air is blown in from another end, also, heating is performed on the circumferences to approach both ends of the second tube  16 , at the position of plural number thus extruding the through-hole  14  with plural number, and heating is also performed at the circumference to approach the middle of the second tube  16 , rotated with reverse direction at both ends of the second tube, and is twisted at the softening place of the tube thus fusing into an isolator  12  to seal the path of the discharge tube and separate the discharge path of the second tube  16 .  
         [0055]    The third tube  20  is a round straight glass tube, its diameter is slightly larger than that of the second tube  16 , the phosphor layer  18  is formed in the inner layer surface of the third tube  20  and in the inner and outer layer surface of the second tube  16 .  
         [0056]    The two cathodes  26  of the first tubes  10  can be slid into the two-discharge chamber of the second tube  16  in coaxial structure respectively, that the cathodes  26  installed oppositely to approach the isolator  12 , heating at the outskirts of the circumference at both ends of the first tube  10  and the second tube  16 , sealing both ends of the tubes, then slid into the third tube  20  in coaxial structure, heating at the outskirts of the circumference at both ends of the second tube  16  and the third tube  20 , sealing both ends of all discharge tubes. Due to the sealing of both ends of all discharge tubes and isolator  12  and through-hole  14  of the second tube  16 , thus, forming successive discharge chambers.  
         [0057]    As mentioned above, heating at the outskirts of the circumference at both ends of the first tube  10 , the second tube  16 , the third tube  20  can make it soft and melt and seal both ends of all discharge tubes, also, a cap  36  can be placed at both ends of the multi-tube, after the cap  36  on the circumferences correspond to the both ends of all discharge tubes is heated, both ends of the first tube  10 , the second tube  16 , the third tube  20  can be melted and sealed, thus, forming successive discharge chambers.  
         [0058]    For the multi-tube fluorescent discharge lamp with more than S tubes, which can be formed by means of the method mentioned above with the total tube number N (N=odd number), tube number of different tube with different diameter, the isolator  12  can be formed from the second tube  16  to the (N−1)th tube to approach the middle of the tubes. The through-hole  14  with plural number can be formed at the even number tube and from the second tube  16  to the (N−1)th tube to approach the both ends of the tubes at the position of circumference, the through-hole  14  with plural number can be formed at the odd number tube from third tube  20  to (N−2)th tube to approach the both ends of the isolator  12  at the position of circumference.  
         [0059]    The phosphor layer  18  coated on the inner and outer layer surface of the tube from the second tube  16  to the (N-1)th tube, and coated on the outer layer surface of the tube on the first tube  10 , and coated on the inner layer surface of the Nth tube, a pair of electrode  28  of the cathode  26  connecting to terminal  42  of base  40  respectively.  
         [0060]    According to FIG. 19, the first tube  10  is a round straight glass tube, heating is performed at the circumference to approach the middle of the first tube  10 , and rotation is made with reverse direction at both ends of the first tube  10 , and is twisted at the softening place of the tube thus fusing into an isolator  12  to seal the pipeline of the first tube  10 , thus, forming two discharge chambers, and air is blown in from both ends of said tube and heating is performed at the circumferences approach to the both ends, at the position of plural number to extrude the through-hole  14  with plural number, forming the phosphor layer  18  on the inner and outer layer surface of said tube.  
         [0061]    A second tube  16  is a round straight glass tube of which the diameter is slightly larger than that of the first tube  10 , the phosphor layer  18  is coated on the inner layer surface of the second tube  16 , then the first tube  10  be slid into the second tube  16  in coaxial structure, also, plural number stem  34 , said stem  34  includes a cathode  26 , a pair of electrode  28 , a hole  30 , a pipe  32 , its plural number cathode  26  is placed in the two discharge chambers of the first tube  10 .  
         [0062]    Heating is performed at the outskirts of circumference at both ends of the first tube  10  and the second tube  16  to melt and seal both ends of the first tube  10  and the second tube  16  with the stem  34 , due to the isolator  12  and the through-hole  14  of the first tube  10 , and the sealing of both ends of all discharge tubes, thus, forming successive discharge chambers.  
         [0063]    For the multi-tube fluorescent discharge lamp with  4  tubes or more than  4  tubes, which can be formed by means of the method mentioned above with the total tube number N (N=even number), tube number of different tube with different diameter, the isolator  12  can be formed from the first tube  10  to the (N−1)th tube to approach the middle of the tubes. The through-hole  14  with plural number can be formed at the odd number tube and from the first tube  10  to the (N−1)th tube to approach the both ends of the tubes at the position of circumference, the through-hole  14  with plural number can be formed at the even number tube from the second tube  16  to (N−2)th tube to approach the both ends of the isolator  12  at the position of circumference, also, with one cap  36  or the stem  34  connecting a cap  36  at both ends of the multi-tube to heat the cap  36  at the circumferences of both ends of the corresponding discharge tubes, both ends of all tubes can be melted and sealed, the phosphor layer  18  coated on the inner and outer layer surface of the tube from the second tube  16  to the (N−1)th tube, and coated on the outer layer surface of the first tube  10 , and coated on the inner layer surface of the Nth tube, a pair of electrode  28  of the cathode  26  connecting to terminal  42  of base  40  respectively.  
         [0064]    According to FIG. 20 and refer to the FIG. 10, also including plural number stem  34 , said stem  34  includes a cathode 26 , a pair of electrode  28 , and connects with one cap  36 , said cathode  26  is assembled in the two discharge chambers of  10 , the outer diameter of the cap  36  is the same as that of the third tube  20 . The cathode  26  of plural number stem  34  is assembled in the two discharge chambers of the first tube  10  respectively, heating is performed at the outskirts of the circumference correspond to the both end of all tubes, its softening can melt and seal both ends of all tubes or plural number stem  34  connecting with cap  36  placed at both ends of the first tube  10 , the second tube  16 , the third tube  20 , the fourth tube  22  and the fifth tube  24 , heating on the corresponding position at the circumference of all discharge tubes of the two cape  36  can seal both ends of all tubes. Due to the isolator  12 , the through-hole  14  and sealing of both ends of all discharge tubes, thus, forming successive discharge chambers.  
         [0065]    For the multi-tube fluorescent discharge lamp with more than  5  tubes, which can be formed by means of the method mentioned above with the total tube number N (N=odd number), tube number of different tube with different diameter, the isolator  12  can be formed from the first tube  10  to the (N−1)th tube to approach the middle of the tubes. The through-hole  14  with plural number can be formed at the even number tube and from the second tube  16  to the (N−1)th tube to approach the both ends of the tubes at the position of circumference, the through-hole  14  with plural number can be formed at the odd number tube from the first tube  10  to the (N−2)th tube to approach the both ends of the isolator  12  at the position of circumference, the phosphor layer  18  coated on the inner and outer layer surface of the tube form the first tube  10  to the (N−1)th tube, and the inner layer surface of the Nth tube, a pair of electrode  28  of the cathode  26  connecting to terminal  42  of base  40  respectively.  
         [0066]    According to FIG. 21 and refer to the FIG. 17, one base  40  with a pair of terminal  42  at both ends of the three-tube fluorescent discharge lamp, the electrode  28  of the cathode welded on said terminal  42  respectively.  
         [0067]    According to FIG. 22, when negative HV presents at one of those electrode  26  in the first discharge tube  10 , electrons released by its electrode are attracted by positive HV at another electrode  26  in another first discharge tube  10 , for moving into second discharge tube  16  from through-hole  14  of the first discharge tube  10 , via the third discharge tube  20  from through-hole  14  of the second discharge tube  16 ; electrons passing through the third discharge tube  20  enter into another end of second discharge tube  16  from through-hole  14  thereof, and into another end of the first discharge tube  10  from through-hole  14  thereof, then the electrons hit another electrode  26 ; the electrode  26  with positive charges are converted into negative charges during the next half cycle of the alternating current, with negative charges in said another end of discharge tube  10 , to release the electrons traveling in reverse along the route of electron movement of the first half cycle to repeat the process upon arriving at the corresponding electrode  26  with positive charges during which electronic irons and ultraviolet excited by the discharge chamber of each discharge tube, the phosphor on the surface of each discharge tube will be impacted and to emit light.  
         [0068]    According to FIG. 23, when negative HV presents at one of those electrode  26  in the first discharge tube  10 , electrons released by its electrode are attracted by positive HV at another electrode  26  in another first discharge tube  10 , for moving into second discharge tube  16  from through-hole  14  of the first discharge tube  10 , via the third discharge tube  20  from through-hole  14  of the second discharge tube  16 , then fourth discharge tube  22  from through-hole  14  of the third discharge tube  20  and finally into the fifth discharge tube  24  from through-hole  14  of fourth discharge tube  22 ; electrons passing through the fifth discharge tube  24  enter into another end of fourth discharge tube  22  from through-hole  14  thereof, then into another end of third discharge tube  20  from through-hole  14  thereof and into another end of second discharge tube  16  from through-hole  14  thereof reaching another end of the first discharge tube  10  from through-hole  14  thereof, then the electrons hit another electrode  26 ; the electrode  26  with positive charges are converted into negative charges during the next half cycle of the alternating current, with negative charges in said another end of discharge tube  10 , to release the electrons traveling in reverse along the route of electron movement of the first half cycle to repeat the process upon arriving at the corresponding electrode  26  with positive charges during which electronic irons and ultraviolet excited by the discharge chamber of each discharge tube, the phosphor on the surface of each discharge tube will be impacted and to emit light.  
         [0069]    According to FIG. 24, at the related positions between all discharge tubes, the isolator  12  formed at the first tube and second tube to approach the middle of these tubes, the cathode  26  is located in the discharge chambers of the first tube  10  respectively. Forming through-hole  14  with plural number at the circumference to approach the both ends of the isolator  12  of the first tube  10 , forming through-hole  14  with plural number at the circumference to approach the both ends of the second tube  16 . The phosphor layer  18  coated on the inner and outer layer surface of the first tube  10 , the second tube  16  and the inner layer surface of the third tube  20 , a pair of electrode  28  of the cathode  26  connecting to terminal  42  of base  40  respectively.  
         [0070]    According to FIG. 25, at the related positions between all discharge tubes, the isolator  12  formed at the first tube  10 , the second tube  16 , the third tube  20  and fourth tube  22  to approach the middle of these tubes, the cathode  26  is located in the discharge chambers of the first tube  10  respectively. Forming through-hole  14  with plural number at the circumference to approach the both ends of the isolator  12  of the first tube  10  and the third tube  20 , forming through-hole  14  with plural number at the circumference to approach the both ends of forming through-hole  14  with plural number the second tube  16  and fourth tube  22 . The phosphor layer  18  coated on the inner and outer layer surface of the first tube  10 , the second tube  16 , the third tube  20 , the fourth tube  22 , and the inner layer surface of the fifth tube  24 , a pair of electrode  28  of the cathode  26  connecting to terminal  42  of base  40  respectively.  
         [0071]    Subsequently, Heating on outside of the combination of tubes; meanwhile, blowing in dry air from one of the pipe  32  and exhausted from the other pipe  23 , to accelerate drying the phosphor layers. After the drying process completed, one of the pipe  23  is heated and sealed, then several mg of mercury (Hg) is injected into the discharge chamber from the opening pipe  32 , then the discharge chamber is vacuumed and then filled with little of Ar gas such as several hundreds Pa in pressure, and then sealing the pipe  23 . Afterward the combination of tubes is put in an environment of electromagnetic field such as microwave chamber to agitate the liquid Hg into vapor Hg, applying current and high voltage on the both cathodes, a glow discharge will be generated in the discharge lamp.  
         [0072]    It will be now apparent to those skilled in the art that other embodiments, details and uses can be made consistent with the letter and spirit of the foregoing disclosure and within the scope of this patent, which is limited only by the following claims, construed in accordance with the patent law, including the doctrine of equivalents.