Abstract:
The present invention discloses a light emitting diode apparatus and a manufacturing method thereof, and more particularly to provide an AC-driven white light emitting diode apparatus comprising a plurality of groups of the AC-driven light emitting diode chips with different emission wavelengths and a plurality of groups of the DC-driven light emitting diode chips with different emission wavelengths. The AC-driven white light emitting diode apparatus manufactured by the disclosed method has the properties of high color rendering, high light emitting efficiency, and stable chromaticity coordinate.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention is related to a light emitting diode (LED) apparatus and a manufacturing method thereof, and more particularly to an alternating current driven (AC-driven) white LED apparatus manufacturing method, and an AC-driven white LED apparatus capable of achieving a high color rendering, a high light emitting efficiency and a stable chromaticity coordinate. 
         [0003]    2. Description of the Related Arts 
         [0004]    With reference to  FIG. 1  for a schematic view of a LED array as disclosed in U.S. Pat. No. 6,957,899, the LED array  1  comprises an AC power supply  12 , a first LED array  14  and a second LED array  18 . In  FIG. 1 , the first LED array  14  and the second LED array  18  are composed of a plurality of micro-LED chips connected in series with each other and arranged on a same plane  10 . An AC voltage with a positive half wave period is applied to drive the first LED array  14  to emit light, and an AC voltage with a negative half wave period is applied to drive the second LED array  18  to emit light, respectively. In general, the utility power of each different country has an AC frequency with 50-60 Hz which is greater than the frequency required for the duration of vision of human beings, so that we cannot visually distinguish the alternating light emissions of the first and second LED arrays  14 ,  18  in the LED array  1 , thereby achieving the objective of AC-driven applications. 
         [0005]    At present, the yield rate of the GaN-based LED chips is unable to provide a uniform brightness or a 100% light emitting efficiency of each micro-LED chip. therefore if an AC voltage is applied to drive the first LED array  14  to emit light, as we know, light and heat will be generated. Therefore, the temperature and voltage will be deviated easily to cause a non-uniform light emission. Furthermore, if an additional AC voltage of the power supply  12  produces a pluse onto the light emitting device, the LED chip in the light emitting device may be broken easily, hence, the reliability will become a big issue as well as a major drawback of the disclosed LED array in this invention. 
         [0006]    To overcome the aforementioned drawback of the GaN LED array disclosed in U.S. Pat. No. 6,957,899, a light emitting device as shown in  FIG. 2  is disclosed in TW Pat. Publication No. 200826320, wherein the light emitting device comprises at least one correction circuit  20  to serve as a temperature and voltage compensation circuit provided for the operation of an AC-driven LED component  21  and achieve the effect of absorbing pluses. However, the aforementioned invention still has a drawback of failing to compensate the color rendering during light emitting. 
         [0007]    With reference to  FIG. 3  for a schematic view of a LED device disclosed in U.S. Application Publication No. 20090109151, wherein the white light emitting apparatus  30  is composed of two groups of the AC-driven LED  31  and  32 , with different emission wavelengths from each other, and a phosphor material  33  to improve the color rendering. One of the methods is to provide an AC-driven blue-emitting LED and an AC-driven green-emitting LED, and a red-emitting phosphor is encapsulated on the AC-driven blue-emitting LED. Another method is to provide an AC-driven blue-emitting LED and an AC-driven red-emitting LED, and a phosphor is encapsulated on the AC-driven blue-emitting LED. The phosphor can absorb a part of the radiation emission from the blue-emitting LED and itself emit in spectral regions ranging from blue to red. Although, the prior art discloses the methods to improve the color rendering of white LED, yet the transfer efficiency of red-emitting phosphor, in the spectral region ranging from 600 to 630 nm, is not satisfactory even though the manufacturing technology is very mature. Hence, the first method can improve the color rendering, but it is hard to effectively enhance the light emitting efficiency of the light emitting apparatus. Moreover, the second method has the potential to improve the color rendering and avoid the decrease of light emitting efficiency. It is noteworthy that, if the group of the AC-driven red-emitting LED is made by the AlInGaP-based compound semiconductors, it will cause a worse stability in an operation ambiance of higher temperature due to the energy band gap of the AlInGaP is easy to shrink when the ambient temperature increases. In other words, it is hard to control the chromaticity coordinate of the white LED due to the large drift of the emission wavelength. Hence, the method still has the drawback in practical application. 
         [0008]    With reference to  FIG. 4  for a schematic view of a LED device disclosed in U.S. Publication No. 20080218098, a bridge rectifying circuit  40  composed of another set of LEDs is added to improve the reliability of operating an AC-driven LED device and protect a LED array  41 . However, the bridge rectifying circuit  40  is directly formed on a substrate used by the LED array  41  and disposed at an external edge. In other words, the LED array  41  and the bridge rectifying circuit  40  are produced in a same fabrication process, and the bridge rectifying circuit  40  not only provides an AC-to-DC conversion function, but also has the function of emitting light. However, this method is unable to produce a high emitting efficiency LED assembly with different light emission wavelengths on the same substrate by the epitaxial and chip fabrication process, thus, the method still has the drawback of failing to provide the effect of compensating the color rendering. 
         [0009]    In view of the aforementioned shortcomings of the prior arts, the inventors of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a light emitting device according to the present invention to overcome the shortcomings of the prior arts. 
       SUMMARY OF THE INVENTION 
       [0010]    Therefore, the primary purpose of the present invention is to provide a LED apparatus having the properties of high color rendering, high light emitting efficiency and stable chromaticity coordinate. 
         [0011]    In accordance with the objective of the present invention, a LED apparatus is provided. The LED apparatus comprises a lead frame, at least one group of AC-driven micro-LED chips, at least one group of DC-driven LED chips, and at least one wavelength conversion phosphor material for absorbing radiation emission of the chips. The group of the AC-driven micro-LED chips and the group of the DC-driven LED chips are individually mounted onto the lead frame and connected by a conductive wire to form the LED apparatus capable of being driven by AC power source, the wavelength conversion phosphor material absorbs a part of the radiation emission of the chips thereby converting a spectral region thereof to have a different peak wavelength. 
         [0012]    In addition, a LED apparatus is further provided, The LED apparatus comprises a lead frame, at least one group of AlInGaN-based LED chips, at least one group of InGaPN-based LED chips, and at least one wavelength conversion phosphor material disposing on the at least one group of AlInGaN-based LED chips for absorbing radiation emission therefrom. The group of the AlInGaN-based LED chips and the group of the InGaPN-based LED chips are individually mounted onto the lead frame and connected by a conductive wire to form the LED apparatus capable of being driven by AC power source, the wavelength conversion phosphor material absorbs a part of the radiation emission from the groups of the AlInGaN-based LED chips thereby converting a spectral region thereof to have a different peak wavelength. 
         [0013]    Further, a method for manufacturing the LED apparatus is also provided. The method for manufacturing the LED apparatus includes the steps of: providing a lead frame; mounting at least one group of AC-driven micro-LED chips and at least one group of DC-driven LED chips on the lead frame; electrically connecting the groups of the AC-driven micro-LED chips and the DC-driven LED chips; and providing a mixed resin comprising at least one phosphor formed over the groups of LED chips. 
         [0014]    In view of above, the LED apparatus and manufacturing method thereof according to the present invention have the advantages are as follows:
       (1) The LED apparatus is composed of one group of AC-driven micro-LED chips, one group of cascading DC-driven LED chips, and one phosphor material. The aforementioned apparatus is expected to achieve the applications of an AC-driven white LED apparatus having the properties of a high color rendering, a high light emitting efficiency and a stable chromaticity coordinate.   (2) The LED apparatus is composed of one group of AlInGaN-based LED chips, at least one group of InGaPN-based LED chips, and at least one phosphor material. The aforementioned apparatus is expected to achieve the applications of an AC-driven white LED apparatus having the properties of a stable chromaticity coordinate.       
 
         [0017]    To make it easier for our examiner to fully understand the technical characteristics and the effects of the present invention, we use preferred embodiments and related drawings for the detailed description of the present invention as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a schematic view showing a conventional LED array structure. 
           [0019]      FIG. 2  is a schematic view showing a conventional light emitting apparatus structure. 
           [0020]      FIG. 3  is a schematic view showing another conventional light emitting apparatus structure. 
           [0021]      FIG. 4  is a schematic view showing another conventional light emitting device structure. 
           [0022]      FIG. 5  is a schematic view showing the light emitting apparatus structure in accordance with the present invention. 
           [0023]      FIG. 6  is a schematic view showing another light emitting apparatus structure in accordance with the present invention. 
           [0024]      FIG. 7  is a schematic view showing another light emitting apparatus structure in accordance with the present invention. 
           [0025]      FIG. 8  is a schematic view showing a further light emitting apparatus structure in accordance with the present invention. 
           [0026]      FIG. 9A-9C  is a schematic view of an equivalent circuit in accordance with a preferred embodiment of the present invention. 
           [0027]      FIG. 10  is a manufacturing flow chart showing a preferred embodiment of the LED apparatus manufacturing method in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]    With reference to  FIG. 5  for a schematic view of a LED apparatus structure in accordance with the present invention, The LED apparatus comprises a lead frame  51 , a first group of the LED chips  52 , a second group of the LED chips  53 , and a third group of the LED chips  54 , at least one wavelength conversion phosphor material  55 , and one encapsulated resin  56 . The wavelength conversion phosphor material  55  is mixed with the encapsulated resin  56 , and the mixed resin is covered onto the first, second, and third groups of the LED chips  52 ,  53 ,  54 . The wavelength conversion phosphor material  55  can convert into another radiation emission with a different wavelength by absorbing a part of the radiation emission from the third group of the LED chips  54 . The encapsulated resin also has the function of protecting all the LED groups. The first group of the LED chips  52  is formed by the DC-driven AlInGaN-based LEDs, and the individual LED chip of the first group is connected by a bridge for providing an electric connection. 
         [0029]    For example, if an AC-driven positive or negative half wave period is applied to the LED apparatus, the first group of the LED chips  52  can emit a peak wavelength ranging from 510 to 530 nm. However, the second group of the LED chips  53  is formed by the DC-driven InGaPN-based LEDs, and the individual LED chip of the second group is also connected by a bridge for providing an electric connection. If an AC-driven positive or negative half wave period is applied to the LED apparatus, the second group of the LED chips  53  can emit a peak wavelength ranging from 610 to 630 nm. Moreover, the third group of the LED chips  54  is formed by a cascade of a plurality of AlInGaN-based micro-LED chips and constitutes a conventional AC-driven LED chip. As an AC-driven positive or negative half wave period is applied to the third group of the LED chip  54 , it can emit a peak wavelength ranging from 430 to 460 nm. 
         [0030]    Furthermore, the wavelength conversion phosphor material  55  is selected from one of Sr 1−x−y Ba x Ca y SiO 4 :Eu 2+  F, (Sr 1−x−y Eu x Mn y )P 2+z O 7 :Eu 2+  F, (Ba,Sr,Ca)Al 2 O 4 :Eu, ((Ba,Sr,Ca)(Mg,Zn))Si 2 O 7 :Eu, SrGa 2 S 4 :Eu, ((Ba,Sr,Ca) 1−x Eu x )(Mg,Zn) 1−x Mn x ))Al 10 O 17 , Ca 8 Mg(SiO 4 ) 4 Cl 2 :Eu,Mn, ((Ba,Sr,Ca,Mg) 1−x Eu x ) 2 SiO 4 , Ca 2 MgSi 2 O 7 :Cl, SrSi 3 O 8 .2SrCl 2 :Eu, BAM:Eu, Sr-Aluminate:Eu, Thiogallate:Eu, Chlorosilicate:Eu, Borate:Ce,Tb, Sr 4 Al 14 O 25 :Eu, YBO 3 :Ce,Tb, BaMgAl 10 O 17 :Eu,Mn, (Sr,Ca,Ba)(Al,Ga) 2 S 4 :Eu, Ca 2 MgSi 2 O 7 :Cl,Eu,Mn, (Sr,Ca,Ba,Mg) 10 (PO 4 ) 6 Cl 2 :Eu, ZnS:Cu,Al, (Y,Gd,Tb,Lu,Yb)(Al y Ga 1−y ) 5 O 12 :Ce, (Sr 1−x−y−z Ba x Ca y Eu z ) 2 SiO 4 , (Sr 1−a−b Ca b Ba c )Si x N y O z :Eu a , Sr 5 (PO 4 ) 3 Cl:Eu a , and a mixture of any combination of the above, and it converts into a peak wavelength ranging from 550 to 590 nm by absorbing a part of the radiation emission from the third group of the LED chips  54 . The LED apparatus can be directly driven by an AC power source by providing a circuit and a conductive wire to electrically connect the first group of the LED chips  52 , the second group of the LED chips  53 , and the third group of the LED chips  54 . By combining the spectral regions of 430˜460 nm, 510˜530 nm, 550˜590 nm, and 610˜630 nm, the AC-driven white LED apparatus can achieve the properties of high color rendering, high light emitting efficiency and stable chromaticity coordinate. The lead frame  51  of the present invention is selected from one of ceramic based material, aluminum nitride based (AlN-based) material, copper, aluminum, molybdenum, tungsten, and aluminum oxide based (AlO-based) material or mixture of any combination of the above. 
         [0031]    With reference to  FIG. 6  for a schematic view of another LED apparatus structure of the present invention, The LED apparatus comprises a lead frame  61 , a first group of the LED chips  62 , a second group of the LED chips  63 , and a third group of the LED chips  64 , a first phosphor material  65 , a second phosphor material  66 , and one encapsulated resin  67 . The wavelength conversion phosphor materials  65 ,  66  are mixed with the encapsulated resin  67 , and the mixed resin is covered onto the first, second, and third groups of the LED chips  62 ,  63 ,  64 . Wherein the first group of the LED chips  62  is formed by the DC-driven AlInGaN-based LEDs, and the individual LED chip of the first group is connected by a bridge for providing an electric connection. If an AC-driven positive or negative half wave period is applied to the LED apparatus, the first group of the LED chips  62  can emit a green spectral region with a peak wavelength ranging from 510 to 530 nm. However, the second group of the LED chips  63  is formed by the DC-driven InGaPN-based LEDs, and the individual LED chip of the second group is also connected by a bridge for providing an electric connection. If an AC-driven positive or negative half wave period is applied to the LED apparatus, the second group of the LED chips  63  can emit a red spectral region with a peak wavelength ranging from 610 to 630 nm. Moreover, the third group of the LED chips  64  is formed by cascading a plurality of AlInGaN-based micro-LED chips and constitutes a conventional AC-driven LED chip. As an AC-driven positive or negative half wave period is applied to the third group of the LED chips  64 , it can emit a blue spectral region with a peak wavelength ranging from 430 to 460 nm. To further improve the stability of the chromaticity coordinates, a pair of individually separated AC-driven LED chips are provided as the load for the AC power supply and a conductive wire electrically connects the two chips. According to the application of present invention, it is preferable to select the loading voltage of an individual AC-driven LED chip ranges from 75 to 150 volts. 
         [0032]    Furthermore, the first phosphor material  65  is selected from one of Sr 1−x−y Ba x Ca y SiO 4 :Eu 2+ F, (Sr 1−x−y Eu x Mn y )P 2+z O 7 :Eu 2+ F, (Ba,Sr,Ca)Al 2 O 4 :Eu, ((Ba,Sr,Ca)(Mg,Zn))Si 2 O 7 :Eu, SrGa 2 S 4 :Eu, ((Ba,Sr,Ca) 1−x Eu x )(Mg,Zn) 1−x Mn x ))Al 10 O 17 , Ca 8 Mg(SiO 4 ) 4 Cl 2 :Eu,Mn, ((Ba,Sr,Ca,Mg) 1−x Eu x ) 2 SiO 4 , Ca 2 MgSi 2 O 7 :Cl, SrSi 3 O 8 .2SrCl 2 :Eu, BAM:Eu, Sr-Aluminate:Eu, Thiogallate:Eu, Chlorosilicate:Eu, Borate:Ce,Tb, Sr 4 Al 14 O 25 :Eu, YBO 3 :Ce,Tb, BaMgAl 10 O 17 :Eu,Mn, (Sr,Ca,Ba)(Al,Ga) 2 S 4 :Eu, Ca 2 MgSi 2 O 7 :Cl,Eu,Mn, (Sr,Ca,Ba,Mg) 10 (PO 4 ) 6 Cl 2 :Eu, ZnS:Cu,Al, (Y,Gd,Tb,Lu,Yb)(Al y Ga 1−y ) 5 O 12 :Ce, (Sr 1−x−y−z Ba x Ca y Eu z ) 2 SiO 4 , (Sr 1−a−b Ca b Ba c )Si x N y O z :Eu a , Sr 5 (PO 4 ) 3 Cl:Eu a , and the combination of aforementioned phosphor materials. The first phosphor material  65  converts the light emitted by the third group of the LED chips  64  to have a yellow-green spectral region with a peak wavelength ranging from 550 to 590 nm by absorbing a part of the radiation emission therefrom. 
         [0033]    The second phosphor material  66  is selected from one of Sr 1−x−y Ba x Ca y SiO 4 :Eu 2+ F, (Sr 1−x−y Eu x Mn y )P 2+z ,O 7 :Eu 2+ F, (Ba,Sr,Ca)Al 2 O 4 :Eu, ((Ba,Sr,Ca)(Mg,Zn))Si 2 O 7 :Eu, SrGa 2 S 4 :Eu, ((Ba,Sr,Ca) 1−x Eu x )(Mg,Zn) 1−x Mn x ))Al 10 O 17 , Ca 8 Mg(SiO 4 ) 4 Cl 2 :Eu,Mn, ((Ba,Sr,Ca,Mg) 1−x Eu x ) 2 SiO 4 , Ca 2 MgSi 2 O 7 :Cl, SrSi 3 O 8 .2SrCl 2 :Eu, BAM:Eu, Sr-Aluminate:Eu, Thiogallate:Eu, Chlorosilicate:Eu, Borate:Ce,Tb, Sr 4 Al 14 O 25 :Eu, YBO 3 :Ce,Tb, BaMgAl 10 O 17 :Eu,Mn, (Sr,Ca,Ba)(Al,Ga) 2 S 4 :Eu, Ca 2 MgSi 2 O 7 :Cl,Eu,Mn, (Sr,Ca,Ba,Mg) 10 (PO 4 ) 6 Cl 2 :Eu, ZnS:Cu,Al, (Y,Gd,Tb,Lu,Yb)(Al y Ga 1−y ) 5 O 12 :Ce, (Sr 1−x−y−z Ba x Ca y Eu z ) 2 SiO 4 , (Sr 1−a−b Ca b Ba c )Si x N y O z :Eu a , Sr 5 (PO 4 ) 3 Cl:Eu a , and a mixture of any combination of the above. The second phosphor material  66  converts the light emitted by the third group of the LED chips  64  to have a red spectral region with a peak wavelength ranging from 630 to 650 nm by absorbing a part of the radiation emission therefrom. The LED apparatus can be directly driven by an AC power source by providing a circuit and a conductive wire to electrically connect the first group of the LED chips  62 , the second group of the LED chips  63 , and the third group of the LED chips  64 . By combining the spectral regions of 430˜460 nm, 510˜530 nm, 550˜590 nm, 610˜630 nm, and 630˜650 nm, the AC-driven white LED apparatus can achieve the properties of high color rendering, high light emitting efficiency and stable chromaticity coordinate. The lead frame  61  of the present invention is selected from one of ceramic based material, aluminum nitride based (AlN-based) material, copper, aluminum, molybdenum, tungsten, aluminum oxide based (AlO-based) material, and a mixture of any combination of the above. 
         [0034]    With reference to  FIG. 7  for a schematic view of another LED apparatus structure of the present invention, the LED apparatus of this embodiment is the same as the above embodiments. 
         [0035]    Only the first group of the LED chips  62  further includes another DC-driven group of LED chips with a different emission wavelength, the other elements are the same as in  FIG. 6 . For example, it is preferable to combine a fourth DC-driven group of the LED chips  70  with an emission wavelength ranging from 510 to 530 nm and a fifth DC-driven group of the LED chips  71  with an emission wavelength ranging from 460 to 510 nm. 
         [0036]    With reference to  FIG. 8  for a schematic view of another LED apparatus structure of the present invention, the LED apparatus of this embodiment is the same as the above embodiments. Only the third group of the LED chips  64  further includes another AC-driven group of LED chips with a different emission wavelength, the other elements are the same as in  FIG. 6 . For example, it is preferable to combine a sixth AC-driven group of the LED chips  80  with an emission wavelength ranging from 510 to 530 nm and a seventh AC-driven group of the LED chips  81  with an emission wavelength ranging from 430 to 460 nm. However, the phosphor material  82  converts into a red spectral region with a peak wavelength ranging from 630 to 650 nm by absorbing a part of the radiation emission from the seventh group of the LED chips  81 . 
         [0037]    With reference to  FIG. 9A  for a schematic view of an equivalent circuit in accordance with a preferred embodiment of the present invention, the equivalent circuit includes two groups of DC-driven green-LED chips  90  and  91 , a group of DC-driven red-LED chips  92 , and two groups of AC-driven blue-LED chips  93  and  94 . The chips in the groups of  90 ,  91 , and  92  are connected each other with an opposite polarity by the electrodes of two individual chips, as shown in  FIG. 9B . However, the manufacturing method of the groups of AC-driven blue-LED chips  93  and  94  is to form a plurality of micro-LED chips on an insulating substrate and cascade the micro-LED chips by a conductive wire, as shown in  FIG. 9C . If an AC-driven positive half wave period is applied to the LED apparatus, the current flows sequentially from the group  90  to  93 ,  94 , and  91 . However, if an AC-driven negative positive half wave period is applied to the LED apparatus, the current flows sequentially from the group  91  to  94 ,  93 , and  90 . 
         [0038]    With reference to  FIG. 10 , which illustrates the manufacturing flow chart of the LED apparatus manufacturing method of one of the preferred embodiment of the present invention, which includes the following steps: 
         [0039]    S 101 : providing a lead frame; 
         [0040]    S 102 : mounting at least one group of AC-driven micro-LED chips and at least one group of DC-driven LED chips on the lead frame; 
         [0041]    S 103 : electrically connecting the groups of the AC-driven micro-LED chips and the DC-driven LED chips; and 
         [0042]    S 104 : providing a mixed resin comprising at least one phosphor formed over the groups of LED chips. 
         [0043]    In one embodiment, the group of AC-driven micro-LED chips may be composed of AlInGaN-based compound semiconductors, and an active region of the AC-driven micro-LED chips is composed of AlInGaN and InGaN. Further more, the group of DC-driven LED chips may be composed of InGaPN-based compound semiconductors, and an active region of the DC-driven LED chips is composed of InGaPN and AlGaP. The method may further comprise a step of electrically connecting the individual micro-LED chip by a cascading method, and a step of electrically connecting the individual DC-driven LED chip by a bridge method. In addition, the wavelength conversion phosphor may be made of a material selected from a group consisting of Sr1−x−yBaxCaySiO4:Eu2+F, (Sr1−x−yEuxMny)P2+zO7:Eu2+F, (Ba,Sr,Ca)Al2O4:Eu, ((Ba,Sr,Ca)(Mg,Zn))Si2O7:Eu, SrGa2S4:Eu, ((Ba,Sr,Ca)1−xEux)(Mg,Zn)1−xMnx))Al10O17, Ca8Mg(SiO4)4Cl2:Eu,Mn, ((Ba,Sr,Ca,Mg)1−xEux)2SiO4, Ca2MgSi2O7:Cl, SrSi3O8.2SrCl2:Eu, BAM:Eu, Sr-Aluminate:Eu, Thiogallate:Eu, Chlorosilicate:Eu, Borate:Ce,Tb, Sr4Al14O25:Eu, YBO3:Ce,Tb, BaMgAl10O17:Eu,Mn, (Sr,Ca,Ba)(Al,Ga)2S4:Eu, Ca2MgSi2O7:Cl,Eu,Mn, (Sr,Ca,Ba,Mg)10(PO4)6Cl2:Eu, ZnS:Cu,Al, (Y,Gd,Tb,Lu,Yb)(AlyGa1−y)5O12:Ce, (Sr1−x−y−zBaxCayEuz)2SiO4, (Sr1−a−bCabBac)SixNyOz:Eua and Sr5(PO4)3Cl:Eua or a mixture of any combination thereof. 
         [0044]    As the disclosure of the LED apparatus in the present invention, it achieves an AC-driven white LED apparatus with a stable chromaticity coordinate and improves the color rendering and the light emitting efficiency by comprising a group of AC-driven LED chips, a group of DC-driven LED chips, and a wavelength conversion phosphor material. In addition, the LED apparatus of the present invention achieves an AC-driven white LED apparatus with a stable chromaticity coordinate by comprising a group of the AlInGaN-based LED chips, a group of the InGaPN-based LED chips, and a wavelength conversion phosphor material. 
         [0045]    The present invention improves over the prior art and complies with the patent application requirements, and thus is duly filed for patent applications. 
         [0046]    While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.