Abstract:
The present disclosure generally relates to several embodiments of a new illumination device using a plurality of LEDs, the device is designed to better diffuse heat produced from a heating driver circuitry and the LEDs in a way that allows for either the operating or equilibrium temperatures of the heat sensitive elements as part of the device to be subject to less stringent temperature increases and therefore improve the viability and energy performance of the device. The new design includes toroid-shaped external rings for the plurality of LEDs and a middle opening for the driver circuitry. The new design further includes fins and the use of different spaces and openings within the housing to help control the flow of heat by way of thermal conduction, thermal convection, or thermal irradiation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/523,695, filed Aug. 15, 2011. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present disclosure generally relates to an illumination device and, more particularly, to a light emitting diode (“LED”)-based illumination device with improved heat evacuation properties 
       BACKGROUND OF THE INVENTION 
       [0003]    Most lighting applications utilize incandescent or gas-filled bulbs, particularly lighting applications that require more than a low level of illumination. Incandescent bulbs typically do not have long operating lifetimes and thus require frequent replacement. Gas-filled tubes, such as fluorescent or neon tubes, may have longer lifetimes, but operating using dangerously high voltages, are relatively expensive and include hazardous materials such as mercury. Further, both bulbs and gas-filled tubes consume substantial amounts of power. 
         [0004]    In contrast, LEDs are relatively inexpensive, operate at low voltage, and have long operating lifetimes. Additionally, LEDs consume relatively little power, are compact, and do not include toxic substances. These attributes make LEDs particularly desirable and well suited for many applications. 
         [0005]    What is desired are LEDs that produce the greatest amount of light for a fixed rate of energy. The overall efficiency of LEDs is reduced when energy is transformed in heat rather than into light. Although it is known that the brightness of the light emitted by an LED can be increased by increasing the electrical current supplied to the LED, increased current also increases the junction temperature of the LED where the anode and cathode is attached below the semi-transparent (and often colored) epoxy resin tip. Increasing the steady state temperature of the junction of an LED in turn reduces the efficiency and lifetime of the LED as the heated structure&#39;s resistivity is increased. Advances in LED technology have brought increasingly bright LEDs. However, such increased brightness is accompanied by increased heat generation, lower lifetime of the structure generally resulting in a greater need to evacuate heat produced by the LED and other heat generating components to reduce its temperature and in turn increase life expectancy and reduce power consumption. 
         [0006]    Consequently, there exist a need for a solution that helps dissipate and otherwise transferring heat generated by the LEDs and their associated circuitry away from the LEDs themselves to increase the efficiency and lifetime of such products. In addition to optimizing the thermal properties of such an LED lamp or illumination device, there is a need to reduce material costs and to incorporate the foregoing in a lamp or illumination device in a form factor that is similar to that of the PAR style and the GU24 Circline lamps. 
       SUMMARY 
       [0007]    The present disclosure generally relates to several embodiments of a new illumination device using a plurality of LEDs, the illumination device is designed to better diffuse heat produced from a heating driver circuitry and the LEDs in a way that allows for either the operating or equilibrium temperatures of the heat sensitive elements as part of the device to be subject to less stringent temperature increases and therefore improve the viability and energy performance of the device. The new design includes toroid-shaped external rings for the plurality of LEDs and a middle opening for the driver circuitry. The new design further includes fins and the use of different spaces and openings within the housing to help control the flow of heat by way of thermal conduction, thermal convection, or thermal irradiation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The invention will be more readily understood in view of the following description when accompanied by the below figures and wherein like reference numerals represent like elements. 
           [0009]      FIG. 1  illustrates a side view of an LED illumination device in accordance with a first embodiment of the disclosure; 
           [0010]      FIG. 2  illustrates a top view of the LED illumination device of  FIG. 1 ; 
           [0011]      FIG. 3  illustrates a bottom view of the LED illumination device of  FIG. 1 ; 
           [0012]      FIG. 4  illustrates a top view of the LED illumination device of  FIG. 1  without the diffuser coupled to the housing; 
           [0013]      FIG. 5  illustrates a side view of the LED illumination device of  FIG. 4 ; 
           [0014]      FIG. 6  illustrates a side perspective view of the LED illumination device of  FIG. 4 ; 
           [0015]      FIG. 7  illustrates a cross-sectional view of the LED illumination device of  FIG. 1 ; 
           [0016]      FIG. 8  illustrates a top view of the half toroid-shaped circuit boards of the LED illumination device of  FIG. 1 ; 
           [0017]      FIG. 9  illustrates an exemplary layout of the plurality of circuit components associated with the first and second half toroid-shaped circuit boards of the LED illumination device of  FIG. 1 ; 
           [0018]      FIG. 10  illustrates an top exploded view of the LED illumination device of  FIG. 1 ; 
           [0019]      FIG. 11  illustrates a bottom exploded view of the LED illumination device of  FIG. 1 ; 
           [0020]      FIG. 12  illustrates a side view of an LED illumination device in accordance with a second embodiment of the disclosure; 
           [0021]      FIG. 13  illustrates a top view of the LED illumination device of  FIG. 12 ; 
           [0022]      FIG. 14  illustrates a top perspective view of the LED illumination device of  FIG. 12 ; 
           [0023]      FIG. 15  illustrates a bottom perspective view of the LED illumination device of  FIG. 12 ; 
           [0024]      FIG. 16  illustrates a top view of a partially-assembled LED illumination device of  FIG. 12  illustrating the relative placement of the heat sink cap and the half toroid-shaped circuit boards in the trough of the housing; 
           [0025]      FIG. 17  illustrates a side perspective view of the LED illumination device of  FIG. 16 ; 
           [0026]      FIG. 18  illustrates a top view of the half toroid-shaped circuit boards of the LED illumination device of  FIG. 12 ; 
           [0027]      FIG. 19  illustrates a top perspective view of a partially-assembled LED illumination device of  FIG. 12  illustrating the relative placement of the half toroid-shaped circuit boards in the trough of the housing, the inner and outer reflectors and the power supply driver circuitry in the power supply cavity; 
           [0028]      FIG. 20  illustrates a top perspective view of the LED illumination device of  FIG. 19  without the inner and outer reflectors; 
           [0029]      FIG. 21  illustrates a cross-sectional view of the LED illumination device of  FIG. 12 ; and 
           [0030]      FIG. 22  illustrates an exploded view of the LED illumination device of  FIG. 12 . 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding the present disclosure. It will be apparent to one of ordinary skill in the art, however, that these specific details need not be used to practice the present disclosure. In other instances, well-known structures, interfaces and processes have not been shown or de 
         [0032]      FIG. 1  illustrates a side view  100  of an LED illumination device in accordance with a first embodiment of the disclosure. LED illumination device comprises housing  102  having a plurality of heat transfer fins  105 , base plug  104 , diffuser  106  and cap  108 . In one embodiment, housing  102  comprises aluminum alloy 5052. In another embodiment, housing  102  comprises die cast aluminum. Those of skill in the art, however, will appreciate that any other form of metal or metal allow may be substituted for aluminum and/or aluminum alloy 5052 Those of skill in the art will further appreciate that different environments of use will dictate the type of metal or metal alloy used. To help evacuate heat, metal or metal allow is a good conductor and if given the right surface finish will have the required roughness to increase surface natural convection in the air. In one embodiment, as shown, housing  102  is generally circular in nature. It is recognized, however, that housing  102  may take any desired shape such as but not limited to that of a square, oval, rectangle, etc. In the embodiment as shown, the circular housing allows for the LED illumination device  100  to have the same natural air convection coefficient whatever the radial orientation at installation (i.e. offer a 360 deg. symmetry in cooling). 
         [0033]    As illustrated, the exterior sides and base of housing  102  comprise a plurality of fins  105  that protrude radially outward from the center of the base of the housing  102  (as seen in  FIG. 3 ). The plurality of fins  105  assist housing  102  in the thermal transfer of heat from the heat-generating sources associated with the LED illumination device  100  (e.g., the LEDs themselves and driving/power supply circuitry, not shown in this FIG.) to the atmosphere via convection and/or irradiation. The fins  105  increase the contact surface area between the heated housing and the cooler atmospheric or ambient air and create passages for the flow of heating air moving under its own convective force. As shown, the fins  105  are placed both at the circumference of the housing  102  and as part of the radial base between the base plug  104  and the outside periphery of the housing  102 . These fins  105  allow for the flow of convective air if the housing is horizontal, vertical, or in any intermediate orientation. 
         [0034]    Base plug  104  is coupled to the base of the housing  102  using an appropriate fastener as is known in the art on a bottom surface  182  of the housing plate  170 . In one example, base plug  104  may be a GU-24, AC 120 style base. In another embodiment, the housing fastener may accommodate an E-26, AC 120 style base or an E-26 adapter base. In the design as shown at  FIG. 7 , the base plug  104  is connected only a housing plate  170  in conductive contact with one of the two heating sources, the power supply driver circuitry  408 . 
         [0035]    Diffuser  106  is coupled to the housing  102 . In one embodiment diffuser  106  is a snap-on cover that shields the inside components of the LED illumination devices  100  and offers a uniform external appearance. In one embodiment, diffuser  106  is an optic that changes the color or direction of the light emitted from the LED illumination device located between the inside surface of the diffuser  106  and the top surface  171  of the housing  102 . As noted diffuser  106  may snap on to the housing  102  at one or more locations (i.e., using corresponding male and female-shaped components), not shown. Alternatively, diffuser  106  may screw on to threads located on the inside of diffuser  106  and matching threads located on the rim of the housing  102 . One of ordinary skill in the art will appreciate that diffuser  106  may be coupled to housing other known mechanism such as screws, etc. 
         [0036]    In one embodiment, diffuser  106  is toroid-shaped with a centrally located hole that is appropriately sized to receive cap  108 . Cap  108  may be coupled to the diffuser using conventional mechanisms such as snap on devices, matching screw threads and/or screws, etc. In one embodiment, cap  108  is made of any material that allows the heated air located between the housing  102  and the diffuser  106  to dissipate through the cap  108  and is therefore a ventilated cap with air holes. In one embodiment, cap  108  is made of perforated plastic to allow heat to dissipate from the heat-generating sources associated with the LED illumination device into the atmosphere. Cap  108  may be emblazoned with the manufacturer&#39;s name of the LED illumination device or with any other emblem, logo, or image to indicate the source of the product. If there are slits in the diffuser  106  in lieu of a cap  108  or in the event the open volume between the diffuser  106  and the housing  102  must remain air tight, a conductive means helps diffuse the heat outside of the diffuser, such as the use of a heat conductive metal to increase surface temperature and ultimately convection and or irradiation with the environment. 
         [0037]      FIG. 2  illustrates a top view  200  of the LED illumination device  100  of  FIG. 1 . More specifically,  FIG. 2  illustrates diffuser  106  and ventilated cap  108  where the cap  108  is located in the center of the diffuser  106  and is of a rounded shape.  FIG. 3  illustrates a bottom view  300  of the LED illumination device  100  of  FIG. 1 . As discussed above, housing  102  includes a plurality of fins  105  that collectively emanate near the center of the housing base (i.e., near the base plug  104 ), extend radially across the base of the housing and terminate along the circumferential sides of the housing  102  (see  FIG. 1 ). As shown, the fins  105  are part of the housing  102 , but in alternative embodiments, the fins  105  can be of any configuration and geometry including part of a mounted plate to the housing  102 . 
         [0038]      FIG. 4  illustrates a top view  400  of the LED illumination device of  FIG. 1  without the diffuser  106  coupled to the housing  102 . When diffuser  106  is removed from the housing, the interior components of housing  102  and the LED illumination device  100  are exposed to atmospheric air. Housing  102  includes a housing top flange surface  410  that extends as a lip or flange circumferentially around the body of the housing  102 . The center of housing  102  includes a power supply cavity  302  that houses the power supply driver circuitry  408 . Power supply driver circuitry  408 , as is known in the art, comprises any combination of logic. As used herein “logic” may refer to any single or collection of circuits, integrated circuits, processors, transistors, memory, combination logic circuit, or any combination of the above that is capable of providing a desired operation(s) or function(s). For example, logic may take the form of a processor executing instructions from memory or a dedicated integrated circuit. Power supply driver circuitry  408  conditions the electrical current from, for example, 120VAC to the appropriate constant current to accommodate the particular LED array associated with the LED illumination device. 
         [0039]      FIG. 7  illustrates that the first heating source, namely the driver circuitry  408  can be mounted inside of an volume located between the housing  102  and the diffuser  106 . The circuitry  408  is located in an opening  172  created between an inner surface  181  of the support  173  for the toroid-shaped circuit board  402 , an inner surface  174  of the diffuser  106  and a top surface  175  of the housing plate  170  part of the housing  102 . A first gap  185  is created between the external edge  176  of the driver circuitry  408  and the inner surface  171  where only the wire joints  702  bridge this area. The first gap  185  allows for the heat generated by the driver circuitry  408  not to be exchanged via conduction with the LEDs located on the circuit board  402  thus insulating the first heat source with the LEDs acting as a second heating source. 
         [0040]    Heat generated by the driver circuitry  408  can be exchanged by conduction with the housing plate, via convection if there is gas or air within either the first gap  185  or the second gap  177  created between an upper surface  178  of the driver circuitry  408  and the diffuser  106 . For example, a cap  108  can be also designed to help bridge the second gap  177  and serve as heat exchanger to evacuate heat from the driver circuitry  408 . 
         [0041]    As shown at  FIG. 7 , the support  173  for the toroid-shaped circuit board  402  is an area made from conductive metal part of the housing  102  designed to store and transfer calorific energy via conduction from the secondary heating source to the fins  105 . In the example as shown at  FIG. 6 , the heating sources, namely the LEDs and the driver circuitry  408  are distributed as evenly as possible over the volume of the housing to prevent local spikes in heat. The radial and circumferential distribution of the LEDs is also regular and in two or more rows based on the size of the LEDs. Their expected heat generation are radially and circumferentially distributed to create a uniform heat distribution within the entire LED illumination device  100 . 
         [0042]    In addition, first half toroid-shaped circuit board  402  and second half toroid-shaped circuit boards  404  are coupled to the housing top flange surface  410  using any conventional means. In one embodiment, first and second half toroid-shaped circuit boards  402 ,  404  are coupled to the housing top flange surface using screws. In another embodiment, the coupling is made using an adhesive or solder. In one embodiment, circuit boards  402 ,  404  are sized similar to the width of the housing top flange surface  410  and offer some amount of edge relief on both the inner and outer edges of the circuit boards  402 ,  404  with respect to housing top flange surface  410 . 
         [0043]    The first and second half toroid-shaped circuit boards  402 ,  404  include a plurality of LEDs  406 . In one embodiment, the plurality of LEDS  406  are coupled to the top of each circuit board  402 ,  404  in a series circuit configuration. In a preferred embodiment, the first and second half toroid-shaped circuit boards  402 ,  404  are printed circuit boards. In other embodiments, the boards  402 ,  404  are breadboards. The plurality of LEDs  406  may be coupled to the circuit boards  402 ,  404  using surface-mount construction (i.e., soldered on pads or lands on the outer surface of the boards  402 ,  404 ) to form a printed circuit assemblies. One of skill in the art, however, will recognize that the plurality of LEDs  406  may be coupled to the circuit boards  402 ,  404  using other types of construction such as but not limited to through-hole construction. 
         [0044]    The first and second half toroid-shaped circuit boards  402 ,  404  are, in one embodiment, made of 2-sided, 2-ounce per square foot copper board at 0.040 inch in thickness with minimum removal having a base material of FR-4 substrate coated using a white solder mask. In such an embodiment, the copper is maximized to further assist in heat dissipation. One of ordinary skill in the art, however, will appreciate that other types and shapes of boards may also be used in accordance with other embodiments. By constructing the circuit boards  402 ,  404  in half toroid-shaped segments, the disclosure is able to realize lower material and manufacturing costs as compared to a single toroid-shaped board. 
         [0045]      FIG. 5  illustrates a side view  500  of the LED illumination device of  FIG. 4  and illustrates the first half toroid-shaped circuit board  402  sitting atop the housing top flange surface  410  and having plurality of LEDs  406  coupled thereto. 
         [0046]      FIG. 6  illustrates a side perspective view  600  of the LED illumination device of  FIG. 4  and further shows the power supply driver circuit  408  on the same plane as the first and second half toroid-shaped circuit boards  402 ,  404 . In one embodiment, the top of the power supply driver circuit  408  is elevated relative to circuits  402 ,  404  such that the heat generated from the power supply driver circuit  408  emanates outward in the direction of the most heat resistant portion of the light emitter as part of the plurality of LEDs  406  without adversely affecting the micro-electronics and different other heat sensitive portions of the plurality of LEDs  406  themselves. 
         [0047]      FIG. 7  illustrates a cross-sectional view  700  of the LED illumination device of  FIG. 1 .  FIG. 7  illustrates the components generally discussed above with respect to  FIGS. 1-6  and further illustrates wire joint(s)  702  that couples the power supply driving circuit  408  to the first half toroid-shaped circuit board  402 . One or more other wire joints (not shown) may be used to couple the power supply driving circuitry  408  to the second half toroid-shaped circuit board  404 . Wire joint(s) may include any number of suitable grade wire or other conduits for the transfer of electrical current from the power supply driving circuit  408  to the circuit boards  402 ,  404  and their associated plurality of LEDs  406 . 
         [0048]    The distance between top surface  175  of the housing plate  170  and the top flange surface  410  upon which the first and second half toroid-shaped circuit boards  402 ,  404  are placed is smaller than the distance between the top surface  175  of the housing plate and the upper surface  178  of the driver circuitry  408 . In that case, a portion of the radial surface of the driver circuitry  408  is allowed to irradiate heat directly on the heat resistant portion of the LEDs on the housing  102  and not irradiate the heat to the heat sensitive portion of the LEDs. Further, a larger portion of the heat of the driver circuitry  408  can be made to irradiate directly to the diffuser  106  by increasing the visible surfaces between these two elements. 
         [0049]      FIG. 8  illustrates a top view  800  of the half toroid-shaped circuit boards  402 ,  404  of the LED illumination device of  FIG. 1 . As shown, first and second half toroid-shaped circuit boards  402 ,  404  may include through-holes  804  for coupling the circuit  402 ,  404  to the housing top flange surface  410 . For example, a screw may be used to pass through the through-holes and couple the circuit boards  402 ,  404  to the housing top flange surface  410 . First and second half toroid-shaped circuit boards  402 ,  404  further include a plurality of planes  802 , each with equal surface areas. The boundaries of each plane  802  represent the separation of copper within the boards  402 ,  404  and are made by any conventional process such as etching during fabrication of the boards  402 ,  404 , with each trace line representing a separation of copper pad associated with that portion of the circuit board  402 ,  404 . The back side (not shown) of the circuit boards  402 ,  404  may be a mirror image of the front side. 
         [0050]    In one embodiment the electrical current from the power supply driver circuit  408  is coupled to the first and second half toroid-shaped circuit boards  402 ,  404  such that the current first travels to the LEDs  406  located to the left and right of the center through holes  804  (i.e., the through holes located at the upper most location and lower most location relative to the height of the figure) and then travels in series along each of the LEDs  406  located along the outer ring of LEDs  406  on each board  402 ,  404  toward the left and right sides of the boards  402 ,  404 , respectively, and then travels back along the inner ring of LEDs  406  and meet at a mutual common point with the power supply driver circuit  408 . By way of reference to the first half toroid-shaped circuit board  402 , the wire joint(s)  702  (not shown) carries current from the power supply driver circuit  408  to LED C 1  and LED C 11 . LED C 1  is coupled in series with LEDs C 2 -C 10 , and LED C 11  is coupled in series with LEDs C 16 -C 20 . 
         [0051]      FIG. 9  illustrates an exemplary layout of the plurality of planes  802  associated with the first and second half toroid-shaped circuit boards  402 ,  404 . In particular,  FIG. 9  illustrates two identical planes  802  where the lines drawn depict separation of the underlying copper of the boards  402 ,  404 . Each plane  802  includes a heat sink  902  and a plane extension  904 . LEDs are mounted on heat sink  902  and the anodes and cathodes of each LED  406  are coupled to the appropriate plane  802  or plane extension  904 , as the case may be, to connect the circuit. Thus, the planes  802 , together with the plane extensions  904 , collectively permit the flow of current through the LEDs  406 . 
         [0052]      FIG. 10  illustrates a top exploded view  1000  of the LED illumination device of  FIG. 1  and  FIG. 11  illustrates a bottom exploded view  1100  of the LED illumination device of  FIG. 1 , collectively illustrating each of the individual components described in reference to  FIGS. 1-9 . 
         [0053]      FIG. 12  illustrates a side view  1200  of an LED illumination device in accordance with a second embodiment of the disclosure. The LED illumination device of  FIG. 12  includes a housing  1202 , a diffuser  1206 , a heat sink cap  1208 , a plurality of housing fins  1210 , a plurality of cap fins  1212  and a base plug  104 . Housing  1202  is identical to housing  102  of  FIG. 1  in construction but of a different shape. As described below, housing  1202  includes a housing trough for the plurality of LEDs  406 . Housing  1202  includes a plurality of housing fins  1112  that are also identical to the plurality of fins  105  of  FIG. 1  but adapted to fit the sides of housing  1202 . The plurality of housing fins  1112  serve as heat sinks for the heat generated by the LED illumination device of  FIG. 12 . As before, base plug  104  may take the form of an GU-24, E-26 or E-26 adapter style base. Affixed to the top of the housing  1202  is diffuser  1206 , which is also identical to diffuser  106  of  FIG. 1  but of a different shape (as described below with reference to  FIG. 13 ). Thus, diffuser  1206  may be configured as a snap-on element for coupling to the top of the housing  1202 . Finally, LED illumination device of  FIG. 12  includes a heat sink cap  1206  having a plurality of cap fins  1212 . Heat sink cap  1206  and its fins  1212  may be constructed in the same manner as housing  1202  and the plurality of housing fins  1212  and serve as a second heat sink for the LED illumination device of  FIG. 12 . Heat sink cap  1208  may be coupled to housing  1202  using any conventional manner including for example snap on components and matching screw threads. 
         [0054]      FIG. 13  illustrates a top view  1300  of the LED illumination device of  FIG. 12  illustrating heat sink cap  1208 , the plurality of cap fins  1212 , the diffuser  1206  and the optional cap  108 . As before, in one embodiment, cap  108  is ventilated to allow it to better transfer heat from the heat sink cap  1208  to the atmosphere. 
         [0055]      FIG. 14  illustrates a top perspective view  1400  of the LED illumination device of  FIG. 12  and  FIG. 15  illustrates a bottom perspective view  1500  of the LED illumination device of  FIG. 12 . Power supply cavity  302  is illustrated in  FIG. 15  as occupying the area inside housing  1202  generally above the base plug  104  in a similar location as identified in reference to the LED illumination device of  FIGS. 1-11 . 
         [0056]      FIG. 16  illustrates a top view  1600  of a partially-assembled LED illumination device of  FIG. 12  without the diffuser  1206  coupled to the housing  1202  and without any reflector elements (discussed below in  FIG. 19 ).  FIG. 17  illustrates a side perspective view  1700  of the LED illumination device of  FIG. 16 . Collectively,  FIGS. 16 and 17  illustrate the first and second half toroid-shaped circuit boards  1602  and  1604  associated with the LED illumination device. Circuit boards  1602  and  1604  are similar to circuit boards  402  and  404  but only have one row of constituent panels  802  and LEDs  406  (described in reference to  FIG. 18 ) whereas circuit boards  402  and  404  have two rows of panels  802  and LEDs  406 . Further, as illustrated in  FIG. 17 , circuit boards  1602  and  1604  sit in a housing trough or a recessed platform  1606  within housing  1208 . Circuit boards  1602 ,  1604  may be coupled to housing  1202  in the same manner as boards  402 ,  404  are coupled to housing  102 . 
         [0057]      FIG. 18  illustrates a top view  1800  of the first and second half toroid-shaped circuit boards  1602 ,  1604  of the LED illumination device of  FIG. 12 . Like circuit boards  402  and  404 , circuit boards  1602  and  1604  comprise a plurality panels  802  and a plurality of LEDs  406 . 
         [0058]      FIG. 19  illustrates a top perspective view of another partially-assembled LED illumination device of  FIG. 12  without the diffuser  1206  coupled to the housing  1202  and without the heat sink cap  1208 . Outer reflector  1908  and inner reflector  1910 , which may be shaped at 45 degree angles (or any other degree angles) and may be manufactured out of chrome and or plastic, are designed to direct the light emitted from the plurality of LEDs  1802  outwards instead of providing full flood light as the LED illumination device of  FIGS. 1-11  generally provides. Reflectors  1908 ,  1910  may be held in place or coupled to the housing  1202  and/or the first and second half toroid-shaped circuit boards  1602 ,  1604  using a variety of conventional means such as but not limited to adhesives, snap-on components, etc. 
         [0059]      FIG. 19  further illustrates power supply cavity  302 , power supply driving circuit  408  and wire joint(s)  702 .  FIG. 20  illustrates a top perspective view  1900  of the LED illumination device of  FIG. 19  without the outer and inner reflectors  1908 ,  1908 . 
         [0060]      FIG. 21  illustrates a cross-sectional view  2100  of the LED illumination device of  FIG. 12  showing the components discussed above with respect to  FIGS. 12-20  and  FIG. 22  illustrates an exploded view  2200  of the LED illumination device of  FIG. 12  showing the same components. The embodiment as shown at  FIGS. 14-22  and as best illustrated in  FIG. 21  shows how in some configurations the second gap  177  as shown at  FIG. 7  may be replaced by a heat sink cap  1208  having a plurality of heat sink fins  1212  for the diffusion of the heat generated by the driver circuitry  408  directly via conduction through the sink cap  1208  into ambient air via convection. In this embodiment, the second gap  175  has been kept. Several other tools to help better evacuate heat in addition to the housing fins  1210  can also be used like the outer reflector  1908  and the inner reflector  1910 . 
         [0061]    In this second embodiment, an internal ring  1834  may be used and includes a recessed platform  1606  designed for stability, to close the LED area or to protect the LEDs from irradiation from the driver circuitry  408 . The internal ring  1834  as shown includes holes  1835  for the passage of wire joints  702 . 
         [0062]    As discussed above and illustrated in the accompanying drawings, the power supply driver circuitry  408  is placed on the same plane or in front of the LEDs  406 . Among other advantages, the above description of the LED illumination devices include an isolated power supply driver circuitry  408  relative to the half toroid-shaped circuit boards  402 ,  404  and  1602 ,  1604  that allows for a unique lighting form factor with a ring of light while simultaneously optimizing cooling of the power supply driver circuitry  408 . By using the half toroid-shaped circuit boards  402 ,  404  and  1602 ,  1604 , the disclosure optimizes the use of circuit board material and results in lower material and manufacturing costs. 
         [0063]    The foregoing benefits are substantial as compared to conventional PAR lamps. Such conventional PAR lamps are generally cone shaped with LEDs on the base of the cone facing outward with powers supply driver circuitry buried internally within the cone/housing. In such prior art, the temperate of the powers supply driver circuitry is not efficiently dissipated (e.g., to any heat sink devices on the body of the cone) without causing damage to the LEDs. 
         [0064]    Not only does the foregoing disclosure overcome the disadvantage of positing the power supply driver circuitry directly behind the LEDs by the relative placement of the powers supply driver circuitry  408  vis-à-vis the LEDs  408  thereby permitted exposure of heat generated by the powers supply driver circuitry  408  to the atmosphere, but the embodiments discussed herein are low profile like a fluorescent Circline lamp. It is envisioned that the embodiments described in  FIGS. 1-11  and variants thereof may be adopted to replace traditional Circline lamps and the embodiments described in  FIGS. 12-22  may be adopted to replace traditional PAR lamps. 
         [0065]      FIGS. 10 and 22  show two different light emitting diode illumination devices  1000  and  2200  (also described as  100  in other figures) made of a housing  102  or  1202  respectively with an external peripheral ring  85  as shown at  FIGS. 7 and 21  for the support of at least a circuit board  402  or  1602 . These figures also show an inner surface  171 , and a power supply cavity  302  defined in the external peripheral ring  85  by the inner surface  171  and at its base by a housing plate  170  having a top surface  175  in the power supply cavity  302  and a bottom surface  182 , a base plug  104  coupled to the bottom surface  182  of the housing plate. The base plug  104  is capable of receiving power from a conventional power source and transferring the power through the plug  104 . 
         [0066]    The devices  1000  and  2200  respectively also include a power supply driver circuitry  408  coupled to the base plug  104  and connected to the top surface  175  of the housing plate  170  as shown in  FIGS. 7 and 21 . The power supply driver circuitry  408  also includes an external edge  176  at a distance from the inner surface  174  of the housing and results in the creation of a gap  185 . Further, the devices  1000  and  2200  include at least a circuit board  402  or  1602  supported by the external peripheral ring  85  for a plurality of LEDs. As shown at  FIGS. 7 and 21 , to transfer the power from the plug  104  transformed by the circuitry  408  to the LEDs, a series of conductive wire joints  702  are used between the circuit board  402  or  1602 . As shown, the wire joints  702  bridge over the gap  185 . 
         [0067]    As shown the board  402  or  1602  house a plurality of LEDs  406  connected to the circuit board and a diffuser coupled to the housing to shield the plurality of LEDs  406  from the atmosphere. In yet another embodiment, light emitting diode illumination devices  1000  and  2200  include a housing  102  or  1202  with an external peripheral ring  85  as shown at  FIGS. 7 and 21  for the support of at least a circuit board  402  and  1602  and an inner surface  171 , and a power supply cavity  302  defined in the external peripheral ring  85  by the inner surface  171  and at its base by a housing plate  170  having a top surface  175  in the power supply cavity  302  and a bottom surface  182 . 
         [0068]    Further, the devices  1000  and  2200  include a base plug  104  coupled to the bottom surface  182  of the housing plate  170 , the base plug  104  capable of receiving power from a conventional power source and transferring the power through the plug  104  to the driver circuitry  408 . The power supply driver circuitry  408  is also coupled to the base plug  104  and connected to the top surface  175  of the housing plate  170 . The power supply driver circuitry  408  having an external edge  176  at a distance from the inner surface  171  of the housing creating a gap  185 . Finally, the devices  1000  or  2200  include at least a circuit board  402  or  1602  supported by the external peripheral ring  85  for a plurality of LEDs  406  and where an upper surface  178  of the power supply driver circuitry  408  is located above the circuit board  402  and  1602 . 
         [0069]    Other advantages will be recognized by one having ordinary skill in the art. It will also be recognized that the above description describes mere examples and that other embodiments are envisioned and covered by the appended claims. For example, it would be possible to place the power supply driver circuitry  408  on the outside of the housings described above and to place the plurality of LEDs  408  on the inside or toward the center of the housings. It would further be possible to mount the power supply driver circuitry  408  and the plurality of LEDs  408  on the same printed circuit board in either of the arrangements discussed above with minor adaptations while still falling within the scope of the present disclosure. It is therefore contemplated that the present invention cover any and all modifications, variations or equivalents that fall within the spirit and scope of the basic underlying principles disclosed above and claimed herein.