Patent Document

[0001]    This application is a continuation of U.S. application Ser. No. 13/394,205, filed Mar. 5, 2012, which is a National Phase of PCT Patent Application No. PCT/JP2011/004103, filed Jul. 20, 2011 and claims the benefit of Japanese Patent Application No. 2011-047336 filed on Mar. 4, 2011, Japanese Patent Application No. 2010-162504 filed on Jul. 20, 2010. The entire disclosures of the above-identified applications, including the specifications, drawings and claims are incorporated herein by reference in their entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to LED light bulbs including light-emitting devices, and particularly relates to a light bulb shaped LED lamp having a light-emitting diode (LED). 
       BACKGROUND ART 
       [0003]    Compared to conventional illumination light source, semiconductor light emitting devices such as LEDs are small, have high efficiency and long lifetime as a light source. Recent market needs for saving energy and resource boosts the demand for light bulb shaped lamps using LEDs (hereafter simply referred to as “LED light bulb”) and lighting apparatuses including the LED light bulbs. Meanwhile, some manufacturers stop manufacturing incandescent light bulbs using filaments (filament coils). 
         [0004]    For example, the patent literature 1 discloses a conventional LED light bulb reproducing the shape of conventional filament in an incandescent light bulb. In the LED light bulb disclosed in the patent literature 1, an optical fiber resembling the shape of a filament is housed in the globe, an end portion of the LED and the optical fiber are provided near the base, and the light emitted from the LED is coupled to the end portion of the optical fiber. With this configuration, the waves of the light emitted from the LED are guided to the inside of the optical fiber. This reproduces a state as if the filament emits light. 
       CITATION LIST 
     Patent Literature 
       [0005]    [Patent Literature 1] Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2008-515158 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0006]    The incandescent light bulb with the filament that can be seen through the globe is mainly used for decoration. Luminance that allows directly viewing the filament and high luminous flux that would brighten up an area around the light bulb are required for the incandescent light bulb. Accordingly, when replacing the incandescent light bulb with LED light bulb, luminance and luminous flux equivalent to those of the incandescent light bulb are required for the LED light bulb. Higher efficiency and longer lifetime than those of the incandescent light bulb are required for the LED light bulb as well. 
         [0007]    Optical fiber is used in the LED light bulb disclosed in the patent literature 1. This becomes loss in coupling and loss in waveguide when coupling and guiding the light emitted from the LED to the optical fiber, which becomes a bottleneck for increasing efficiency. Furthermore, in order to compensate the coupling loss and waveguide loss for obtaining high luminous flux, it is necessary to increase the luminous flux from the LED which is the light source. However, it is necessary to increase the input power to the LED, which causes reduction in efficiency and lifetime. 
         [0008]    The present invention has been conceived in order to solve these problems, and it is an object of the present invention to provide a light bulb shaped lamp capable of reproducing the simulative light-emission of the filament in the conventional incandescent light bulb emitting light without using optical fibers. 
       Solution to Problem 
       [0009]    In order to solve the problems described above, an aspect of the light bulb shaped lamp according to the present invention is A light bulb shaped lamp comprising: a base board; a light-emitting device mounted on the base board; a base for receiving power from outside; at least two power-supply leads for supplying power to the light-emitting device; and a globe for housing the base board, the light-emitting device, and the power-supply leads, the globe being partially attached to the base, in which the base board is translucent, each of the two power-supply leads is extended from a side of the base toward inside of the globe and is connected to the base board, and the light-emitting device is provided between (i) a portion at which one of the two power-supply leads and the base board are connected and (ii) a portion at which the other of the two power-supply leads and the base board are connected. 
         [0010]    With this configuration, it is possible to implement, using the light-emitting device, a light bulb shaped lamp capable of reproducing the lighting status similar to an incandescent lamp in which the filament can be seen through the globe. 
         [0011]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the base board may be supported by the two power-supply leads. 
         [0012]    With this configuration, it is possible to simplify the component structure. 
         [0013]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, a plurality of the light-emitting devices may be mounted in line, and are covered with a sealing material with translucent property, and
       the sealing material may be formed in line connecting a gap between the light-emitting devices.       
 
         [0015]    With this configuration, it is possible to protect the light-emitting device with the sealing material. Furthermore, by covering the light-emitting device with the translucent material, twinkling light is emitted when the electric bulb shaped lamp is turned on. 
         [0016]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the sealing material may include a wavelength conversion material which absorbs light emitted from the light-emitting device and converts a wavelength of the light into another wavelength. 
         [0017]    With this configuration, a linear shaped light-emitting part is formed, reproducing the lighting status of the filament in the conventional incandescent light bulb when the light bulb shaped lamp is turned on. 
         [0018]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the light-emitting device may not be mounted on a surface of the base board opposite to a surface on which the light-emitting device is mounted, and a second sealing material may be provided on the opposite surface, the second sealing material being provided over, in plan view, the sealing material on the surface on which the light-emitting device is mounted in plan view. 
         [0019]    With this configuration, the light emitted from a surface on which no light-emitting device is mounted (for example, blue light) is converted into another color (for example, converted into yellow light), and a synthesized light such as white light is emitted even from a surface on which no light-emitting device is mounted. 
         [0020]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the sealing material may be in zig-zag shape. 
         [0021]    With this configuration, it is possible to simulate the shape of the filament of the conventional incandescent light bulb. 
         [0022]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, a surface of the base board on which the light-emitting device is mounted may be in a rectangle shape, the two power supply leads may be connected to shorter sides of the rectangle. 
         [0023]    With this configuration, it is possible to simulate the supporting status of the filament part of the conventional incandescent light bulb. 
         [0024]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, a plurality of the light-emitting devices are mounted on at least two surfaces of the base board. 
         [0025]    With this configuration, it is possible to simulate the state of the filament of the conventional incandescent light bulb in which filaments are entwined. 
         [0026]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, two through holes may be formed in the base board, and one of the two power supply leads may pass through one of the two through holes, and the other of the two power supply leads may pass through the other of the two through holes. 
         [0027]    With this configuration, the base board can be firmly connected to the power supply leads. 
         [0028]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the base board may be made of a hard-brittle material having an emissivity of 0.8 or higher. 
         [0029]    With this configuration, it is possible to promote heat dissipation from the base board. 
         [0030]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, the base board may be made of translucent ceramic, and the two power-supply leads are copper wires. 
         [0031]    With this configuration, it is possible to promote heat dissipation from the base board toward the base through the power supply leads. 
         [0032]    Furthermore, in an aspect of the light bulb shaped lamp according to the present invention, an electronic part electrically connected to the light-emitting device may be housed in the base. 
         [0033]    With this configuration, power is appropriately supplied to the light-emitting device. 
         [0034]    Furthermore, an aspect of the light bulb shaped lamp according to the present invention includes a first series-connected group and a second series-connected group each of which is a group of a plurality of the light-emitting devices connected in series, in which the first series-connected group and the second series-connected group are electrically connected in an inverse parallel connection, AC power is supplied to the two power-supply leads, and each of the two power-supply leads is electrically connected to each end of the inverse parallel connection. 
         [0035]    With this configuration, it is possible to cause the filament part to emit light by the AC power without using the diode for rectification. Accordingly, the circuit configuration is simplified. 
       Advantageous Effects of Invention 
       [0036]    The present invention can reproduce the simulated light-emission state of the filament in a conventional incandescent light bulb emitting light. Furthermore, in the present invention, it is not necessary to use optical fibers. Thus, no coupling loss described above occurs, implementing an LED light bulb with high efficiency and high luminous flux. 
         [0037]    Furthermore, since the light-emitting device is covered with the sealing material, the sealing material and the base board becomes the light-emitting unit, thereby implementing an LED light bulb with high efficiency and high luminous flux. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0038]      FIG. 1  is a front view of the LED light bulb according to the embodiment 1 of the present invention. 
           [0039]      FIG. 2A  is a diagrammatic perspective view illustrating the configuration of the filament part in the LED light bulb according to the embodiment 1 of the present invention. 
           [0040]      FIG. 2B  is a cross-sectional view of the filament part in the LED light bulb according to the embodiment 1 of the present invention (cross-sectional view along X-X′ in  FIG. 2A ). 
           [0041]      FIG. 3  is a cross-sectional view for describing the configuration of the LED chip and the peripheral part of the LED chip in the LED light bulb according to the embodiment 1 of the present invention. 
           [0042]      FIG. 4  is a diagram illustrating the circuit configuration of a lighting circuit in the LED light bulb according to the embodiment 1 of the present invention. 
           [0043]      FIG. 5A  is a chart illustrating a light-distribution pattern of the LED light bulb according to the embodiment 1 of the present invention in which a base board made of translucent polycrystalline alumina ceramic (total transmittance of 90% or higher) is used. 
           [0044]      FIG. 5B  is a chart illustrating a light-distribution pattern of the LED light bulb according to a comparative example in which a base board made of opaque alumina ceramic is used. 
           [0045]      FIG. 6A  is a diagrammatic perspective view illustrating the configuration of the filament part in the LED light bulb according to the variation of the embodiment 1 of the present invention. 
           [0046]      FIG. 6B  is a cross-sectional view of the filament part in the LED light bulb according to the variation of the embodiment 1 of the present invention (cross-sectional view along A-A′ in  FIG. 6A ). 
           [0047]      FIG. 7  is a front view of the LED light bulb according to the embodiment 2 of the present invention. 
           [0048]      FIG. 8A  is top view illustrating the configuration of the filament part in the LED light bulb according to the embodiment 2 of the present invention. 
           [0049]      FIG. 8B  is a diagram illustrating the arrangement of a sealing material in the filament part of the LED light bulb according to the embodiment 2 of the present invention. 
           [0050]      FIG. 9  is a diagram illustrating the circuit configuration of a lighting circuit in the LED light bulb according to the embodiment 2 of the present invention. 
           [0051]      FIG. 10  is a diagram (diagrammatic perspective view) for describing the variation  1  of the filament part of the LED light bulb according to the embodiment 2 of the present invention. 
           [0052]      FIG. 11  is a diagram (diagrammatic perspective view) for describing the variation  2  of the filament part of the LED light bulb according to the embodiment 2 of the present invention. 
           [0053]      FIG. 12  is a diagram (diagrammatic perspective view) for describing the variation  3  of the filament part of the LED light bulb according to the embodiment 2 of the present invention. 
           [0054]      FIG. 13  is a diagram (top view) for describing the variation  4  of the filament part of the LED light bulb according to the embodiment 2 of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0055]    The following shall describe the light bulb shaped lamp according to the embodiment of the present invention with reference to the drawings. However, the present invention is determined based on the recitation in Claims. Accordingly, among the components in the following embodiments, the components not recited in the independent claim which illustrates the most generic concept of the present invention are not necessary for solving the problem of the present invention but included as a part of a preferable embodiment. Note that, the diagrams are schematic diagrams, and illustration is not necessarily strictly accurate. 
       Embodiment 1 
       [0056]    First, the light bulb shaped lamp according to the embodiment 1 of the present invention shall be described. The light bulb shaped lamp according to the embodiment 1 of the present invention is a light bulb shaped lamp in which LED is used as the light source, and is the LED light bulb replacing conventional light bulb shaped lamp such as incandescent light bulbs and light bulb shaped fluorescent lamps. 
         [0057]    (Overall Configuration of LED Light Bulb) 
         [0058]    The overall configuration of the LED light bulb according to the embodiment 1 of the present invention shall be described with reference to  FIG. 1 .  FIG. 1  is a top view of the LED light bulb according to the embodiment 1 of the present invention. 
         [0059]    As illustrated in  FIG. 1 , the LED light bulb  1  according to the embodiment 1 of the present invention uses LED chips which are semiconductor light-emitting devices as the light source. The LED light bulb  1  includes a filament part  100  composed of the LED chips and other parts, two power supply leads  140  ( 141  and  142 ) for supplying power to the LED chips, a stem  160 , a globe  170 , a circuit  180  including electronic parts, and a base  190 . The filament part  100  is composed of the LED chips  110  (not illustrated) and a base board  120 . Note that, in  FIG. 1 , the circuit  180  and the power supply leads  140  placed inside the base  190  are illustrated in dotted lines. 
         [0060]    The filament part  100  is a light-emitting unit (light-emitting module) reproduces the simulated light-emitting property equivalent to the filament in an incandescent light bulb, and emits light with the power supplied from the power supply leads  140 . The filament part  100  includes a translucent base board  120  on which the LED chips are mounted, and is housed in the globe  170 . In the embodiment 1, the filament part  100  is suspended approximately at the center of the hollow globe  170 . As described above, placing the filament part  100  at the center of the globe  170  achieves light-distribution property closely similar to the incandescent light bulb using conventional filament coil when the lamp is turned on for light emission. 
         [0061]    In addition, the filament part  100  is suspended in the globe  170  with the support of the two power supply leads  140  ( 141 ,  142 ) at the ends of the base board  120 . More specifically, the filament part  100  is off the inner surface of the globe  170  in the globe  170 . The two power supply leads  140  are supported by the stem  160 . The opening  171  of the globe  170  is closed by the stem  160 . The base  190  is attached to hide the closed part. The circuit  180  is housed in the base  190 . The two power supply leads  140  ( 141 ,  142 ) extend from the stem  160  to outside of the globe  170 , and are connected to the circuit  180 . Among the two power supply leads  140  ( 141 ,  142 ) connecting the circuit  180  and the base  190 , one of the power supply leads  141  is electrically connected to a screw part  191  on the side surface of the base, and the other power supply lead  142  is electrically connected to the eyelet  192  at the bottom of the base. The following is the more detailed description of the components of the LED light bulb  1  according to the embodiment 1. 
         [0062]    (Filament Part) 
         [0063]    First, the filament part  100  shall be described with reference to  FIGS. 2A and 2B .  FIG. 2A  is a diagrammatic perspective view of the filament part in the LED light bulb according to the embodiment 1 of the present invention, and  FIG. 2B  is a cross-sectional view of the filament part along X-X′ in  FIG. 2A . 
         [0064]    As illustrated in  FIGS. 2A and 2B , the filament part  100  includes a plurality of LED chips  110 , a base board  120  on which the LED chips  110  are mounted, and a sealing material  130  for sealing the LED chips  110 . 
         [0065]    The base board  120  is a mounting base board for mounting the LED chips  110 , and is a long board having a first main surface  125  (front surface) composing the surface on which the LED chips  110  are mounted and a second main surface  126  (back surface) composing the surface opposite to the first main surface. A plurality of the LED chips  110  are arranged in a straight line and mounted on the first main surface of the base board  120 . The filament part  100  is placed with the first main surface on which the LED chips  110  are mounted facing toward the top of the globe  170 . 
         [0066]    The base board  120  is composed of a material translucent to visible light. The base board  120  is preferably made of a material with high light transmittance. With this, the light emitted from the LED chip  110  transmits inside the base board  120 , and is emitted from a part in which no LED chip  110  is mounted. Accordingly, even when the LED chips  110  are mounted only on the first main surface of the base board  120 , the light is emitted from the second main surface  126  and other parts. Thus, it is possible to omnidirectionally emit light from the filament part  100  as the center. 
         [0067]    The base board  120  may be made of inorganic material or resin material, and a translucent ceramic board made of alumina or aluminum nitride, a translucent glass substrate, or a flexible substrate made of flexible translucent resin may be used, for example. The base board  120  according to the embodiment 1 is made of ceramic composed of translucent polycrystalline alumina, and is a bar-shaped cuboid 20 mm long, 1 mm wide, and 0.8 mm thick. Accordingly, the shape of the first main surface  125  and the second main surface  126  of the base board  120  is a rectangle with a large aspect ratio. As described above, by making the shape of the base board  120  long, it is possible to reproduce the filament of the incandescent light bulb simulated more closely. Note that, the shape and the size of the base board  120  are examples, and may be in other form or size. 
         [0068]    Power supply terminals  121  and  122  for fixing the power supply leads  140  ( 141 ,  142 ) are provided at both ends of the base board  120  in the longer direction, and metal plating made of gold and others is made on the uppermost surface of the power supply terminals  121  and  122 . At the power supply terminals  121  and  122  on the ends of the filament part  100 , the tip of the power supply leads  140  are electrically and mechanically connected by solder. More specifically, the two power supply leads  140  ( 141  and  142 ) are connected to the shorter sides of the first main surface  125  of the rectangle. In the embodiment 1, the base board  120  is attached to the power supply leads  140  such that the first main surface  125  on which the LED chips  110  are mounted faces the top of the globe  170  (in a direction that the second main surface  126  faces the base). In addition, wire bonding pads  123  and  124  electrically connected to the power supply terminals  121  and  122  are provided on both ends of the first main surface  125  of the base board  120 . 
         [0069]    Twelve LED chips  110  are provided in a straight line between the power supply terminals  121  and  122  on the first main surface  125  of the base board  120 . More specifically, the LED chips  110  are provided between a part at which the power supply lead  141  and the base board  120  are connected and a part at which the power supply lead  142  and the base board  120  are connected. 
         [0070]    Note that, the base board  120  is preferably made of a material which is not only translucent but also has high heat conductivity and heat emissivity for increasing the heat radiation property. In this case, it is preferable that the base board  120  is made of a material generally referred to as a hard brittle material, such as glass and ceramic. Here, the emissivity is represented by a ratio with respect to heat emission on black body (full radiator), and has a value between 0 and 1, with 1 being the value of black body radiation. The emissivity of glass or ceramic is 0.75 to 0.95, and heat emission close to the black body radiation is achieved. In terms of practical use, the emissivity of the base board  120  is preferably 0.8 or higher, and is more preferably 0.9 or higher. In addition, when the volume of the filament part  100  is small compared to the entire lamp and the heat capacity is small, it is preferable to have a configuration with high emissivity so as to dissipate heat. 
         [0071]    Next, the detailed description of the LED chip  110  shall be made with reference to  FIG. 3 .  FIG. 3  is a cross-sectional view for illustrating the LED chip and the configuration around the LED chip in the LED light bulb according to the embodiment 1 of the present invention. 
         [0072]    As illustrated in  FIG. 3 , the LED chip  110  includes a sapphire board  111  and a plurality of nitride semiconductor layers  112  stacked on the sapphire board  111  and each having a different composition, is vertically long, and is 600 μm long, 300 μm wide, and 100 μm thick. At an end of the LED chip on a surface opposite to the sapphire board  111 , a cathode electrode  113 , an anode electrode  114 , and wire bonding parts  115  and  116  are formed. 
         [0073]    The LED chip  110  is fixed with the chip mounting part  119  (see  FIG. 2B ) of the base board  120  by a translucent chip bonding material  118  such that the surface on the sapphire board  111  faces the first main surface  125  of the base board  120 . Silicone resin containing a filler made of metal oxide may be used as the chip bonding material  118 . Note that, using translucent material as the chip bonding material  118  reduces the loss of light emitted from the surface of the LED chip  110  on the sapphire board  111  side and side surfaces of the LED chip  110 , and prevents a shadow blocked by the chip bonding material  118 . In addition, the LED chips  110  are electrically connected by a gold wire  117 . With this, the 12 LED chips  110  are connected in series. The LED chips  110  at the ends of the LED chips  110  connected in series are electrically connected the wire bonding pad parts  123  and  124  that are electrically connected by the gold wire  117  to the feeder terminals  121  and  122  provided at the ends of the base board  120 . Note that, in the embodiment 1, one power supply terminal  121  is a cathode power supply terminal, and the other power supply terminal  122  is an anode power supply terminal. 
         [0074]    The LED chip  110  according to the embodiment 1 is a bare chip which emits visible light in one color, and a blue LED chip which emits blue light when energized may be used, for example. Note that, in the embodiment 1, an example in which 12 LED chips  110  are mounted is illustrated. However, the number of the LED chips  110  may be determined appropriately depending on the usage. For example, as a replacement for a miniature light bulb, only one LED chip may be used. 
         [0075]    The LED chips  110  and the gold wire  117  are covered with the translucent sealing material  130  in a straight line shape. The sealing material  130  is a phosphor containing resin made of a resin containing phosphor particles which are wavelength conversion material, and converts the wavelength (converts color) of light emitted from the LED chip  110  to light with another wavelength, and seals the LED chip  110  for protecting the LED chip  110 . In the embodiment 1, the sealing material  130  is formed in a straight line shape covering all of the LED chips  110  arranged in a straight line. 
         [0076]    More specifically, translucent resin such as silicone resin may be used as the sealing material  130 , and the sealing material  130  is composed of the translucent resin dispersed with phosphor particles (not illustrated) and light-diffusion material (not illustrated). The sealing material  130  with the configuration described above is formed by the following two processes, for example. First, in the first process, the sealing material  130  which is an uncured paste including the wavelength conversion material is applied in a continuous straight line on the row of the LED chips  110  by a dispenser. Next, in the second process, the applied paste of sealing material  130  is cured. The cross-section of the sealing material  130  formed as described above is dome-shaped, and is 1 mm wide and 0.2 mm high. Note that, it is preferable that the width of the sealing material  130  is approximately the same as the width of the base board  120 . 
         [0077]    Note that, the wavelength conversion material included in the sealing material  130  may be a yellow phosphor such as (Sr, Ba) 2 SiO 4 :Eu 2+ , Sr 3 SiO 5 :Eu 2+ , for example. Alternatively, the wavelength conversion material may be a green phosphor such as (Ba, Sr) 2 SiO 4 :Eu 2+ , Ba 3 Si 6 O 12 N 2 :Eu 2+ . Alternatively, the wavelength conversion material may be a red phosphor such as CaAlSiN 3 :Eu 2+ , Sr 2 (Si, Al) 5 (N, O) 8 :Eu 2+ . The sealing material  130  may not be necessarily be made of silicone resin, and may be made of an organic material such as fluorine series resin or an inorganic material such as a low-melting-point glass or a sol-gel glass. Since the inorganic materials are more highly resistant to heat than the organic material, the sealing material  130  made of Inorganic material is advantageous for increasing luminance. 
         [0078]    As phosphor particles, when the LED chip  110  is a blue LED chip which emits blue light, a material which absorbs part of the blue light and converts the wavelength of the light into another wavelength is used. For example, YAG series yellow phosphor particles such as (Y, Gd) 3 Al 5 O 12 :Ce 3+ , Y 3 Al 5 O 12 :Ce 3+  may be used in order to obtain white light from the blue light. With this, part of the blue light emitted from the LED chip  110  is converted into yellow light by wavelength conversion of the yellow phosphor particles included in the sealing material  130 . The blue light which is not absorbed by the yellow phosphor particles and the yellow light obtained by the wavelength conversion of the yellow phosphor particles are diffused and mixed in the sealing material  130 , and is emitted as white light from the sealing material  130 . 
         [0079]    Particles such as silica are used as the light diffusion material. In the embodiment 1, the translucent base board  120  is used. Thus, the white light emitted from the line-shaped sealing material  130  transmits the inside of the base board  120 , and is emitted from the back surface and the side surfaces of the base board  120 . As described above, the sealing material  130  including the wavelength conversion material is arranged in line on one of the main surfaces of the bar-shaped base board  120 . Thus, the base board  120  appears shining like a filament of the conventional incandescent light bulb from any surface of the base board  120  when the light bulb shaped lamp  1  is turned on. 
         [0080]    In addition, the sealing material  130  including the wavelength conversion material may be arranged on a surface of the base board  120  on which the LED chip  110  is not mounted. More specifically, as in the embodiment 1, in a configuration in which the LED chip  110  is mounted on the first main surface  125  of the base board  120  and the LED chip  110  is not mounted on the second main surface  126  opposite to the first main surface  125 , the sealing material  130  (the second sealing material) is formed on the second main surface  126 , in addition to the sealing material  130  (first sealing material) on the first main surface. With this, the blue light emitted from the second main surface  126  on which the LED chip  110  is not mounted is converted into yellow light and white light is synthesized. Accordingly, it is possible to set the color of light emitted from the second main surface  126  on which the LED chip  110  is not mounted closer to the color of light directly emitted from the sealing material  130  on the first main surface  125 , allowing emission of white light from both surfaces of the base board  120 . As a result, a light-distribution property even more closely similar to the incandescent light bulb can be achieved. 
         [0081]    In this case, it is preferable that the sealing material  130  formed on the second main surface  126  is formed over, in plan view, the sealing material  130  formed on the first main surface  125  (in a direction orthogonal to the first and second main surfaces). With this, it is possible for the light from the LED chip to effectively enter the sealing material  130  on both of the main surfaces. 
         [0082]    Note that, the wavelength conversion material included in the sealing material  130  may be a yellow phosphor such as (Sr, Ba) 2 SiO 4 :Eu 2+ , Sr 3 SiO 5 :Eu 2+ , for example, in addition to the YAG phosphor. Alternatively, a green phosphor such as (Ba, Sr) 2 SiO 4 :Eu 2+ , Ba 3 Si 6 O 12 N 2 :Eu 2+  may also be used. Alternatively, a red phosphor such as CaAlSiN 3 :Eu 2+ , Sr 2 (Si, Al) 5 (N, O) 8 :Eu 2+  may be used. 
         [0083]    The sealing material  130  may not be necessarily be made of silicone resin, and an organic material such as fluorine series resin or an inorganic material such as a low-melting-point glass or a sol-gel glass may be used as the sealing material other than the silicone resin. Since the inorganic materials are more highly resistant to heat than the organic material, the sealing material  130  made of inorganic material is advantageous for increasing luminance. 
         [0084]    (Power Supply Leads and Stem) 
         [0085]    The two power supply leads  140  ( 141  and  142 ) are power supply wires for supplying power to cause the LED chip  110  in the filament part  100  to emit light. Each of the power supply leads  141  and  142  is a composite wire including an internal lead wire, a Dumet wire and an external lead wire joined in this order. The two power supply leads  141  and  142  have strength enough to support the filament part  100 , and support the filament part  100  such that the filament part  100  is suspended at a constant position in the globe  170 . 
         [0086]    In each of the power supply leads  141  and  142 , the internal lead wire is an electric wire extending to the inside of the globe  170 , and is extended from the stem  160  toward the filament part  100 . The external lead wire is an electric wire extending to outside of the globe  170 , and is extended from the circuit  180  toward the stem  160 . Metal wire mainly containing copper (copper wire) may be used as the internal lead wire and the external lead wire. The Dumet wire is an electric wire sealed inside of the stem  160 . The internal lead wire is connected to the power supply terminals  121  and  122  on the base board  120 , and the external lead wire is connected to the output terminal  182  in the circuit  180  which shall be described later. 
         [0087]    The stem  160  is provided from the opening  171  of the globe  170  toward the inside of the globe  170 . More specifically, the stem  160  is formed as a rod-shaped extending part having one end extended in the proximity of the filament part  100 . More specifically, the stem  160  according to the embodiment 1 is a component with a shape as if the stem used for conventional incandescent light bulb is extended toward the inside of the globe  170 . Note that, the stem  160  may be a stem used for a common incandescent light bulb. 
         [0088]    The end portion of the stem  160  on the base side is joined to the opening  171  of the globe  170  so as to close the opening  171 . As described above, part of the each of the power supply leads  141  and  142  are sealed in the stem  160 . As a result, the filament part  100  inside of the globe  170  is electrically connected to the circuit  180  outside, while keeping the globe  170  airtight. Accordingly, with the LED light bulb  1 , it is possible to prevent water or vapor from entering the globe  170  for a long period of time, and to prevent degradation of the components of the filament part  100  or degradation of the connecting part of the filament part  100  and the power supply leads  140  due to moisture. Note that, each of the power supply leads  140  are not necessarily a composite wire, but a single wire composed of a single metal wire. 
         [0089]    The stem  160  is made of soft glass transparent to visible light. With this, the LED light bulb  1  can prevent the loss of light emitted from the filament part  100  due to the stem  160 . The LED light bulb  1  can also prevent the shadow formed by the stem  160 . Furthermore, white light emitted from the filament part  100  illuminates the stem  160 . Thus, the light bulb shaped lamp  1  can achieve visually superior appearance. Note that, the stem  160  may not have to close the opening  171  in the globe  170 , and may be attached to a part of the opening  171 . 
         [0090]    Note that, the power supply lead  140  is preferably metal wire containing copper with high heat conductivity. With this, it is possible to actively dissipate heat generated at the filament part  100  to the base  190  through the power supply lead  140 . Furthermore, in the embodiment 1, an example in which two power supply leads  140  are included is illustrated. However, it is not limited to this example. For example, when multiple filament parts are housed in the globe and power is supplied to each of the filament parts, each of the filament parts may be supported by separate power supply lead. Note that, each of the power supply leads  140  are not necessarily a composite wire, but a single wire composed of a single metal wire. 
         [0091]    (Globe and Stem) 
         [0092]    The globe  110  has a shape with one end closed in a spherical shape, and the other end has the opening  171 . In other words, the shape of the globe  170  is that the opening  171  provided in a part of hollow sphere is narrowed down while extending away from the center of the sphere. In the embodiment 1, the shape of the globe  170  is Type A (JIS C7710) which is the same as a common incandescent light bulb. 
         [0093]    The globe  170  is a hollow translucent component which houses the filament part  100  inside, and emits the light emitted from the filament part  100  to outside of the lamp. In the embodiment 1, the globe  170  is a hollow glass bulb made of transparent silica glass, and the filament part  100  arranged at the center of the globe  170  can be seen from outside of the globe  170 . With this configuration, the loss of the light emitted from the filament part  100  due to the globe  170  can be suppressed. In addition, with the filament part  100  arranged at the center of the spherical globe  170 , the omnidirectional light-distribution property is achieved when the light bulb shaped lamp  1  is turned on. 
         [0094]    Note that, the shape of the globe  170  does not have to be Type A. For example, the shape of the globe  170  may be Type G or Type E, and may be appropriately selected depending on the usage. The globe  170  does not have to be transparent, and diffusion treatment such as a milky white diffusion film formed by applying silica may be performed. Alternatively, the globe  170  may be colored in red, yellow, or other colors, or a pattern or picture may be drawn thereon. Alternatively, the globe  170  does not have to be made of silica glass. The globe  170  may be made of transparent resin such as acrylic. Forming the globe  170  with glass as described above allows the globe  170  to be highly resistant to heat. 
         [0095]    (Circuit and Base) 
         [0096]    The circuit  180  is a lighting circuit for causing the LED chip  110  in the filament part  100  to emit light, and is housed in the base  190 . More specifically, the circuit  180  includes a plurality of circuit elements and a circuit board on which the circuit elements are mounted. In the embodiment 1, the circuit  180  converts the AC power received from the base  190  into the DC power, and the DC power is supplied to the LED chip  110  through the two power supply leads  140 . 
         [0097]      FIG. 4  is a diagram illustrating the circuit configuration of the lighting circuit in the LED light bulb according to the embodiment 1 of the present invention. As illustrated in  FIG. 4 , the circuit  180  in the embodiment 1 includes, as electronic parts (circuit elements), a diode bridge  183  for rectification, a capacitor  184  for smoothing, and a resistor  185  for adjusting current. 
         [0098]    Here, input terminals of the diode bridge  183  are input terminals  181  of the circuit  180 , and an end of the capacitor  184  and an end of the resistor  185  are output terminals  182  of the circuit  180 . Furthermore, the input terminals  181  are electrically connected to the base  190 . More specifically, one of the input terminals  181  is connected to the screw part  191  on the side surface of the base, and the other of the input terminals  181  is connected to the eyelet  192  at the bottom of the base. The output terminals  182  of the circuit  180  are connected to the external lead wire of the power supply lead  140 . More specifically, the output terminals  182  are electrically connected to a row of LED chips  186  (series-connected group) including the LED chips  110  connected in series. 
         [0099]    Note that, the LED light bulb  1  does not have to include the circuit  180 . For example, when the DC power is directly supplied from a lighting equipment or a cell, the LED light bulb  1  does not have to include the circuit  180 . In this case, one of the external lead wires is connected to the screw part  191 , and the other of the external lead wires is connected to the eyelet  192 . Note that, the circuit  180  is not limited to a smoothing circuit, but may be an appropriately selected combination of a light-adjusting circuit, a voltage booster, and others. 
         [0100]    The base  190  is provided at the opening  171  of the globe  170 . More specifically, the base  190  is attached to the globe  170  using an adhesive such as cement to cover the opening  171  of the globe  170 . In this embodiment, the base  190  is an E26 base. The LED light bulb  1  is attached to a socket for E26 base connected to the commercial AC power source for use. 
         [0101]    Note that, in the embodiment 1, an example using an E26 base is described. However, it is not limited to this example, and the size and the shape of the base may be appropriately selected depending on the usage. For example, an E17 base or others may be used as the base  190 . In addition, the base  190  does not have to be a screw base, and may be a base in a different shape such as a plug-in base. Alternatively, the base  190  is directly attached to the opening  171  of the globe  170 . However, it is not limited to this example. The base  190  may be indirectly attached to the globe  170 . For example, the base  190  may be attached to the globe  170  through resin components such as a resin case. In this configuration, the circuit  180  and others may be housed in the resin case, for example. 
         [0102]    (Light Distribution Pattern) 
         [0103]    Next, as an example of the effects achieved by the base board  120  in the LED light bulb  1  according to the embodiment 1 of the present invention, light-distribution patterns of the LED light bulbs shall be described with reference to  FIGS. 5A and 5B .  FIG. 5A  is a chart illustrating a light-distribution pattern of the LED light bulb  1  according to the embodiment 1 of the present invention in which a base board made of translucent polycrystalline alumina ceramic having a total transmittance of 90% or higher is used.  FIG. 5B  is a chart for comparison with  FIG. 5A , and illustrates a light-distribution pattern of the LED light bulb according to a comparative example in which a base board made of opaque alumina ceramic is used. Note that, the configurations of the LED light bulbs used for the charts in  FIGS. 5A and 5B  are identical to the embodiment 1 except for the material composing the base board. In both charts, the light intensity is normalized using the light intensity of an angle having the highest emission intensity. Zero degree is directed toward the globe, and 180 degrees are directed toward the base. In this configuration, since the light is blocked by the metal base, no light is emitted to the 180-degree direction toward the base. Usually, an LED light bulb is attached to the ceiling. In this case, the globe is on the lower side, and the base is on the upper side (ceiling side). 
         [0104]    According to the light-distribution pattern of the LED light bulb  1  according to the embodiment 1 using a translucent base board illustrated in  FIG. 5A , the light from the LED light bulb  1  is strongly emitted in the 20-degree direction on the globe side and 150-degree direction on the base side, which indicates a wide distribution angle of light. In contrast, according to the light-distribution pattern of the LED light bulb according to a comparative example using an opaque base board illustrated in  FIG. 5B , the light from the LED light bulb is strongly emitted in 0-degree direction on the globe side. However, the light is sparsely emitted toward the 150-degree direction on the base side, and the intensity of the light is merely approximately 20% of the highest intensity. Furthermore, an emission angle set to be an angle at which the intensity of light is half the highest intensity is approximately 110 degrees in the light emitted from the LED light bulb in  FIG. 5A , and is narrow in the radiation angle of the light emitted from the LED light bulb in  FIG. 5B , at approximately 70 degrees. As described above, the LED light bulb in  FIG. 5A  can achieve wider light distribution angle than the distribution angle of the LED light bulb in  FIG. 5B , and a light-distribution pattern closer to that of the incandescent light bulb with which the filament can be seen from any direction is achieved. Note that, the direction at which the emission intensity on the globe side of the LED light bulb in  FIG. 5A  should be 0 degree, but is 20 degrees. This is probably because the base board  120  is slightly tilted. 
         [0105]    (Variation of Filament Part) 
         [0106]    Next, a variation of the LED light bulb according to the embodiment 1 of the present invention shall be described with reference to  FIGS. 6A  and  6 B.  FIG. 6A  is a diagrammatic perspective view of the filament part in the LED light bulb according to the variation of the embodiment 1 of the present invention.  FIG. 6B  is a cross-sectional view of the filament part in the LED light bulb along A-A′ in  FIG. 6A . 
         [0107]    The LED light bulb according to this variation is different from the LED light bulb according to the embodiment 1 in the configuration of the filament part, and the rest of the configuration is identical. Accordingly, in this variation, the filament part  200  shall be mainly described. The filament part  200  according to the variation includes a translucent tabular base board  220  and a plurality of rows of LED chips  210 . 
         [0108]    In this variation, the base board  220  is composed of ceramic made of aluminum nitride, and is a tabular board which is a rectangle 20 mm long, 10 mm wide, and 0.8 mm thick. Two through holes  221  and  222  are provided in the base board  220 . The two through holes  221  and  222  are provided at the diagonal ends of the base board  220 , and the power supply leads  140  ( 141  and  142 ) passes through the two respective through holes and fixed with solder. More specifically, the power supply lead  141  passes through one of the through holes  221 , and the power supply lead  142  passes through the through hole  222 . The leads and the through holes are electrically and mechanically connected with solder. 
         [0109]    Furthermore, 30 LED chips  210  which emit violet light are mounted on the first main surface  225  of the base board  220 . The LED chip  210  is composed as three rows of LED chip rows, and one LED chip row includes 10 LED chips  210 . A part of the metal line pattern  223  plated with gold on the surface is a chip mounting part. The LED chip  210  in the variation is mounted by a process known as flip chip bonding with which the cathode electrode and the anode electrode of the LED chip  210  are connected to the chip mounting part. Each of the 10 LED chips  210  included in a row is connected in series, and the three rows are connected in series with one another. In other words, all of the 30 LED chips  210  are connected in series. Note that, the metal line pattern  223  may be formed using a transparent conductive material such as indium tin oxide (ITO). By having the metal line pattern  223  made of a transparent conductive material allows reducing the loss due to light absorption compared to the case in which the light-blocking metal material is used. In addition, the shadow caused by blocked light does not appear either. 
         [0110]    Each of the rows of LED chips of the LED chips  210  is sealed in line by the sealing material  230  including the wavelength conversion material. With this, it is possible to reproduce the LED light bulb as if there are three filaments. In this variation, the aluminum nitride composing the base board  220  is clear and transparent. Thus, when viewed from the second main surface  226  side opposite to the first main surface  225  on which the LED chip  210  is mounted, it is possible to view the shape of the sealing material  230  clearly. As in this variation, since the filament part is composed of a plurality of LED chip rows (series connected group), each row can be easily recognized from an opposite main surface side on which the LED chips are not mounted. 
         [0111]    Note that, when the LED chip  210  which emits violet light is used as in this variation, the filament part  200  which emits white light can be achieved by using blue phosphor, green phosphor, and red phosphor as the wavelength conversion material included in the sealing material  230 . 
         [0112]    In addition, the power supply leads  140  support the filament part  200  at the diagonal parts of the base board  220  in a square in this variation. However, it is not limited to this example. Alternatively, the filament part  200  may be supported at the central part of opposite two sides of the rectangle base board  220 , or supported at the both ends of one side. In particular, when the base board  220  is placed vertically facing the main surface of the base board on which the LED chip is mounted toward the side part of the globe  170 , the part supporting the base board  220  is located at the stem side. Thus, it is possible to shorten the length of the power supply lead  140 . 
       Embodiment 2 
       [0113]    Next, an LED light bulb  2  according to the embodiment 2 of the present invention shall be described with reference to  FIGS. 7 to 9 .  FIG. 7  is a front view of the LED light bulb according to the embodiment 2 of the present invention. 
         [0114]    As illustrated in  FIG. 7 , the LED light bulb  2  according to the embodiment 2 of the present invention is different form the LED light bulb  1  according to the embodiment 1 in that a spherical (Type G) globe  370  is used, that the LED chips  310  are mounted on both surfaces of the base board  320 , and that the two rows of LED chips (series connected group) that were connected in series are inversely connected in parallel. 
         [0115]      FIG. 8A  is a top view of the filament part  300  in the embodiment 2. The filament part  300  is formed as follows: a plurality of LED chips  310  are arranged in a zigzag line and mounted on translucent base board  320 ; the sealing material  330  including the wavelength conversion material is applied in zigzag shape along the LED chips  310  arranged in zigzag in an area surrounded by the broken line in  FIG. 8A . The LED chips  310  are located at the inflection points of the zigzag shape. By shaping the sealing material  330  in a shape other than a straight line gives variety to the shape of the filament part. 
         [0116]    In addition, in the embodiment 2, the LED chips  310  are arranged in zigzag on both sides of the base board  320 . The zigzag shaped sealing material  330  is applied on the LED chips  310  on both surfaces. In this case, the sealing materials  330  located on one of the main surfaces (first main surface) and on the other of the main surfaces (second main surface) are preferably formed such that the zigzag shapes cross each other. With this configuration, when viewing the base board  320  from one of the main surfaces, the sealing material  330  on the other main surface can be seen through. With this, the appearance of two entwined filaments can be reproduced. This configuration shall be described with reference to  FIG. 8B .  FIG. 8B  is a diagram illustrating the arrangement of the sealing material  330  according to the embodiment 2. In  FIG. 8B , the arrangement of the sealing material  330  on one of the main surfaces of the base board  320  and the other of the main surfaces of the base board  320  is illustrated in the broken line  333  and the solid line  334 . 
         [0117]    Note that, in the embodiment 2, the LED chips are arranged on both surfaces of one base board. However, it is not limited to this example. For example, two boards on which the LED chips are mounted only on one main surface are prepared and the other main surfaces on which no LED chip is mounted are bonded. With this, the base board on which the LED chips are mounted on both surfaces can be made. In this case, the same effects as the embodiment described above can be achieved. 
         [0118]      FIG. 9  illustrates the circuit configuration of the circuit  380  used for the LED light bulb according to the embodiment 2. As illustrated in  FIG. 9 , in the LED chip row  385  (first series connected group) arranged on one of the main surfaces and the LED chip row  386  (second series connected group) arranged on the other of the main surfaces, the LED chips in the rows of the LED chips are connected in series. Furthermore, the LED chip row  385  and the LED chip row  386  are electrically connected in inverse parallel connection. Furthermore, one of the connecting parts on which one end of the LED chip row  385  and the one end of the LED chip row  386  are connected, and the other connecting part on which the other end of the LED chip row  385  and the other end of the LED chip row  386 , that is, both ends of the inverse parallel connection are connected to the power supply terminals  321  and  322 , and electrically connected to the power supply leads  341  and  342  (in  FIG. 7 ). Note that, the LED chips that are side-by-side belong to different LED chip rows (series connected group). 
         [0119]    In the circuit  380 , the input terminals  381  are electrically connected to the base  390 , and the output terminals  382  are electrically connected to the power supply terminals  321  and  322  in the filament part  300  through the power supply leads  340  ( 341 ,  342 ) in the stem  360 . With the configuration described above, AC power is supplied from the base  390  to the power supply lead  340 , and AC power is supplied to the ends of the inverse parallel connection. With this, in one cycle, one of the LED chip rows (for example, the LED chip row  385 ) is turned on; the other of the LED chip rows (for example, the LED chip row  386 ) is turned off. And it is reversed in the next cycle; thereby the two LED chip rows  385  and  386  keep alternately blinking. Accordingly, in the embodiment 2, the lighting circuit can be configured without using electronic parts for converting the AC power to the DC power such as a diode bridge for rectification. This allows composing the circuit only with the resistor  383  for adjusting current, simplifying the circuit configuration. 
         [0120]    Note that, in the embodiment 2, the power supply leads  340  ( 341 ,  342 ) are attached to the base board  320  in a direction that both of the main surfaces of the base board  320  on which the LED chips  310  are mounted facing the side part of the globe  370 . Note that, the direction of the attachment of the power supply leads  340  ( 341  and  342 ) on the base board  320  may be appropriately determined depending on the design of the LED light bulb. In addition, in the embodiment 2, the filament part  300  is arranged in a direction that the rows of the LED chips  310  composing the filament part  300  crosses the central axis of the globe  370 . The direction may be appropriately determined depending on the design of the LED light bulb. For example, the filament part  300  may be arranged in parallel with or oblique to the central axis of the globe  370 . 
         [0121]    As described above, in the LED light bulb  2  according to the embodiment 2 of the present invention, the light-distribution pattern with a wide light-distribution angle can be achieved, achieving the omnidirectional light-distribution property close to that of the incandescent light bulb, in the same manner as the embodiment 1. 
         [0122]    (Variation of Filament Part) 
         [0123]    Next, a variation of the LED light bulb according to the embodiment 2 of the present invention shall be described with reference to  FIGS. 10 to 13 .  FIGS. 10 to 13  are diagrams for illustrating the variations  1  to  4  of the filament part in the LED light bulb according to the embodiment 2 of the present invention. Note that, for simplifying the description, illustration of the LED chips and the power supply terminals is omitted in these diagrams. Note that, the configuration of the sealing material is the same as described above, and the sealing material includes the wavelength conversion material. 
         [0124]    In the filament part  400  in the variation  1  illustrated in  FIG. 10 , three translucent base boards  420  ( 421 ,  422 , and  423 ) on which the LED chips are mounted compose three side faces of a triangle pole, and the entire triangle pole is covered with the sealing material  430  including the wavelength conversion material, forming a cylindrical light-emitting unit as a whole. As described above, the filament part  400  according to the variation  1  reproduces the shape of the cylindrical filament. 
         [0125]    This configuration is advantageous because the power supply leads (not illustrated) may be inserted and fixed in the inner area  425  of the triangle pole surrounded by the three base boards  421 ,  422 , and  423 . With this, it is possible to actively radiate the heat generated at the LED chip through the power supply leads. 
         [0126]    The filament part  500  in the variation  2  illustrated in  FIG. 11  is composed of three translucent base boards  520  ( 521 ,  522 , and  523 ) on which the LED chips are mounted are arranged such that the cross-section is U-shaped with all corners in straight angles. 
         [0127]    This configuration is advantageous because the LED chip mounted surface of the base board  522  in the middle is arranged facing the top side of the globe. In addition, the LED chip mounted surfaces of the base boards  521  and  523  on both sides are arranged facing the side surface of the globe. With this configuration, the sealing material  530  can be recognized from any direction. With this, the light-emission shape of the filament part  500  is even more close to the light-emission shape of the filament of the incandescent light bulb when emitting light. 
         [0128]    The filament part  600  according to the variation  3  illustrated in  FIG. 12  is composed by arranging the LED chips and the sealing material  630  wound around the translucent polygonal column base board  620 . 
         [0129]    The configuration is advantageous because the shape of the filament of the conventional incandescent light bulb, that is, a spring shape can be reproduced. 
         [0130]    The filament part  700  according to the variation  4  in  FIG. 13  is composed by arranging the LED chips and the sealing material  730  in a ring on the circular translucent base board  720 . 
         [0131]    Note that, the shape of the arrangement of the LED chips and the sealing material  730  is not limited to a circular ring, but may be a shape that cannot be achieved by the filament of the conventional incandescent light bulb such as square, star, characters, graphic, signs, or cartoon characters. 
         [0132]    In addition, the shape of the base board  720  may also have a variety not only square or circle, but also star, characters, graphic, signs, or cartoon characters. 
         [0133]    (Other Variation of Filament Part and Others) 
         [0134]    The light bulb shaped lamp according to the present invention has been described above based on the embodiments and variations. However, the present invention is not limited to the embodiments and others. 
         [0135]    In the embodiments the filament part is configured to emit white light using the LED chips and the sealing material including the wavelength conversion material as an example. However, it is not limited to this example. 
         [0136]    For example, the filament part can be configured with yellow to amber LED chips along with translucent sealing material that does not include the wavelength conversion material. Light bulb with low luminous flux is generally used for purposes that does not require high color rendition. For these purposes, the light from incandescent light bulb can be reproduced using only the light from the LED chip. 
         [0137]    Needless to say, the color of light emitted from the LED chip, whether or not the wavelength conversion material is used, or the type of the wavelength conversion material may also be selected appropriately. 
         [0138]    For example, a configuration in which LED chips of light&#39;s three primary colors, i.e., blue, green, and red are used to obtain white light, a configuration in which LED chips having a wavelength from blue-violet to a near-ultraviolet range, and phosphors of the three primary colors, i.e., blue, green, and red are used to obtain white light, or a configuration in which light in a single color such as blue only, green only, or red only is used is possible as a configuration of the filament part. 
         [0139]    In addition, although LED is used as an example of the light-emitting device in the embodiments, the light-emitting device may be a semiconductor laser, organic electro luminescence (EL), or inorganic EL. 
         [0140]    The LED light bulb according to the embodiments and the variations may be attached to the lighting equipment provided on the ceiling of a room, and can be implemented as a lighting apparatus. The lighting apparatus includes the LED light bulb and the lighting equipment (light-up equipment). The lighting equipment includes an equipment body attached to the ceiling and a lamp cover covering the LED light bulb, and a socket for attaching the base of the LED light bulb is provided in the equipment body. Power is supplied to the LED light bulb through the socket. 
         [0141]    Those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention. 
       INDUSTRIAL APPLICABILITY 
       [0142]    The light bulb shaped lamp according to the present invention reproduces the simulated filament of the incandescent light bulb by the light-emitting device such as the LED chips and the base board. The present invention is particularly effective for a light bulb shaped lamp replacing conventional incandescent light bulbs, and particularly a light bulb shaped lamp replacing the incandescent light bulb for decorative purpose showing the filament. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           1 , 2  LED light bulb 
           100 ,  200 ,  300 ,  400 ,  500 ,  600 ,  700  Filament part 
           110 ,  210 ,  310  LED chip 
           111  Sapphire board 
           112  Nitride semiconductor layer 
           113  Cathode electrode 
           114  Anode electrode 
           115 ,  116  Wire bonding part 
           117  Gold wire 
           118  Chip bonding material 
           120 ,  220 ,  320 ,  420 ,  421 ,  422 ,  423 ,  520 ,  521 ,  522 ,  523 ,  620 ,  720  Base board 
           121 ,  122 ,  321 ,  322  Power supply terminal 
           125 ,  225  First main surface 
           126 ,  226  Second main surface 
           130 ,  230 ,  330 ,  430 ,  530 ,  630 ,  730  Sealing material 
           140 ,  141 ,  142 ,  340 ,  341 ,  342  Power supply lead 
           160 ,  360  Stem 
           170 ,  370  Globe 
           180 ,  380  Circuit 
           181 ,  381  Input terminal 
           182 ,  382  Output terminal 
           183  Diode bridge 
           184  Capacitor 
           185 ,  383  Resistor 
           186 ,  385 ,  386  LED chip row 
           190 ,  390  Base 
           191  Screw part 
           192  Eyelet 
           221 ,  222  Through hole 
           223  Metal line pattern 
           425  Inner area

Technology Category: 5