JP2012142316A - Led bulb - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems that, although a conventional LED bulb mounts LEDs on an outer side face axially perpendicular to an outer side wall along an axial direction of a cylindrical board and it can emit strong light also in a direction perpendicular to the axis of the board by preparing a translucent cover so as to cover the board and it can widen an irradiation range (a light distribution area), manufacturing processes of the LED bulb become complicated and accordingly, manufacturing cost of the LED bulb becomes higher.SOLUTION: The LED bulb includes a plurality of LED light sources 2; a heat radiation section having a light source mounting surface 3 wherein the plurality of LED light sources 2 are arranged in a circumferential state; a reflecting body 6 having a pillar-shaped projection 12 surrounded by the plurality of LED light sources 2 and projected from a light-emitting surface of the LED light sources 2 to a light-emitting direction and a reflecting surface 11 equipped with a light extraction window corresponding to positions and shapes of the LED light sources 2; and a light-transmitting section 5 for covering the plurality of LED light sources 2 and the reflecting body 6 and reflecting at least part of light emitted from the LED light sources 2.

Description

  The present invention relates to an LED bulb having a wide light distribution by using a reflector.

  In recent years, lighting devices using light emitting diodes (hereinafter referred to as LEDs) as light sources have been developed, and LED bulbs using LEDs as light sources have been proposed (for example, Patent Document 1).

  FIG. 12 is a longitudinal sectional view of a conventional LED bulb 101 described in Patent Document 1. In the LED bulb, an LED 105 is mounted on an outer wall 103 along the axial direction of a cylindrical substrate 102 and an outer surface 104 perpendicular to the axial direction, and a translucent cover 106 is provided so as to cover the substrate 102. . With this configuration, particularly strong light can be emitted in a direction perpendicular to the axial direction of the substrate 102 of the LED bulb 101, and the luminous intensity distribution (light distribution) of the LED bulb 101 can be widened. .

JP 2001-243807 A

  However, the LED light bulb 101 described in Patent Document 1 requires a plurality of LEDs 105 to be mounted on both the outer wall 103 and the outer surface 104 of the cylindrical substrate 102, which makes the manufacturing process complicated and makes it difficult to manufacture the LED bulb 101. There was a problem of high costs.

  This invention is made | formed in view of the said problem, and it aims at providing the LED bulb which made light distribution wide by simple structure.

  The LED bulb of the present invention includes a plurality of LED light sources, a heat dissipating part having a light source mounting surface on which the plurality of LED light sources are provided in a circumferential shape, and a substantially center surrounded by the plurality of LED light sources on the light source mounting surface. A reflector attached to the heat dissipating part, having a projecting part projecting in the light emitting direction from the light emitting surface of the LED light source, and a reflective surface provided with a light extraction part corresponding to the position of the LED light source; A light-transmitting part that covers the plurality of LED light sources and the reflector and reflects at least a part of the light from the LED light source, and the projecting part reflects light reflected by the light-transmitting part. It reflects in the side peripheral surface direction of this.

  According to the present invention, light is emitted in a direction different from the light emission direction by reflecting light emitted from a circumferentially mounted light source by a protruding portion protruding in the light emission direction from the light emitting surface of the light source. Therefore, the light distribution of the LED bulb can be widened with a simple configuration including a reflector.

  The LED bulb of the present invention is further characterized in that the protruding portion has a cylindrical shape in which an end face in the light emitting direction is closed with a reflector.

  According to the present invention, when the light emitted from the light source is reflected in the light emission direction, the projection does not block the light in the light output oblique direction, and is disposed in comparison with, for example, a reflector having a conical projection. It becomes possible to spread light.

  The LED bulb of the present invention is further characterized in that the reflector is made of white polycarbonate resin.

  According to the present invention, the reflector made of white polycarbonate resin having a high reflectance can reduce the absorption of light applied to the reflector and reflect the light efficiently.

  According to the present invention, the light distribution of the LED bulb can be widened with a simple configuration.

It is a principal part assembly perspective view of the illuminating device which concerns on Embodiment 1 of this invention. It is a principal part disassembled perspective view of the illuminating device of FIG. It is a principal part expansion perspective view of the reflector used for the illuminating device of FIG. It is a block diagram of the drive circuit part used for the illuminating device of FIG. It is a circuit diagram of the drive circuit part used for the illuminating device of FIG. It is a vertical light distribution characteristic figure of the illuminating device of FIG. It is a principal part expansion perspective view of the reflector used for the illuminating device which concerns on Embodiment 2 of this invention. It is a vertical light distribution characteristic figure of the illuminating device which concerns on Embodiment 2 of this invention. It is a schematic diagram which shows the optical path of an illuminating device. It is a principal part expansion perspective view of the reflector used for the illuminating device which concerns on Embodiment 3 of this invention. It is a schematic assembly perspective view of the illuminating device which concerns on Embodiment 4 of this invention. It is a longitudinal cross-sectional view of the conventional LED bulb.

  Hereinafter, an illumination device according to an embodiment of the present invention will be described with reference to the drawings. Note that an LED bulb using an LED as a light source will be described as an example of the lighting device.

(Embodiment 1)
FIG. 1 is an essential part assembly perspective view of the lighting apparatus according to Embodiment 1 of the present invention. FIG. 2 is an exploded perspective view of a main part of the illumination device of FIG. FIG. 3 is an enlarged perspective view of a main part of a reflector used in the illumination device of FIG. FIG. 4 is a block diagram of a drive circuit unit used in the illumination device of FIG. FIG. 5 is a circuit diagram of a drive circuit unit used in the illumination device of FIG. In addition, since the principal part enlarged perspective view of the reflector of FIG. 3 has shown the state attached to the thermal radiation part in which LED of the reflector was mounted, LED is also shown collectively.

  With reference to FIG. 1 to FIG. 5, the configuration of the LED bulb as the illumination device according to Embodiment 1 will be described.

  The LED bulb 1 includes a plurality of (for example, 10) LEDs 2 as light sources, an LED substrate 10 made of glass epoxy on which the plurality of LEDs are mounted, and a light source having one end surface of the LED substrate 10 on which the plurality of LEDs 2 are mounted. A heat radiating part 4 attached to the attachment surface 3, a diffusion cover 5 as a light transmitting part for diffusing and irradiating light from the plurality of LEDs 2, and a part of the light diffused by the diffusion cover 5 and reflected to the LED side A reflector 6 that reflects light, a drive circuit portion 52 that is housed in a hollow housing portion (not shown) provided inside the heat radiating portion 4 and drives the LED 2, and is fitted into the housing portion. A cylindrical insulating socket 8 that retains electrical insulation between the drive circuit section 52 and the heat radiating section 4, and a base 9 that is screwed into one end of the insulating socket 8 and connected to a commercial power source. Yes.

  The LED 2 is a surface-mounted LED in which a blue LED element is sealed with a sealing resin containing a yellow phosphor, and blue light from the blue LED element and yellow phosphor are excited by light from the blue LED element. Pseudo white light can be emitted by the yellow light emitted.

  The heat radiating part 4 is made of a light metal having high thermal conductivity, such as aluminum, and has a plurality of heat radiating fins on the outer peripheral surface. Moreover, although the LED board which consists of glass epoxy which has electrical insulation is attached to the light source attachment surface 3 of the one end surface of the thermal radiation part 4, an aluminum substrate with high heat conductivity is used as an LED board for a thermal radiation part. It may be attached. In addition, when using an aluminum substrate, in order to maintain the electrical insulation of a LED board and a heat radiating part, attaching to a heat radiating part via an insulating sheet is preferable. Further, although not shown, the light source mounting surface 3 is provided with a wiring insertion hole through which a wiring for connecting the drive circuit section 52 accommodated in the accommodating section of the heat radiating section 4 and the LED 2 is inserted.

  The diffusion cover 5 is a milky white cylindrical cover made of polycarbonate resin, and diffuses light from the LED 2 by mixing diffusion particles in the polycarbonate resin and emits the light to the outside. Further, a part of the light emitted from the LED 2 and diffused by the diffusion cover 5 is reflected to the LED side inside the cylinder without passing through the diffusion cover 5 according to the light transmittance of the diffusion cover 5.

  In addition, the diffusion cover 5 has a diffusion plate (not shown) separate from the diffusion cover 5 attached to the cylindrical inner side of the top surface 14 so that the light transmittance of the top surface 14 is increased around the top surface 14. It is smaller than the light transmittance of the side peripheral surface 15. That is, if the top surface 14 of the diffusion cover 5 is the first portion and the side peripheral surface 15 is the second portion, the light transmittance of the first portion is made smaller than the light transmittance of the second portion, and the diffusion cover 5 is It is composed. If the light absorption in the diffusion cover 5 and the diffusion plate is slight and substantially the same, the smaller the light transmittance, the more light that is reflected without passing through the diffusion cover 5.

  By configuring the diffusion cover 5 as described above, the amount of light emitted from the top surface 14 of the diffusion cover 5 is reduced, and the reduced amount of light is reflected by the inside of the diffusion cover 5 and the reflector 6 to transmit light. There is a high possibility that the light is emitted from the side peripheral surface having a large rate. Therefore, even if the light source is a highly directional LED, light can be emitted from the entire top surface 14 and side peripheral surface 15 of the diffusion cover 5, so that the light distribution of the LED bulb can be widened. .

  In the first embodiment, in order to make the light transmittance of the top surface 14 of the diffusion cover 5 smaller than the light transmittance of the side peripheral surface 15, a diffusion plate is attached to the top surface 14. However, the light transmittance of the top surface 14 may be reduced by making the thickness of the top surface 14 of the diffusion cover 5 thicker than the thickness of the side peripheral surface 15. The surface 15 may be formed of another material, and the top surface 14 may be realized by using a material having a light transmittance smaller than that of the side peripheral surface 15.

  The reflector 6 is made of a white polycarbonate resin having a high reflectance, and has a disk-like reflecting surface 11 that matches the shape of the light source mounting surface 3 of the heat dissipating part 4 and a cylindrical shape provided at substantially the center of the reflecting surface 11. It is comprised from the protrusion part 12 of this.

  The reflective surface 11 has a plurality of light extraction windows 13 corresponding to the position and shape of the LED 2 mounted on the light source mounting surface 3, and the reflector 6 is the same surface as the side on which the LED 2 is mounted. It is attached to the light source attachment surface 3 of the heat radiating part 4 on the side. Further, the reflector 6 is provided so as to protrude in the light emitting direction from the light emitting surface of the LED 2 at a substantially central portion of the plurality of LEDs 2 on which the protruding portions 12 are mounted in a circumferential shape.

  In addition, since the protrusion 6 and the reflective surface 11 are integrally molded in the reflector 6, the protrusion 12 and the reflective surface 11 are collectively attached to the heat radiating portion by attaching the reflective surface 11 to the light source mounting surface 3. 4 can be attached. Therefore, the manufacturing process can be simplified and the manufacturing cost can be reduced.

  Further, the reflector 6 widens the light distribution of the LED bulb by reflecting again the light from the LED 2 and the light reflected by the diffusion cover 5, and this point is described in detail while showing a light distribution diagram. Will be described later.

  Next, the drive circuit unit will be described in detail.

  The drive circuit unit 52 is electrically connected to a commercial power source through a base 9 and wiring disposed from the base 9, and the commercial power source is first connected to the protection circuit unit 53. The protection circuit unit 53 is cut when an overcurrent exceeding the rating flows, and the power fuses (first power fuse 60 and second power fuse 61) that protect the drive circuit unit 52 (particularly the control IC 64) and the LED, A temperature fuse 62 that protects the drive circuit unit 52 (especially the control IC 64) and the LED 2 by cutting when the temperature of the atmosphere around the drive circuit unit 52 exceeds a predetermined temperature, and the drive circuit unit 52 (especially the control IC 64) from overvoltage. And a varistor 59 for protecting the LED 2.

  The output terminal of the protection circuit unit 53 is connected to the filter circuit unit 54. The filter circuit unit 54 includes a capacitor C1, a resistor R2, and a choke coil L1. The filter circuit unit 54 removes noise included in the alternating current supplied from the commercial power source.

  The output terminal of the filter circuit unit 54 is connected to the rectifier circuit unit 55. The rectifier circuit unit 55 is a diode bridge 63 composed of four diodes, and the supplied alternating current is full-wave rectified and output.

  The output terminal of the rectifier circuit unit 55 is connected to the smoothing circuit unit 56. The smoothing circuit unit 56 is a smoothing capacitor, and smoothes the current that has been full-wave rectified by the rectifying circuit unit 55 into a direct current. For example, a large capacity electrolytic capacitor is used as the smoothing capacitor C2.

  The output terminal of the smoothing circuit unit 56 is connected to the constant current control unit 57. The constant current control unit 57 is a control IC, and controls the direct current input from the smoothing circuit unit 56 to supply a constant current to the plurality of LEDs 2 connected in series. The constant current control unit 57 has a built-in transformer as a step-down circuit, and steps down to the magnitude of the drive voltage of the LED 2.

  One output terminal of the constant current control unit 57 is connected to the input terminal of the LED 2, and the other output terminal of the constant current control unit 57 is connected to the dimming circuit unit 58. The dimming circuit unit 58 is a photocoupler and transmits a dimming signal.

  The connection relationship of each electronic circuit component will be described in more detail with reference to the circuit diagram of the drive circuit unit in FIG.

  A varistor 59 is connected in parallel to an AC commercial power supply, a first power fuse 60 is connected to one end of the commercial power supply, and a second power fuse 61 and a thermal fuse 62 are connected to the other end. Next, a resistor R2 and a capacitor connected in series are connected in parallel to the output end of the protection circuit unit 53, and a choke coil L1 is connected to the output end of the first power fuse 60.

  Furthermore, the diode bridge 63 and the smoothing capacitor C2 are connected in parallel in order, and one end of the smoothing capacitor C2 is connected to the control IC 64 which is a constant current control unit 57. One of the output terminals of the control IC 64 is connected to the light source module 2 composed of a plurality of LEDs, and one of the output terminals is connected to the first photocoupler 65 and the second photocoupler 66 that are the dimming circuit unit 58. ing.

  When the dimming control is performed, the dimming signal output from the first photocoupler 66 is input to the control IC 64, and the control IC 64 supplies the dimmed current to the LED according to the dimming signal. It is done by More specifically, a phase control unit (not shown) is provided on the power input side of the drive circuit unit 52, and a power waveform for dimming by performing phase control of AC from a commercial power source by the phase controller unit is shown. Output. Next, the first photocoupler 66 transmits a dimming signal to the control IC 64 in response to the power waveform, and the control IC 64 performs output control (PWM control) according to the dimming signal, The light source module 2 is dimmed.

  With the above configuration, since the alternating current supplied from the commercial power source is converted into a constant current and input to the LED, the LED emits light with a predetermined luminance. Further, by controlling the dimming circuit unit 58, it is possible to switch to a different luminance and emit light. By inputting a signal for switching light control from the outside to the constant current control unit 57, the luminance of the LED can be changed.

  The circuit configuration of the drive circuit unit 52 is an example, and the configuration of each circuit unit is not limited. For example, the drive circuit unit includes a protection circuit including a power fuse, a thermal fuse, and a varistor. However, it is not necessary to include all of the power fuse, the thermal fuse, and the varistor, and only one of them is included. It may be. Moreover, the illuminating device may have only one of a protection circuit part and a light control circuit part.

  Next, the light distribution of the LED bulb will be described.

  FIG. 6 is a vertical light distribution characteristic diagram of the LED bulb of FIG. A line AA ′ in FIG. 6 shows the light distribution of the LED light bulb (hereinafter referred to as LED light bulb A) according to the first embodiment provided with the reflector having the cylindrical protrusion, and is BB ′. The line shows the light distribution of the LED bulb of FIG. 1 (hereinafter referred to as LED bulb B) provided with a reflector having only a disk-like reflecting surface with the protruding portion removed, and the CC ′ line shows the protruding portion. FIG. 2 shows the light distribution of the LED light bulb of FIG. 1 (hereinafter referred to as LED light bulb C) including a reflector having only the disk-shaped reflection surface removed, and further removing the diffusion plate from the diffusion cover.

  The vertical light distribution characteristic diagram is a vertical light distribution curve diagram showing the light intensity distribution (light distribution) in each direction of the LED bulb, and the circumferential direction is a vertical line (light) passing through the light center of the LED as the light source. In the radial direction, the relative intensity is shown with the maximum value being 100%.

  As shown in FIG. 6, the light distribution of the LED bulb A of the first embodiment is wider than any of the light distributions of the LED bulb B and the LED bulb C. In particular, as compared with the LED bulb C, the luminous intensity is large when the angle formed with the optical axis is between approximately 25 ° and approximately 150 °, and the light distribution is wide. On the other hand, when the angle formed with the optical axis is between approximately 0 ° and approximately 20 °, the luminous intensity is small. This is because light emitted in the vertical direction is reflected by the top surface 14 of the diffusion cover 5 having a low light transmittance, and the reflected light is reflected again by the reflector 6, whereby the light transmission of the diffusion cover 5 is performed. This is because light is emitted from the side peripheral surface 15 having a large rate.

  That is, in other words, the light emitted from the LED 2 is obtained by distributing the light emitted from the LED 2 from the top surface 14 to the side peripheral surface 15 by utilizing the reflection at the reflector 6 and the diffusion cover 5. It is possible to spread the light distribution of the LED bulb by effectively utilizing the.

  Moreover, since the light distribution of the LED bulb A is wider than the light distribution of the LED bulb B without the cylindrical projection, it can be seen that the cylindrical projection spreads the light distribution. In addition, although the protrusion part of the reflector of Embodiment 1 is a cylindrical shape, the same effect can be acquired also with the cylindrical reflector which closed the end surface of the light emission direction of a pipe | tube with the reflector.

  As described above, even with an LED bulb that uses a directional LED as a light source with a simple configuration of providing a reflector having a cylindrical protrusion, the light distribution is similar to that of a conventional incandescent bulb. Wide lighting is possible.

(Embodiment 2)
Next, an LED bulb as an illumination device according to Embodiment 2 of the present invention will be described. FIG. 7 is an enlarged perspective view of a main part of a reflector used in the illumination device of Embodiment 2. The illumination device of the second embodiment has the same configuration as the illumination device of the first embodiment except for the reflector. About the same structure, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  The reflector 23 used in the LED bulb of the second embodiment is also made of a white polycarbonate resin having a high reflectance as in the first embodiment, and has a disk shape that matches the shape of the light source mounting surface 3 of the heat radiating section 4. The reflecting surface 11 is composed of a conical protrusion 22 provided substantially at the center of the reflecting surface 11. The reflective surface 11 has a plurality of light extraction windows 13 corresponding to the position and shape of the LED 2 mounted on the light source mounting surface 3, and the reflector 23 is the same surface as the side on which the LED 2 is mounted. It is attached to the light source attachment surface 3 of the heat radiating part 4 on the side. Furthermore, the reflector 23 is provided so as to protrude in the light emitting direction from the light emitting surface of the LED 2 at a substantially central portion of the plurality of LEDs 2 on which the protruding portions 22 are mounted in a circumferential shape.

  In addition, since the protrusion part 22 is shape | molded integrally with the reflective surface 11, the protrusion part 22 and the reflective surface 11 are collectively attached to the thermal radiation part 4 by attaching the reflective surface 11 to the light source attachment surface 3. Therefore, the manufacturing process can be simplified.

  FIG. 8 is a vertical light distribution characteristic diagram of the LED bulb of the second embodiment. 8 indicates the light distribution of the LED light bulb of FIG. 1 (hereinafter referred to as LED light bulb D) provided with a reflector having a cylindrical protrusion, and the EE ′ line indicates the light distribution. 1 shows the light distribution of the LED bulb of FIG. 1 (hereinafter referred to as LED bulb E) provided with a reflector having a conical protrusion according to Embodiment 2, and the FF ′ line is a circle from which the protrusion is removed. The light distribution of the LED light bulb of FIG. 1 (hereinafter referred to as LED light bulb F) provided with a reflector having only a plate-like reflective surface is shown. Note that the LED bulb D to the LED bulb F all have the diffusion plate removed from the diffusion cover.

  As shown in FIG. 8, the light distribution of the LED bulb E according to the second embodiment is wider than the light distribution of the LED bulb F that does not include a reflector having a protruding portion protruding from the light emitting surface of the LED. The light distribution is narrower than the light distribution of the LED bulb D provided with a reflector having a cylindrical protrusion. This makes it possible to widen the light distribution by providing a reflector having a protruding portion that protrudes from the light emitting surface of the LED. However, the shape of the protruding portion is cylindrical rather than conical. It can be seen that the light distribution becomes wider.

  This point will be described with reference to a schematic diagram showing an optical path of light emitted from the LED.

  FIG. 9 shows light emitted from LEDs of an LED bulb (LED bulb D) having a reflector having a cylindrical projection and an LED bulb (LED bulb E) having a reflector having a conical projection. It is a schematic diagram which shows these optical paths. FIG. 9A is a schematic diagram of an LED bulb D provided with a reflector having a cylindrical projection, and FIG. 9B is a schematic diagram of an LED bulb E provided with a reflector having a conical projection. is there.

  As shown in FIG. 9, in any LED bulb, the light emitted from the LED is highly directional, so most of the light reaches the top surface, and part of the light passes through the diffusion cover and is emitted to the outside. Part of the light is diffusely reflected by the diffuser cover. However, even if the directivity of the light source of the LED is strong, some light reaches the reflector directly and is reflected as shown in the figure. At this time, when the protrusion of the reflector has a cylindrical shape (LED bulb D), the reflection surface of the protrusion has the light of the LED light than when the protrusion has a conical shape (LED bulb E). Since it is almost parallel to the axial direction, more light is reflected in the direction of the side surface and emitted from the side surface of the diffusion cover. Therefore, the LED bulb D has a wider light distribution than the LED bulb E.

  6 and 8, the light distribution of the LED bulb A with the diffusion plate attached to the top surface of the diffusion cover is more than the light distribution of the LED bulb D that does not have the diffusion plate on the top surface of the diffusion cover. It is getting wider. Therefore, the light transmittance of the first portion, which is the top surface facing the LED of the diffusion cover, is made smaller than the light transmittance of the second portion, which is the side peripheral surface surrounding the first portion, thereby arranging the LED bulb. Light can be widened.

(Embodiment 3)
Next, an LED bulb as an illumination device according to Embodiment 3 of the present invention will be described.

  FIG. 10 is an enlarged perspective view of a main part of a reflector used in the illumination device of the third embodiment. The illumination device of the third embodiment has the same configuration as that of the first embodiment except for the reflector. About the same structure, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  The reflector 33 used in the LED bulb of the third embodiment is also made of a white polycarbonate resin having a high reflectance as in the first embodiment, and has a disk shape that matches the shape of the light source mounting surface 3 of the heat radiating section 4. The reflecting surface 11 and a hemispherical protrusion 32 provided substantially at the center of the reflecting surface 11 are configured. The reflective surface 11 has a plurality of light extraction windows 13 corresponding to the position and shape of the LED 2 mounted on the light source mounting surface 3, and the reflector 33 is the same surface as the side on which the LED 2 is mounted. It is attached to the light source attachment surface 3 of the heat radiating part 4 on the side. Moreover, the reflector 33 is provided in the substantially center part of several LED2 in which the protrusion part 32 was mounted in the shape of a circle so that it may protrude in the light-projection direction from the light emission surface of LED2.

  Also in the LED bulb of the third embodiment, the reflector 33 has the hemispherical protrusion 32 that protrudes from the light emitting surface of the LED 2, so that the light emitted from the LED 2 and the diffusion cover 5 are, as described above. Since the possibility that the light reflected by the top surface 14 will be emitted from the side peripheral surface 15 increases, the light distribution of the LED bulb can be widened.

(Embodiment 4)
Next, an LED bulb as an illumination device according to Embodiment 4 of the present invention will be described.

  FIG. 11 is a schematic assembly perspective view of the illumination device of the fourth embodiment. The lighting device of the fourth embodiment has the same configuration as that of the lighting device of the first embodiment except for the heat dissipating part. About the same structure, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  In the LED light bulb 41 of the fourth embodiment, the heat radiation part 42 has a cylindrical shape, and has a plurality of very shallow heat radiation grooves 43 (depth of about 1.5 mm) parallel to the axial direction of the cylinder. The heat radiating portion 43 is made of a light metal having high thermal conductivity such as aluminum, and is the same as the heat radiating portion of the first embodiment except for the shape. By making the heat radiating groove 43 shallow, the cleaning performance of the heat radiating groove 43 is enhanced, and it is possible to install not only indoors but also outdoors with much dust such as a poultry house.

  Although not shown in the drawing, the diffusion cover 5 has a plurality of LEDs circumferentially mounted on the light source mounting surface on one end surface of the heat radiating portion 43 as in the first embodiment. A reflector having a protruding portion protruding from the light emitting surface of the LED is provided in the approximate center surrounded by the LED. The shape of the protruding portion is not limited to a cylindrical shape, and may be a conical shape, a hemispherical shape, a polygonal pyramid shape, or the like. By adopting such a configuration, the LED bulb 41 of the fourth embodiment can also widen the light distribution of the LED bulb as shown in the vertical direction light distribution characteristic diagrams of FIGS. 6 and 8. .

  In the above description of the embodiment, the LED bulb has been described as an example of the illumination device of the present invention. However, the present invention is not limited to this, and an illumination device that controls light distribution using a reflector such as a spotlight or a downlight. There may be. The light source is not limited to the LED, but may be another semiconductor light emitting element, EL (Electroluminescence), or the like. Further, the LED of the light source is not limited to a pseudo white LED, and may be an LED having a different color temperature such as a light bulb color or a neutral white color. Furthermore, it is not limited to white, LED of another color may be sufficient.

1, 41 Lighting device 2 LED (light source)
6, 23, 33 Reflector 11 Reflecting surface 12, 22, 32 Protruding portion 14 Top surface (first portion)
15 Side surface (second part)

Claims (3)

A plurality of LED light sources;
A heat dissipating part having a light source mounting surface on which the plurality of LED light sources are provided in a circumferential shape;
Reflection provided with a protruding portion protruding in the light emitting direction from the light emitting surface of the LED light source at a substantially center surrounded by the plurality of LED light sources on the light source mounting surface, and a light extraction portion corresponding to the position of the LED light source And a reflector attached to the heat dissipation part,
A light-transmitting part that covers the plurality of LED light sources and the reflector and reflects at least part of light from the LED light sources;
The LED light bulb according to claim 1, wherein the protruding portion reflects light reflected by the light transmitting portion toward a side surface of the light transmitting portion.   The LED light bulb according to claim 1, wherein the protruding portion has a cylindrical shape in which an end surface in a light emitting direction is closed with a reflector.   The LED light bulb according to claim 1 or 2, wherein the reflector is made of white polycarbonate resin.

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