JP6407654B2 - LED module and lighting device - Google Patents

Description

  Embodiments described herein relate generally to an LED module and a lighting device.

  Recently, an illumination device (white LED illumination device) having a white LED light source that obtains white light by combining a blue LED (light emitting diode) chip and a phosphor as a light source has become widespread. This white LED lighting device has various advantages such as less power consumption than conventional incandescent bulbs, but on the other hand, it has a high blue light emission peak and emits light of a color close to natural light. Have considerably different luminescent properties.

  Incandescent light bulbs emit light with a brightness and shade close to that of natural light and are unknowingly accepted by the world. Therefore, a white LED lighting device is also required to shine like an incandescent bulb (light brightness and hue).

Japanese Patent No. 486098 Japanese Patent Laid-Open No. 10-242513

  Then, embodiment of this invention makes it a subject to provide the LED module and illuminating device which can reproduce the lighting method and hue similar to the filament of an incandescent bulb.

  According to the embodiment, an LED light source that emits visible light, a visible light transmissive axisymmetric transparent member provided so as to cover the LED light source, and an inner portion of the axisymmetric transparent member that is spaced apart from the LED light source And an axially symmetric light scattering member that scatters visible light incident from the LED light source through the axially symmetric transparent member and emits the visible light to the outside of the axially symmetric member. The light scattering member is disposed so that a projection image projected in parallel toward the light emitting surface overlaps at least a part of the light emitting surface, and the emitted light is continuous in a wavelength region of 380 nm to 780 nm. The emission spectrum distribution is shown.

It is a graph which shows spectral luminous efficiency V ((lambda)). It is a side view which shows the LED light bulb as a proof apparatus which concerns on embodiment. FIG. 3 is a perspective sectional view of the LED bulb shown in FIG. 2. The perspective view which shows the LED module of embodiment. The expansion side surface schematic diagram showing the LED module of an embodiment. It is a plane schematic diagram of a multiple combination LED light source. It is a circuit diagram of a multiple combination LED light source. 3 is a graph showing the light emission characteristics of the LED module produced in Example 1. 6 is a graph showing the light emission characteristics of the LED module produced in Example 2. 6 is a graph showing the light emission characteristics of the LED module produced in Example 3. 6 is a graph showing the light emission characteristics of the LED module produced in Example 4. 10 is a graph showing the light emission characteristics of the LED module produced in Example 5. 10 is a graph showing the light emission characteristics of the LED module produced in Example 6. 10 is a graph showing the light emission characteristics of the LED module produced in Example 7. 10 is a graph showing the light emission characteristics of the LED module produced in Example 8. 10 is a graph showing the light emission characteristics of the LED module produced in Example 9. 10 is a graph showing the light emission characteristics of the LED module produced in Example 10. 6 is a graph showing the light emission characteristics of the LED module produced in Comparative Example 1. 10 is a graph showing the light emission characteristics of the LED module produced in Comparative Example 2.

  The LED module of the embodiment includes an LED light source, a visible light transmissive transparent member, and a light scattering member provided inside the transparent member, and emits visible light. The illumination device of the embodiment includes a globe including the LED module of the embodiment, a heat dissipating case connected to the globe and thermally connected to the LED module, and an alternating current included in the heat dissipating case. And a base connected to the heat radiating casing and supplied with electric power from the outside.

  The incandescent bulb uses the radiation of Joule heat of the filament in the glass bulb for light emission, but the spectral distribution of the radiated light is close to black body radiation due to the principle of light emission, and the wavelength distribution is approximately a color temperature of 2500 to 3000K. The shape is close to that of blackbody radiation.

  In the embodiment, the LED light source includes at least one LED chip and a phosphor layer formed to cover the at least one LED chip. Light (primary light) emitted from the LED chip itself is wavelength-converted by the phosphor layer and emitted from the LED light source as secondary light. This secondary light is a continuous spectrum white light containing a light emission component in the entire wavelength region of visible light (a wavelength region of 380 nm to 780 nm), and its emission spectrum shape approximates the emission spectrum of blackbody radiation, It emits light very close to an incandescent bulb.

More specifically, the white light source of the embodiment has the following relational expression (I) in a visible light wavelength region and a wavelength λ of 380 to 780 nm:
−0.15 ≦ [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V ( λmax2))] ≦ + 0.15
It is preferable to satisfy.

  In the relational expression (I), P (λ) is the emission spectrum of the white light source, B (λ) is the emission spectrum of black body radiation showing the same color temperature as the white light source, and V (λ) is It is a spectrum of spectral luminous efficiency, λmax1 is a wavelength at which P (λ) × V (λ) is maximum, and λmax2 is a wavelength at which B (λ) × V (λ) is maximum.

  In the relational expression (I), [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V (λmax2))] represents a difference spectrum between the emission spectrum of the white light source and the emission spectrum of black body radiation having the same color temperature as the white light source. When this difference spectrum (hereinafter referred to as A (λ)) is not less than −0.15 and not more than +0.15, the white LDE light source exhibits an emission spectrum shape approximate to the emission spectrum of black body radiation. become.

  Here, the emission spectrum P (λ) of the white light source can be obtained by total luminous flux measurement using an integrating sphere according to JIS-C-8152. The color temperature (unit: Kelvin (K)) can be calculated from the emission spectrum.

The emission spectrum B (λ) of black body radiation that is the same as the color temperature of the white light source can be obtained from the Planck distribution. The plank distribution is represented by the following formula (X).

  In formula (X), h is the Planck constant, c is the speed of light, λ is the wavelength, e is the base of the natural logarithm, k is the Boltzmann constant, and T is the color temperature. Among these, since h, c, e, and k are constants, if the color temperature T is determined, an emission spectrum corresponding to the wavelength λ can be obtained. Therefore, when the color temperature of the white light emitted from the LED module or the illumination device is determined, the emission spectrum distribution of the black body radiation according to the color temperature is calculated, and at the same time, B (λ) × V (λ) is also obtained. B (λ) × V (λ) indicates the emission spectrum distribution of black body radiation viewed through the human eye.

  Spectral luminous efficiency refers to the sensitivity of the human eye to light. Visibility is defined by the CIE (International Commission on Illumination) as standard spectral relative luminous sensitivity V (λ). Specific luminous efficiency has the same meaning. This spectral luminous efficiency is shown by the spectral distribution given in FIG.

  The human eye has a high sensitivity to yellow, and its sensitivity is equal to zero for ultraviolet rays having a shorter wavelength than purple and infrared rays having a longer wavelength than deep red. For this reason, the spectral luminous efficiency has a peak at a wavelength of about 550 nm, and has a spectral distribution in which the relative emission intensity is nearly zero at a wavelength of 400 nm or less and a wavelength of 700 nm or more.

  In addition, the white light source of the present invention desirably exhibits an emission spectrum shape that is more approximate to the emission spectrum of blackbody radiation, and for that purpose, it is more desirable to satisfy the following relational expression (II).

Relational formula (II):
−0.10 ≦ A (λ) ≦ + 0.10.

  Now, as described above, the white light source of the embodiment converts the wavelength of the primary light emitted from the LED chip by the phosphor and emits it from the LED light source as secondary light.

  Phosphors include materials that exhibit various emission colors and emission spectrum shapes, and by combining several phosphor materials, the emission spectrum of black body radiation can be reproduced. In that case, it is preferable to use an LED chip having an emission peak wavelength in the range of 350 to 420 nm. Some ordinary white LED light sources obtain white light by combining a blue light emitting LED chip with a yellow light emitting or red light emitting phosphor, but it is not preferable to use a white light emitting LED in the embodiment. In general, the emission spectrum of an LED chip has a sharp shape, and when combined with a phosphor showing a relatively broad emission spectrum, a gap occurs in the peak height between the two. For this reason, only the light emitting region of the LED chip protrudes in the wavelength region of white light emission, and it becomes difficult to smoothly reproduce the spectral shape of the black body radiation. On the other hand, ultraviolet light and violet light having a wavelength in the range of 350 to 420 nm have low visibility, so even if they emit sharp light, they cannot be detected by human eyes or are weak even if they can be detected. Since it is light emission, there is little adverse effect on the spectral shape.

  As is clear from the above, the phosphor combined with the LED chip in the embodiment is excited by the primary light from the LED chip whose emission peak wavelength is in the range of 350 to 420 nm, and wavelength-converts this wavelength. Is preferably a phosphor that emits visible light within a range of 420 to 780 nm. In that case, since it is difficult to reproduce the black body radiation spectrum in the entire visible light region with one type of phosphor, usually, four or more different types, and further five or more types of phosphors are used. In that case, it is preferable that the peak wavelengths of the four or more phosphors to be used are shifted from each other by 10 to 100 nm, more preferably 10 to 50 nm. That is, a white light source satisfying the relational expression (I) is obtained by combining four or more, or even five or more types of phosphors from the blue region to the red region and shifting the peak wavelength every 10 to 100 nm. be able to.

  Here, preferred phosphors used in the embodiment are described below. Each of the phosphors described below takes into consideration the emission color, emission intensity, and the like, and exhibits optimum characteristics to satisfy the relational expression (I). In addition, the composition range of each phosphor is limited, but this defines the range in which emission spectral characteristics (peak wavelength, spectrum shape) that can exhibit a desired effect can be obtained in each phosphor. . Therefore, white light having a desired color temperature can be obtained by combining several phosphors having the composition ranges described below. Basically, one type of each phosphor is selected from the following blue phosphor, green phosphor, yellow phosphor, and red phosphor, and combined to obtain the white light emitting phosphor layer of the present invention. It is possible. However, it is not necessary to limit to this basic combination. For example, two types of phosphors are used in combination among red phosphors, or an intermediate blue-green phosphor is additionally mixed to form 5 to 6 types of combinations. It is also possible to do.

<Blue phosphor>
Europium activated alkaline earth chlorophosphate phosphor:
_{(Sr 1-xyxz Ba x Ca} y Eu z) 5 (PO 4) 3 Cl ... chemical formula (A)
Here, 0 ≦ x <0.3, 0 ≦ y <0.1, 0.005 ≦ z <0.15
-Europium-activated alkaline earth magnesium aluminate phosphor:
_{(Ba 1-xyxz Sr x Ca} y Eu z) MgAl 10 O 17 ... chemical formula (B)
Here, x <0.5, y <0.1, 0.05 <z <0.4.

<Blue green phosphor>
Europium, manganese activated alkaline earth magnesium aluminate phosphor:
_{(Ba 1-xyz Sr x Ca} y Eu z) (Mg 1-u Mn u) Al 10 O 17 ... chemical formula (C)
Here, x <0.5, y <0.1, 0.15 <z <0.4, 0.3 <u <0.6.

<Green phosphor>
Europium-activated orthosilicate phosphor:
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4 ... chemical formula (D)
Here, 0.2 ≦ x ≦ 0.6, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02
Europium activated strontium sialon phosphor:
(Sr _1-x Eu _x ) _α Si _β Al _γ O _δ N _ω ... Chemical formula (E)
Here, 0 <x <1, 0 <α ≦ 3, 12 ≦ β ≦ 14, 2 ≦ γ ≦ 3.5, 1 ≦ δ ≦ 3, 20 ≦ ω ≦ 22.

<Yellow phosphor>
Europium-activated orthosilicate phosphor:
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4 ... chemical formula (F)
Here, 0 ≦ x ≦ 0.3, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02
・ Cerium-activated strontium sialon phosphor:
_{(M 1-x Ce x)} 2y Al z Si 10-z O u N w ... chemical formula (G)
Here, 0 <x ≦ 1, 0.8 ≦ y ≦ 1.1, 2 ≦ z ≦ 3.5, u ≦ 1, 1.8 ≦ z−u, 13 ≦ u + w ≦ 15, and the element M is Sr Yes, a part of Sr may be substituted with at least one selected from Ba, Ca, and Mg.

<Red phosphor>
Europium activated strontium sialon phosphor:
(Sr _1-x Eu _x ) _α Si _β Al _γ O _δ N _ω ... Chemical formula (H)
Here, 0 <x <1, 0 <α ≦ 3, 5 ≦ β ≦ 9, 1 ≦ γ ≦ 5, 0.5 ≦ δ ≦ 2, 5 ≦ ω ≦ 15
Europium activated calcium strontium oxynitride phosphor:
(Ca _1-xy Sr _x Eu _y ) SiAlN ₃ Chemical formula (I)
Here, 0 ≦ x <0.4, 0 <y <0.5
Manganese activated magnesium fluorogermanate phosphor:
αMgO · βMgF ₂ · (Ge _1−x Mn _x ) O ₂ Chemical formula (J)
Here, 3.0 ≦ α ≦ 4.0, 0.4 ≦ β ≦ 0.6, 0.001 ≦ x ≦ 0.5.

  The phosphor is a powder crystal particle, and the average particle size is preferably about 5 to 40 μm. When the average particle size is less than 5 μm, the crystal particles are not sufficiently grown, so that the emission intensity of the phosphor tends to be low. On the other hand, if the crystal particles are larger than 40 μm, there is no problem with the brightness of the emission color, but it becomes difficult to uniformly mix the phosphors, and uniform emission characteristics can be obtained when a mixture is formed. Disappear.

  The phosphor powder having such a particle size is mixed with a transparent resin material and covers the LED chip in the form of a phosphor layer. By covering the periphery of the LED chip with a phosphor layer, the primary light emitted from the LED chip is converted into secondary light (white light) by the phosphor layer and emitted outside the LED light source. The phosphor layer may be applied immediately above the LED chip, or a transparent resin layer may be formed around the LED chip and formed outside thereof. Which structure is adopted has advantages and disadvantages and can be used depending on the purpose, but it is important to cover the periphery of the LED chip with a phosphor layer without any gap. Since the phosphor layer completely covers the periphery of the LED chip, the primary light from the LED chip can be prevented from leaking directly to the outside of the light emitting device, so that a bright light emitting device with less energy loss can be obtained, and the LED light When UV light is ultraviolet light, ultraviolet light harmful to the human body can be prevented from leaking outside the light emitting device.

  The resin material used in combination with the phosphor is not particularly limited as long as it is a transparent (visible light transmissive) material. For example, an epoxy resin or a silicone resin can be used. However, when an ultraviolet light emitting LED chip is used as the LED chip, it is desirable to use a silicone resin or the like having good deterioration resistance against ultraviolet rays.

  The LED module or lighting device (collectively referred to as a device) using the white light source according to the embodiment may emit white light having a specific color temperature, or may be a device that emits white light having an arbitrary color temperature. May be. Like the latter, a device capable of adjusting to various white lights can be embodied by a white light source system in which white LED light sources having at least two kinds of color temperatures are combined. For example, by mixing white light with a color temperature of 2600K and an LED light source that emits white light with 3600K at an arbitrary intensity ratio, a toning system with 2600K as the lower limit and 3600K as the upper limit can be obtained. At this time, the emission spectrum of both white LED light sources satisfies the relational expression (I) and approximates the spectrum of black body radiation at the same color temperature, so that white light from both white LED light sources is mixed. White light having an intermediate color temperature also satisfies the relational expression (I).

  In such a white light source system, the color temperature of the white light from the LED light source to be mixed with the emitted white light may be any number as long as it is two or more types. In particular, when the difference in color temperature between the two types of light sources is large, the emission spectrum of black body radiation can be reproduced more faithfully by using three or more types of light sources. However, in order to adjust three or more types of white light to obtain white light of a specific color, the electronic circuit for controlling the light emission intensity of the LED light source becomes complicated, so the types of light sources are increased more than necessary. This is not preferable due to restrictions on the design of the light emitting device.

  In the LED module of the embodiment, the visible light transmissive transparent member is axially symmetric and is provided so as to cover the LED light source. It guides visible light emitted from the LED light source. The visible light transmissive transparent member usually has a cylindrical shape. The transparent member can be formed of either an inorganic material or an organic material as long as it transmits visible light. Examples of the inorganic material include glass and transparent ceramics. Examples of the organic material include transparent resins selected from acrylic resins, silicone resins, epoxy resins, polycarbonates, polyethylene terephthalate (PET) resins, polymethyl methacrylate (PMMA) resins, and the like.

  The axially symmetric light scattering member is disposed inside the transparent member, and scatters the white light incident through the transparent member from the LED light source and radiates it to the outside of the transparent member. That is, the transparent member is solid on the proximal end side but hollow on the distal end side, and the axially symmetric light scattering member can be a thin coating film applied to the inner surface of the hollow portion of the transparent member. This coating film contains light scattering fine particles dispersed in a transparent resin. Examples of the fine particles include white pigments such as titania.

  Needless to say, the light scattering member is disposed so that a projection image projected in parallel toward the light emitting surface of the LED light source overlaps at least a part of the light emitting surface. When two or more types of LED light sources that emit white light having different color temperatures are used, a light scattering member is arranged so that the projected image overlaps at least a part of each light exit surface.

  The transparent member is preferably formed so that a portion surrounding the light scattering member has a light collecting function, that is, a lens is formed. For this purpose, the transparent member is formed so that the outer diameter is gradually reduced from the proximal end side toward the distal end side in the portion forming the hollow portion. On the contrary, the hollow portion gradually increases the inner diameter from the proximal end side toward the distal end side. Thus, the thickness of the transparent member decreases from the base end side toward the front end side in the portion surrounding the light scattering member, and the thickness changing portion exhibits a lens function (condensing function), that is, constitutes a lens. To do. Thus, the emitted light (visible light) from the LED light source is guided by the transparent member, and the light reaching the light scattering member is repeatedly reflected in the light scattering member, and the entire surface of the scattering member appears to emit light. The light directed upward from the light scattering member is emitted to the outside as it is, but the light directed toward the side surface and the lower surface is collected by the lens, and the light is directed toward the virtual light source (for example, the bottom surface of the hollow portion). As a result of the concentration, it appears as if light is generated from the virtual light source.

  In addition, the emission spectrum of the emitted light from the LED light source according to the embodiment includes the emission spectrum of the emitted light from the LED module including the LED light source, and the emission of the emitted light from the LED illumination device incorporating the LED module. Same as spectrum.

  2 and 3 show a lighting device 1 according to one embodiment.

  The lighting device 1 includes a globe 2 made of spherical glass and an LED module 10 incorporated in the globe 2. The opening of the globe 2 is sealed with a base 3. The lighting device 1 is configured such that the overall shape and size are similar to those of a conventional incandescent bulb, and can be called an LED bulb.

  The LED module 10 includes an LED light source 13 having a light emitting surface 18. The LED light source 13 is mounted on the substrate 11 using a chip-on-board (COB) technique, and is supported along with the substrate 11 by a cylindrical heat sink 4 having a hollow portion 4c.

  The heat sink 4 constituting the heat radiating housing is made of a metal material having excellent thermal conductivity such as aluminum. The base end portion 4b of the heat sink 4 forms an annular protrusion, and is fixed to the base 3 by caulking the base 3 to the annular protrusion.

  On the other hand, the front end portion 4a of the heat sink 4 supports the axially symmetric transparent member 14 via the perforated cap-shaped lens pressing member 6. That is, the heat sink front end portion 4 a forms a reduced diameter portion that is slightly smaller in diameter than the heat sink main body, and the LED light source 13 is fastened with a plurality of screws 5 to the upper end of the reduced diameter portion. The lens pressing member 6 is put on the outer periphery of the reduced diameter portion of the heat sink. The axially symmetric transparent member 14 is inserted into the opening of the lens pressing member 6 and joined to the light emitting surface 18 of the LED light source 13. The support structure for supporting the transparent member 14 by the lens pressing member 6 is reinforced.

  A lighting circuit 42 is provided in the hollow portion 4 c of the heat sink 4. The lighting circuit 42 is connected to both electrodes of the base 3 and the light emitting circuits of the LED light sources 13 on the substrate 11 by internal wiring. The lighting circuit 42 has an AC / DC conversion function for converting alternating current into direct current and a lighting function for supplying power to the light emitting circuit to cause the LED light source 13 to emit light.

As best shown in FIGS. 3 and 4, the LED module 10 is a combination of an LED light source 13, an axially symmetric transparent member 14, and an axially symmetric light scattering member 15. As described above, the LED light source 13 is basically composed of at least one LED chip (not shown) and the phosphor layer 12 covering the LED chip. In the illustrated example, the LED chip is incorporated in a substrate 11 which is a chip on board (COB) in which an LED light emitting circuit is formed on an alumina substrate, for example. In one embodiment, the thickness t ₁ (average) of the phosphor layer 12 is 400 to 2000 μm.

  The axially symmetric light transparent member 14 is attached to the substrate 11 so as to cover the entire light emitting surface 18 of the LED light source. In this embodiment, the axially symmetric light transparent member 14 has a cylindrical shape as a whole, and is substantially axially symmetric with respect to the light distribution symmetry axis ax. Similarly, the axially symmetric light scattering member 15 is also substantially axially symmetric with respect to the light distribution symmetry axis ax. The axially symmetric transparent member 14 is solid on the proximal end side and hollow on the distal end side. A coating film including the light scattering particles 17 is formed on the inner surface of the hollow portion 14 h of the transparent member, thereby constituting the axially symmetric light scattering member 15.

  The axially symmetric transparent member 14 has an outer diameter that gradually decreases from the proximal end side toward the distal end side along the Z axis. That is, in the axially symmetric transparent member 14, the first intermediate portion 14b having a truncated cone shape is smaller in outer diameter than the cylindrical base end portion 14a, and the second intermediate portion 14c is further smaller than the first intermediate portion 14b. The outer diameter is small, and the outer diameter of the distal end portion 14d is smaller than that of the second intermediate portion 14c.

  On the contrary, the hollow portion 14h of the transparent member gradually increases in diameter from the proximal end side to the distal end side of the transparent member 14, and therefore the inner diameter of the light scattering member 15 increases in the same manner. That is, in the axially symmetric transparent member 14, the inner diameter of the first intermediate portion 14m is larger than the bottom surface 14n on the base end side, the inner diameter of the second intermediate portion 14l is larger than that of the first intermediate portion 14m, and the second The third intermediate portion 14k has a larger inner diameter than the intermediate portion 141, and the tip portion 14j has a larger inner diameter than the third intermediate portion 14k. Note that the bottom surface 14n of the hollow portion forms a flat surface, and thus the bottom surface 15e of the light scattering member 15 also forms a flat surface.

  The taper angles of the parts 14a, 14b, 14c, 14d, 14j, 14k, 14l, 14m, and 14n can be determined using the optical characteristics and analysis method of the entire LED module. Specifically, the thickness of the transparent member 14 that surrounds the light scattering member 15 gradually decreases from the proximal end side toward the distal end side. Such a thickness changing portion 16 has a lens function (condensing function). As described above, the light is guided by the transparent member 14, and the light reaching the light scattering member 15 is repeatedly reflected in the light scattering member 15 so that the entire surface of the light scattering member 15 appears to emit light. The light traveling from the light scattering member 15 toward the distal end side is emitted to the outside as it is, but the light traveling toward the side surface 14s or the proximal end side is condensed by the lens-shaped thickness changing portion 16 and is a virtual light source (for example, As a result of the light concentration toward the bottom surface 14n) of the hollow portion, it appears as if light is generated from the virtual light source.

  In the present embodiment, the light distribution from the LED chip has a light distribution symmetry axis ax, and is a distribution that is close to symmetry with respect to the light distribution symmetry axis ax. Examples of the light distribution include Lambertian, but are not limited thereto. The light distribution symmetry axis ax can pass, for example, near the center in the light emitting surface of the LED chip, but is not limited to this, and passes through any point in the same plane as the light emitting surface 18 of the LED light source. Also good.

The refractive index n of this transparent member and the total reflection angle θc have the relationship of the following formula (A).

  The axially symmetric light scattering member 15 is disposed inside the axially symmetric transparent member 14 and contains light scattering particles that scatter white light from the LED light source 13. The average thickness of the light scattering member 14 is preferably in the range of 50 to 100 μm.

In general, the absorption coefficient μ (1 / mm) of the light scattering member is obtained when a parallel light beam collimated in a direction orthogonal to the flat plate is irradiated to a flat light scattering member having a thickness h (mm). It can be defined using the amount of transmission. When the incident intensity of parallel rays is I ₀ and the transmission intensity is I _T , the absorption coefficient μ is given by the following equation (B).

In order to clarify the closest distance L ₂ between the light scattering member 15 and the LED light source 13, the transparent member 14 is shown not to contact the substrate 11 for the sake of convenience in FIG. The member 14 is in contact with the substrate 11.

  The symmetry axis of the axially symmetric transparent member 14 substantially coincides with the light distribution symmetry axis ax of the LED light source 13, and the symmetry axis of the axially symmetric light scattering member 15 also substantially coincides with the light distribution symmetry axis ax. Yes. In addition, if it is in the range of the product dispersion | variation in the light distribution symmetry axis ax of an LED light source, it can be considered that a symmetry axis substantially corresponds.

It is preferable that the closest distance L ₂ and the area C of the light emitting surface 18 satisfy the relationship of the following formula (1).

Further, it is preferable that the length L ₁ of the light scattering member and the absorption coefficient μ (1 / mm) of the light scattering member satisfy the relationship of the following formula (2).

Furthermore, it is preferable that the diameter d ₁ of the bottom surface 15e of the light scattering member, the closest distance L _2, and the refractive index n of the transparent member satisfy the relationship of the following expression (3).

When the length L ₁ and the absorption coefficient μ satisfy the relationship of the above expression (2), the light from the LED light source does not leak out from the LED bulb 1 without passing through the light scattering member 15.

  Moreover, the following effect is acquired by the relationship of said (3). The light from the LED light source 13 is totally reflected by the side surface 14s of the transparent member except for part of the light scattered by the bottom surface 15e of the light scattering member, and is scattered by the respective portions 15a to 15d of the light scattering member. Thus, since light is repeatedly reflected and scattered and then released to the outside, the entire surface of the light scattering member 15 appears to emit light.

  The cross section orthogonal to the symmetry axis of the light scattering member 15 is included in the cross section of the transparent member 14 in the plane including the cross section. That is, the periphery of the light scattering member 15 is reliably covered with the transparent member 14 on a plane orthogonal to the symmetry axis. Furthermore, the surface obtained by projecting the transparent member 14 in parallel to the light emitting surface 18 of the light source covers the entire light emitting surface 18. In other words, the cross section of the maximum diameter of the transparent member 14 is larger than the light emitting surface 18 of the light source.

Further, the diameter d ₀ of the solid part of the axisymmetric transparent member, the diameter d ₁ of the bottom surface of the axisymmetric light scattering member, the length L ₁ of the axisymmetric light scattering member, the light emitting surface of the LED light source, and the light scattering It is preferable that the closest distance to the member and L ₂ satisfy the following formula (4).

  By satisfying the above conditions, a compact white LED lighting device can be obtained in addition to low loss and low heat generation.

  By the way, it was described above that a white LED light source having at least two kinds of color temperatures can be combined. An example of the combination will be described with reference to FIG. 6 taking a combination of white LED light sources having three color temperatures as an example.

  The LED module 10 shown in FIG. 6 includes three white light sources 13a, 13b, and 13c as light sources. These three white light sources 13a, 13b, and 13c are configured to emit white light having different emission spectra, that is, white light having different color temperatures. Among these, the 1st light source 13a is arrange | positioned in the center area of the light emission surface 18 in the figure, and has the LED chip group 21 so that white light of the highest color temperature (1st color temperature) may be light-emitted. The light emitting circuit and the phosphor layer 12a are combined. Further, the second light source 13b is disposed in the right area of the light emitting surface 18 in FIG. 6 and has a light emitting circuit having an LED chip group 22 so as to emit white light having an intermediate color temperature (second color temperature). And the phosphor layer 12b are combined. Further, the third light source 13c is disposed in the left area of the light emitting surface 18 in FIG. 6 and has a light emitting circuit having the LED chip group 23 so as to emit white light having the lowest color temperature (third color temperature). And the phosphor layer 12c are combined.

  As shown in FIG. 6, these three phosphor layers 12a, 12b and 12c are surrounded by an annular partition 20a and two linear partitions 20b and 20c, and are partitioned from other phosphor layers. Yes. The partition walls 20a, 20b, and 20c shield light provided between the adjacent phosphor layers 12a, 12b, and 12c in order to reduce absorption of primary light between the three LED light source partition walls 13a, 13b, and 13c. It is a thing. Partitions 20a, 20b, and 20c are provided between adjacent phosphor layers 12a, 12b, and 12c, and the phosphor layers 12a, 12b, and 12c are separated from each other by the partitions 20a, 20b, and 20c. The partition walls 20a, 20b, and 20c preferably include high-reflectance inorganic fine particles that can reflect light having a wavelength of 450 to 780 nm up to 98%.

  Here, it goes without saying that the light scattering member is arranged so that the projection image projected in parallel toward the light emitting surface of the phosphor layer overlaps at least a part of each light emitting surface.

  Next, the light emitting circuit of the LED light source according to the present embodiment shown in FIG. 6 will be described with reference to FIG.

  The three light sources 13a, 13b, and 13c are provided with LED chip groups 21, 22, and 23 each including a plurality of LED chips 24, 25, and 26, respectively.

  The light emitting circuit of the first light source 13a is formed by connecting four LED chips 24 in series in the forward direction to form a series connection circuit, and connecting the four series connection circuits in parallel. 21. The LED chip group 21 of the first light source includes 16 LED chips 24 in total.

  The light-emitting circuit of the second light source 13b is formed by connecting three LED chips 25 in series in the forward direction to form a series connection circuit, and connecting the two series connection circuits in parallel. 22. The LED chip group 22 of the second light source includes a total of six LED chips 25. Furthermore, a variable resistor R1 is inserted on the negative electrode side of the light emitting circuit of the second light source 13b. The resistor R1 is connected to the LED chip group 22 in series.

  The light emitting circuit of the third light source 13c is formed by connecting two LED chips 26 in series in the forward direction to form a series connection circuit, and connecting the two series connection circuits in parallel. 23. The LED chip group 23 of the third light source includes four LED chips 26 in total. Further, a variable resistor R2 is inserted on the negative electrode side of the light emitting circuit of the third light source 13c. The resistor R2 is connected to the LED chip group 23 in series.

  Further, even when the series number of the first to third LED chip groups 21, 22, 23 is changed, the position of the intersection of both current-voltage characteristic lines is adjusted by changing the values of the insertion resistors R1, R2. Therefore, it is possible to bring the light emission characteristic line of the white LED lighting device closer to the light emission characteristic line of the incandescent bulb.

  Further, a power supply circuit for supplying power to the light emitting circuits of the three light sources 13a, 13b, and 13c will be described with reference to FIG.

  The light emission circuits of the first to third light sources 13a, 13b, and 13c are collectively connected to the common electrode 27d on the positive electrode side. The positive-side common electrode 27 d is connected to the positive terminal 42 a of the lighting circuit 42.

  On the other hand, in the light emitting circuit of the first light source 13a, the negative electrode side is connected to the individual electrode 27a. The light emitting circuit of the second light source 13b is connected to the individual electrode 27b on the negative electrode side. The light emitting circuit of the third light source 13c is connected to the individual electrode 27c on the negative electrode side. These negative electrodes 27a, 27b, and 27c are connected to the negative terminal 42b of the lighting circuit 42, respectively.

  When the bulb-type lighting device 1 is attached to a commercial AC power source socket serving as the external power source 40, a current flows from the external power source 40 (commercial AC power source) to the lighting circuit 42 in the lighting device, and the lighting circuit 42 is activated. Electric power is supplied to the light emitting circuits of the three light sources 13a, 13b, and 13c, and the LED chip groups 21, 22, and 23 of each light source emit light.

  White light emitted from each of the three light sources 13a, 13b, and 13c has different emission spectra (that is, different color temperatures). These three kinds of white light having different color temperatures pass through the transparent member 14 to the light scattering member 15, where they are mixed by being scattered and emitted to the outside as light close to an incandescent light bulb.

  Examples will be described below.

Example 1
In this example, an LED module having the structure shown in FIGS. In this module, the transparent member 14 having the hollow portion 14h was formed of a transparent acrylic resin (refractive index of about 1.5). And the diameter of the uppermost surface of the transparent member 14 is 6.2 mm, the diameter of the solid part of the transparent member is 10.2 mm, the height L _{0 of the} entire transparent member is 25.4 mm, and the light scattering member The closest distance L ₂ between the LED 15 and the LED light source 13 was 14.8 mm.

  A light-scattering member (light scattering member) having a thickness of μm is applied to the inner surface of the hollow portion 14h of the transparent member 14 by applying a paint containing a titania pigment in a transparent nitrocellulose binder (Purace A7161). Layer) 15 was formed.

  As the LED chip, a purple LED chip having an emission peak wavelength of 410 nm was used.

  As phosphors, the following four types of phosphors (powder) were mixed in the following amounts to obtain mixed phosphor powders.

Blue phosphor: (Sr _0.72 Ba _0.2 Ca _0.01 Eu 0.07) ₅ (PO ₄ ) ₃ Cl 74 parts by weight Green phosphor: (Sr _0.24 Ba _0.55 Mg _0.1 Eu _0.1 Mn _0.01 ) ₂ SiO ₄ 4 parts by weight Yellow phosphor : (Sr _0.769 Ba _0.15 Mg _0.03 Eu _0.05 Mn _0.001 ) ₂ SiO ₄ 7 parts by weight Red phosphor: (Sr _0.9 Eu _0.1 ) ₂ Si ₈ Al ₃ ON ₁₃ 15 parts by weight The obtained mixed phosphor powder 65 parts by weight Then, 35 parts by weight of a transparent silicone resin was mixed well to obtain a resin slurry, which was applied onto the LED chip and dried to form a disk-shaped phosphor layer having a thickness of 550 μm and a diameter of 9.8 mm.

  Thus, an LED module was produced. A white light emitting LED bulb shown in FIGS. 1 and 2 was manufactured by incorporating this LED module. This LED bulb was driven at a driving voltage of 48 V to emit white light. In addition, it was calculated that the produced LED module satisfy | fills all the relationship of Formula (1)-(4).

  White light emitted to the outside from the obtained LED bulb showed a color temperature of 2032K.

The obtained emission spectrum is shown in FIG. In the figure, curve a shows the emission spectrum of the white light source of the LED module produced in this example, while curve b shows the emission spectrum of black body radiation having the same color temperature. From the comparison in FIG. 8A, it can be seen that both curves in the visible light region are close to each other. Moreover, the difference spectrum with respect to the emission spectrum of black body radiation in each wavelength of the LED light source produced in the present Example is shown in FIG. The emission spectrum in this example is
−0.1 ≦ A (λ) ≦ + 0.1
It can be seen that the above-mentioned relationship is satisfied and desirable characteristics as a light source are exhibited.

Examples 2-10
An LED module and an LED bulb were produced in the same manner as in Example 1 except that the phosphors shown in Table 1-1 to Table 1-4 were used.

The color temperatures of the emitted light from the obtained white LED module are shown in Table 1-1 to Table 1-4. In addition, the result about Example 1 is written together in Table 1-1.

  The emission spectrum and the difference spectrum A (λ) of the LED light sources produced in Examples 2 to 10 are shown in FIGS. In these figures, (A) shows the emission spectrum of the LED light source, and (B) shows the difference spectrum A (λ). In each of FIGS. 9 to 17A, curve a represents the emission spectrum of the white light source emitted from the phosphor layer, and curve b represents the emission spectrum of black body radiation having the same color temperature.

  As can be seen from the difference spectra (FIG. 9B) of FIGS. 9 to 17, the emission spectra of the LED light sources produced in Examples 2 to 10 all satisfied the relationship of the relational expression (II). .

Example 11
In this example, an LED module having three types of white LED light sources shown in FIG. 6 was produced, and this was incorporated into a globe to obtain an LED bulb.

  Titania as a white pigment was mixed and stirred in a silicone resin solution at a predetermined ratio, and the obtained slurry was applied linearly to a predetermined area of the LED circuit board by a coating device to form a partition wall. The formed partition walls had an average height of 0.5 mm and an average width of 1.2 mm.

  The phosphor mixture slurry of Example 3 was applied to the first light emitting area of the substrate and dried to form a phosphor layer 12a having a thickness of 480 μm.

  Moreover, the phosphor mixture slurry of Example 2 was applied to the second light emitting area of the substrate and dried to form a phosphor layer 12b having a thickness of 720 μm.

  Next, the phosphor mixture slurry of Example 1 was applied to the third light emitting area of the substrate and dried to form a phosphor layer 12c having a thickness of 630 μm.

Each size in FIG. 6 is shown below.
Width W2: 9.8mm
Width W3: 4.7mm
Width W4: 2.55mm
Other configurations were the same as those in Example 1.

  An LED chip was incorporated in the light emitting circuit shown in FIG. 7, and a COB driving voltage of 3.1 V was applied when a current of 300 mA was applied thereto, and primary light was emitted from each LED chip at an emission wavelength of 400 to 410 nm. As a result, the entire light bulb was equally bright and visible with no color unevenness.

Comparative Example 1
As Comparative Example 1, the light emission characteristics of a commercially available fluorescent lamp and a popular white LED are shown.

The fluorescent lamp is a commercially available product, and an illumination product that emits daylight white light was used as a comparative example. In a fluorescent lamp, ultraviolet light is emitted from mercury gas filled in a glass tube, and the phosphor absorbs the ultraviolet light to emit white light. It is designed to show white light emission by combining several types of phosphors, and has a configuration similar to the light emitting device of the embodiment in that phosphor light emission is used. However, the emission spectrum of white light emitted from a fluorescent lamp is greatly different from that of the present invention as shown by a curve a in FIG. The emission spectrum of the fluorescent lamp has sharp emission peaks in the blue, green, and red wavelength ranges, and the emission intensity between the peaks is low, so that the emission spectrum shape as a whole is extremely uneven. On the other hand, the spectral shape of the black body radiation indicated by the curve b in FIG. 18A shows a gentle curve, and it can be seen that there is a large difference between the two. When the difference spectrum A (λ) between the two is calculated, it is as shown in FIG.
−1.0 ≦ A (λ) ≦ + 0.1
Was in a relationship. Therefore, while the white LED lighting devices of Examples 1 to 11 showed the same emission color as that of the incandescent bulb, the fluorescent light of Comparative Example 1 was similar in appearance to the emission color of the incandescent bulb. However, it showed white light with characteristics that are substantially far from each other. That is, the illumination using the illumination devices of Examples 1 to 11 shows a natural object color as in the case where the illumination target is illuminated by sunlight, whereas the illumination of Comparative Example 1 does not The effect was poor.

Comparative Example 2
As Comparative Example 2, the light emission characteristics of a popular white LED product are shown. The popular white LED has a mechanism of emitting white light by combining a blue light emitting LED and a yellow light emitting phosphor. In other words, blue light is emitted from the LED, and a part of the emitted blue light is absorbed by the phosphor and converted into yellow light, and a part of the blue light of the LED light is combined with the yellow light from the phosphor. It is a mechanism that emits white light. Recently, in addition to yellow phosphors, red phosphors and orange phosphors have been added to increase the number of products that display white light. In any case, most of the currently available white LED products are blue LEDs. And a white light emitting device combining about 1 to 3 types of phosphors. The emission spectrum of such a white light emitting device has a strong blue emission spectrum by the LED and a gentle yellow emission spectrum by the phosphor as shown by the curve a in FIG. An emission spectrum is shown. Naturally, it is very different from the emission spectrum of blackbody radiation (curve b), and the difference spectrum between them showed the following relationship:
−0.3 ≦ A (λ) ≦ + 0.1
Therefore, while the lighting devices of Examples 1 to 11 showed the same emission color as incandescent bulbs, the popular white LED of Comparative Example 2 has an apparent emission color compared to the emission color of incandescent bulbs. Although it was similar, it showed white light with characteristics that were substantially far away. That is, the illumination using the illumination devices of Examples 1 to 11 shows a natural object color as in the case where the illumination target is illuminated by sunlight, whereas the illumination of Comparative Example 2 does not The effect was poor.

前記第２の対称軸に沿った前記軸対称光散乱部材の長さＬ ₁ と、前記軸対称光散乱部材の吸収係数μ（１／ｍｍ）とは下記式（２）の関係を満たし、

前記軸対称光散乱部材の底面の直径ｄ ₁ と、前記最近接距離Ｌ ₂ と、前記軸対称透明部材の屈折率ｎとは、下記式（３）の関係を満たし、

前記第２の対称軸に直交する前記軸対称光散乱部材の断面は、この断面における前記軸対称透明部材の断面に含まれ、
前記第２の対称軸に沿って、前記軸対称透明部材を前記ＬＥＤ光源の発光面に向けて投影した投影像は、前記ＬＥＤ光源の発光面に重なることを特徴とする［１］乃至［１３］いずれかのＬＥＤモジュール。
［１５］前記軸対称透明部材は円柱状であることを特徴とする［１］乃至［１４］いずれかのＬＥＤモジュール。
［１６］前記軸対称透明部材の直径ｄ ₀ と、前記軸対称光散乱部材の底面の直径ｄ1と、前記第２の対称軸に沿った前記軸対称光散乱部材の長さＬ ₁ と、前記ＬＥＤ光源の発光面と前記光散乱部材との最近接距離とＬ2が、下記式（４）の関係を満たすことを特徴とする［１５］の白色ＬＥＤモジュール。

［１７］［１］乃至［１６］いずれかのＬＥＤモジュールを内包するグローブに接続されるとともに前記ＬＥＤモジュールと熱的に接続される放熱筐体と、前記放熱筐体に内包され交流を直流に変換する電源回路と、前記放熱筐体に接続され、外部からの電力が供給される口金を更に備えた照明装置。 Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.
Hereinafter, the invention described in the scope of claims of the present application will be appended.
[1] A visible light LED light source having a light emitting surface for emitting visible light as emitted light, a visible light transmissive axisymmetric transparent member provided so as to cover the LED light source, and the transparent light source spaced from the LED light source An axially symmetric light scattering member that is disposed inside the member and scatters visible light incident from the LED light source through the transparent member and exits the axially symmetric transparent member; and The projection image projected in parallel toward the light exit surface is disposed so as to overlap at least part of the light exit surface, and the exit light exhibits a continuous emission spectrum distribution in a wavelength region of 380 nm to 780 nm. LED module characterized by the above.
[2] The LED module according to [1], wherein the transparent member forms a condensing lens at a portion surrounding the light scattering member.
[3] The axisymmetric transparent member includes a side surface that substantially totally reflects the emitted light emitted from the LED light source, and a thickness change portion in which the thickness gradually decreases from the base end side toward the tip end side. Have
The thickness change portion is formed in an outer diameter reduced portion whose outer diameter gradually decreases from the proximal end side toward the distal end side, and in the axially symmetric transparent member corresponding to the outer diameter reduced portion, Including a hollow portion whose inner diameter gradually increases from the side toward the tip side,
The LED module according to [2], wherein the thickness changing portion forms the condenser lens.
[4] The LED module according to [3], wherein the axially symmetric light scattering member is applied and formed on a peripheral wall of the hollow portion.
[5] The LED module according to any one of [1] to [4], wherein the emission spectrum satisfies the following relational expression (I):
Relational expression (I):
−0.15 ≦ [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V ( λmax2))] ≦ + 0.15
(In relational expression (I),
P (λ): emission spectrum of the white light source of the present invention
B (λ): emission spectrum of black body radiation showing the same color temperature as a white light source
V (λ): Spectrum of spectral luminous efficiency
λmax1: wavelength at which P (λ) × V (λ) is maximum
λmax2: wavelength at which B (λ) × V (λ) is maximum
λ is a wavelength and is 380 nm ≦ λ ≦ 780 nm).
[6] The LED module according to any one of [1] to [4 ], wherein the emission spectrum satisfies the following relational expression (II):
Relational formula (II):
−0.10 ≦ [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V ( λmax2))] ≦ + 0.10
(In relational expression (II),
P (λ): emission spectrum of the white light source of the present invention
B (λ): emission spectrum of black body radiation showing the same color temperature as a white light source
V (λ): Spectrum of spectral luminous efficiency
λmax1: wavelength at which P (λ) × V (λ) is maximum
λmax2: wavelength at which B (λ) × V (λ) is maximum
λ is a wavelength and is 380 nm ≦ λ ≦ 780 nm).
[7] The LED light source includes at least one LED chip that emits primary light in an ultraviolet or purple region, and a phosphor layer that absorbs primary light from the LED chip and emits secondary light in a visible light region. The LED module according to any one of [1] to [6].
[8] The LED module according to any one of [1] to [7], including at least two types of LED light sources that emit white light having different color temperatures.
[9] The LED module according to [7] or [8], wherein the phosphor layer is made of at least four kinds of phosphors of a blue phosphor, a green phosphor, a yellow phosphor, and a red phosphor.
[10] The blue phosphor is a europium activated alkaline earth chlorophosphate phosphor represented by the following chemical formula (A), and a europium activated alkaline earth magnesium aluminate phosphor represented by the following chemical formula (B): [9] The LED module according to [9], wherein the LED module is at least one phosphor selected from the group consisting of:
Chemical formula (A):
_{(Sr 1-xyxz Ba x Ca} y Eu z) 5 (PO 4) 3 Cl
(Where 0 ≦ x <0.3, 0 ≦ y <0.1, 0.005 ≦ z <0.15)
Chemical formula (B):
_{(Ba 1-xyxz Sr x Ca} y Eu z) MgAl 10 O 17
(Where x <0.5, y <0.1, 0.05 <z <0.4).
[11] The green phosphor is selected from the group consisting of a europium activated orthosilicate phosphor represented by the following chemical formula (D) and a europium activated strontium sialon phosphor represented by the following chemical formula (E): The LED module according to [9] or [10], wherein the LED module is at least one phosphor.
Chemical formula (D):
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4
(Where 0.2 ≦ x ≦ 0.6, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02)
Chemical formula (E):
(Sr _1-x Eu _x ) _α Si _β Al _γ O _δ N _ω
(Where 0 <x <1, 0 <α ≦ 3, 12 ≦ β ≦ 14, 2 ≦ γ ≦ 3.5, 1 ≦ δ ≦ 3, 20 ≦ ω ≦ 22).
[12] The yellow phosphor is selected from the group consisting of a europium activated orthosilicate phosphor represented by the following chemical formula (F) and a cerium activated strontium sialon phosphor represented by the following chemical formula (G): The LED module according to any one of [9] to [11], wherein the LED module is at least one phosphor.
Chemical formula (F):
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4
(Where 0 ≦ x ≦ 0.3, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02)
Chemical formula (G):
_{(M 1-x Ce x)} 2y Al z Si 10-z O u N w
(Where 0 <x ≦ 1, 0.8 ≦ y ≦ 1.1, 2 ≦ z ≦ 3.5, u ≦ 1, 1.8 ≦ z−u, 13 ≦ u + w ≦ 15, element M is Sr And a part of Sr may be substituted with at least one selected from Ba, Ca, and Mg).
[13] The red phosphor is selected from the group consisting of a europium activated strontium sialon phosphor represented by the following chemical formula (H) and a europium activated calcium strontium oxynitride phosphor represented by the following chemical formula (I) The LED module according to any one of [9] to [12], which is at least one kind of phosphor.
Chemical formula (H):
(Sr _1-x Eu _x ) _α Si _β Al _γ OδN _ω
(Where 0 <x <1, 0 <α ≦ 3, 5 ≦ β ≦ 9, 1 ≦ γ ≦ 5, 0.5 ≦ δ ≦ 2, 5 ≦ ω ≦ 15)
Chemical formula (I):
(Ca _1-xy Sr _x Eu _y ) SiAlN ₃
(Where 0 ≦ x <0.4, 0 <y <0.5).
[14] The LED light source has a light emitting surface with an area C, and has a light distribution that is substantially symmetric about a light distribution symmetry axis substantially orthogonal to the light emitting surface.
The axially symmetric transparent member has a first symmetry axis that substantially coincides with the light distribution symmetry axis of the LED light source, and is symmetric with respect to the first symmetry axis;
The axisymmetric light scattering member has a second symmetry axis that substantially coincides with the orientation symmetry axis of the LED light source, and has a bottom surface diameter d ₁ and a length L ₁ along the second symmetry axis. The LED light source, the axially symmetric light scattering member, the closest distance L _2, and the area C of the light emitting surface of the LED light source are expressed by the following formula (1): Satisfy the relationship represented by

The length L ₁ of the axisymmetric light scattering member along the second symmetry axis and the absorption coefficient μ (1 / mm) of the axisymmetric light scattering member satisfy the relationship of the following formula (2):

The diameter d ₁ of the bottom surface of the axisymmetric light scattering member, the closest distance L _2, and the refractive index n of the axisymmetric transparent member satisfy the relationship of the following formula (3):

The cross section of the axisymmetric light scattering member perpendicular to the second symmetry axis is included in the cross section of the axisymmetric transparent member in this cross section,
A projected image obtained by projecting the axially symmetric transparent member toward the light emitting surface of the LED light source along the second axis of symmetry overlaps the light emitting surface of the LED light source [1] to [13] ] Any LED module.
[15] The LED module according to any one of [1] to [14], wherein the axially symmetric transparent member is cylindrical.
[16] the diameter d ₀ of the axis of symmetry transparent member, the diameter d1 of the bottom surface of the axially symmetric light scattering member, and the length L ₁ of the axially symmetric light scattering member along the second axis of symmetry, the [15] The white LED module according to [15], wherein the closest distance between the light emitting surface of the LED light source and the light scattering member and L2 satisfy the relationship of the following formula (4).

[17] [1] to [16] A heat dissipation housing that is connected to the globe including the LED module and is thermally connected to the LED module; A lighting device further comprising a power supply circuit for conversion and a base connected to the heat radiating casing and supplied with electric power from the outside.

  DESCRIPTION OF SYMBOLS 1 ... Illuminating device, 2 ... Globe, 3 ... Base, 4 ... Radiation housing (heat sink), 5 ... Screw, 6 ... Lens holding member, 10 ... LED module, 11 ... Substrate, 12, 12a, 12b, 12c ... Fluorescence Body layer, 13 ... LED light source, 14 ... axisymmetric transparent member, 14h ... hollow portion, 15 ... axisymmetric light scattering member, 15e ... bottom surface, 16 ... thickness changing portion, 18 ... light emitting surface (light emitting surface), 20a , 20b, 20c ... partition wall, 21, 22, 23 ... LED chip group, 24, 25, 26 ... LED chip, 27a, 27b, 27c, 27d ... electrode, 40 ... external power supply, 42 ... lighting circuit (built-in converter), 42a, 42b ... terminals

Claims (14)

A visible light LED light source having a light emitting surface that emits visible light as emitted light, a visible light transmissive axisymmetric transparent member provided so as to cover the LED light source, and the interior of the transparent member spaced from the LED light source An axially symmetric light scattering member that scatters visible light incident from the LED light source through the transparent member and emits the visible light to the outside of the axially symmetric transparent member,
The light scattering member is disposed such that a projection image projected in parallel toward the light emitting surface overlaps at least a part of the light emitting surface, and the emitted light has the following relationship in a wavelength region of 380 nm to 780 nm. shows an emission spectrum distribution successive satisfying formula (I),
In the transparent member, a portion surrounding the light scattering member forms a condenser lens,
The axially symmetric transparent member has a side surface that substantially totally reflects the emitted light emitted from the LED light source, and a thickness change portion in which the thickness gradually decreases from the base end side toward the tip end side,
The thickness change portion is formed in an outer diameter reduced portion whose outer diameter gradually decreases from the proximal end side toward the distal end side, and in the axially symmetric transparent member corresponding to the outer diameter reduced portion, Including a hollow portion whose inner diameter gradually increases from the side toward the tip side,
The LED module, wherein the thickness changing portion forms the condenser lens .
Relational expression (I):
−0.15 ≦ [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V ( λmax2))] ≦ + 0.15
(In relational expression (I),
P (λ): emission spectrum of the white light source of the present invention,
B (λ): emission spectrum of black body radiation showing the same color temperature as the white light source,
V (λ): spectrum of spectral luminous efficiency,
λmax1: a wavelength at which P (λ) × V (λ) is maximum,
λmax2: wavelength at which B (λ) × V (λ) is maximized,
λ is a wavelength and is 380 nm ≦ λ ≦ 780 nm). LED module according to claim 1, wherein said axis of symmetry light scattering member, characterized in that it is applied and formed on the peripheral wall of the hollow portion. LED module according to claim 1 or 2, characterized in that the emission spectrum satisfies the following relational expression (II).
Relational formula (II):
−0.10 ≦ [(P (λ) × V (λ)) / (P (λmax1) × V (λmax1)) − (B (λ) × V (λ)) / (B (λmax2) × V ( λmax2))] ≦ + 0.10
(In relational expression (II),
P (λ): Emission spectrum of the white light source of the present invention B (λ): Emission spectrum of black body radiation showing the same color temperature as the white light source V (λ): Spectrum of spectral luminous efficiency λmax1: P (λ) × Wavelength at which V (λ) is maximum λmax2: Wavelength at which B (λ) × V (λ) is maximum λ is a wavelength, 380 nm ≦ λ ≦ 780 nm). The LED light source includes at least one LED chip that emits primary light in an ultraviolet or purple region, and a phosphor layer that absorbs primary light from the LED chip and emits secondary light in a visible light region. LED module according to any one of claims 1 to 3, characterized. LED module according to any one of claims 1 to 4, characterized in that it comprises at least two LED light sources emitting white light of different color temperatures. The phosphor layer is a blue phosphor, green phosphor, yellow phosphor, LED module according to claim 4 or 5, characterized in that it consists of at least four kinds of phosphors of the red phosphor. The blue phosphor comprises a europium-activated alkaline earth chlorophosphate phosphor represented by the following chemical formula (A) and a europium-activated alkaline earth magnesium aluminate phosphor represented by the following chemical formula (B) The LED module according to claim 6 , wherein the LED module is at least one phosphor selected from the group consisting of:
Chemical formula (A):
_{(Sr 1-xyxz Ba x Ca} y Eu z) 5 (PO 4) 3 Cl
(Where 0 ≦ x <0.3, 0 ≦ y <0.1, 0.005 ≦ z <0.15)
Chemical formula (B):
_{(Ba 1-xyxz Sr x Ca} y Eu z) MgAl 10 O 17
(Where x <0.5, y <0.1, 0.05 <z <0.4). The green phosphor is at least one selected from the group consisting of a europium activated orthosilicate phosphor represented by the following chemical formula (D) and a europium activated strontium sialon phosphor represented by the following chemical formula (E) LED module according to claim 6 or 7, characterized in that the a fluorophore.
Chemical formula (D):
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4
(Where 0.2 ≦ x ≦ 0.6, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02)
Chemical formula (E):
(Sr _1-x Eu _x ) _α Si _β Al _γ O _δ N _ω
(Where 0 <x <1, 0 <α ≦ 3, 12 ≦ β ≦ 14, 2 ≦ γ ≦ 3.5, 1 ≦ δ ≦ 3, 20 ≦ ω ≦ 22). The yellow phosphor is at least one selected from the group consisting of a europium activated orthosilicate phosphor represented by the following chemical formula (F) and a cerium activated strontium sialon phosphor represented by the following chemical formula (G) The LED module according to any one of claims 6 to 8 , wherein the LED module is a phosphor.
Chemical formula (F):
_{(Sr 1-xyzu Ba x Mg} y Eu z Mn u) 2 SiO 4
(Where 0 ≦ x ≦ 0.3, 0.020 ≦ y ≦ 0.105, 0.01 ≦ z ≦ 0.25, 0.0005 ≦ u ≦ 0.02)
Chemical formula (G):
_{(M 1-x Ce x)} 2y Al z Si 10-z O u N w
(Where 0 <x ≦ 1, 0.8 ≦ y ≦ 1.1, 2 ≦ z ≦ 3.5, u ≦ 1, 1.8 ≦ z−u, 13 ≦ u + w ≦ 15, element M is Sr And a part of Sr may be substituted with at least one selected from Ba, Ca, and Mg). The red phosphor is at least one selected from the group consisting of a europium activated strontium sialon phosphor represented by the following chemical formula (H) and a europium activated calcium strontium oxynitride phosphor represented by the following chemical formula (I) LED module according to any one of claims 6-9, characterized in that a phosphor species.
Chemical formula (H):
(Sr _1-x Eu _x ) _α Si _β Al _γ OδN _ω
(Where 0 <x <1, 0 <α ≦ 3, 5 ≦ β ≦ 9, 1 ≦ γ ≦ 5, 0.5 ≦ δ ≦ 2, 5 ≦ ω ≦ 15)
Chemical formula (I):
(Ca _1-xy Sr _x Eu _y ) SiAlN ₃
(Where 0 ≦ x <0.4, 0 <y <0.5). The LED light source has a light emitting surface with an area C, and has a light distribution that is substantially symmetrical about a light distribution symmetry axis that is substantially orthogonal to the light emitting surface.
The axially symmetric transparent member has a first symmetry axis that substantially coincides with the light distribution symmetry axis of the LED light source, and is symmetric with respect to the first symmetry axis;
The axisymmetric light scattering member has a second symmetry axis that substantially coincides with the orientation symmetry axis of the LED light source, and has a bottom surface diameter d ₁ and a length L ₁ along the second symmetry axis. The LED light source, the axially symmetric light scattering member, the closest distance L _2, and the area C of the light emitting surface of the LED light source are expressed by the following formula (1): Satisfy the relationship represented by

The length L ₁ of the axisymmetric light scattering member along the second symmetry axis and the absorption coefficient μ (1 / mm) of the axisymmetric light scattering member satisfy the relationship of the following formula (2):

The diameter d ₁ of the bottom surface of the axisymmetric light scattering member, the closest distance L _2, and the refractive index n of the axisymmetric transparent member satisfy the relationship of the following formula (3):

The cross section of the axisymmetric light scattering member perpendicular to the second symmetry axis is included in the cross section of the axisymmetric transparent member in this cross section,
Along said second axis of symmetry, the projected image obtained by projecting the axis of symmetry transparent member toward the light emitting surface of the LED light source of claim 1 to 10, characterized in that overlaps the light emitting surface of the LED light source The LED module as described in any one. LED module according to any one of claims 1 to 10 wherein the axially symmetric transparent member is characterized by a cylindrical shape. The diameter d ₀ of the axisymmetric transparent member, the diameter d ₁ of the bottom surface of the axisymmetric light scattering member, the length L ₁ of the axisymmetric light scattering member along the second symmetry axis, and the LED light source 13. The white LED module according to claim 12 , wherein the closest distance between the light emitting surface and the light scattering member and L 2 satisfy the relationship of the following formula (4).

A heat dissipating case connected to the globe containing the LED module according to any one of claims 1 to 13 and thermally connected to the LED module, and an alternating current converted to direct current included in the heat dissipating case. A lighting device further comprising a power supply circuit for conversion and a base connected to the heat radiating casing and supplied with electric power from the outside.

Images