JP2012028068A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device excellent in higher heat radiation at a nearer portion to the light-emitting device.SOLUTION: The light source device 1 is provided with a mounting substrate 2 having a first metal layer 23 which is of a plate shape, is formed on its upper surface, and is composed of a metal material, and a plurality of light-emitting devices 4 which are mounted on an upper surface side of the mounting substrate 2 in contact with the metal layer 23 and have light-emitting diode elements. On the mounting substrate 2, there are provided a plurality of heat transmission parts 25 as thermal vias which penetrate the substrate together with the first metal layer 23 in the thickness direction and have a function to transmit the heat generated by each of the light-emitting devices 4 to a lower surface side of the mounting substrate 2. Further, an arrangement density of the heat transmission parts 25 is higher at a nearer portion to the light-emitting device 4 than a farther portion from the light-emitting device 4 in a plane direction of the mounting substrate 2.

Description

  The present invention relates to a light source device.

  A so-called “LED bulb” having a light emitting diode (LED) element is known. As this LED bulb, a plurality of light emitting diode elements, a substrate on which these light emitting diode elements are arranged in a matrix, a cylindrical housing for housing the light emitting diode elements together with the light emitting diode elements, and a base end portion of the housing There is one provided with a cap and a cover as a lid body installed at the tip of the housing (for example, see Patent Document 1).

  In the LED bulb described in Patent Document 1, the substrate is disposed orthogonal to the central axis of the housing. And the board | substrate arrange | positioned in this way is supported by the ring-shaped support member fitted to the inner peripheral part of a housing.

  By the way, since the light emitting diode element generates heat as it emits light, the LED bulb needs to release the heat. However, in the light bulb described in Patent Document 1, the substrate is simply a metal plate (aluminum substrate), and the substrate on which the current LED is directly mounted conducts heat from each light-emitting diode element to the outside sufficiently and reliably. As a result, there is a problem that heat radiation becomes insufficient.

JP 2006-156187 A

  The objective of this invention is providing the light source device excellent in heat dissipation.

Such an object is achieved by the present inventions (1) to (17) below.
(1) A substrate having a plate shape and having a metal layer formed on one surface side and made of a metal material;
Including at least one light emitting device mounted on one surface of the substrate so as to be in contact with the metal layer and having a light emitting diode element;
The substrate is provided with a number of heat transfer portions that penetrate the entire metal layer in the thickness direction and have a function of transferring heat generated in the light emitting device to the other surface side of the substrate,
The light source device according to claim 1, wherein a density of the heat transfer units is higher in a proximal portion proximal to the light emitting device than in a distal portion distal to the light emitting device in the surface direction of the substrate.

(2) The light source device according to (1), wherein the arrangement density changes stepwise or gradually along a surface direction of the substrate.

(3) The light source device according to (1) or (2), wherein the arrangement density at the proximal portion is 1.1 to 100 times the arrangement density at the distal portion.

(4) In the proximal portion and the distal portion, the proximal portion is a high-density region having a high arrangement density, and the distal portion has a low arrangement density that is lower than the high-density region. Density region,
The light source device according to (3), wherein the high density region is a region within a range of 5 to 100 mm with the light emitting device as a center.

(5) Each said heat-transfer part is a light source device in any one of said (1) thru | or (4) comprised by the through-hole, respectively.

(6) The light source device according to (5), wherein an inner metal layer made of a metal material is formed on each inner peripheral surface of each through hole.

(7) The light source device according to (5) or (6), wherein each of the through holes is provided with a conductor post made of a metal material.

(8) Each said heat-transfer part is a light source device in any one of said (1) thru | or (4) comprised by the conductor post comprised with the metal material, respectively.

(9) The metal layer is patterned into a predetermined shape, and has a portion functioning as an electric circuit electrically connected to the light emitting device, and a function of transmitting heat generated in the light emitting device to each heat transfer unit. The light source device according to any one of (1) to (8), including a portion.

(10) The substrate (1) to (9), wherein the substrate is a laminated plate having a substrate layer formed by impregnating a fiber substrate with a resin material, and the metal layer is laminated on the substrate layer. The light source device according to any one of the above.

(11) The light source device according to (10), wherein the fiber base material is a glass fiber base material.
(12) The light source device according to (10) or (11), wherein the substrate is formed on the other surface side and has a back side metal layer made of a metal material.

(13) The heat transfer section has a portion that does not overlap the light emitting device in a plan view, and the occupation ratio of the portion with respect to the entire one surface of the substrate is 0.01% or more. The light source device according to any one of 12).

(14) The heat transfer section has a portion overlapping the light emitting device in plan view, and the occupation ratio of the portion with respect to the area of the light emitting device in plan view is 0.01% or more (1) Thru | or the light source device in any one of (13).

(15) The light source device according to any one of (1) to (14), wherein the metal layer has an occupation ratio of 50% or more with respect to the entire one surface of the substrate.

(16) Any one of (1) to (15), further including a heat dissipating member that is installed on the other surface side of the substrate and dissipates heat from the light emitting device transmitted through the heat transfer units. The light source device described.

(17) The light source device according to any one of (1) to (16), which is used as a backlight of a liquid crystal display device.

  According to the present invention, in the proximal portion proximal from the light emitting device of the substrate, it is promoted that heat from the light emitting device is transmitted to the other surface side of the substrate. And the heat transmitted to the other surface side of the substrate is radiated outward. Therefore, the light source device of the present invention is excellent in heat dissipation.

It is a top view which shows 1st Embodiment of the light source device of this invention. 2 is an enlarged detail view of a light emitting device of the light source device shown in FIG. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. It is sectional drawing which shows the mounting substrate of the light source device (2nd Embodiment) of this invention. It is sectional drawing which shows the mounting substrate of the light source device (3rd Embodiment) of this invention. It is a top view which shows 4th Embodiment of the light source device of this invention. It is a top view which shows 5th Embodiment of the light source device of this invention. It is a perspective view of the liquid crystal television which incorporated the light source device shown in FIG. FIG. 10 is a schematic partial cross-sectional view of the liquid crystal television shown in FIG. 9.

DESCRIPTION OF EMBODIMENTS Hereinafter, a light source device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<First Embodiment>
FIG. 1 is a plan view showing a first embodiment of a light source device of the present invention, FIG. 2 is an enlarged detailed view of a light emitting device of the light source device shown in FIG. 1 and its surroundings, and FIG. 3 is an A- in FIG. 4 is a sectional view taken along line BB in FIG. 2, FIG. 9 is a perspective view of a liquid crystal television incorporating the light source device shown in FIG. 1, and FIG. 10 is a perspective view of the liquid crystal television shown in FIG. It is a general | schematic fragmentary sectional view. In the following, for convenience of explanation, the upper side in FIGS. 3 and 4 (the same applies to FIGS. 5 and 6) is “upper”, “upper” or “table”, and the lower side is “lower”, “lower” Or “back”, the left side of FIG. 10 is called “front”, and the right side is called “back”.

  As shown in FIG. 9, the light source device 1 is built in a liquid crystal television 100 which is a liquid crystal display device, and can be used as a backlight thereof.

  The liquid crystal television 100 includes a light source device 1, a display unit (liquid crystal cell) 101 disposed on the front side of the light source device 1, a housing 102 that houses the light source device 1 and the display unit 101, and legs that support the housing 102. Part (stand) 103.

  As shown in FIG. 10, the display unit 101 includes a polarizing plate 104, a glass substrate 105, a color filter 106, a protective film 107, a liquid crystal unit 108, a glass substrate 109, and a polarizing plate 110 in order from the front side. . Furthermore, between the polarizing plate 110 and the light source device 1, various optical films (not shown) such as a diffusion plate, a diffusion sheet, a prism sheet, a brightness enhancement film, and a reflective polarizing plate may be provided. The liquid crystal unit 108 includes a thin film transistor (TFT) as a switching element and a liquid crystal layer made of a quasi-isotropic liquid crystal material or the like. The display unit 101 generates an electric field in the thin film transistor and changes the alignment state of the liquid crystal material in the liquid crystal layer by the electric field, thereby changing the color tone to be visually recognized. And the light from the light source device 1 which is a backlight permeate | transmits the display part 101, and the image displayed on the said display part 101 can be visually recognized.

  As shown in FIGS. 1 and 2, the light source device 1 includes a plurality of light emitting devices 4 and a mounting substrate (substrate) 2 on which these light emitting devices 4 are mounted together. Hereinafter, the configuration of each unit will be described.

  Since each light-emitting device 4 has the same configuration, one light-emitting device 4 will be representatively described below.

  The light emitting device 4 generates light emission by electroluminescence (EL) effect and light emission by fluorescence.

  As shown in FIG. 3, the light emitting device 4 covers a package 41 having a recess 411, a light emitting diode element (LED chip) 42 provided on the bottom surface of the recess 411 of the package 41, and the light emitting diode element 42. A translucent resin portion 43 enclosed in the recess 411 and a pair of external terminals 44 provided on the bottom of the package 41 are provided.

  The package 41 is a small piece made of an insulating material such as a resin material or a ceramic material. The package 41 is provided with wiring (not shown) that electrically connects the light emitting diode element 42 and the pair of external terminals 44.

  The light emitting diode element 42 is formed by forming a semiconductor such as GaAlN, ZnS, ZnSe, SiCGaP, GaAlAs, AlN, InN, AlInGaP, InGaN, GaN, and AlInGaN on the package 41 as a light emitting layer. In the present embodiment, the light emitting diode element 42 that emits light having a wavelength that can excite a phosphor material contained in the light-transmitting resin portion 43 described later is used. More specifically, the light emitting diode element 42 that emits blue light is used.

  The translucent resin portion 43 is composed mainly of a resin material such as an epoxy resin, a modified epoxy resin, a silicone resin, a modified silicone resin, an acrylate resin, a urethane resin, or a polyimide resin having transparency.

  In the present embodiment, the translucent resin portion 43 includes a phosphor material that is excited by the light from the light emitting diode element 42 and emits yellow light.

  The translucent resin portion 43 has a function of protecting the light emitting diode element 42 from external force, dust, moisture, and the like.

  The pair of external terminals 44 is composed of a conductive material as a main material. One external terminal 44 is an anode electrode (anode), and the other external terminal 44 is a cathode electrode (cathode). . Each external terminal 44 is composed mainly of a metal material such as Al, Ti, Fe, Cu, Ni, Ag, Au, and Pt. Each external terminal 44 is electrically connected (contacted) to a circuit pattern 231 (first metal layer 23) provided on the mounting substrate 2 by solder (not shown). Furthermore, the circuit pattern 231 is electrically connected to a power source (not shown).

  In such a light emitting device 4, when a voltage is applied to the light emitting diode element 42 via the pair of external terminals 44, light emission based on the electroluminescence effect occurs in the light emitting diode element 42. By this light emission, the light is transmitted through the translucent resin portion 43 and emitted to the outside. At this time, a part of the light is reflected on the inner wall surface of the recess 411 of the package 41, then passes through the translucent resin portion 43 and is emitted to the outside.

  Further, the light emitting device 4 emits blue light by the EL effect of the light emitting diode element 42, and the translucent resin portion 43 is excited by a part of the blue light to emit yellow light by fluorescence, and has a complementary color relationship. White light is emitted by mixing these blue light and yellow light.

  In addition, the light emitting diode element 42 is not limited to the above-mentioned thing, For example, a monochromatic light emitting diode element, such as red, blue, and green, may be sufficient. In this case, the phosphor material may be omitted from the translucent resin portion 43. The light emitting device 4 may have a plurality of light emitting diode elements. In this case, the emission colors may be the same or different from each other.

  Such a light emitting device 4 is mounted on the mounting substrate 2. As shown in FIG. 1, the mounting substrate 2 has a long plate shape. The light emitting devices 4 are arranged at equal intervals along the longitudinal direction of the mounting substrate 2.

  As shown in FIGS. 3 and 4, the mounting substrate 2 includes a first base material layer (base material layer) 21 and second base material layers (bases) formed on both surfaces of the first base material layer, respectively. Material layers) 22a and 22b, a first metal layer (metal layer (front side metal layer)) 23 formed on the upper surface (one surface) of the second base material layer 22a, and a second base material layer 22b It is the laminated board which has the 2nd metal layer (back side metal layer) 24 formed in the lower surface (other side) of this. This mounting substrate 2 is an example using a so-called glass composite substrate “CEM-3”.

The thickness t _total of the entire mounting substrate 2 is not particularly limited, and is preferably 0.1 to 2.0 mm, for example, and more preferably 0.4 to 1.2 mm. The thickness _{t 1} of the first substrate layer 21, the thickness _{t 2} of the second base material layer 22a and 22b, the thickness _{t 3} of the first metal layer 23, the second metal layer 24 magnitude relationship between the thickness _{t 4,} from the viewpoint of thermal conductivity, it is preferred that _{t 1 ≧ t 2> t 3} . Moreover, it is preferable that t ₃ = t ₄ from the viewpoint of suppressing the warpage of the mounting substrate 2.

  The first base material layer 21, the second base material layer 22a, and the second base material layer 22b are layers formed by impregnating a fiber base material with a resin material, respectively.

  The fiber substrate is not particularly limited, and examples thereof include glass fiber substrates such as glass woven fabrics, glass non-woven fabrics, and glass papers, and woven fabrics made of organic fibers such as paper (pulp), aramid, polyester, and fluororesin. Examples include woven fabrics, nonwoven fabrics, mats and the like made of nonwoven fabrics, metal fibers, carbon fibers, mineral fibers and the like. These substrates may be used alone or in combination. In particular, it is preferable to use a glass non-woven cloth for the first base material layer 21 and a glass woven cloth for the second base material layers 22a and 22b.

  The resin material to be impregnated into the fiber base material is preferably a thermosetting resin, such as an epoxy resin, a phenol resin, a urea resin, a melamine resin, a polyester (unsaturated polyester) resin, a polyimide resin, a silicone resin, and a polyurethane resin. Among them, one or two or more of these can be mixed and used, and among these, an epoxy resin is more preferable.

  Further, when the fiber base material constituting the first base material layer 21 is impregnated with a resin material, the resin material includes, for example, a metal oxide such as alumina, a metal hydroxide such as aluminum hydroxide, and nitriding. It is also possible to fill an electrically insulating and highly heat conductive filler (inorganic filler) typified by a nitride such as boron.

  In the mounting substrate 2, the heat generated as each light emitting device 4 emits light is transmitted from the first metal layer 23 to the second base material layer 22 a, the first base material layer 21, and the second base material layer. It is reliably transmitted in the order of 22 b, that is, in the direction away from the light emitting device 4 (the surface direction and the thickness direction of the mounting substrate 2), and is radiated by the second metal layer 24. Thus, the mounting substrate 2 (light source device 1) is excellent in heat dissipation.

  Further, as described above, it is preferable to use a glass non-woven cloth for the first base material layer 21 and use a glass woven cloth for the second base material layers 22a and 22b. Since the glass non-woven fabric can carry a larger amount of a resin material having a higher thermal conductivity than the glass woven fabric, the glass non-woven fabric is the first base material layer 21 located on the innermost side of the mounting substrate 2, particularly in the surface direction. The heat from the light emitting device 4 is diffused. Thereby, heat dissipation efficiency improves.

The thickness _{t 1,} not particularly limited, for example, is preferably from 0.1 to 1.2 mm, and more preferably 0.2 to 0.8 mm.

The thickness _{t 2,} not particularly limited, for example, is preferably from 0.04～0.4Mm, and more preferably 0.1 to 0.2 mm.

  A first metal layer 23 is laminated on the second base material layer 22a, and a second metal layer 24 is laminated on the second base material layer 22b. Each of the first metal layer 23 and the second metal layer 24 is a layer made of a metal material.

  The metal material constituting the first metal layer 23 is not particularly limited, and for example, one type selected from the group consisting of copper, iron, aluminum, indium, tin, lead, silver, zinc, bismuth, and antimony or Examples thereof include conductive materials obtained by combining two or more kinds, and among these, copper is particularly preferable. Copper is also excellent in thermal conductivity, and can reliably transfer the heat from each light emitting device 4 to the second base material layer 22 a under the first metal layer 23.

  The metal material constituting the second metal layer 24 is not particularly limited. For example, in addition to the metal material constituting the first metal layer 23, aluminum can also be used. Aluminum and copper are excellent in thermal conductivity, and can reliably dissipate heat transmitted through the second base material layer 22b.

  The first metal layer 23 and the second metal layer 24 may be made of the same metal material or may be made of different metal materials. In the case where the first metal layer 23 and the second metal layer 24 are made of the same metal material, for example, each of the first metal layer 23 and the second metal layer 24 can be made of copper. One metal layer 23 can be made of copper, and the second metal layer 24 can be made of aluminum.

  Further, the method for forming the first metal layer 23 and the second metal layer 24 is not particularly limited, and examples thereof include metal foil bonding (adhesion), metal plating, vapor deposition, sputtering, and printing. .

  As shown in FIG. 2, the first metal layer 23 is patterned into a predetermined shape. Thereby, the 1st metal layer 23 can be divided into the circuit pattern 231 which functions as an electric circuit, and the heat transfer pattern 232 which has a heat transfer function. The circuit pattern 231 is electrically connected to the external terminal 44 of each light emitting device 4 via, for example, solder. Thereby, power is supplied via the circuit pattern 231. The heat transfer pattern 232 is in contact with (in contact with) the back surface of the package 41 of each light emitting device 4. Thereby, the heat generated in each light emitting device 4 can be reliably transmitted to each heat transfer section 25 described later via the heat transfer pattern 232.

  In addition, it does not specifically limit as a patterning method to the 1st metal layer 23, For example, methods, such as an etching, printing, masking, can be used. By such a patterning method, the circuit pattern 231 and the heat transfer pattern 232 can be collectively formed.

  In addition, the first metal layer 23 preferably has, for example, an occupation ratio with respect to the entire top surface of the mounting substrate 2 of 50% or more, more preferably 80 to 99%. Thereby, the area of the heat transfer pattern 232 can be ensured to such an extent that the heat generated in each light emitting device 4 can be reliably transmitted to each heat transfer section 25. Further, when etching is used as a patterning method for the first metal layer 23, the portion of the first metal layer 23 to be removed by the etching is relatively small. Can do.

The thickness _{t 3,} not particularly limited, for example, is preferably from 0.008～0.21Mm, and more preferably 0.012～0.105Mm.

The thickness _{t 4,} is not particularly limited, for example, is preferably from 0.008～2Mm, and more preferably 0.012～1.5Mm.

  As shown in FIG. 1, the mounting substrate 2 is provided with a large number of heat transfer sections 25 arranged in a matrix. Each heat transfer section 25 is a thermal via having a function of transferring heat generated in the light emitting device 4 to the lower surface side of the mounting substrate 2, that is, to the second metal layer 24.

  As shown in FIG. 3 and FIG. 4, each heat transfer section 25 includes a through hole 251 that penetrates the mounting substrate 2 in the thickness direction together with the first metal layer 23, and an inner peripheral surface of the through hole 251. The inner metal layer 252 is formed. The inner metal layer 252 is connected (contacted) to the first metal layer 23 and the second metal layer 24, respectively. With the heat transfer section 25 having such a configuration, heat from each light emitting device 4 is reliably transferred to the second metal layer 24 through the air in the through hole 251 and the inner metal layer 252 around the air. Then, heat is radiated from the second metal layer 24. Further, by providing the through hole 251, the surface area of the second metal layer 24 (or the first metal layer 23) is improved, and the heat dissipation efficiency of the light emitting device 4 is improved.

  The shape of each through hole 251 in plan view is a circle in the present embodiment, but is not limited to this, and may be, for example, a polygon such as an ellipse or a rectangle.

  A method for forming the through hole 251 is not particularly limited, and examples thereof include drilling, router processing, punching processing, and laser processing.

  The internal metal layer 252 is made of a metal material, and for example, the same material as that of the first metal layer 23 and the second metal layer 24 can be used. A method for forming the internal metal layer 252 is not particularly limited, and examples thereof include metal plating, vapor deposition, and sputtering.

  As shown in FIG. 1, in the heat transfer section 25 having the above-described configuration, the arrangement density changes stepwise along the surface direction of the mounting substrate 2, that is, the arrangement density is high or low (dense / dense). ) Thus, the mounting substrate 2 is divided into a high density region 26 in which the heat transfer unit 25 is disposed at a high density and a low density region 27 in which the heat transfer unit 25 is disposed at a lower density than the high density region 26. The high density region 26 is a proximal portion proximal from the light emitting device 4 in the surface direction of the mounting substrate 2, and the low density region 27 is a distal portion distal to the light emitting device 4.

  And the arrangement | positioning density of the heat-transfer part 25 in the high-density area | region 26 (proximal part) is 1.1-100 times the arrangement | positioning density of the heat-transfer part 25 in the low-density area | region 27 (distal part). It is preferable that it is 2 to 25 times.

  In addition, when the light emitting device 4 has a side of 5 to 20 mm square, for example, the high density region 26 is preferably a region within a range of 5 to 100 mm centering on the light emitting device 4. A region within the range is more preferable.

  Since the arrangement density is high and low, heat transfer from the light emitting device 4 to the second metal layer 24 is particularly promoted in the high density region 26 where the light emitting device 4 is arranged. Then, due to the synergistic effect of this heat transfer promotion and the heat transfer action to the second metal layer 24 in the first base material layer 21 and the second base material layers 22a and 22b described above, It is reliably transmitted by the second metal layer 24 and radiated by the second metal layer 24. Thus, the light source device 1 is extremely excellent in heat dissipation.

  As shown in FIG. 2, the heat transfer section 25 in the high-density region 26 has three heat transfer sections 25 that overlap with the light emitting device 4 in plan view. These heat transfer sections 25 preferably have an occupation ratio with respect to the area of the light emitting device 4 in plan view of 0.01% or more, and more preferably 0.02 to 50%. Thereby, the heat from the light emitting device 4 can be directly guided to the heat transfer section 25, and thus the thermal conductivity in the high density region 26 is improved. In the configuration shown in FIG. 2, the number of the heat transfer units 25 that overlap with the light emitting device 4 in the plan view is three, but is not limited to this, for example, one, two, or four or more. May be. Further, in the high density region 26, the heat transfer section 25 that overlaps the light emitting device 4 in plan view may be omitted.

  The heat transfer unit 25 also includes a heat transfer unit 25 that does not overlap the light emitting device 4 in plan view. These heat transfer parts 25 preferably have an occupation ratio of 0.01% or more with respect to the entire top surface of the mounting substrate 2, and more preferably 0.02 to 10%. Thereby, the heat generated from each light emitting device 4 (light emitting diode element 42) can be reliably transmitted to the outside, so that the light emission efficiency of each light emitting device 4 can be improved and the drive voltage can be lowered. Thereby, the light source device 1 with high heat dissipation, high luminance, and long life can be provided.

<Second Embodiment>
FIG. 5 is a cross-sectional view showing a mounting substrate of the light source device (second embodiment) of the present invention.

Hereinafter, the second embodiment of the light source device of the present invention will be described with reference to this drawing, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.
This embodiment is the same as the first embodiment except that the configuration of the heat transfer section is different.

  As shown in FIG. 5, in the light source device 1 </ b> A, rod-shaped conductor posts (thermal conductive conductor posts) 253 are respectively disposed in the through holes 251 of the heat transfer units 25. In the present embodiment, each heat transfer section 25 includes a conductor post 253 and an internal metal layer 252.

  The conductor post 253 is made of a metal material, and for example, the same material as the constituent material of the first metal layer 23 and the second metal layer 24 can be used.

  Examples of the method of arranging the conductor post 253 in the through hole 251 include a method of filling the through hole 251 with a metal material, a method of inserting a rod-shaped member made of a metal material into the through hole 251, specifically a copper paste Examples thereof include a method of embedding a metal paste such as silver paste in the through hole 251, a method of using eyelets and rivets, a method of forming the heat transfer portion 25 while forming the through hole 251 with bolts, screws, and the like.

  Since the metal material is generally higher in heat conductivity than air, the conductor posts 253 made of the metal material are arranged, so that the heat of each light emitting device 4 is transferred to the second metal layer 24. Is further promoted.

  In addition, the conductor post 253 is not limited to one made of a metal material, and may be made of a resin material having a relatively high thermal conductivity, for example.

<Third Embodiment>
FIG. 6 is a cross-sectional view showing a mounting substrate of the light source device (third embodiment) of the present invention.

  Hereinafter, the third embodiment of the light source device of the present invention will be described with reference to this figure, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.

  This embodiment is the same as the first embodiment except that the light source device further includes a heat dissipation member.

  As shown in FIG. 6, in the light source device 1 </ b> B, a heat sink (heat radiating member) 3 is fixed to the back surface of the mounting substrate 2. The method for fixing the heat sink 3 is not particularly limited. For example, a method using adhesion (adhesion with an adhesive or a solvent), a method using fusion (thermal fusion, high frequency fusion, ultrasonic fusion, etc.), screws, and the like. Examples include a method by stopping.

The heat sink 3 includes a flat main body 31 and a plurality of heat radiation fins 32 protruding from the back surface of the main body 31. The upper surface of the main body 31 is in contact with the back surface (second metal layer 24) of the mounting substrate 2. Each of the radiation fins 32 is composed of a small piece, and is arranged at equal intervals along the longitudinal direction of the mounting substrate 2. Thereby, the surface area of the heat sink 3 can be sufficiently secured to the extent that heat can be reliably radiated. Therefore, the heat from the light emitting device 4 transmitted to the second metal layer 24 through each heat transfer section 25 can be efficiently radiated by the heat sink 3.
The heat sink 3 may be one in which the heat radiating fins 32 are omitted.

<Fourth embodiment>
FIG. 7 is a plan view showing a fourth embodiment of the light source device of the present invention.

Hereinafter, the fourth embodiment of the light source device of the present invention will be described with reference to this drawing. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.
This embodiment is the same as the first embodiment except that the arrangement of the light emitting devices is different.

  As shown in FIG. 7, in the light source device 1 </ b> C, a plurality of sets of four light emitting devices 4 are arranged in a high density region 26 in, for example, a “rice” shape. The two light emitting devices 4 on the diagonal side emit green monochromatic light. Of the remaining two light emitting devices 4, one light emitting device 4 emits red monochromatic light, and the other light emitting device 4 emits blue monochromatic light. When these light emitting devices 4 emit light, the light source device 1C can emit white light as a whole and adjust the color temperature. Further, the color filter 106 can be omitted from the liquid crystal display device.

  In the light source device 1 </ b> C, similarly to the light source device 1, heat transfer to the second metal layer 24 is promoted in the high-density region 26, and heat is surely radiated from the second metal layer 24.

<Fifth Embodiment>
FIG. 8 is a plan view showing a fifth embodiment of the light source device of the present invention.

Hereinafter, the fifth embodiment of the light source device of the present invention will be described with reference to this drawing. However, the difference from the above-described embodiment will be mainly described, and description of similar matters will be omitted.
This embodiment is the same as the first embodiment except that the arrangement of the heat transfer section is different.

  As shown in FIG. 8, in the light source device 1 </ b> D, a large number of heat transfer sections 25 are arranged radially around the light emitting device 1, and the arrangement density gradually changes along the surface direction of the mounting substrate 2. ing.

  In such a light source device 1D, similarly to the light source device 1, heat transfer to the second metal layer 24 is promoted at the proximal portion of the mounting substrate 2 with respect to the light emitting device 1, and the second metal layer 24 reliably The heat is dissipated.

  The light source device of the present invention has been described above with respect to the illustrated embodiment. However, the present invention is not limited to this, and each part constituting the light source device has an arbitrary configuration that can exhibit the same function. Can be substituted. Moreover, arbitrary components may be added.

  Further, the light source device of the present invention may be a combination of any two or more configurations (features) of the above embodiments.

  In addition to the liquid crystal television, examples of the liquid crystal display device in which the light source device of the present invention can be built include a desktop or notebook personal computer monitor, a mobile phone, a digital camera, and a portable information terminal. Furthermore, the light source device of the present invention can be applied to a light bulb in addition to such a liquid crystal display device. In that case, for example, a light source such as a streetlight (electric light), a traffic light, lighting of a signboard, an electric bulletin board, etc. Can be applied to.

In addition to the substrate using “CEM-3” which is a so-called glass composite substrate, for example, so-called “FR-4” having a layer formed by impregnating a glass woven fabric with an epoxy resin is used. It may be a thing.
The mounting board may be one in which the second metal layer is omitted.

1, 1A, 1B, 1C, 1D Light source device 2 Mounting substrate (substrate)
21 1st base material layer (base material layer)
22a, 22b Second base material layer (base material layer)
23 1st metal layer (metal layer (front side metal layer))
231 Circuit pattern 232 Heat transfer pattern 24 Second metal layer (back side metal layer)
25 Heat transfer portion 251 Through hole 252 Internal metal layer 253 Conductor post (heat conduction conductor post)
26 High-density area 27 Low-density area 3 Heat sink (heat dissipation member)
31 Body 32 Radiating fin 4 Light emitting device 41 Package 411 Recess 42 Light emitting diode element (LED chip)
43 Translucent resin part 44 External terminal 100 Liquid crystal television 101 Display part (liquid crystal cell)
102 Housing 103 Leg (stand)
104 polarizing plate 105 glass substrate 106 color filter 107 protective film 108 liquid crystal part 109 glass substrate 110 polarizing plate t _total , t ₁ , t ₂ , t ₃ , t ₄ thickness

Claims (17)

A substrate having a metal layer made of a metal material formed on one side of the plate,
Including at least one light emitting device mounted on one surface of the substrate so as to be in contact with the metal layer and having a light emitting diode element;
The substrate is provided with a number of heat transfer portions that penetrate the entire metal layer in the thickness direction and have a function of transferring heat generated in the light emitting device to the other surface side of the substrate,
The light source device according to claim 1, wherein a density of the heat transfer units is higher in a proximal portion proximal to the light emitting device than in a distal portion distal to the light emitting device in the surface direction of the substrate.   The light source device according to claim 1, wherein the arrangement density changes stepwise or gradually along a surface direction of the substrate.   The light source device according to claim 1, wherein the arrangement density at the proximal portion is 1.1 to 100 times the arrangement density at the distal portion. In the proximal portion and the distal portion, the proximal portion is a high-density region where the arrangement density is high, and the distal portion is a low-density region where the arrangement density is lower than the high-density region. Yes,
The light source device according to claim 3, wherein the high density region is a region within a range of 5 to 100 mm with the light emitting device as a center.   5. The light source device according to claim 1, wherein each of the heat transfer units is configured by a through hole.   The light source device according to claim 5, wherein an inner metal layer made of a metal material is formed on an inner peripheral surface of each through hole.   The light source device according to claim 5 or 6, wherein a conductor post made of a metal material is disposed in each of the through holes.   5. The light source device according to claim 1, wherein each of the heat transfer units is formed of a conductor post made of a metal material.   The metal layer is patterned into a predetermined shape and includes a portion functioning as an electric circuit electrically connected to the light emitting device, and a portion having a function of transmitting heat generated in the light emitting device to each heat transfer unit. The light source device according to claim 1, which is configured.   10. The substrate according to claim 1, wherein the substrate has a base material layer formed by impregnating a fiber base material with a resin material, and the metal layer is laminated on the base material layer. Light source device.   The light source device according to claim 10, wherein the fiber base material is a glass fiber base material.   The light source device according to claim 10, wherein the substrate has a back side metal layer formed on the other surface side and made of a metal material.   The heat transfer section has a portion that does not overlap the light emitting device in a plan view, and the occupation ratio of the portion with respect to the entire one surface of the substrate is 0.01% or more. The light source device described.   The heat transfer section has a portion overlapping the light emitting device in plan view, and an occupation ratio of the portion with respect to the area of the light emitting device in plan view is 0.01% or more. A light source device according to claim 1.   The light source device according to any one of claims 1 to 14, wherein the metal layer has an occupation ratio of 50% or more with respect to the entire one surface of the substrate.   The light source device according to claim 1, further comprising a heat dissipating member that is installed on the other surface side of the substrate and dissipates heat from the light emitting device transmitted through the heat transfer units.   The light source device according to claim 1, wherein the light source device is used as a backlight of a liquid crystal display device.

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