WO2016199804A1

WO2016199804A1 - Led light source device and projector

Info

Publication number: WO2016199804A1
Application number: PCT/JP2016/067034
Authority: WO
Inventors: 榎本　實; 政道石原; 達伊藤
Original assignee: 株式会社Ｓｔｅｑ
Priority date: 2015-06-08
Filing date: 2016-06-08
Publication date: 2016-12-15
Also published as: JP6735072B2; JP2016105450A

Abstract

[Problem] To provide an LED light source device having a flux distribution angle of 30° or less and having exceptional luminous flux distribution and directionality, and to provide a desktop projector provided with said LED light source device. [Solution] Provided is an LED light source device provided with: a mounting substrate of which at least the surface is metal; a first insulation layer formed on the surface of the mounting substrate; a wiring layer formed as the upper layer of the first insulation layer; and a plurality of LED chips having identical specifications, the LED chips being surface-mounted in a matrix on the mounting substrate, wherein the LED light source is characterized in: being provided with a reflector block that has microreflectors in a quantity identical to that of the LED chips; the microreflectors having bottom openings and upper openings that are larger in diameter than the bottom openings; and the wiring layer being configured from a first electroconductive layer formed by applying a metal paste that contains a penetration-curing resin and a metal powder to the insulation layer and heating the paste, and a second electroconductive layer formed on the upper surface of the first electroconductive layer and endowed with a lower resistance than that of the first electroconductive layer. Also provided is a projector provided with said LED light source device.

Description

LED light source device and projector

The present invention relates to an LED light source device and a projector, and for example, has excellent luminous flux distribution and directivity, and the total luminous flux value from three light sources is 2000 lumens (lm) or more (preferably 3000 lm or more). And a projector including the light source device.

In recent years, many lighting fixtures have been proposed in which the light emitting part is replaced with an LED (Light Emitting Diode), and an LED light source that replaces an ultra-high pressure mercury lamp has also been proposed in a projector.
For example, Patent Document 1 proposes a projector having an optical configuration shown in FIG. Reference numeral 10R is an LED for red light, reference numeral 10G is an LED for green light, reference numeral 10B is an LED for blue light, and the light from each LED is collimated by the collimator lens 12, The light enters each liquid crystal light valve 100, is modulated, and enters the dichroic prism 14. The light synthesized by the dichroic prism 14 is projected onto a screen from a projection lens 16 having a zoom ring 17.

However, a bright projector equivalent to a mercury lamp cannot be provided by light emission from a single LED. Therefore, in Patent Document 2, a light guide body in which the areas of the light incident end face and the light exit end face facing each other are relatively larger than the area of the display region in the irradiated body, and the light incident end face of the light guide body. And a light source having a light emitting area substantially equal to the area of the light incident end face, and the light exit end face of the light guide has a first area having an area substantially equal to the area of the display region of the irradiated object. 1 is formed, and a light output side reflecting member is provided in a region other than the first opening, and the light output side reflection is provided on the light incident side of the light guide in the optical axis direction from the light source. There has been proposed an illuminating device in which a light incident side reflecting member facing the member is provided.

However, in the optical structure of Patent Document 2, the size of the projector body must be huge. On the other hand, when the degree of integration of the LED elements is increased, there is a problem that a doughening phenomenon occurs in which the amount of light at the light emission center portion, in which heat dissipation becomes worse, is particularly reduced. Therefore, the applicants in Patent Document 3 apply a liquid material containing SiO ₂ particles having an average particle diameter of several nanometers to several hundred nanometers and a white inorganic pigment at least on the surface of a substrate whose surface is a metal, and firing. Thus, a semiconductor device that can solve the doughening phenomenon by forming a laminated structure of a white insulating layer and a metal layer has been proposed.

JP 2012-155049 A JP 2014-187026 A Japanese Patent No. 5456209

The present invention provides an LED light source device having a light distribution angle of 30 degrees or less (preferably 26 degrees or less, more preferably 20 degrees or less) and excellent in luminous flux distribution and directivity, and a desktop projector including the light source device. The purpose is to provide. Another object of the present invention is to provide an LED light source device having a total luminous flux value of 2000 lumens (lm) or more and a desktop projector including the light source device.

According to a first aspect of the present invention, there is provided a mounting substrate having at least a metal surface, a first insulating layer formed on the surface of the mounting substrate, a wiring layer formed as an upper layer of the first insulating layer, and a mounting substrate An LED light source device comprising a plurality of LED chips of the same specification, which are surface-mounted on a matrix, and having a reflector block having the same number of micro-reflectors as the LED chips, the micro-reflector having a bottom portion A first opening formed by applying and heating a metal paste containing a resin and metal powder that penetrates and hardens into the insulating layer, and has an opening and an upper opening having a diameter larger than that of the bottom opening; An LED light source device comprising: a conductive layer; and a second conductive layer having a lower resistance than the first conductive layer formed on the upper surface of the first conductive layer.
A second invention is characterized in that, in the first invention, the second insulating layer functioning as a reflective layer as an upper layer of the wiring layer is formed so as to leave an exposed portion exposing the wiring layer. To do.
According to a third invention, in the second invention, the first insulating layer is a porous material obtained by applying a liquid material containing nanoparticulated SiO ₂ and a white inorganic pigment and heating at 160 to 250 ° C. It is characterized by comprising an inorganic white insulating layer.
According to a fourth invention, in the third invention, the second insulating layer is a porous material obtained by applying a liquid material containing nanoparticulated SiO ₂ and a white inorganic pigment and heating at 160 to 250 ° C. It is characterized by comprising an inorganic white insulating layer.
According to a fifth invention, in any one of the second to fourth inventions, the upper opening of the micro-reflector is enlarged in diameter by 70 to 85 ° with respect to the bottom opening, and the distance between the bottom opening and the upper opening is 4 It is ˜8 mm.
According to a sixth invention, in the fifth invention, the micro reflectors are arranged in a staggered manner, the distance between the centers of the micro reflectors is smaller than the diameter of the upper opening, and the upper openings overlap each other. It does not fit.
According to a seventh aspect, in the sixth aspect, the LED chip is connected to the wiring layer through the opening within the range of the pitch upper opening of the micro reflector where the LED chip is disposed. Features.
An eighth invention is characterized in that, in any one of the second to seventh inventions, the light distribution angle is 30 degrees or less, the total luminous flux value is 500 lumens or more, and the projector is used.

A ninth invention is characterized in that, in the eighth invention, the LED chip has a substantially square shape in a top view and a maximum rated current of 300 mA or more.
A tenth aspect of the invention is characterized in that, in the ninth aspect of the invention, the reflector block is made of an integrally molded resin material, and a reflective layer made of a metal material is formed on the inner peripheral surface of the micro reflector. To do.
According to an eleventh aspect, in the ninth aspect, a metal is integrally formed on a core material of the reflector block, a resin is integrally formed on an outer peripheral portion, and a reflective layer made of a metal material is formed on an inner peripheral surface of the micro reflector. It is characterized by.
In a twelfth aspect of the invention according to any one of the eighth to eleventh aspects, the micro-reflector includes an upper opening, a bottom opening in which the LED chip is disposed in the vicinity, and a reflecting surface, and the reflecting surface includes: A first inner peripheral surface that is located on the bottom opening side and acts to collect the irradiation light from the LED chip toward the central axis, and a central axis that is located on the upper opening side than the first inner peripheral surface A second inner peripheral surface having a narrow angle with respect to the second inner peripheral surface, and a third inner peripheral surface located on the upper opening side of the second inner peripheral surface and having a narrow angle with respect to the central axis, To do.
In a thirteenth aspect based on the twelfth aspect, the cross-sectional shape of each inner peripheral surface is linear.
A fourteenth aspect of the invention is a red light LED light source device, a red light transmissive liquid crystal panel that modulates light emitted from the red light LED light source device, a green light LED light source device, and the green light light source device. A transmissive liquid crystal panel for green light that modulates light emitted from the LED light source device, an LED light source device for blue light, and a transmissive liquid crystal panel for red light that modulates light emitted from the LED light source device for red light A dichroic prism that combines red light, green light, and blue light, and a projection optical system that projects combined light from the dichroic prism, the red light LED light source device and the green light LED A light source device and the LED light source device for blue light are constituted by the LED light source device according to any one of the second to thirteenth inventions. It is.
According to a fifteenth aspect, in the twelfth aspect, the total light flux value of the red light LED light source device, the green light LED light source device, and the blue light LED light source device is 2000 lumens or more. To do.
A sixteenth aspect of the invention is characterized in that, in the fourteenth or fifteenth aspect of the invention, an irradiation surface formed by the micro reflector is configured to be slightly larger than each of the liquid crystal panels.
A seventeenth invention is characterized in that, in the first to seventh inventions, the plurality of LED chips emit ultraviolet light.
An eighteenth aspect of the invention is a UV ink curing device having a light source formed by connecting a plurality of LED light source devices according to the seventeenth aspect of the invention.
A nineteenth aspect of the invention is a UV sterilization apparatus having a light source formed by connecting a plurality of LED light source devices according to the seventeenth aspect of the invention.
A twentieth invention is characterized in that, in the first to seventh inventions, the plurality of LED chips emit infrared light.
A twenty-first invention is a reflector block used in the LED light source device of the first to thirteenth inventions.

According to the present invention, an LED light source device having a light distribution angle of 30 degrees or less, excellent light flux distribution and directivity, and having a total light flux value of 2000 lumens (lm) or more, and a desktop projector including the light source device. It becomes possible to provide.

It is a block diagram of the projector which concerns on 1st embodiment. It is a composition side view of the LED light source device concerning a first embodiment. (A) The top view of the reflector block which concerns on 1st embodiment, (b) The schematic diagram of a micro reflector. It is a schematic diagram which shows the magnitude relationship of a micro reflector and a liquid crystal light valve. It is the top view and side view of a modification of a reflector block. It is a perspective view of an LED light source device provided with the reflector block of FIG. It is a simulation result of the light distribution angle of the reflector block which concerns on 1st embodiment. (A) shows a case without a reflector, (b) shows a case with a reflector (without a lens), and (b) shows a case with a reflector (with a lens). (A1) is the principal part enlarged view of (a), (b1) is the principal part enlarged view of (b). It is a side surface schematic diagram which shows the shape of the micro reflector which concerns on 2nd embodiment. It is a side surface schematic diagram for demonstrating the optical characteristic of the micro reflector which concerns on 2nd embodiment. (A) The top view of the reflector block which concerns on 2nd embodiment, (b) The top view of the LED light source device which concerns on 3rd embodiment. It is a side surface schematic diagram which shows the shape of the micro reflector which concerns on 4th embodiment, (a) is the micro reflector 91a, (b) is the micro reflector 91b, (c) is the micro reflector 91c. It is a side view for demonstrating the internal peripheral surface shape of the micro reflector 91a which concerns on 4th embodiment. (A1) is a schematic side view showing the shape of the microreflector 91a according to the fourth embodiment, (b1) is a schematic side view showing the shape of the microreflector 92 according to Comparative Example 1, and (a2) is the fourth embodiment ( It is the directivity simulation result of the LED light source device which concerns on the micro reflector 91a), (b2) is the directivity simulation result of the LED light source device which concerns on the comparative example 1. FIG. It is a top view of the LED light source device which concerns on 5th embodiment. It is a side surface schematic diagram which shows the shape of the micro reflector which concerns on 5th embodiment. It is a structure side view of the comparative example 2 which is a well-known LED light source device. It is a simulation result of the light distribution angle of a LED light source device, (a) is the LED light source device which concerns on 5th embodiment, (b) is the LED light source device which concerns on the comparative example 2, (c) is LED which concerns on the comparative example 3. The result of a light source device is shown. It is a simulation result of the luminous flux amount and luminous flux distribution of an LED light source device, (a) is the LED light source device which concerns on 5th embodiment, (b) is the LED light source device which concerns on the comparative example 2, (c) is 4th embodiment. The result of the LED light source device which concerns on (micro reflector 91b) is shown. It is a simulation result of the directivity of the LED light source device, (a) is the LED light source device according to the fifth embodiment, (b) is the LED light source device according to comparative example 2, and (c) is the fourth embodiment (micro reflector). The result of the LED light source device concerning 91b) is shown. It is a block diagram of the conventional projector. It is a structure side view of the LED light source device which concerns on 6th embodiment. It is a schematic diagram which shows the cross-section of a wiring layer. It is a structure side view of the LED light source device which concerns on 7th embodiment. (A) Top view and (b) Range of micro reflector in reflector block in which micro reflectors are arranged in a 5 × 5 staggered pattern. (A) Top view and (b) Range of micro reflector in reflector block in which micro reflectors are arranged in a 7 × 6 zigzag pattern. It is a structure side view of the LED light source device which concerns on 8th embodiment. It is a top view of the mounting board concerning a 9th embodiment. It is a top view of the module board concerning a ninth embodiment. It is a simulation result of the ultraviolet light distribution of the LED light source device which concerns on 7th embodiment, (a) is the distance of a light-receiving surface 40mm, (b) is the distance of a light-receiving surface 60mm, (c) is the distance of a light-receiving surface 85mm. Results are shown.

Hereinafter, the present invention will be described based on examples.
<< first embodiment >>
<Configuration>
FIG. 1 is a configuration diagram of a projector 1 according to the first embodiment.
The LED light source device of the present embodiment includes three LED light source devices 21, three collimator lenses 22, three liquid crystal light valves 23, a dichroic prism 31, and a projection optical system 32.

The LED light source device 21, the collimator lens 22, and the liquid crystal light valve 23 are for emitting R (red), G (green), and B (blue) light to the dichroic prism 31.
Red light (R light) from the LED light source device 21R is collimated by the collimator lens 22R and light-modulated by the liquid crystal light valve 23R. The liquid crystal light valve 23R is a transmissive liquid crystal panel (HTPS liquid crystal panel) arranged in a matrix, and is a known light modulator that modulates R light for each pixel in accordance with a video signal. The same applies to the green light (G light) from the LED light source device 21G and the blue light (B light) from the LED light source device 21B, which are collimated by the

collimator lenses

22G and 22B, and are made known by the known liquid crystal light valves 23G and 23B. Light modulated.

The dichroic prism 31 has two dichroic films arranged so as to be orthogonal to each other, and one dichroic film 14 reflects R light, but transmits G light and B light other than R light, The dichroic film 14 reflects B light, but transmits R light and G light other than B light. The projection optical system 32 includes a plurality of projection lenses on which the light synthesized by the dichroic prism 31 is incident and a projection lens housing that accommodates the plurality of projection lenses. The projection optical system 32 emits the projection light L and displays a color image on the screen. Enlarge and project.

The configuration of the LED light source device 21 will be described in detail with reference to FIG. FIG. 2 is a schematic diagram for explaining the structure, and does not accurately show the arrangement of the LED chips 46 in the present embodiment.
The LED light source device 21 includes a mounting substrate 41, an inorganic white insulating layer 42 applied on the upper surface of the mounting substrate 41, a wiring layer 43 applied and formed on the upper surface of the inorganic white insulating layer 42, an insulating layer 44, The mounting part 45, the LED chip 46, the translucent resin layer 47, and the reflector block 50 are provided.

The mounting substrate 41 is a plate material made of a metal having a surface excellent in thermal conductivity and electrical characteristics. For example, a heat-spreader having a water-cooled structure having a surface made of copper (a laminated structure made of three types of copper plates, an upper plate, a middle plate, and a lower plate) Body) and a copper plate (for example, 0.5 to 1.00 mm thick). A material having a low thermal conductivity such as a glass epoxy resin cannot be employed because a doughening phenomenon in which the amount of light at the light emission center portion, in particular, the heat dissipation becomes poor, occurs.

On the surface of the mounting substrate 41, an inorganic white insulating layer 42 that also serves as a reflective material is provided. The inorganic white insulating layer 42 preferably has an average reflectance of 70% or more and more preferably 80% or more in the visible light wavelength region. The inorganic white insulating layer 42 is an ink in which white inorganic powder (white inorganic pigment) and silicon dioxide (SiO ₂ ) are main components and these are mixed with a solvent of diethylene glycol monobutyl ether containing organic phosphoric acid (hereinafter referred to as “white”). It may be formed by applying and firing (for example, heating at 160 to 250 ° C.).

The thickness of the inorganic white insulating layer 42 is preferably thin from the viewpoint of heat dissipation characteristics, but a certain thickness is required from the viewpoint of withstand voltage and tear strength. Depending on the blending ratio of white inorganic powder and silicon dioxide, the withstand voltage of the insulating film required for LED mounting is generally 1.5 to 5 kV, and the white inorganic insulator is about 1 KV / 10 μm. The thickness is preferably 15 μm or more. On the other hand, in order to prevent the heat dissipation performance from being deteriorated by the inorganic white insulating layer 42, it is preferable that the inorganic white insulating layer 42 has a certain thickness or less. That is, the thickness of the inorganic white insulating layer 42 is set in the range of 10 to 80 μm, for example, and preferably in the range of 25 to 50 μm.

As the white inorganic pigment, for example, titanium oxide (TiO ₂ ), zinc oxide, alumina, or a combination thereof is used. The content of the white inorganic pigment in the formed white insulating layer is appropriately adjusted depending on the required reflectance, but is preferably 40 to 70% by weight, more preferably 50 to 65% by weight. This is because if it is 40% by weight or more, a sufficient reflection effect can be obtained, and if it is 70% by weight or less, the fluidity of the ink necessary for forming a uniform film can be secured.

The white inorganic powder preferably has an average particle size of 100 μm or less, and more preferably has an average particle size of 50 μm or less. The white inorganic powder having such a particle size is suitable for application by screen printing, ink jet method, dispenser method or spray coating method.
At this time, in order to improve the heat dissipation performance of the white insulating layer, the above-described liquid material (white inorganic ink) is a highly thermally conductive filler made of an inorganic material (for example, silicon carbide (SiC) coated with an nm-size alumina film). May be mixed.

A white inorganic ink made of such an insulating material is applied onto a metal plate and heated at, for example, 160 to 250 ° C., so that nano-sized insulating particles dispersed in the solvent are arranged following the unevenness of the substrate surface. At the same time, the solvent evaporates to form a dense white insulating layer (film). In other words, the nano-sized ceramic mixed powder is heated under atmospheric pressure while in direct contact with the metal surface, sintered in situ, and the metal surface is bonded at the bonding interface using the diffusion state due to the nano-size effect. At least a part of the system white insulating layer forms a laminated structure with the metal layer.

For example, the inorganic white insulating layer 42 is superior in thermal conductivity by about an order of magnitude compared to glass epoxy, and therefore has a high heat dissipation performance. Compared to a PLCC (Plastic-leaded-chip-carrier) having the same configuration, the heat dissipation performance is 2 to 5 times higher. Is estimated to have Furthermore, the sulfidation phenomenon can be suppressed by covering the metal surface on the substrate with the inorganic white insulating layer 42.

A wiring layer 43 is drawn and formed at a necessary position on the inorganic white insulating layer 42. The wiring layer 43 is formed by drawing and applying a conductive metal ink (for example, silver ink or a hybrid ink in which silver and copper are mixed) by screen printing, an ink jet method, a dispenser method, or the like, and then baking and metallizing. . The wiring layer 43 may be drawn after the primer treatment.

The insulating layer 44 may have the same composition as that of the inorganic white insulating layer 42, or may be selected from organic resins (for example, polyimide resins, olefin resins, polyester resins, and mixtures or modified products thereof). 1 or more types of resins). The thickness of the insulating layer 44 is determined from the balance between insulating properties and thermal conductivity, and is, for example, 10 to 60 μm, preferably 10 to 30 μm.

Examples of the polyimide resin include polyimide having an imide ring structure, polyamideimide, and polyesterimide. Examples of the olefin resin include polyethylene, polypropylene, polyisobutylene, polybutadiene, polyisoprene, cycloolefin resin, and copolymers of these resins. Examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and liquid crystal polyester.

The mounting portion 45 is made of the same material as the wiring material or a member having excellent thermal conductivity. For example, the mounting portion 45 may be formed by applying and baking a metal paste material such as a copper paste, a silver paste, or a solder paste. good. The mounting portion 45 may not be provided, and the upper surface of the inorganic white insulating layer 42 or the mounting substrate 41 may be exposed.

The LED chip 46 emits light from, for example, gallium nitride (GaN, AlGaN, InGaN), gallium phosphide (GaP, GaAsP), gallium arsenide (GaAs, AlGaAs, AlGaInP), or zinc oxide (ZnO). It is a surface mount type LED bare chip selected according to the above. A large number of LED chips 3 are arranged in a matrix in n rows × m columns (for example, 6 series × 7 parallels, 4 series × 4 parallels) in the reflector block, and so-called COB (Chip On Board) mounting. In order to achieve high brightness, the LED chip 46 uses, for example, an LED chip having a maximum rated current of 300 mA or more, preferably a maximum rated current of 400 mA or more, and more preferably a maximum rated current of 500 mA or more. The size of the LED chip 46 is 3 to 4 mm square or less (preferably 1.5 mm square or less), and all have the same specifications in units of emission colors. In the first embodiment, an LED chip having 1.0 × 1.0 × 0.15 mm and a light distribution angle of 150 degrees was used.

Table 1 below shows an arrangement example of LED chips for realizing 3000 lm, 4000 lm, and 5000 lm. The external size in Table 1 refers to the size of the mounting substrate on which the LED chip is mounted (or the mounting area on which the LED chip is mounted).
[Table 1]

The translucent resin layer 47 is a transparent resin layer made of, for example, an epoxy resin or a silicone resin. In order to emit desired R light, G light, and B light, red, green, and / or blue light is used. A phosphor may be mixed.
A convex lens (microlens) formed of a transparent resin (for example, an epoxy resin or a silicone resin) on the upper surface of the translucent resin layer 47 and having a spherical surface (side-view arcuate shape) for focusing light emitted from the LED chip 46. It may be provided. By providing this convex lens, it is possible to easily realize the light distribution angle within a target value (for example, 10 to 30 degrees).

The configuration of the reflector block 50 will be described in detail with reference to FIG.
The reflector block 50 includes 20 micro reflectors 51 and a reflective layer (reflective surface) 52 formed on the inner peripheral surface of the micro reflector 51. The plate-like reflector block 50 is integrally formed. In the first embodiment, the plate-like reflector block 50 is manufactured by injection molding an organic resin. As long as a highly accurate surface can be formed, the manufacture of the reflector block 50 is not limited to injection molding, and the reflector block 50 may be manufactured by cutting resin or metal. Although it is difficult at the technical level at the time of filing, it will be possible to produce it with a 3D printer in the future.
The reflector block 50 may have a structure in which a metal (for example, 42 alloy or copper) is used as a core material, an outer peripheral portion is covered with an organic resin, and a surface is subjected to a reflective material treatment.

As shown in FIG. 3A, the 20 micro reflectors 51 are arranged in 5 rows × 4 columns at a pitch of 3 mm in the vertical direction and a pitch of 3 mm in the horizontal direction. The micro-reflector 51 is a frustoconical space expanded from the bottom toward the upper end (outgoing side) (see FIG. 3B), and has a bottom diameter of 2 mm, an upper end diameter of 3.05 mm, and a high height. It has a thickness of 4 mm and an expansion angle of 7.5 °, and has a linearly inclined reflective layer (inner peripheral surface) 52. A reflective layer 52 is formed on the inner peripheral surface of the micro reflector 51 by electrolytic polishing of aluminum or aluminum vapor deposition.
The bottom of the micro-reflector 51 for the projector has a LED chip side ratio of 1.5 to 3 times (preferably 1.5 to 2 times) and a diameter of 3 mm or less, and the height is 2 to 10 LED chip side ratio. The upper end portion has a diameter of 3 to 6 times (preferably 4 to 5 times) in terms of the LED chip side ratio. The arrangement pitch of the micro reflectors 51 is preferably 6 mm or less in both vertical and horizontal directions, and more preferably 5 mm or less. From another aspect, LED chip, so that it can position the LED chips with one or more density per 12.25mm ² (preferably one or more density per 9 mm ^2), determines the arrangement pitch of the micro reflectors 51 . However, in order to obtain a desired light flux distribution, it is preferable that the micro reflectors 51 are provided so as not to overlap each other (have an independent upper opening).

In the center of the bottom of each micro reflector 51, an LED chip 46 is arranged. LED chips 46 arranged on five micro reflectors 51 arranged on four straight lines extending vertically in FIG. 3 are connected in series, and the five LED chip groups connected in series are connected in parallel. (5 series x 4 parallel). The light distribution angle formed by the 20 LED chips 46 arranged in a matrix is preferably 30 degrees or less, more preferably 5 to 20 degrees or 10 to 15 degrees.
FIG. 3 illustrates an example in which 20 micro reflectors 51 are provided. However, the number of micro reflectors 51 is not limited to this, and for example, 8 to 100 (preferably 12 to 100, more). Preferably, it may be 16-50.
As shown in FIG. 4, the reflector block 50 is slightly larger than the liquid crystal light valve 23 (for example, the area ratio is 1.21 times or more, preferably 1.44 times or more, more preferably 1.69 times or more). It is preferable to make it the magnitude | size which comprises an irradiation surface. From another viewpoint, the liquid crystal light valve 23 is completely surrounded by each micro reflector 51 constituting the outer edge of the irradiation surface (the liquid crystal light valve 23 does not overlap each micro reflector 51 located on the outermost side). It is preferable to constitute the surface. This is because, with such a configuration, irradiation light with high output and excellent uniformity can be incident on the dichroic prism 31. In order to configure such an irradiation surface in a compact manner, it is preferable to arrange the micro reflectors 51 in a staggered manner or in a honeycomb manner as in a modification described later.

<Modification>
FIGS. 5A and 5B are a plan view and a side view of a modified example of the reflector 25 having 42 micro reflectors 51. FIG. The reflector block 50 includes a pair of left and right outer frame portions 53, and three partition frames 54 provided in the upper part of the figure and two in the lower part of the figure. The reflective layer 52 by electrolytic polishing of aluminum or aluminum deposition is provided on the inner peripheral surface of the micro reflector 51 as in FIG.
The outer dimensions of the reflector block 50 of FIG. 5 are 24 mm × 24 mm, and the LED chips 46 are arranged with a pitch of 2.6 mm in the left-right direction and a pitch of 3.0 mm in the up-down direction. , Are arranged alternately. In the reflector block 50 of FIG. 5, the micro reflectors 51 are arranged in a staggered manner or a honeycomb so that the pitch between the centers of the micro reflectors is narrowed to increase the degree of integration. That is, the centers of the upper openings of the three micro reflectors 51 that are in contact with each other are arranged so as to form the apex of an equilateral triangle. The top view shape of the micro-reflector 51 is not limited to the illustrated circular shape, and may be, for example, a regular polygon of a hexagon or more. In this case, the bottom opening and the top opening are preferably similar and concentric.
FIG. 6 shows a perspective view of the LED light source device 21 including the reflector block 50 of FIG. The inorganic white layer 42 is exposed at the micro reflector 51 of the reflex letter 50, the cutout portion surrounded by the partition frame, and the outer portion of the outer frame portion 53.

Three LED light source devices 21 having the same specifications are provided as described above, and are used as light sources for emitting red light (R light), green light (G light), and blue light (B light). .

<Simulation>
<A. Maximum illuminance and received light bundle>
In order to verify the performance of the reflector block 50 of the first embodiment, a simulation was performed under the following conditions. The reflector block 50A used here is a micro reflector 51 having the same shape as that shown in FIG. 3B (that is, a bottom diameter of 2 mm, an upper end diameter of 3.05 mm, a height of 4 mm, and an expansion angle of 7.5 °). It has a model without lens.
(1) As shown in FIG. 3A, 20 LED chips were arranged in 5 rows × 4 columns at a pitch of 3 mm in the vertical direction and a pitch of 3 mm in the horizontal direction. Note that no microlens is placed.
(2) Assuming 10,000 light beams per LED chip, 20 LED chips result in 200,000 light beams.
(3) Assuming a luminous flux of 1 lumen per LED chip, the total luminous flux of 20 LED chips is 20 lumens.
(4) The following detector is set as the light receiving surface.
100mm ahead 25mm square detector (200 x 200 divisions)

When the difference between the maximum illuminance and the received light bundle was verified between the case where the reflector block 50 was arranged and the case where it was not arranged, the results shown in Table 2 below were obtained.
[Table 2]

From the simulation results (Table 2), it can be seen that when the reflector block 50 having the linearly inclined reflecting layer 52 shown in FIG. 6 is arranged, the luminous flux is improved by 4.82 times compared to the case without the reflector.

<B. Light distribution angle>
FIG. 7 is a diagram illustrating an example of a light distribution angle simulation analysis result different from Table 2.
7A shows a case where there is no reflector, FIG. 7B shows a case where a reflector block 50A (without a lens) is used, and FIG. 7C shows a case where a reflector block 50B (with a lens) is used. (A1) is the principal part enlarged view of (a), (b1) is the principal part enlarged view of (b). FRED (Photo Engineering LLC) was used as the analysis software.
As a result of the analysis, when the light receiving area is 25 mm square and the distance is 100 mm, the illuminance is 524,922 (lx) and the spread angle is 75 ° at (a), and the illuminance is 1,552,104 (lx) and the spread angle is (b). 30 ° (10 ° for the condensing part (the dark part of the line)), and in (c) the illuminance is 2,734,062 (lx) and the divergence angle is 30 ° (the condensing part is compared to (b)) It was even darker).

<< Second and Third Embodiment >>
FIG. 8 is a schematic side view showing the shape of the micro reflector 61 of the second embodiment. The micro reflector 61 includes a bottom opening 62 in which the LED chip 46 is disposed at the center, a small diameter body 63, a reflecting surface (64, 65, 66, 67), and an upper opening 68. The diameter of the bottom opening 62 is 1.8 mm, the diameter of the top opening 68 is 4.0 mm, and the distance (height) from the bottom opening 62 to the top opening 68 is 5.0 mm. The cylindrical small-diameter cylinder 63 has a bottom end 62 that constitutes a bottom opening 62 and an upper end that is continuous with a reflective surface (first inner peripheral surface 64).

The reflecting surface is composed of first to fourth inner peripheral surfaces (64, 65, 66, 67) and has a structure in which the diameter is increased upward while the angle with respect to the central axis is gradually reduced. . That is, the first inner peripheral surface 64 has an enlarged diameter of 60 °, the second inner peripheral surface 65 has a 65 °, the third inner peripheral surface 66 has a 70 °, and the fourth inner peripheral surface 67 has a 85 ° diameter. The angle with respect to the central axis is gradually reduced from 62 toward the upper opening 68. The first to fourth inner peripheral surfaces (64, 65, 66, 67) all act so as to collect the irradiation light from the LED chip 46 toward the central axis side of the micro reflector 61. Unlike the present embodiment, the reflecting surface may be constituted by three or five inner peripheral surfaces having different angles, and in this case as well, the angle with respect to the central axis is narrowed stepwise in a range of 60 ° to 85 °, for example. However, the diameter is increased upward.

FIG. 9 shows the reflector effect when the light is emitted from the left end (a), the center (b), and the right end (c) of the LED chip. As can be seen from FIG. 9B, the emitted light from the center of the LED chip is reflected by the inner peripheral surface of the reflector 61, and most of the light becomes parallel light.

FIG. 10A is a plan view of the reflector block 60 according to the second embodiment.
The rectangular reflector block 60 includes 20 reflectors 61 arranged in 4 series and 5 parallel in 4 mm pitches in the vertical and horizontal directions. The structure of the reflector block 60 is the same as that of the first embodiment.

FIG. 10B is a plan view of the LED light source device 70 according to the third embodiment.
The circular reflector block 71 includes 16 reflectors 72 arranged in 4 series and 4 parallel at 4 mm pitches in the vertical and horizontal directions. The structure of the reflector block 71 is the same as in the first and second embodiments. The LED light source device 70 includes an external reflector 73 having a height of 30 mm. The external reflector 73 has a reflecting structure on the inner peripheral surface surrounding the reflector block 71 and has a shape that is expanded in diameter upward.

In order to verify the performance of the reflector block 60 according to the second embodiment, a light source unit in which 20 LED chips are arranged in each opening of the reflector block 60 and a light source unit in which the reflector block 60 is removed from the light source unit are simulated. Carried out. In addition, a simulation was performed for the LED light source device 70 according to the third embodiment including the external reflector 73. These simulations were performed under the condition that the 25 mm square detector 80 is disposed at a distance of 30 mm. The simulation results are shown in Table 3.

[Table 3]

From the results in Table 3, when the reflector is not present, the luminous flux on the light receiving surface is only 13.4%, but when the reflector is present (inside), it is improved to 70.5% (5.26 times). I understand.
Thus, with the reflector block of the second embodiment, it was confirmed that the light collecting effect was obtained 5 times or more without using a lens. Moreover, according to LED light source device 70 which concerns on 3rd embodiment provided with the external reflector 73, it has confirmed that the condensing effect was acquired further.

<< 4th embodiment >>
FIG. 11 is a schematic side view showing the shapes of the micro reflectors 91a to 91c of the fourth embodiment. The micro reflectors 91a to 91c of the fourth embodiment are the same as those of the first to third embodiments, and 20 reflectors are arranged in an array on the reflector block (see FIG. 10A).

In order to verify the performance of the micro reflectors 91a to 91c, a simulation was performed on the light source unit in which the micro reflectors 91a to 91c are arranged and the light source unit in which the micro reflectors 91a to 91c are removed from the light source unit. These simulations were performed under the condition that a 25 mm square detector was placed at a distance of 30 mm. Table 4 shows the specifications of the light source unit that is a premise of the simulation, and Table 5 shows the results of the simulation.

In the fourth embodiment, the output of the LED chip is set to 1 lm for convenience, but an LED chip having an equivalent size of 250 to 2600 lm is commercially available. By mounting this LED chip, three light sources are provided. Can be set to 2000 lm or 3000 lm or more.

[Table 4]

[Table 5]

From the results in Table 5, it was confirmed that a luminous flux (lm) of 5 times or more can be obtained with and without the reflector.
FIG. 12 is a side view for explaining the inner peripheral surface shape of the micro reflector 91a according to the fourth embodiment. A portion indicated by a point in the figure is a bending point, and a portion (inner peripheral surface) sandwiched between two points is linear. In other words, the micro reflector 91a has a reflective surface composed of seven inner peripheral surfaces having different angles.
As described above, the reflection layer is constituted by a large number of inner peripheral surfaces having a linear cross section, so that it is possible to secure a constant area at the central portion where the light density is highest. In other words, in the light source for projectors, it is not preferable to increase the light density only in the central part (that is, the area of the part having a high light density becomes too small). In this regard, when the reflector reflection layer is formed of a smooth peripheral surface (smooth curved surface), the area of the portion having a high light density tends to be too small.

FIG. 13 (a1) is a schematic side view showing the shape of the micro reflector 91a according to the fourth embodiment, (b1) is a schematic side view showing the shape of the micro reflector 92 according to Comparative Example 1, and (a2) is the fourth embodiment. It is the directivity simulation result of the LED light source device which concerns on a form (micro reflector 91a), (b2) is the directivity simulation result of the LED light source device which concerns on the comparative example 1. FIG.
In the micro-reflector 91a having a large number of inner peripheral surfaces with linear cross sections at different angles, as shown in (a2), the tip of the directivity data is crushed, so that a certain area can be secured for a portion with a high light density. I understand.
In Comparative Example 1 having a smooth curved reflecting surface, the tip of the directivity data is pointed as shown in (b2), and it is easy to concentrate on the center of light. I find it difficult to do.
From the above, it can be said that the micro-reflector having a large number of inner peripheral surfaces with straight sections having different angles is superior in terms of the uniform distribution of light rays as compared with the reflector having a reflecting surface having a smooth curved surface.
In addition, about the micro reflector 91b, the light quantity, light beam distribution, and directivity simulation are implemented, and this result is mentioned later by the location of 5th embodiment.

<< 5th embodiment >>
In the fifth embodiment, an LED light source device 100 including one LED chip and one reflector is disclosed.
FIG. 14 is a plan view of the LED light source device 100 according to the fifth embodiment. The LED light source device 100 of this embodiment includes a reflector block 101, a reflector 102, and an LED chip 103.
The basic structure of the rectangular reflector block 101 is the same as that of the first to third embodiments, except that one reflector 102 is provided at the center. The LED chip 103 has a size of 3.0 × 3.0 × 0.45 mm, an output of 20 lm, and an orientation angle of 150 degrees.
In the fifth embodiment, as in the fourth embodiment, the output is set to 20 lm for convenience, but the total luminous flux value from the three light sources is set to 2000 lm or 3000 lm or more by changing the LED chip to a high output one. It is possible.

FIG. 15 is a schematic side view showing the shape of the reflector 102. Each dimension of the reflector 102 is three times the corresponding dimension of the micro reflector 91b according to the fourth embodiment. The inner peripheral surface of the reflector 102 is subjected to the same reflective material treatment as in the first to third embodiments.

In order to verify the performance of the LED light source device 100 according to the fifth embodiment, light rays and light fluxes were analyzed by simulation. In this simulation, the 25 mm square detector 80 was implemented on the condition that it is arranged at a distance of 30 mm.
When simulating the performance of the fifth embodiment, the simulation for the following comparative example was also performed at the same time.

[Comparative Example 2]
Comparative Example 2 is a known LED light source device 110 including two

condenser lenses

111 and 112 as shown in FIG. The LED light source device 110 includes condensing

lenses

111 and 112 and a mounting substrate 114 on which an LED chip 113 is mounted.
The condensing lens 111 is a biconvex lens, a convex lens 111a on the opposite side (liquid crystal light valve side) to the

LED chip

113, 111c on the LED chip 113 side, and a disk-shaped body 111b sandwiched between 111a and 111c. It consists of. The convex lens 111a has a diameter of 27 mm, a thickness of 7.5 mm, and a curvature of 0.0555. The trunk 111b has a diameter of 27 mm and a height of 2.5 mm. The convex lens 111c has a diameter of 27 mm, a thickness of 0.5 mm, and a curvature of 0.188. The transmittance of the condenser lens 111 is 90%.

The condensing lens 112 is a plano-convex lens, and includes a convex lens 112a on the opposite side (liquid crystal light valve side) to the LED chip 113 and a body portion 112b on the LED chip 113 side. The convex lens 112a has a diameter of 16 mm, a thickness of 5 mm, and a curvature of 0.1. The cylindrical portion 112b has a diameter of 16 mm and a height of 4.2 mm. The transmittance of the condenser lens 112 is 90%.
An LED chip 113 of 3.5 mm × 2.8 m square is disposed below the center of the condenser lens 112. The LED chip 113 is electrically connected to a wiring pattern provided on the mounting substrate 114.

[Comparative Example 3]
The comparative example 3 is the light source device which removed the reflector block 101 from the LED light source device 100 of 5th embodiment (refer FIG.17 (c)). In other words, since the LED chip of Comparative Example 3 is the same as that of the fifth embodiment, the output is the same (20 lm). However, since the reflector block 101 is not provided, the LED chip is different in terms of the spread angle and restraint.

[simulation result]
Hereinafter, the result of the simulation about each LED light source device is shown. In FIG. 17, the fifth embodiment, comparative example 2, and comparative example 3 are compared, and in FIG. 18, the fifth embodiment, comparative example 2 and fourth embodiment (micro reflector 91b) are compared. For comparison by simulation, the total luminous flux of each LED light source device was set to 20 lm.

<Photo alignment>
In FIG. 17, the result of the simulation of the orientation angle performed about each LED light source device of 5th embodiment, the comparative example 2, and the comparative example 3 is shown. 17, (a) shows the LED light source device 100 according to the fifth embodiment, (b) shows the LED light source device 110 according to Comparative Example 2, and (c) shows the result of the LED light source device according to Comparative Example 3. Yes. In the figure, the number of light rays is reduced to 100 in order to make the light rays easier to see.
From FIG. 17A, it can be seen that the orientation angle of the irradiation light of the LED light source device 100 according to the fifth embodiment is small, and the light density at the center is the highest in the figure.
From FIG. 17B, the orientation angle of the irradiation light of the LED light source device 110 according to Comparative Example 2 is smaller than that in FIG. 17C, and the light density is uniformly distributed as compared with FIG. I understand that.
From FIG. 17 (c), it can be seen that in Comparative Example 3 that does not include a reflector, light rays are randomly spread.

<Light flux amount and light flux distribution>
The amount of light beam reaching the 25 mm square detector 80 is (a) 19.17 lm in the fifth embodiment, (b) 7.76 lm in the comparative example 2, and (c) 15 in the fourth embodiment (micro reflector 91b). .26 lm.
In FIG. 18, the result of the simulation of the light beam quantity and light beam distribution which were performed about each LED light source device of 5th embodiment, the comparative example 2, and 4th embodiment (micro reflector 91b) is shown. 18, (a) is the LED light source device 100 according to the fifth embodiment, (b) is the LED light source device 110 according to the comparative example 2, and (c) is the LED light source according to the fourth embodiment (micro reflector 91b). The result of the apparatus is shown.
From FIG. 18A, the LED light source device 100 according to the fifth embodiment has the highest light density at the center (brightest), but from another point of view, the luminous flux is at the center of the 25 mm square detector 80. Collectively, it can be seen that the periphery of the 25 mm square detector 80 becomes dark and uneven brightness occurs.
From FIG. 18B, the LED light source device 110 according to the comparative example 2 has a wide orientation angle of the irradiated light, and the light beam density is distributed over a wide area compared to FIGS. 18A and 18C. I understand.
From FIG.18 (c), although the LED light source device which concerns on 4th embodiment (micro reflector 91b) is inferior in the point of the light density of center part compared with Fig.18 (a), it is excellent in the point of the uniform distribution of a light ray. I understand that. In particular, it is superior to the fifth embodiment and the comparative example 2 in that a constant area is ensured in the central portion having the highest light density.
In FIG. 19, the result of the directivity simulation performed about each LED light source device of 5th embodiment, the comparative example 2, and 4th embodiment (micro reflector 91b) is shown. 19 (a) and 19 (c), it can be seen that the tip is flat and the uniformity is good.

As described above, it was found from the simulation results that the LED light source device 100 according to the fifth embodiment has a feature that the orientation angle is small and the light density is high. As a result of comparison with the fifth embodiment, it was confirmed that the LED light source device according to the fourth embodiment (microreflector 91b) has the highest evaluation as the light source for the projector.

<< 6th embodiment >>
The LED light source device 121 of the sixth embodiment is different from the LED light source device 21 of the first embodiment in that the wiring layer 143 is mainly composed of two layers and the inorganic white insulating layer 144 is provided. Below, it demonstrates centering around difference and omits description about a common structure.
The configuration of the LED light source device 121 will be described in detail with reference to FIG. FIG. 21 is a schematic diagram for explaining the structure, and does not accurately show the arrangement of the LED chips 146 in the present embodiment.
The LED light source device 121 includes a mounting substrate 141, an inorganic white insulating layer 142 applied to the upper surface of the mounting substrate 141, a wiring layer 143 applied and formed on the upper surface of the inorganic white insulating layer 142, and an inorganic white insulating material. The layer 144, the wiring exposed part 145, the LED chip 146, the translucent resin layer 147, and the reflector block 150 are provided.

The mounting substrate 141 is the same as the mounting substrate 41 of the first embodiment.
The inorganic white insulating layer 142 has the same composition as that of the first embodiment except for the white inorganic pigment, but titanium oxide (TiO ₂ ) is used for the white inorganic pigment in order to improve the reflection efficiency.

As illustrated in FIG. 22, the wiring layer 143 includes a first wiring layer 1431 formed on the mounting substrate side and a second wiring layer 1432 formed on the first wiring layer 1431.
The first wiring layer 1431 is a wiring layer made of a material having good adhesion to the inorganic white insulating layer 142 (for example, a conductive resin composition). More specifically, the first wiring layer 1431 is formed with a wiring pattern on the inorganic white insulating layer 142 by, for example, printing a gold paste or a metal paste containing metal particles that function as a conductive filler and a binder resin. And is formed by heating. As the metal particles contained in the metal paste, materials used in ordinary printed circuits and conductive films are used, but the most common is silver (Ag) particles. The metal particles may be mixed with nano-sized metal particles and micron-sized metal particles, and the resistance value may be lowered by filling the spaces between the micron-sized metal particles with the nano-sized particles. As the binder resin contained in this metal paste, for example, a dicyclopentadiene type epoxy resin is disclosed. The binder resin constituting the first wiring layer 1431 is immersed in the porous inorganic white insulating layer 142 and hardened, thereby providing an anchor effect.

The second wiring layer 1432 is a wiring layer made of a material having a resistance lower than that of the first wiring layer 1431. For example, a silver paste containing nano-sized silver particles is printed on the first wiring layer 1431 by printing or the like. It is formed by providing a wiring pattern and heating. The second wiring layer 1432 may be formed of a plurality of layers.

The inorganic white insulating layer 144 is formed on the wiring layer 143 and functions as a reflective layer that reflects light emitted from the LED chip 146. The inorganic white insulating layer 144 is formed by applying and baking a white inorganic ink using titanium oxide (TiO ₂ ) as a white inorganic pigment on the second wiring layer 1432, similarly to the inorganic white insulating layer 142. The The inorganic white insulating layer 144 that also functions as a solder resist layer is applied so as to expose the wiring exposed portion 145. The wiring exposed portion 145 is a mount portion of the LED chip 146 and a wire bond region.

The LED chip 146 is the same LED bare chip as in the first embodiment, but is different in that it has a structure in which one electrode is provided on the back surface. As in the first embodiment, each LED chip 146 is arranged so as to be within the range of each micro reflector 151. However, since there is only one wire bonding area, the first embodiment has two wire bonding areas. As compared with the above, the bottom opening (and the top opening) of the micro reflector 151 can be made smaller in diameter. That is, in the sixth embodiment, it is possible to increase the degree of integration of the LED chips 146 compared to the first embodiment. In addition, the aspect which raises the integration degree of an LED chip more by flip-chip joining both electrodes is later mentioned by 8th embodiment.

The translucent resin layer 147 is the same as in the first embodiment, and is a resin layer that is transparent or mixed with a phosphor.

According to the LED light source device 121 of the sixth embodiment described above, it is possible to increase the degree of integration of the LED chips 146 compared to the first embodiment and to make the bottom opening and the top opening of the micro reflector 151 smaller. It is. When the degree of integration of the LED chip 146 is increased, the heat dissipation of the insulating layer becomes a problem. However, as described in the first embodiment, the inorganic white insulating layer 142 can be formed thin, so that it becomes a donut shape. The problem of the phenomenon does not occur. In order to improve the heat dissipation performance of the inorganic white insulating layer 142, the above-described liquid material (white inorganic ink) is coated with a high thermal conductive filler made of an inorganic material (for example, silicon carbide (SiC) with an nm-size alumina film. May be mixed.

Further, according to the LED light source device 121 of the sixth embodiment, the two-layer wiring structure of the wiring layer 143 improves the adhesion with the porous inorganic white insulating layer 144, and the high temperature due to the heat generation of the LED chip 146. It is possible to ensure durability over a long period even in an environment. Furthermore, since the inorganic white insulating layer 144 is also provided on the wiring layer 143, the reflectance of light emitted from the LED chip 146 is increased, and the amount of light can be increased.

<< Seventh Embodiment >>
The LED light source device 221 of the seventh embodiment is different from the LED light source device 121 of the sixth embodiment in that the reflector block 250 is disposed on the translucent resin layer 247. Below, it demonstrates centering around difference and omits description about a common structure.
The configuration of the LED light source device 221 will be described in detail with reference to FIG. FIG. 23 is a schematic diagram for explaining the structure, and does not accurately show the arrangement of the LED chips 246 in the present embodiment.
The LED light source device 221 includes a mounting substrate 241, an inorganic white insulating layer 242 applied on the upper surface of the mounting substrate 241, a wiring layer 243 applied and formed on the upper surface of the inorganic white insulating layer 242, and an inorganic white insulating material. A layer 244, an LED chip 246, a translucent resin layer 247, a dam material 248, and a reflector block 250 are provided.

The mounting substrate 241 is the same as the mounting substrate 141 of the sixth embodiment.
The inorganic white insulating layer 242 is the same as the inorganic white insulating layer 142 of the sixth embodiment, and the inorganic white insulating layer 244 is the same as the inorganic white insulating layer 144 of the sixth embodiment.

The wiring layer 243 includes a first wiring layer formed on the mounting substrate side and a second wiring layer formed on the first wiring layer, as in the sixth embodiment.

The LED chip 246 is an LED bare chip similar to that of the sixth embodiment, but has a structure in which one electrode is provided on the back surface. Since there is one wire bonding region, the bottom opening (and top opening) of the micro reflector 151 can be made smaller in diameter than in the first embodiment where there are two wire bonding regions.

The dam material 248 is formed so as to surround the outer periphery of the mounting region of the LED chip 246 and is made of, for example, a white filler-containing resin. The surface of the dam material 248 is given light reflectivity and reflects light emitted from the LED chip 246.

The reflector block 250 is arranged so that the center of the bottom opening of the micro reflector 251 is directly above the center of the LED chip 246. In FIG. 23, the reflector block 250 is disposed so as to cover the dam material 248 and the translucent resin layer 247, but the reflector block 250 may be disposed on the translucent resin layer 247. Good.

In the seventh embodiment, since the micro reflector 251 is disposed above the translucent resin layer 247, the degree of freedom of wiring of the LED chip 246 is high, and the degree of integration of the LED chip 246 can be increased. In other words, since the wire bonding area can be set within the range of a circle having the pitch diameter of the micro reflector 251 (hereinafter sometimes referred to as “routable area”), the degree of integration of the LED chips 246 can be increased.

¡The larger the gap between the upper openings of the micro-reflector 251, the larger the diameter of the wireable area. In the example of FIG. 23, the routable area is a range of two vertical lines A-A ′ passing through the center of the micro reflector wall 251a.

24A and 25A are configuration examples of the micro block 250. FIG.
In the micro block 250 of FIG. 24A, 25 micro reflectors 251 are provided in a staggered pattern with a pitch of 3.5 mm in the vertical direction and 3.05 mm in the horizontal direction. × 26 × t4.8 mm.
In the micro block 250 of FIG. 25A, 42 micro reflectors 251 are provided in a staggered pattern of 7 × 6 at a pitch of 3.5 mm in the vertical direction and 3.05 mm in the horizontal direction. × 26 × t4.8 mm.
Each micro-reflector 251 is the same in both FIG. 24A and FIG. 25A and has a bottom opening of a circle having a diameter of 1.48 mm and a top opening of a circle having a diameter of 3.1 mm.

In the case of 250 of the micro block in FIG. 24A, the sum of each routable area is a hatched area in FIG. 24B, which is wider than the sum of the upper opening of the micro reflector 251. The same applies to the micro block 250 in FIG. Thus, when the micro reflectors of the same shape are arranged at an equal pitch, each routable area is a circle of the same size that circumscribes each other.

The electrical connection between the LED chip 246 and the wiring layer 243 can be performed by a wire bond connection within the routable area. Here, if the wire exceeds the range of the upper opening of the micro-reflector and is electrically connected below the micro-reflector wall, the wire may block light from the adjacent LED chip 246. It is preferable to carry out within the range of the upper opening of the micro reflector. In other words, the LED chip 246 and the wiring layer 243 are preferably connected within the range of the upper opening of the micro reflector 251 in which the LED chip 246 is disposed, and the bottom of the micro reflector 251 in which the LED chip 246 is disposed. It is more preferable that the connection is made within the range of the opening. In the example of FIG. 23, the range of the two vertical lines B-B ′ is within the range of the bottom opening of the micro reflector 251.

According to the LED light source device 221 of the seventh embodiment, since the reflector block 250 is attached after forming the translucent resin layer 247, the manufacture becomes easy. Further, since the routable area is wide, the micro reflector 251 can be miniaturized and densified, and the reflector block 250 can be miniaturized.

<< Eighth Embodiment >>
The LED light source device 321 of the eighth embodiment is different from the LED light source device 121 of the sixth embodiment in that the LED chip 346 is flip-chip bonded to the wiring layer 343. Below, it demonstrates centering around difference and omits description about a common structure.
The configuration of the LED light source device 321 will be described in detail with reference to FIG. FIG. 26 is a schematic diagram for explaining the structure, and does not accurately show the arrangement of the LED chips 346 in the present embodiment.

The LED chip 346 and the wiring layer 343 are flip-chip bonded, for example, with bumps 349 mainly composed of gold or silver, or are connected using an anisotropic conductive film (common name: ACF). Thereby, since an area for wire bonding is not required, the LED chips 346 can be mounted with high density. The flip chip bonding is performed by, for example, forming bumps 349 on the LED chip 346 by plating or the like, mounting the wiring layer 343, and then thermocompression bonding the LED chip 346 from the back surface 346B side.

Since the upper surface of the LED chip 346 is a light emitting surface, an underfill material such as an epoxy material may be used around the bump 349 in order to reinforce the bump 349 used for flip chip bonding. In the case of using the above-described ACF, the ACF itself plays the role of an underfill material, so that underfill is unnecessary.

According to the LED light source device 321 of the eighth embodiment, since the area for wire bonding is not required, the micro reflector 351 can be downsized and densified, and the reflector block 350 can be downsized. It becomes possible.

<< Ninth Embodiment >>
The LED light source device of the ninth embodiment relates to an LED light source device that emits ultraviolet light for UV curing type ink curing and UV sterilization. The LED light source device of the ninth embodiment is configured by arranging a plurality of COBs in a row.
In the LED light source device of the ninth embodiment, an LED chip, a reflector block, or the like is mounted on the mounting substrate 441 shown in FIG. 27 to form one unit light source 421, and 10 unit light sources are mounted on the module substrate 460 as shown in FIG. 421a to j are arranged side by side. In FIG. 28, the LED chips and reflector blocks mounted on the ten unit light sources 421a to 421j are omitted, and only the mounting substrate and the module substrate 460 are shown.

The unit light source 421 used in the LED light source device of the ninth embodiment has the same configuration as the LED light source device 121 of the sixth embodiment except for the white inorganic pigment and the transparent resin layer used for the LED chip and the inorganic white insulating layer. I am doing. Below, it demonstrates centering around difference and omits description about a common structure.

The configuration of the unit light source 421 of the ninth embodiment will be described in detail. The configuration of the unit light source 421 is the same as that shown in FIG. 26, and includes a mounting substrate 441, an inorganic white insulating layer applied to the upper surface of the mounting substrate 441, a wiring layer applied and formed on the upper surface of the inorganic white insulating layer, An inorganic white insulating layer formed on the wiring layer, an LED chip, and a reflector block are provided. Although an adhesive frame for sealing a dam material or quartz glass is not shown, a white inorganic pigment of alumina used as a reflective material may be used as these materials. In the ninth embodiment, unlike the sixth embodiment, the transparent resin layer may not be provided. However, in order to protect the chip, it is preferable that the entire module is collectively covered with quartz glass or the like. The size of the unit light source is 50 × 30 mm, and the size when ten long sides of the unit light sources 421a to 421j are arranged adjacent to each other on the module substrate 460 is 50 × 300 mm.

The mounting substrate 441 is the same as the mounting substrate 141 of the sixth embodiment.
The composition of the inorganic white insulating layer is the same as that of the first embodiment except for the white inorganic pigment, but alumina is used as the white inorganic pigment because of its high reflectance with respect to ultraviolet rays.
Similar to the wiring layer 143 of the sixth embodiment, the wiring layer includes a first wiring layer formed on the mounting substrate side and a second wiring layer formed on the first wiring layer.
The inorganic white insulating layer on the wiring layer is applied to a region excluding the power supply electrode 4431 and the wiring exposed portions 4432 and 4433 shown in FIG. 27. As in the sixth embodiment, the wiring layer insulation and the LED chip It functions as a reflective layer that reflects light emission.
The power electrode 4431 is connected to an external power supply device and supplies power to the unit light source.
An LED chip is mounted on the wiring exposed portion 4432. Similarly to the sixth embodiment, the LED chip and the wiring layer can be electrically connected by providing an electrode on the back surface (wiring layer side) of the LED chip and performing flip chip bonding.
The wiring opening 4433 is a portion where the wiring layer is wire-bonded to the LED chip.

The LED chip is a type of LED bare chip that uses wire bonding and backside wiring, as in the sixth embodiment, and is, for example, a gallium nitride-based LED chip that has a light emission wavelength in the UV region. As the detailed emission wavelength region, a UV-A region is disclosed for UV-curable ink curing, and a UV-C region is disclosed for UV sterilization. As specific wavelengths, for example, a wavelength of 365 nm for UV curable ink curing and a wavelength of 260 nm for UV sterilization are disclosed. The output angle of the LED chip is, for example, an orientation of 150 ° Lambertian.

100 LED chips are mounted on one unit light source 421. 100 LED chips are mounted in a 10 × 10 staggered arrangement at a pitch of 3.8 mm in length and 3 mm in width at the position of the wiring opening 4432 shown in FIG. The size of the LED chip is 1.05 × 1.05 × 0.11 mm. In the case of a UV light source, the pitch is preferably 5 mm in length and 5 mm in width or less, more preferably 4.25 mm in length and 3.7 mm in width or less in order to achieve a desired ultraviolet intensity. From the viewpoint of ultraviolet intensity, the narrower the pitch, the better. However, the optimum pitch is finally determined in a range satisfying the vertical and horizontal pitches of 5 mm or less in terms of the trade-off with the ease of manufacturing the reflector block.
Since the LED light source device of the ninth embodiment is composed of 10 unit light sources 421a to 421j, the total number of LED chips used is 1000.

The reflector block has the same configuration as the reflector block 150 of the sixth embodiment, and the arrangement of the micro reflectors is an extension of the 5 × 5 zigzag arrangement in FIG. 24A to a 10 × 10 zigzag arrangement. It has become. As for the size of the micro reflector, the top opening is φ3.9 mm, the bottom opening is φ1.5 mm, and the height is 3.7 mm.

The translucent resin layer is not normally provided on the reflector block, but when encapsulating with the translucent resin layer, a phosphor suitable for the wavelength in the UV region is appropriately selected.

In order to verify the performance of the LED light source device of the ninth embodiment, a simulation was performed to determine the ultraviolet light distribution on the light receiving surface in the presence or absence of the reflector block.
The number of rays to be analyzed was 100,000 per LED chip (100 million in total), and the size of the light receiving surface was 250 × 500 mm.

Incidentally, there is a need for the LED light source device as ultraviolet irradiation to maintain the ultraviolet intensity even when the distance from the light receiving surface is long, for the following reasons.
(1) When a printing paper that is a target for curing UV curable ink is large, it is likely to bend, and it is necessary to irradiate the light receiving surface apart.
(2) As a UV sterilization application, it is necessary to irradiate the light receiving surface away from the object in order to provide versatility.
Therefore, a simulation was carried out under the condition that the distance of the light receiving surface was changed between 40 mm and 85 mm, and the ultraviolet intensity was verified.

FIG. 29 shows the result of the simulation of the ultraviolet intensity distribution when the distance of the light receiving surface is (a) 40 mm, (b) 60 mm, and (c) 85 mm. In each of the tables (a), (b), and (c), the middle row shows the result of the model (in the table, described as “no reflector”) obtained by removing the reflector block from the LED light source device of the ninth embodiment. Column shows the result of the model of the LED light source device of the ninth embodiment (described as “with reflector” in the table). The items of the results are the UV intensity distribution on the light receiving surface (in the table, described as “surface distribution”), the UV intensity plot along the center line of the light receiving surface (in the table, indicated as “cross section”), the entire light receiving surface Illuminance (denoted as “illuminance” in the table).

As can be seen from the “surface distribution” and “cross section” rows in (a), when the reflector block is present, the ultraviolet light is concentrated at the center of the light receiving surface and the ultraviolet light distribution is narrower and the peak than when there is no reflector block. It can be seen that is doubled.
The tendency that the ultraviolet rays are concentrated at the center of the light receiving surface and the distribution of the ultraviolet rays is narrower in the cases (b) and (c) than in the case without the reflector block.
The ratio of the peak when there is a reflector block to when there is no reflector block was about 2.2 times for (b) and about 2.5 times for (c).

From the simulation results of (a) to (c), it is confirmed that when there is a reflector block, the UV distribution is narrower and the peak intensity is 2 to 2.5 times higher than when there is no reflector block. It was done. In addition, it was confirmed that as the distance of the light receiving surface becomes longer, the ratio of the peak intensity when there is a reflector block to when there is no reflector block increases.

According to the LED light source device of the ninth embodiment, since the reflector block is used, the ultraviolet intensity can be maintained even if the distance between the light source and the light receiving surface is large, and UV curing or UV used away from the light source is used. It can be said that it is suitable for sterilization applications.

Although some embodiments have been described in detail in the present disclosure by way of example only, many modifications may be made to the embodiments without substantially departing from the novel teachings and advantages of the present invention. Is possible.

The LED light source device of the present invention is suitable for infrared illumination (for example, for infrared cameras), UV printing / UV curing / UV exposure light sources, and headlamps that want to use output effectively far. Especially effective in applications such as infrared illumination and UV curing (effect work such as ultraviolet curable sheets) that want to give more output to a distant object (see the ninth embodiment for these module configurations) ).
Furthermore, when this module is applied with infrared illumination, it is possible to achieve high output and miniaturization (handy), which could not be realized until now. Can also be used for in-vehicle mounting.

21: LED light source device, 22: collimator lens, 23: liquid crystal light valve, 31: dichroic prism, 32: projection optical system, 41: mounting substrate, 42: inorganic white insulating layer (substrate reflection layer)
43: wiring layer, 44: insulating layer, 45: mounting portion, 46: LED chip, 47: translucent resin layer, 48: microlens, 50: reflector block, 51: microreflector, 52: reflection layer (reflection) Surface), 53: outer frame portion, 54: partition frame, 60: reflector block, 61: micro reflector, 62: bottom opening, 63: small diameter body portion, 64: first inner peripheral surface, 65: second inner peripheral surface , 66: third inner peripheral surface, 67: fourth inner peripheral surface, 68: upper opening, 71: LED light source device, 72: reflector block, 73: micro reflector, 74: external reflector, 80: 25 mm square detector, 91: Micro reflector (fourth embodiment), 92: Micro reflector (Comparative example 1), 100: Reflector, 110: Known LED light source device, 111: Light condensing lens 111a: convex lens, 111b: barrel, 111c: convex lens, 112: condenser lens, 112a: convex lens, 112b: barrel, 113: LED chip, 114: mounting board, 121: LED light source device, 141: mounting board, 142: Inorganic white insulating layer (substrate reflection layer), 143: wiring layer, 1431: first wiring layer, 1432: second wiring layer, 144: insulating layer, 146: LED chip, 147: translucent resin 150, reflector block, 151: micro reflector, 221: LED light source device, 241: mounting substrate, 242: inorganic white insulating layer (substrate reflecting layer), 243: wiring layer, 244: insulating layer, 246: LED chip 247: Translucent resin layer, 248: Dam material, 250: Reflector block, 251: Micro reflector, 251a: Ichroreflector wall, 321: LED light source device, 341: mounting substrate, 342: inorganic white insulating layer (substrate reflecting layer), 343: wiring layer, 344: insulating layer, 346: LED chip, 346A: front surface, 346B: back surface 347: Translucent resin layer, 349: Bump, 350: Reflector block, 351: Micro reflector, 441: Mounting substrate, 421: Unit light source, 421a to j: Unit light source, 460: Module substrate, L: Projection light

Claims

A mounting board having a metal surface at least,
A first insulating layer formed on the surface of the mounting substrate;
A wiring layer formed as an upper layer of the first insulating layer;
In an LED light source device comprising a large number of LED chips having the same specifications and surface-mounted in a matrix on a mounting substrate,
Comprising a reflector block having the same number of micro-reflectors as the LED chip;
The micro-reflector has a bottom opening and a top opening having a larger diameter than the bottom opening;
The wiring layer is formed by applying a metal paste containing a resin and a metal powder that penetrates and hardens into the insulating layer and is heated, and a first conductive layer formed on an upper surface of the first conductive layer. An LED light source device comprising: a second conductive layer having a resistance lower than that of one conductive layer.
The LED light source device according to claim 1, wherein a second insulating layer functioning as a reflective layer as an upper layer of the wiring layer is formed so as to leave an exposed portion exposing the wiring layer.
The first insulating layer is composed of a porous inorganic white insulating layer formed by applying a liquid material containing nanoparticulated SiO 2 and a white inorganic pigment and heating at 160 to 250 ° C. The LED light source device according to claim 2.
The second insulating layer is composed of a porous inorganic white insulating layer formed by applying a liquid material containing nanoparticulated SiO 2 and a white inorganic pigment and heating at 160 to 250 ° C. The LED light source device according to claim 3.
5. The microreflector according to claim 2, wherein the top opening of the micro reflector is enlarged in diameter by 70 to 85 ° with respect to the bottom opening, and the distance between the bottom opening and the top opening is 4 to 8 mm. LED light source device according to the above.
The micro-reflectors are arranged in a staggered manner, the distance between the centers of the micro-reflectors is smaller than the diameter of the upper openings, and the upper openings do not overlap each other. LED light source device.
The LED light source device according to claim 6, wherein the LED chip is connected to the wiring layer through the opening within a pitch upper opening of the micro reflector on which the LED chip is disposed. .
The LED light source device according to any one of claims 2 to 7, wherein the LED light source device has a light distribution angle of 30 degrees or less, a total luminous flux value of 500 lumens or more, and a projector.
The LED light source device according to claim 8, wherein the shape of the LED chip viewed from above is substantially square and has a maximum rated current of 300 mA or more.
The reflector block is made of an integrally molded resin material,
The LED light source device according to claim 9, wherein a reflective layer made of a metal material is formed on an inner peripheral surface of the micro reflector.
The LED light source according to claim 9, wherein a metal is integrally formed on the core of the reflector block, a resin is integrally formed on an outer peripheral portion, and a reflective layer made of a metal material is formed on an inner peripheral surface of the micro reflector. apparatus.
The micro reflector includes a top opening, a bottom opening in which the LED chip is disposed in the vicinity, and a reflective surface,
The reflective surface is located on the bottom opening side, and operates on the upper opening side of the first inner peripheral surface and the first inner peripheral surface acting to collect the irradiation light from the LED chip on the central axis side. And a second inner peripheral surface having a narrow angle with respect to the central axis, and a third inner peripheral surface positioned closer to the upper opening than the second inner peripheral surface and having a narrow angle with respect to the central axis. The LED light source device according to claim 8, wherein the LED light source device is an LED light source device.
13. The LED light source device according to claim 12, wherein a cross-sectional shape of each inner peripheral surface is a linear shape.
A red light LED light source device, a red light transmissive liquid crystal panel that modulates light emitted from the red light LED light source device, and
An LED light source device for green light, a transmissive liquid crystal panel for green light that modulates light emitted from the LED light source device for green light,
A blue light LED light source device, a red light transmissive liquid crystal panel that modulates light emitted from the red light LED light source device, and
A dichroic prism that combines red, green and blue light;
In a projector comprising a projection optical system that projects combined light from a dichroic prism,
The projector according to claim 2, wherein the LED light source device for red light, the LED light source device for green light, and the LED light source device for blue light are constituted by the LED light source device according to claim 2.
13. The projector according to claim 12, wherein a total light flux value of the LED light source device for red light, the LED light source device for green light, and the LED light source device for blue light is 2000 lumens or more.
The projector according to claim 14 or 15, wherein an irradiation surface formed by the micro reflector is configured to be slightly larger than each of the liquid crystal panels.
The LED light source device according to claim 1, wherein the plurality of LED chips emit ultraviolet light.
A UV ink curing device having a light source comprising a plurality of LED light source devices according to claim 17 connected in series.
An apparatus for UV sterilization having a light source comprising a plurality of LED light source devices according to claim 17 connected in series.
The LED light source device according to any one of claims 1 to 7, wherein the plurality of LED chips emit infrared light.
The reflector block used for the LED light source device in any one of Claims 1 thru | or 13.