JP2016091994A - Light-emitting device and distribution light variable head lamp system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive substrate attaining downsizing and highly accurate wiring design enabling individual flashing with a simple structure, a light-emitting device, and a distribution light variable head lamp system.SOLUTION: A drive substrate 10 includes: a substrate 13 having a first main surface 13a; a plurality of first wirings 11 formed on the first main surface 13a, and extending in a first direction; and a plurality of second wirings 12 formed on the first main surface 13a, arranged along a second direction crossing the first wirings 11 so as to respectively separate from the first wirings 11. A light-emitting device includes the drive substrate 10, and a plurality of light-emitting elements 14 installed on the drive substrate 10. A distribution light variable head lamp system includes the light-emitting device.SELECTED DRAWING: Figure 1A

Description

  The present disclosure relates to a light emitting device and a light distribution variable headlamp system.

In recent years, a light-emitting device using a light-emitting element such as a light-emitting diode (LED) can obtain high luminance by mounting a plurality of light-emitting elements on an insulating substrate on which matrix wiring is formed. It is used as a light source for mounting on vehicles.
However, normally, when forming a matrix wiring on a substrate, it is necessary to make a multilayer wiring especially when trying to realize individual blinking of a plurality of light emitting elements, so that the configuration becomes complicated and the manufacturing process is complicated. And increase in manufacturing cost. Further, the substrate size increases, which hinders downsizing of the light emitting device.

2. Description of the Related Art Conventionally, multilayer wiring or inner layer wiring boards that have been fired by sandwiching or pasting a thin film wiring pattern on a green sheet of ceramics such as aluminum oxide (for example, Patent Document 1) . However, light sources that require high-density mounting in order to achieve high brightness, for example, light sources mounted on vehicles, require ultra-miniaturization such as the width and pitch of wiring patterns, resulting in shrinkage due to ceramic firing. The resulting reduction in dimensional accuracy of the wiring pattern makes wiring design as a matrix substrate difficult.
In addition, various matrix wirings have been proposed in the light emitting device (for example, Patent Document 2), and the light emitting device design corresponding to the wiring pattern of the wiring substrate is required in order to sufficiently ensure the performance of each light emitting element. Is required.

JP 2009-135535 A JP 2009-302542 A

  The present disclosure has been made in view of the above problems, and provides a light-emitting device and a light distribution variable headlamp system that can be individually flashed while sufficiently reducing the size of the light-emitting element with a simple structure. For the purpose.

The present disclosure includes the following embodiments.
(1) a substrate having a first main surface;
A plurality of first wirings formed on the first main surface and extending in a first direction;
A plurality of second wirings formed on the first main surface, extending in the second direction, and being divided and disposed;
A plurality of light emitting devices including a first electrode and a second electrode disposed on the same surface side of the semiconductor multilayer structure;
The first electrode is connected to face the first wiring,
The second electrode includes a first connection portion and a second connection portion connected to the first connection portion, and faces the second wiring, and is divided into at least two second portions separated in the second direction. It is connected to the first connection part and the second connection part across the wiring,
The light emitting device, wherein the plurality of light emitting elements are arranged along the second direction.
(2) the light emitting device described above;
An in-vehicle camera that recognizes the position of the vehicle ahead,
A light distribution variable headlamp system comprising an area to be shielded and an electronic control device for determining a light distribution pattern.

According to the present disclosure, it is possible to provide a light-emitting device that can be individually flashed while being miniaturized by a simple structure and sufficiently exhibiting the performance of the light-emitting element.
Furthermore, by using such a light emitting device, a high-performance variable light distribution headlamp system can be provided.

It is a schematic plan view which shows an example of the drive board | substrate in embodiment of the light-emitting device of this indication. 1B is a schematic plan view of the drive substrate of FIG. 1A on which a light emitting element is mounted. FIG. FIG. 1B is a schematic plan view of a light emitting device showing a layout of electrodes of the light emitting device mounted on the drive substrate of FIG. 1A. FIG. 1B is a schematic plan view of a light emitting device showing a layout of another electrode of the light emitting device mounted on the drive substrate of FIG. 1A. It is AA 'line sectional drawing of FIG. 1D. It is BB 'line sectional drawing of FIG. 1D. It is a figure which shows the matrix circuit by the drive board | substrate which mounts a light emitting element. FIG. 2 is a schematic cross-sectional manufacturing process diagram of the light emitting device of the present disclosure (a cut along line AA ′ in FIG. 1A). It is a schematic cross-sectional manufacturing process drawing of the light-emitting device which concerns on embodiment of this indication. It is a schematic cross-sectional manufacturing process drawing of the light-emitting device which concerns on embodiment of this indication. It is a schematic plan view of the light-emitting device of FIG. 2C. It is a schematic plan view showing an example of a drive board concerning an embodiment of this indication. 3B is a schematic plan view of the drive substrate of FIG. 3A on which a light emitting element is mounted. FIG. It is a schematic plan view showing an example of a drive board concerning an embodiment of this indication. FIG. 4B is a schematic plan view of the drive substrate of FIG. 4A on which a light emitting element is mounted. FIG. 4B is a schematic plan view of the light emitting device showing a layout of electrodes of the light emitting device mounted on the drive substrate of FIG. 4A. It is a schematic plan view showing an example of a drive board concerning an embodiment of this indication. FIG. 5B is a schematic plan view of the drive substrate of FIG. 5A on which a light emitting element is mounted. It is a block diagram which shows the electric constitution of the light distribution variable headlamp system which concerns on embodiment of this indication. It is a flowchart which shows the control flow of the light distribution variable headlamp system which concerns on embodiment of this indication.

  In the present application, the size and positional relationship of members shown in each drawing may be exaggerated for clarity of explanation. In the following description, the same name and reference numeral indicate the same or similar members, and detailed description thereof will be omitted as appropriate.

<Light emitting device>
The light emitting device includes a substrate having a first main surface, a plurality of first wirings formed on the first main surface and extending in the first direction, and formed on the first main surface, extending in the second direction, and divided. And a plurality of light emitting elements each including a first electrode and a second electrode mounted on the driving substrate and disposed on the same surface side of the semiconductor multilayer structure. With.

[Drive board]
(substrate)
The substrate includes a first main surface. Moreover, it is preferable to also have a 2nd main surface as a main surface on the opposite side to a 1st main surface. The first main surface and / or the second main surface is preferably flat. As the shape of the substrate, for example, a rectangular flat plate shape is preferable.
The thickness and size of the substrate are not particularly limited and can be appropriately adjusted depending on the size and number of light emitting elements to be mounted. For example, the thickness of the substrate is about 0.05 mm to 10 mm, preferably about 0.1 mm to 1 mm. The size is about 50 mm × 50 mm to 100 mm × 100 mm.

  The substrate is not particularly limited as long as it is formed of an insulating material, for example, ceramic substrate such as alumina, aluminum nitride, glass substrate, glass epoxy substrate, paper phenol substrate, paper epoxy substrate, Examples thereof include a glass composite substrate, a low-temperature co-fired ceramics (LTCC) substrate, a resin substrate formed using a thermoplastic resin, a thermosetting resin, and the like. Among these, a ceramic substrate is preferable, and a substrate made of aluminum nitride is more preferable from the viewpoint of heat dissipation. Moreover, it is preferable that heat conductivity is 170 W / m * K or more.

  The substrate is preferably a single layer structure, particularly a single layer structure ceramic substrate. However, in the manufacturing process, two or more layers may be laminated and finally integrated to constitute the substrate.

  When a ceramic substrate is used as a substrate, a co-firing (co-firing) method may be used, but in order to obtain a substrate with high dimensional accuracy, so-called post firing (sequential firing) is used. Method) is preferred. The post-fire method is a method of forming a wiring on a previously fired ceramic plate. When the wiring is formed by the post-fire method, a fine pattern can be formed by a photolithography technique by a vacuum evaporation method using a mask pattern using a mask pattern, a sputtering method, plating, or the like.

(First wiring and second wiring)
The first wiring and the second wiring are formed on the first main surface of the substrate.
The first wiring and the second wiring are, for example, for electrically connecting the light emitting element and an external power source and applying a voltage from the external power source to the light emitting element. As will be described later, the first wiring is connected to the first electrode of the light emitting element, and the second wiring is connected to the second electrode of the light emitting element. The first wiring and the second wiring may correspond to either the anode or the cathode, but it is preferable that the first wiring corresponds to the cathode and the second wiring corresponds to the anode.

  On the first main surface, a plurality of first wirings are arranged in the first direction and are independently arranged. Here, the first direction may be any direction, but may be a direction (for example, a row direction) corresponding to a two-dimensional x-axis, for example. Further, the extension in the first direction is not only a linear extension (for example, 11 in FIG. 1A, 21 in FIG. 3A), but also a stepped shape (41 in FIG. 5A), a curved shape, or a combination of these. Moreover, the form extended toward a 1st direction is also included. As long as one first wiring extends in the first direction, it may be partially branched such as 2-branch and 3-branch (31 in FIG. 4A), or may have a partially branched portion. Also good. The branched first wirings are preferably adjacent to each other and extended substantially in parallel.

  The second wiring extends and is divided in the second direction on the first main surface (for example, 22x, 22x in FIG. 3A), and a plurality of such second wirings are arranged independently. (For example, 22x, 22y, and 22z in FIG. 3A, 32x, 32y32z in FIG. 4A, and 42x, 42y, and 42z in FIG. 5A). Here, the second direction may be any direction as long as it intersects the first wiring extending in the first direction. The angle of intersection is not particularly limited, but is preferably a perpendicular direction (for example, a direction corresponding to the y-axis, a column direction). However, orthogonal here means that a variation of about ± 10 ° is allowed. In addition, being arranged along the second direction is not only arranged on a straight line, but also when a stepped line, a curved line, and a line having a combination thereof extend in the second direction, these The form arrange | positioned on a line is also included.

“Multiple” means that a plurality of second wirings are arranged so as to form a pair with a plurality of first wirings. In addition, when the second wiring extends along the second direction, the first wiring usually intersects with the first wiring at one or more sites. However, at the site corresponding to these intersections, Are arranged apart from the first wiring without crossing each other. In other words, since the second wiring is divided and arranged at a portion corresponding to the crossing portion with the first wiring, one second wiring paired with one first wiring has a plurality of second wirings. It also means that it is arranged by divided pieces. As long as one second wiring is arranged along the second direction, it is adjacent to each other and arranged in parallel so as to correspond to a branch such as two branches (12 in FIG. 1A) and three branches. Also good. Moreover, you may have the site | part branched partially.
It is preferable that the outer periphery of the first wiring and the second wiring is regularly arranged in a matrix direction that forms, for example, a square, a rectangle, a rhombus, or the like.

The first wiring and the second wiring can be formed of a conductive material. For example, a metal such as Au (gold), Ag (silver), Cu (copper), W (tungsten), or Ni (nickel). Alternatively, a single-layer film or a laminated film of an alloy can be used. The thicknesses of the first wiring and the second wiring are not particularly limited, and all may have the same thickness or may have partially different thicknesses. The total thickness of the first wiring and the second wiring is, for example, about 1 μm to 100 μm.
In the case where the first wiring and / or the second wiring are formed of a laminated film, the first wiring and / or the second wiring may have a partially different laminated structure in the plane or in the thickness direction. Good. For example, the surface of the first wiring and / or the second wiring may be partially removed with a laser, and the exposed surface of the first wiring and / or the second wiring may be an oxide. More specifically, when the first wiring or the second wiring is formed by a laminated structure of TiW / Cu / Ni / Au, only Au may be removed and the exposed Ni surface may be an oxide.

The width and interval of the first wiring and the second wiring can be appropriately adjusted depending on the size, number, density, luminance, and the like of the light emitting elements mounted on the drive substrate to be obtained. For example, the width of the first wiring is preferably 1/5 or more and less than 1/2 of the length of one side of the light emitting element. When two or more first wirings are arranged with respect to one light emitting element, the total width of the first wirings only needs to be about this level. The width of the second wiring is preferably larger than 1/5 of the length of one side of the light emitting element and not more than about 1/2. When two or more second wirings are arranged with respect to one light emitting element, the total width of the second wirings may be about this level. In particular, the second wiring is preferably wider than the first wiring. Here, the term “wide” means, for example, the length of the second wiring in the first direction (M in FIG. 1A), and the total width of each branch when the second wiring is branched (N1 + N2 in FIG. 1A). However, both mean that it is wider than the length of the first wiring in the second direction (Q in FIG. 1A). Further, when the first wiring branches, it means that the width of the second wiring (M in FIG. 4A) is wider than the total length in the second direction in each branch (P1 + P2 + P3 in FIG. 4A). To do.
Thus, by making the second wiring wider than the first wiring, the heat generated in the light emitting layer during light emission can be effectively released by the wider second wiring. That is, in the light emitting element to be described later, a region where the second conductive layer connected via the second electrode exists is a region where the light emitting layer exists and generates heat during light emission. Therefore, when this heat is released in the order of the second conductive layer, the second electrode, and the second wiring, if the second wiring is wide, the heat can be effectively dissipated.

  The first wiring and the second wiring are arranged apart from each other on the first main surface of the substrate. In other words, it is preferable that they are not three-dimensionally arranged and are formed of the same layer. Therefore, it is preferable that both of them are formed of a layer made of the same metal material, that is, a single layer or a laminate of the same metal or alloy. For example, it is preferable that they are simultaneously formed by a metal layer having the same composition using a mask pattern.

  On the first main surface of the substrate, there are provided wiring for drawing out the first wiring and second wiring described above in the direction of the end of the substrate, pad electrodes for connecting with electronic components such as connectors, and the like. Further, it may be included. Such routing wiring or the like enables connection with an external power source through electronic components such as connectors mounted on the substrate, for example. The pad electrode is preferably formed wider than the routing wiring.

  In the drive substrate having such a configuration, the matrix wiring can be formed in a single layer structure on a single layer substrate. Therefore, a plurality of light emitting elements can be mounted at high density by freely changing the width, length, interval, and the like of the wiring. In particular, since it is not necessary to form a so-called matrix wiring with a multilayer structure, the thickness or size can be further reduced. In addition, since the process of manufacturing such a driving substrate is very simple, not only can the increase in manufacturing cost be suppressed, but also the contraction of the substrate can be avoided and a highly accurate driving substrate can be obtained. it can. Furthermore, because of the single layer structure, even when the light emitting elements are arranged at a high density, the heat caused by the heat generated by the light emitting elements is quickly released from the front and back surfaces without spreading inside the substrate, and the heat dissipation is further improved. Even better. In addition, since there is no need to form wiring on the back side of the substrate, a metal member such as a heat sink can be brought into close contact with the back side of the substrate. Thereby, the heat dissipation effect can be enhanced.

  In such a drive board, in particular, since the second wiring is divided by the first wiring, the plurality of second wirings are not electrically connected in the state as they are. However, as described later, by mounting the light emitting element so as to straddle the divided second wirings, the divided second wirings can be connected. Therefore, a plurality of electrically conductive second wirings are arranged in pairs with the first wiring. As a result, a driving substrate capable of driving and controlling a plurality of light emitting elements independently of each other can be obtained.

(Light emitting element)
As the light emitting element, a light emitting diode is preferably used.
For example, the light-emitting element is formed on the substrate by using various semiconductors such as a nitride semiconductor such as InN, AlN, GaN, InGaN, AlGaN, and InGaAlN, a group III-V compound semiconductor, a group II-VI compound semiconductor, and the like. A semiconductor laminated structure including a layer, a light emitting layer, and a second conductive layer is formed, and a first electrode and a second electrode are further formed. Examples of the substrate of the light emitting element include an insulating substrate such as sapphire, and a conductive substrate such as SiC, Si, GaN, and GaAs. However, the light-emitting element does not necessarily have these substrates finally, for example, by peeling these substrates after stacking the semiconductor layers.

(First electrode and second electrode)
The first electrode and the second electrode are connected to the first conductive layer and the second conductive layer, respectively. Usually, the first electrode is a light emitting layer and a second conductive layer stacked on the first conductive layer. The second electrode is connected to the second conductive type semiconductor layer, and the first electrode and the second electrode are connected to the same surface side of the stacked structure. Those arranged in the are preferable. More preferably, the first conductive layer is n-type and the second conductive layer is p-type.

  The first electrode and the second electrode are usually disposed inside the light emitting element in plan view. The positions and sizes of the first electrode and the second electrode are not particularly limited, and it is preferable to adjust the positions and sizes so that they can be reliably connected to the first wiring and the second wiring of the driving substrate described above.

  For example, it is preferable that the first electrode is disposed in the central portion of the light emitting element, and the second electrode is disposed so as to surround the first electrode. Since the first wiring connected to the first electrode is disposed between the divided second wirings, the first electrode preferably has a width equal to or narrower than that of the first wiring. A plurality of first electrodes may be arranged on the surface of the second conductive layer.

In general, the second electrode has a full-surface electrode that covers almost the entire upper surface of the second conductive layer in order to uniformly spread the current in the surface to the second conductive layer, and the upper surface is on the first electrode. 2 It has a pad electrode used as a connection part for connecting with wiring. The full-surface electrode is preferably an ohmic electrode that can be electrically connected to the second conductive layer. Since the entire surface electrode is usually formed on the entire upper surface of the semiconductor multilayer structure other than the first electrode formation region, it is preferable to cover the portion other than the portion where the pad electrode is formed with an insulating protective film or the like. The connection part preferably has a plurality of, for example, a first connection part and a second connection part, and may further have one or more connection parts. These connection parts are electrically connected by full-surface electrodes. The width of the first connection portion and the second connection portion of the second electrode is preferably a width corresponding to the second wiring. They may have the same width or different widths.
As described above, since the second electrode is connected to the plurality of second wirings by the connecting portions connected to each other, the divided second wiring can be connected by the second electrode of the light emitting element. Matrix wiring can be realized with a simple pattern, that is, without forming wiring on the substrate as multilayer wiring. In addition, since the divided second wiring can be energized using the second electrode in addition to the semiconductor stacked body in the light emitting element, the conduction resistance can be reduced. Therefore, heat generation when the light emitting element is turned on can be reduced, and the reliability of the light emitting device can be increased.

The second electrode may have a region facing the first wiring when the light emitting element is mounted on the drive substrate. In this case, it is only necessary that the second electrode and the first wiring are arranged with a gap so as not to contact each other. Alternatively, as described above, an insulating protective film may be formed on the surface of the second electrode in the region facing the first wiring or the surface of the first wiring in the region facing the second electrode. This can reliably prevent a short circuit.
Here, the insulating protective film is not particularly limited, and examples thereof include a single layer film or a multilayer film of oxide, nitride, or fluoride such as Si, Al, Nb, Zr, and Ti. . The film thickness can be adjusted as appropriate.

  The first electrode and the second electrode are made of, for example, a metal such as Al, Ag, Au, Pt, Pd, Rh, Ni, W, Mo, Cr, Ti, or an alloy thereof, or an oxide conductive material such as ITO. It can be formed of a layer film or a laminated film. The film thickness may be any film thickness used in this field.

  The full surface electrode also functions as a reflective layer that reflects the light emitted from the light emitting layer toward the light extraction surface. Therefore, it is preferable to form the entire surface electrode with a good reflectance with respect to the wavelength of light emitted from the light emitting layer. Such a full surface electrode is preferably, for example, a single layer film made of Ag having high light reflectivity or an alloy thereof. The full-surface electrode may be a multilayer film with a film made of Ni and / or Ti, etc., in which the film of Ag or an alloy thereof is present in the lowermost layer.

  When using Ag as the full surface electrode, it is preferable to provide a cover electrode that covers the full surface electrode. The cover electrode diffuses the current over the entire surface of the second conductive layer in the same manner as the entire surface electrode. In addition, the cover electrode covers the upper surface and side surfaces of the full surface electrode, shields the full surface electrode, and prevents contact between the full surface electrode and the second electrode. Thus, the cover electrode functions as a barrier layer for preventing migration of the material of the entire surface electrode, particularly Ag. The cover electrode can be formed of, for example, at least one metal selected from the group consisting of Ti, Au, W, Al, Cu, and the like, or an alloy thereof. The cover electrode may be a single layer film or a multilayer film. Specifically, the cover electrode may be a single layer film such as an AlCu alloy or an AlCuSi alloy or a multilayer film including such a film. The full surface electrode and the cover electrode can be formed by sputtering or vapor deposition, respectively.

  Since the surface positions of the semiconductor layers to be connected are different between the first electrode and the second electrode, their surfaces usually have a step. However, by controlling the thicknesses of the first electrode and the second electrode or by disposing a pad electrode, a conductive single layer film or a laminated film on the first electrode and the second electrode, they are substantially the same. It is preferable to form so as to form a surface, that is, the surface is located at the same height. With such a configuration, the mounting of the light emitting device on the drive substrate can be reliably executed without short circuit.

  The light-emitting element may be so-called face-up mounting, which usually joins the insulating substrate side of the light-emitting element to the drive substrate, but is preferably flip-chip mounted. In such mounting, for example, solder such as tin-bismuth, tin-copper, tin-silver, gold-tin, conductive paste such as silver, gold, palladium, bump (print bump, stud bump, It is preferable to use a bonding member selected from brazing materials such as plating bumps, anisotropic conductive materials, and low melting point metals.

  When the light-emitting element is flip-chip mounted, the first electrode and / or the second electrode is preferably connected to the first wiring and / or the second wiring via a stud bump or a solder ball. In particular, the second electrode is preferably connected to the second wiring via the stud bump. Since the second electrode functions as a metal member straddling between the divided second wirings, the second electrode is electrically disconnected from the first wiring, but needs to be connected to the second wiring at at least two points. For this reason, it is preferable that the first wiring arranged so as to divide the second wiring is connected by a member that does not wet and spread and can maintain a constant height. Here, the stud bump means one having a fixed length (height) wire (stud) on a press-bonded ball press-bonded to an electrode, and the stud bump is usually used by a wire bonding apparatus or a bump bonding apparatus. Can be formed. In the light-emitting elements connected in this way, the above-described bonding member is preferably interposed in order to strengthen the bonding between the electrode and the wiring.

The solder ball preferably has a coating part having a melting point lower than the melting point of the core on the core and the outside of the core. What is necessary is just to be able to maintain the shape of the core when performing reflow mounting with solder balls. Specifically, it is preferable to use an alloy having a core mainly composed of Cu and including at least one of Au, Si, Ge, and Sn as the covering portion. Further, it is more preferable to surround the core and have a predetermined base film and an Sn-based film thereon. As the base film, Ni, Ni-B, Ni-P, or the like can be used. Here, the Sn-based coating may be a single-layer coating of Sn-based alloy, or may be a multilayer coating of Sn and other alloy components or Sn alloy. When a multilayer coating of Sn and other alloy components or Sn alloy is used, Sn and other alloy components or Sn alloy are melted in the reflow process for forming the bumps of the Cu core ball on the wiring of the driving substrate. And a uniform alloy layer is formed.
The core component is preferably composed mainly of Cu (that is, the Cu content is 50% by mass or more). In particular, in the case of a ball having a Cu content of 99% by mass or more or a ball of an alloy of Cu and one or more of Zn, Sn, P, Ni, Au, Mo, and W, thermal conductivity and electrical conductivity. It is preferable because it is excellent.

  In order to prevent wetting and spreading of the bonding member, as described above, the surface of the first wiring and / or the second wiring is partially removed with a laser, and the exposed first wiring and / or second wiring is removed. The surface is preferably an oxide. Thereby, also when joining by a pump etc., the stability of the position and / or shape of a joining member is securable.

In the light emitting device according to the present disclosure, the light emitting element is on the first wiring of the drive substrate described above, and at least two (second wiring is branched off) arranged on both sides of the first wiring. If there are two or more, it is mounted on the second wiring. The first electrode is connected to the first electrode, and the second electrode is connected to the second electrode. Two or more light emitting elements are preferably arranged along the second direction, and more preferably two or more light emitting elements are arranged along the first direction and the second direction, respectively. Accordingly, the first wiring and the second wiring are arranged in a row in the second direction by the light emitting element, or in the first direction and the second direction, for example, in a matrix, at a portion corresponding to the intersecting portion. Electrical conduction will occur. Accordingly, each light emitting element can be independently driven and controlled. Therefore, it is possible to select or turn on or off only a desired number of light emitting elements at arbitrary positions. Further, the power level can be controlled only in an arbitrary light emitting element, and brightness can be given in the light emitting device. In particular, as described above, the second electrode of the light emitting element is connected to two or more second wirings that are divided, and thereby the divided second wiring is connected between the semiconductor stacked body and the second electrode. As a result, the conduction resistance can be reduced.
And since it is possible to obtain a light emitting device that can freely control the blinking of such an arbitrary light emitting element, as will be described later, in a light distribution variable headlamp system as a so-called variable light distribution headlamp. It can be used effectively.

(Reflective member)
Each of the plurality of light emitting elements mounted on the driving substrate preferably has a reflecting member formed around the light emitting element. The reflecting member is preferably disposed in contact with the side surface of each light emitting element. The reflecting member is preferably disposed between the substrate and the light emitting element so as to surround the connection portion between the first electrode and the first wiring and the second electrode and the second wiring. The reflecting member may be disposed for each of the light emitting elements or for each of the light emitting elements, but is preferably formed integrally with all the light emitting elements. Thereby, all the light irradiated from the light emitting element can be efficiently extracted from the light extraction surface side (the upper surface or the lower surface of the light emitting element). In addition, the bright / dark boundary between the light emitting region and the non-light emitting region is thereby sharpened, and a so-called light-emitting state can be obtained.

  The reflecting material constituting the reflecting member is preferably a material that can efficiently reflect light emitted from the light emitting element, and more preferably a material that can reflect 80% or more, and more than 90% at its peak wavelength. . Moreover, it is preferable that it is an insulating material.

As the reflective material, is not particularly limited, material capable of reflecting light, for _{example, SiO 2, TiO 2, ZrO} 2, BaSO 4, MgO, it is preferable to use particles such as ZnO. These materials may be used alone or in combination of two or more. Usually, these materials are thermosetting resins, thermoplastic resins, etc., specifically, epoxy resin compositions, silicone resin compositions, modified epoxy resin compositions such as silicone modified epoxy resins; epoxy modified silicone resins, etc. Modified silicone resin composition; hybrid silicone resin; polyimide resin composition, modified polyimide resin composition; polyphthalamide (PPA); polycarbonate resin; polyphenylene sulfide (PPS); liquid crystal polymer (LCP); ABS resin; Resin; used by mixing with resin such as PBT resin.

  For example, the reflective member preferably has a thickness of about 1 μm to 100 μm. In particular, the reflecting member is preferably formed such that the upper surface of the reflecting member does not cover the upper surface of the light emitting element, and is substantially coincident with the upper surface of the light emitting element or disposed above the upper surface of the light emitting element. This can prevent light from the light emitting element from leaking in the lateral direction. In addition, relatively strong light emitted from the side surface of the semiconductor layer including the light emitting layer can be blocked by the reflecting member, and color unevenness can be reduced. Further, in order to increase the reflectance, it is preferable to contain the above-described reflective material in an amount of 40 wt% or more based on the total weight of the reflective member.

(Wavelength conversion layer)
The wavelength conversion layer converts light from the light emitting element into a different wavelength, and is preferably disposed on the light extraction surface side of the light emitting element in the light emitting device. As the wavelength conversion layer, for example, a phosphor or a quantum dot can be used.

Examples of the phosphor that forms the phosphor layer as the wavelength conversion layer include nitride phosphors, oxynitride phosphors, and sialon phosphors mainly activated by lanthanoid elements such as Eu and Ce. Can be mentioned. More specifically, (A) Eu-activated α or β sialon-type phosphor, various alkaline earth metal nitride silicate phosphors, (B) lanthanoid elements such as Eu, transition metal elements such as Mn Alkaline earth metal halogen apatite, alkaline earth halosilicate, alkaline earth metal silicate, alkaline earth metal borate, alkaline earth metal aluminate, alkaline earth metal silicate A rare earth aluminate mainly activated by a phosphor such as alkaline earth metal sulfide, alkaline earth metal thiogallate, alkaline earth metal silicon nitride, germanate, (C) lanthanoid elements such as Ce, Examples thereof include phosphors such as organic or organic complexes that are mainly activated by rare earth silicates or lanthanoid elements such as (D) Eu.
Quantum dots include semiconductor materials such as II-VI, III-V, and I-III-VI semiconductors, specifically ZnS, CdS, CdSe, InAgS ₂ , InCuS ₂ , and core-shell CdS _x. Examples thereof include nano-sized highly dispersed particles such as Se _1-x / ZnS and GaP. It may be InP, InAs, InAsP, InGaP, ZnTe, ZnSeTe, ZnSnP, ZnSnP ₂ .

The phosphor layer is generally disposed on the upper surface of the light emitting element in the same or slightly larger size and shape as the light emitting element before and after mounting the light emitting element on the drive substrate.
The phosphor layer can be formed using a sticking method, an electrodeposition method, an electrostatic coating method, a sputtering method, a vapor deposition method, a potting method, a printing method, a spray method, or the like. The sticking method can be easily formed by sticking a sheet or a plate-like body uniformly including the phosphor layer. In the electrodeposition method, electrostatic coating method, sputtering method, and vapor deposition method, the phosphor layer can be attached to the entire light emitting element and the substrate without using a binder. After the phosphor layer is attached, a resin serving as a binder may be impregnated. In the potting method, the printing method, and the spray method, the phosphor can be selectively attached by using the phosphor dispersed in the translucent member. Here, the translucent member can be formed of a material that can transmit 60% or more, 70% or more, or 80% or more of the peak wavelength of the light emitting element, and includes the above-described thermosetting resin, thermoplastic resin, and the like. It can be selected appropriately.

  The thickness of the phosphor layer can be appropriately adjusted depending on the production method, for example, the deposition conditions and time of the phosphor particles. For example, about 0.01 μm to 100 μm is preferable. The phosphor layer is preferably formed with a substantially uniform thickness.

  As described above, when the reflecting member is formed, it is preferable that the reflecting member covers the side surface of the phosphor layer as well as the side surface of the light emitting element. Thereby, it is possible to reliably extract the light of the lit light emitting element from the light extraction surface regardless of the blinking of the adjacent light emitting elements. It is preferable that all of the side surfaces of the phosphor layer are covered with the reflecting member in the thickness direction and the outer periphery. Thereby, the effect mentioned above can be exhibited more efficiently.

  An electronic component such as a connector may be further mounted on the drive substrate in correspondence with the arrangement of the wiring for routing described above. Moreover, it is preferable that the protective element is mounted.

[Light distribution variable headlamp system]
The variable light distribution headlamp system means that when a vehicle is traveling with a high beam of a headlamp, when a front vehicle such as an oncoming vehicle or a preceding vehicle or a person facing the front appears, This is a headlamp system that detects the position of the light, shields only that position, and irradiates the other position with a high beam. In accordance with the position of the vehicle in front or the person, the area to be blocked out of the headlight irradiation area can be automatically adjusted to avoid giving glare to the driver or person in the vehicle ahead. On the other hand, the driver can always secure a field of view close to that of high beam travel, making it easy to see pedestrians, road signs, distant road shapes, etc., and can contribute to safe driving.

This system includes the above-described light emitting device, an in-vehicle camera that recognizes the position of a vehicle ahead or a person, and an electronic control device that determines an area to be shielded from light and a light distribution pattern. By providing such a configuration, the above-described light emitting device realizes control of shielding or illuminating an arbitrary position by blinking of individual light emitting elements by a correlation action with a vehicle-mounted camera, an electronic control device, or the like. Can serve as a variable light distribution headlamp.
Accordingly, the same control can be performed only by blinking of the light emitting element without using the lens movement, the drive unit for swiveling the lamp (ACT), etc., which are conventionally required in the vehicle headlamp device. Become.

  The light-emitting device normally functions as a pair of light distribution variable headlamps for vehicles disposed on the left and right sides of the vehicle. Each light-emitting device includes a plurality of light-emitting elements as described above. In addition to the light emitting elements, the light emitting device may include a projection lens, a reflecting mirror, a lamp body that accommodates them, and the like.

  The in-vehicle camera captures an image in front of the vehicle and transmits the captured result to the electronic control device.

  The electronic control device is usually composed of a microcomputer including a CPU, RAM, ROM, I / O, and the like. The ROM stores a program for performing light distribution control. The RAM is used as a work area when the CPU performs various calculations.

The electronic control device is connected to the in-vehicle camera, detects the forward vehicle (oncoming vehicle, preceding vehicle, person) and other road objects, lane markings, etc. from the image transmitted from the in-vehicle camera, and attributes thereof, Data necessary for light distribution control such as position is calculated. Based on the calculated data, the electronic control unit determines a light distribution pattern corresponding to the traveling scene.
Then, the electronic control device determines a control amount of the light-emitting device necessary for realizing the light distribution pattern. Here, the control amount is, for example, the position and range of the light-shielding region, and based on this control amount, the control content of each light-emitting element in the light-emitting device (lights on / off, input power, etc.) is determined.

  The electronic control device is usually connected to the light emitting device via a driver. Therefore, the determined control content is sent to the light emitting device by the driver, and lighting and extinguishing of a specific light emitting element in the light emitting device are controlled.

  Embodiments of a drive substrate, a light emitting device, and a light distribution variable headlamp system according to the present disclosure will be specifically described below with reference to the drawings.

Embodiment 1
(Drive board)
The driving substrate 10 used in the light emitting device 90 in this embodiment includes a substrate 13, a first wiring 11, and a second wiring 12 as shown in FIG. 1A.
The substrate 13 has a single layer structure made of aluminum nitride. For example, the size is 10 mm × 10 mm and the thickness is 0.5 mm.

  The first wiring 11 and the second wiring 12 are formed on the first main surface 13a of the substrate 13 by a TiW / Cu / Ni / Au laminated structure from the substrate 13 side. The TiW and Cu films are respectively formed on the substrate 13 by sputtering using a mask with thicknesses of 0.1 μm and 0.1 μm, respectively, and Ni and Au films are formed on the surfaces thereof by plating, respectively 1.27 μm. , Having a thickness of 1.5 μm.

  For example, when the first main surface 13a of the substrate 13 is an xy plane, four first wirings 11 are arranged extending in the x-axis direction as the first direction as indicated by arrows. For example, the first wiring 11 has a width Q of 100 μm and a length of 3 mm. An interval between adjacent first wirings 11 is 500 μm.

  The second wirings 12 are arranged in a number corresponding to four so as to form a pair of four first wirings 11 along the y-axis direction as the second direction as indicated by arrows (12x, 12y, 12z, 12w). However, the second wirings 12 arranged along the y-axis direction are separated from each other by three between the first wirings 11 and two at the front end of the first wiring 11 and the other end side different from the first wirings 11. Has been. One second wiring 12 branches into two on the other end side. Therefore, two of the second wirings 12 are disposed adjacent to each other between the first wirings 11 and on the leading end side of the first wiring 11. The width M of the second wiring 12 is 540 μm, the width N1 and N2 of one branch of the second wiring 12 is 220 μm, and the distance between the second wirings 12 adjacent to the branch is 100 μm. Is 480 μm.

  Thus, since the 2nd wiring 12 is divided by the 1st wiring 11, in the state of drive board 10, each 2nd wiring 12 is not electrically connected. However, by connecting the divided second wirings 12 by mounting a light emitting element to be described later, a plurality of electrically conductive second wirings 12, here four, are connected to the first wirings 11. It arrange | positions so that it may become. As a result, a driving substrate capable of driving and controlling a plurality of light emitting elements independently of each other can be obtained.

  The first wiring 11 and the second wiring 12 are respectively connected to the routing wirings 11 a and 12 a on the other end side different from the tip, and the routing wirings 11 a and 12 a are connectors arranged at the end portion of the drive substrate 10. It extends to the pad electrodes 11b and 12b for use.

In the drive substrate 10 having such a configuration, since the matrix wiring can be formed in a single layer structure on the single-layer substrate 13, the width, length, interval, etc. of the wiring can be freely changed. A plurality of light emitting elements can be mounted with high density. In particular, since it is not necessary to form the matrix wiring with a multilayer structure, its thickness or size can be further reduced. In addition, due to the single layer structure, even when the light emitting elements are arranged at a high density, the heat due to the heat generated by the light emitting elements is quickly released from the front and back surfaces without entering the inside of the substrate, and the heat dissipation is further improved. It can be made even better.
Since the process of manufacturing such a driving substrate is very simple, an increase in manufacturing cost can be suppressed. Furthermore, it is possible to obtain a highly accurate driving substrate by avoiding expansion and contraction of the substrate or the like.

(Light emitting device)
As shown in FIGS. 2C and 2D, the light emitting device 90 of this embodiment is configured by mounting 16 light emitting elements 14 on the drive substrate 10 described above, as shown in FIG. 1B.
For example, as illustrated in FIGS. 1D, 1E, and 1F, the light emitting element 14 includes a semiconductor stacked body SC including a first conductive layer, a light emitting layer, and a second conductive layer stacked on a sapphire substrate S. The first electrode 15 and the second electrode 16 are formed on the same surface side.
As shown in FIG. 1C, the first electrode 15 and the second electrode 16 are disposed inside the light emitting element 14 in a plan view. For example, the first electrode 15 has a circular shape having a diameter of about ¼ to ３ of one side of the light emitting element 14, and is arranged at the center of the light emitting element 14. The second electrode 16 is disposed so as to surround the first electrode 15 and has an outer shape substantially equal to or slightly smaller than that of the light emitting element 14.

  Since the surface position of the semiconductor layer to which the first electrode 15 and the second electrode 16 are connected is different, the surface of the semiconductor layer on which these electrodes are formed inherently has a step. However, by controlling the thickness of the conductive single layer film or laminated film, such as the thickness of the first electrode and the second electrode or the electrode for external connection connected to the first electrode and the second electrode, the first electrode The surfaces of the electrode 15 and the second electrode 16 are formed so as to form substantially the same plane, that is, the surfaces thereof are positioned at the same height.

  When such a light emitting element 14 is mounted on the drive substrate 10, the light emitting element 14 is flip-chip mounted. In the present embodiment, the first electrode 15 is connected to the first wiring 11 via a stud bump made of Au, and the second electrode 16 is connected to the second wiring 12 via a stud bump made of Au. Connected with.

For example, when the second electrode 16 and the second wiring 12 are connected by a solder material such as AuSn as the bonding member, the solder material spreads along the shape of the second electrode 16. As shown in FIG. 1B and FIG. 1C, a part of the first wiring 11 faces the second electrode 16 of the light emitting element 14. Therefore, when such a bonding member is used, a protective film made of, for example, SiO ₂ is formed in a region facing the second electrode 16 of the first wiring 11, so that the first wiring 11, the second electrode, To prevent short circuit. Even when a material other than a solder material such as AuSn is used (for example, when a bump is used), it is preferable to form a protective film.
Specifically, as shown in FIGS. 1D to 1F, at least two connection portions 16a and 16b, for example, four connection portions 16a, 16b, 16c, and 16d are exposed on the surface of the second electrode 16. The protective film 19 is preferably formed so that the first electrode 15 is also exposed.

The light emitting element 14 includes two second wirings in which the first electrode 15 disposed in the center is disposed on both sides of the first wiring 11 so as to be separated from each other (two on one side when branched). 12 is fixed by the joining member so as to be arranged at the center in the x-axis direction. In addition, both sides of the second electrode 16 disposed so as to surround the first electrode 15 are fixed by the bonding member so as to be disposed on the two second wirings 12, respectively. As a result, the second wirings 12 are electrically connected in the y direction by the light emitting elements 14 at portions that are not crossed but separated from each other.
Therefore, it is possible to drive and control each light emitting element independently. As a result, any number of light emitting elements at arbitrary positions can be selected and turned on or off. Further, the power level can be controlled only in an arbitrary light emitting element, and brightness can be given in the light emitting device.
In addition, since the second electrode 16 is connected to the second wiring 12 divided by the plurality of connecting portions 16a to 16d, conduction in the second direction is reduced via the second electrode. Can be made.

  In the light emitting element 14, a phosphor layer is disposed as a wavelength conversion layer 17 on the surface opposite to the drive substrate 10. The wavelength conversion layer 17 has substantially the same size and shape as the light emitting element 14. The wavelength conversion layer 17 is made of glass containing YAG, is uniform over the entire thickness, and is 100 μm.

The sixteen light emitting elements 14 mounted on the driving substrate 10 are integrally formed on all side surfaces of the light emitting element 14 and a reflecting member 18 that is in contact with the light emitting element 14 and the driving substrate 10. .
The reflecting member 18 is made of a silicone resin containing 30% by weight of TiO ₂ . The size of the reflecting member 18 is about 2.5 × 2.5 mm and the thickness is about 0.25 mm.
The reflection member 18 also covers all the side surfaces of the wavelength conversion layer 17, and the upper surface thereof coincides with the upper surface of the wavelength conversion layer. Thereby, it is possible to reliably extract the light of the lit light emitting element from the light extraction surface regardless of the blinking of the adjacent light emitting elements.

  As shown in FIG. 1G, the light-emitting device 90 having such a configuration has a configuration in which a matrix circuit is completed by mounting the light-emitting elements, so that any number of light-emitting elements can blink freely. Can be controlled.

The light emitting device described above can be manufactured as follows.
First, as shown in FIG. 2A, a drive substrate 10 and a light emitting element 14 are prepared.
The light emitting elements 14 are mounted in a 4 × 4 matrix via stud bumps. The interval between the light emitting elements 14 is, for example, 100 μm.

  Next, as illustrated in FIG. 2B, the wavelength conversion layer 17 is placed on each of the light emitting elements 14. The wavelength conversion layer 17 is fixed to the light emitting element 14 using a translucent adhesive, for example.

  Thereafter, as shown in FIG. 2C, the 16 light emitting elements 14 are integrally covered with the reflecting member 18. The reflecting member 18 is formed by, for example, a molding method using upper and lower molds. All the side surfaces of the light emitting element 14 and the space between the light emitting element 14 and the substrate 13 are covered with the reflecting member 18, and the upper surface of the reflecting member 18 is made to coincide with the upper surface of the wavelength conversion layer.

Modified Example 1: Drive Substrate The drive substrate 20 in this modified example includes a substrate 13, a first wiring 21, and a second wiring 22, as shown in FIG. 3A. The first wiring 21 and the second wiring 22 are arranged to extend in the x-axis direction and the y-axis direction, respectively, in order to arrange the light emitting elements in a 3 × 3 matrix.

As shown in the first wirings 21x, 21y, and 21z, the first wirings 21 are arranged extending in parallel with each other in the x-axis direction.
The second wirings 22 are arranged in a number corresponding to three so as to be a pair of three first wirings 21 along the y-axis direction, as indicated by the second wirings 22x, 22y, and 22z. . However, the second wirings 22x, 22y, and 22z arranged along the y-axis direction are two between the first wirings 21, one at the tip of the first wiring 21, and on the other end side different from this. One is arranged so as to be separated from each other by four.
The width M of the second wiring 22 is 540 μm, and its length is 480 μm. The width Q of the first wiring 21 is 100 μm.
Except for these configurations, the configuration is substantially the same as that of the drive substrate of the first embodiment.

As shown in FIG. 3B, on such a drive substrate 20, the light emitting element 14 includes two second wirings 22 in which the first electrode disposed in the center is disposed on both sides of the first wiring 21. It is fixed by the joining member so as to be arranged at the center in the x-axis direction. Further, both sides of the second electrode that surrounds the first electrode are fixed by the joining member so as to be disposed on the two second wirings 22, respectively.
As a result, the first wiring 21 and the second wiring 22 are electrically connected to each other in a low resistance state in the x-th direction and the y-direction by the light-emitting element 14 at a portion where they intersect but are separated from each other. It will be. Therefore, it has substantially the same effect as the driving substrate of the first embodiment.

Embodiment 2
(Drive board)
As shown in FIG. 4A, the drive substrate 30 in this embodiment includes a substrate 13, a first wiring 31, and a second wiring 32. The first wiring 31 and the second wiring 32 are arranged in the x-axis direction and the y-axis direction, respectively, in order to arrange the light emitting elements in a 3 × 3 matrix.

Three first wires 31 are arranged extending in the x-axis direction. However, one first wiring 31 is branched into three.
The second wirings 32 are arranged along the y-axis direction in a number corresponding to three so as to form pairs of the first wirings 31 corresponding to three, as indicated by the second wirings 32x, 32y, and 32z. ing. However, the second wirings 32 arranged along the y-axis direction are two between the first wirings 31, one at the tip of the first wiring 31, and one at the other end side different from this. Each of them is arranged to be separated by four.
Except for these configurations, the configuration is substantially the same as that of the drive substrate of the first embodiment.

(Light emitting element)
In the light emitting device of this embodiment, as shown in FIG. 4C, the light emitting element 24 includes a semiconductor stacked body SC including a first conductive layer, a light emitting layer, and a second conductive layer stacked on a sapphire substrate S. A first electrode 15 and a second electrode 16 are formed on the same surface side of the stacked body SC.
Three first electrodes 15 are arranged in parallel to each other inside the light emitting element 24 in a plan view so as to correspond to the pattern of the first wiring of the driving substrate described above. The first electrode 15 has a width of about 70 μm and a length of about 420 μm. As for the 2nd electrode 16, the connection parts 16a-16g are arrange | positioned 4 each at the upper and lower sides in parallel with respect to these 1st electrodes 15, respectively.
Except for these configurations, the configuration is substantially the same as that of the light-emitting device of the first embodiment.

As shown in FIG. 4B, on such a drive substrate 30, the light-emitting element 14 includes two second wirings 32 in which the first electrode disposed in the center is disposed on both sides of the first wiring 31. It is fixed by the joining member so as to be arranged at the center in the x-axis direction. In addition, both sides of the second electrode arranged so as to surround the first electrode are fixed by the joining member so as to be arranged on the two second wirings 32, respectively.
As a result, the first wiring 31 and the second wiring 32 are electrically connected to each other in the low resistance state in the x-th direction and the y-direction by the light-emitting element 14 in a portion that is not crossed and separated from each other. Will be. Therefore, it has substantially the same effect as the driving substrate of the first embodiment.

Deformability 2: Drive Substrate The drive substrate 40 in this modification includes a substrate 13, a first wiring 41, and a second wiring 42 as shown in FIG. 5A. The first wiring 41 and the second wiring 42 are arranged in the x-axis direction (step shape) and the y-axis direction, respectively, in order to arrange the light emitting elements in a 3 × 3 matrix.

Three first wirings 41 are arranged extending stepwise in the x-axis direction.
The second wirings 42 are arranged in a number corresponding to three so as to be a pair of three first wirings 41 along the y-axis direction, as indicated by the second wirings 42x, 42y, and 42z. . However, the second wirings 42 arranged along the y-axis direction are two between the first wirings 41, one at the tip of the first wiring 41, and one at the other end side different from this. Each of them is arranged to be separated by four. Note that the three second wirings 42 are arranged so as to be shifted in the y-axis direction corresponding to the respective stages of the first wirings 41.
Except for these configurations, the configuration is substantially the same as that of the drive substrate of the first embodiment.

As shown in FIG. 5B, on the driving substrate 40, the light emitting element 14 includes two second wirings 42 in which the first electrode disposed in the center is disposed on both sides of the first wiring 41. It is fixed by the joining member so as to be arranged at the center in the x-axis direction. In addition, both sides of the second electrode that surrounds the first electrode are fixed by the bonding member so as to be disposed on the two second wirings 42, respectively.
As a result, the first wiring 21 and the second wiring 42 are electrically connected to each other in a low resistance state in the x-th direction and the y-direction by the light-emitting element 14 in a portion that is not crossed and separated from each other. Will be. Therefore, it has substantially the same effect as the driving substrate of the first embodiment.

Embodiment 6: Light Distribution Variable Headlamp System As shown in FIG. 6A, a light distribution variable headlamp system 50 according to this embodiment includes the light-emitting device according to Embodiment 2 as a light distribution variable headlamp 51, and further forward. An in-vehicle camera 52 that recognizes the position of the vehicle and an electronic control unit 54 that determines an area to be shielded and a light distribution pattern are provided.

  The light emitting device functions as a pair of light distribution variable headlamps 51 for vehicles disposed on the left and right sides of the vehicle. In addition to the light emitting elements, the light emitting device includes a projection lens and a lamp body that houses them.

The in-vehicle camera 52 captures an image in front of the vehicle and transmits the captured result to the electronic control unit 54 via the driver 53.
The electronic control unit 54 is usually composed of a microcomputer including a CPU, RAM, ROM, I / O and the like. The ROM stores a program for performing light distribution control. The RAM is used as a work area when the CPU performs various calculations.

(Control flow)
The light distribution variable headlamp system 50 configured as described above can be controlled as shown in FIG. 6B.
First, the in-vehicle camera 52 acquires necessary data from the front of the vehicle (S10). The data is, for example, data such as an image in front of the vehicle, a vehicle speed, an inter-vehicle distance, a running road shape, and a light distribution pattern. The acquired data is transmitted to the electronic control unit 54.
The electronic control unit 54 performs data processing based on the acquired data (S20). By data processing, attributes of objects in front of the vehicle (signal lights, illumination lights, etc.), attributes of vehicles (oncoming vehicles, preceding vehicles, people), vehicle speed, distance between vehicles, object brightness, road shape (lane width, straight road) Etc. are calculated.
Next, the electronic control unit 54 determines an appropriate light distribution pattern based on the calculated data (S30). The selected control light distribution pattern is, for example, a high beam light distribution pattern, a condensing light distribution pattern when the vehicle speed is high, a diffuse light distribution pattern when the vehicle speed is low, or a low beam distribution when an oncoming vehicle is detected. Light pattern and the like.
The electronic control unit 54 determines a control amount of turning on / off and / or turning on power of each light emitting element in the light distribution variable headlamp 51 according to the determined light distribution pattern (S40).

The electronic control unit 54 converts the determined control amount into driver data, and controls the driving of the light distribution variable headlamp 51 through the driver 53 (S50). That is, an arbitrary number of light emitting elements at arbitrary positions in the light distribution variable headlamp 51 are individually turned on or off to realize a desired light distribution pattern.
A series of these flows is repeated at predetermined time intervals.

  According to the light distribution variable headlamp system of this embodiment, when a vehicle, for example, a front vehicle such as an oncoming vehicle or a preceding vehicle or a person facing the front appears while traveling with a high beam of a headlamp, It is possible to detect the position of a vehicle or a person in front with a camera, shield only that position, and irradiate other positions with a high beam. That is, it is possible to automatically adjust the area to be shielded from the headlight irradiation area in accordance with the position of the vehicle in front or the person, and avoid giving glare to the driver or person in the vehicle in front. On the other hand, the driver can always secure a field of view close to that of high beam travel, making it easy to see pedestrians, road signs, distant road shapes, etc., and can contribute to safe driving.

  The drive substrate of the present disclosure can be used for mounting various electric elements such as a semiconductor element and a light emitting element. In addition, a light-emitting device using this can execute operation, blinking, and the like in each light-emitting element. By using this light emitting device, it can be used as a variable light distribution headlamp system capable of controlling an area to be shielded and a light distribution pattern in units of light emitting elements.

10, 20, 30, 40 Driving board 11, 11x, 11y, 11z, 11w, 21, 31, 41 First wiring 11a, 12a, 21a, 22a, 31a, 32a, 41a, 42a Lead wiring 11b, 12b, 21b, 22b, 31b, 32b, 41b, 42b Pad electrode 12, 12x, 12y, 12z, 12w, 22, 22x, 22y, 22z, 32, 32x, 32y, 32z, 42, 42x, 42y, 42z Second wiring 13 Substrate 13a 1st main surface 14, 24 Light emitting element 15 1st electrode 16 2nd electrode 16a-16h Connection part 17 Wavelength conversion layer 18 Reflective member 19 Protective film 50 Light distribution variable headlamp system 51 Light distribution variable headlamp 52 Car-mounted camera 53 Driver 54 Electronic Control Device 90 Light Emitting Device S Sapphire Substrate SC Semiconductor Stack

Claims (12)

A substrate having a first major surface;
A plurality of first wirings formed on the first main surface and extending in a first direction;
A plurality of second wirings formed on the first main surface, extending in the second direction, and being divided and disposed;
A plurality of light emitting devices including a first electrode and a second electrode disposed on the same surface side of the semiconductor multilayer structure;
The first electrode is connected to face the first wiring,
The second electrode includes a first connection portion and a second connection portion connected to the first connection portion, and faces the second wiring, and is divided into at least two second portions separated in the second direction. It is connected to the first connection part and the second connection part across the wiring,
The light emitting device, wherein the plurality of light emitting elements are arranged along the second direction.   The light emitting device according to claim 1, wherein the first electrode and the first wiring or the second electrode and the second wiring are connected by a stud bump or a solder ball.   The light emitting device according to claim 1, wherein the second electrode is disposed so as to surround the first electrode, and upper surfaces of the first electrode and the second electrode form a same plane.   The first wiring has a region disposed opposite to the second electrode, and an insulating protective film is formed on the surface of the first wiring or the surface of the second electrode in the region. The light-emitting device according to claim 1.   The light emitting device according to claim 1, wherein a reflective member is formed between the plurality of light emitting elements so as to be in contact with a side surface of the light emitting element.   The light emitting device according to claim 1, wherein the plurality of light emitting elements are independently driven control type.   The light emitting device according to claim 1, wherein the first wiring and the second wiring are formed of the same metal material.   The light emitting device according to claim 1, wherein the substrate is a single layer ceramic.   The light emitting device according to claim 1, wherein the first wiring and the second wiring are regularly arranged in a matrix direction.   The light emitting device according to claim 1, wherein the first wiring or the second wiring is partially branched.   The light emitting device according to claim 1, wherein the second wiring is wider than the first wiring. The light emitting device according to any one of claims 1 to 11,
An in-vehicle camera that recognizes the position of the vehicle ahead,
A light distribution variable headlamp system comprising an area to be shielded and an electronic control device for determining a light distribution pattern.