Light emitting device

Abstract

A light emitting device (100) has a light emitting substrate (10) having a circuit pattern layer (34) provided on one face of an insulating substrate (32) and a plurality of light emitting elements (20) bonded to the circuit pattern layer (34), the light emitting substrate (10) having a phosphor layer (36) provided on the one face side (i.e., the surface (31) side) of the insulating substrate (32) and containing a phosphor having a peak wavelength of luminescence when excited by light emitted from at least one of the light emitting elements (20) in a visible light region, the plurality of light emitting elements (20) having a plurality of series of the light emitting elements (20) connected in series, the plurality of series of the light emitting elements (20) being arranged side by side from an inner side to an outer side of a substrate surface of the light emitting substrate (10) when the light emitting substrate (10) is viewed in plan, and anode sides of the plurality of series of the light emitting elements (20) being arranged on the same side of either the inner side or the outer side of the substrate surface.

Description

Technical Field

[0001] This invention relates to light-emitting devices. Background Technology

[0002] Patent document 1 discloses an LED lighting device having a substrate on which a light-emitting element (LED element) is mounted.

[0003] Patent Document 1: Chinese Patent Publication No. 106163113

[0004] For example, in the case of the LED lighting fixture in Patent Document 1, no lighting technology for efficiently emitting light from multiple light-emitting elements is disclosed, thus requiring a new technology. Summary of the Invention

[0005] The object of the present invention is to provide a technique for efficiently emitting light in a light-emitting device having a light-emitting substrate having an insulating substrate and a plurality of light-emitting elements, thereby realizing, for example, a high-output lighting device.

[0006] The light-emitting device of the present invention includes a light-emitting substrate having a circuit pattern layer disposed on one side of an insulating substrate and a plurality of light-emitting elements bonded to the circuit pattern layer.

[0007] The aforementioned light-emitting substrate has a phosphor layer disposed on one side of the aforementioned insulating substrate, and includes a phosphor whose emission peak wavelength is located in the visible light region when the emission of at least one light-emitting element is used as excitation light.

[0008] The aforementioned multiple light-emitting elements comprise multiple series bodies formed by connecting multiple light-emitting elements in series.

[0009] When viewed from above, the aforementioned multiple interconnected structures are arranged side-by-side from the inside of the substrate surface toward the outside.

[0010] The anode sides of the aforementioned plurality of series-connected bodies are disposed on the same side of either the inner side or the outer side of the aforementioned substrate surface.

[0011] In a light-emitting device having a light-emitting substrate with an insulating substrate and multiple light-emitting elements, efficient light emission is achieved, thereby enabling, for example, a high-output lighting device. Attached Figure Description

[0012] Figure 1 This is a simplified diagram of the light-emitting device according to the embodiment.

[0013] Figure 2 This is a diagram showing the internal structure of the light-emitting device in a simplified manner according to an embodiment.

[0014] Figure 3 This is a top view of the light-emitting substrate according to the embodiment.

[0015] Figure 4 This is a top view of the light-emitting substrate showing the circuit pattern layer of the embodiment.

[0016] Figure 5 This is a circuit diagram that schematically illustrates the connection method of the light-emitting elements in the embodiment.

[0017] Figure 6 This is a circuit diagram of the first parallel connection in the implementation method.

[0018] Figure 7 This is a diagram used to explain the light-emitting operation of the light-emitting substrate in the embodiment.

[0019] Figure 8 This diagram is used to illustrate the light-emitting action of a light-emitting substrate in a comparative mode. Detailed Implementation

[0020] "summary"

[0021] The following is for reference Figures 1 to 7 This embodiment will now be described. First, refer to... Figure 1 and Figure 5 The function and structure of the light-emitting device 100 of this embodiment will be explained. Next, referring to... Figure 3 The light-emitting operation of the light-emitting device 100 of this embodiment will be explained. Next, the effects of this embodiment will be explained.

[0022] <Function and Structure of Light-Emitting Device>

[0023] Figure 1 This is a perspective view of the light-emitting device 100 according to this embodiment. Figure 2 It is a cross-sectional view that schematically represents the internal structure.

[0024] The light-emitting device 100 is generally conical or cylindrical in shape, and is used, for example, as a high-output lighting device for use in stadium lighting or exterior lighting of large-scale buildings (so-called tower lighting).

[0025] The light-emitting device 100 includes: a light-emitting substrate 10, a heat dissipation unit (heat sink 40 and cooling fan 50), a housing 60 (frame), and a drive control circuit 80 (power conversion unit, driver IC, switch unit, etc.). Here, the light-emitting substrate 10, the heat dissipation unit (heat sink 40 and cooling fan 50), and the drive control circuit 80 are housed in the housing 60.

[0026] The housing 60 is configured to include a conical peripheral wall 62 and, for example, an upper wall 66 made of a material with good thermal conductivity (e.g., aluminum alloy). A cooling opening 69 is provided in the peripheral wall 62, which is circumferentially arranged near the upper end and communicates between the inside and outside of the housing 60. Furthermore, as a component of the housing 60, a transparent or white cover is provided to cover the light-emitting substrate 10, but this is omitted here.

[0027] Here, the light-emitting substrate 10 is approximately circular in shape when viewed from above. The light-emitting substrate 10 is disposed on the upper surface 66A of the upper wall 66. The light-emitting substrate 10 is fixed to the upper surface 66A of the upper wall 66, for example, by means of a through hole 39 provided near the periphery.

[0028] (Heat dissipation unit (radiator 40, cooling fan 50))

[0029] The heat sink 40 is disposed on the inner surface 66B of the upper wall 66, and more specifically, on the portion of the upper wall 66 opposite to the light-emitting substrate 10 (in the lower direction in the figure). The heat sink 40 has a plurality of heat sink fins extending and protruding in the lower direction.

[0030] The cooling fan 50 is disposed inside the housing 60, that is, on the side opposite to the light-emitting substrate 10 across the heat sink 40 (lower side of the figure). The cooling fan 50 is disposed inside the housing 60 opposite to the light-emitting substrate 10. When the light-emitting device 100 is activated, the airflow generated by being powered by the power source (e.g., the drive control circuit 80) hits the heat sink 40 and is discharged from the cooling opening 69.

[0031] [Light-emitting substrate 10]

[0032] Next, the main references are... Figures 3-5 The light-emitting substrate 10 will be described below. Figure 3 This is a top view of the light-emitting substrate 10 as observed from the surface 30A side. Figure 4 From Figure 3 The light-emitting substrate 10 is shown in a top view with the light-emitting element 20 and phosphor layer 36 omitted, i.e., the circuit pattern layer is exposed. Figure 5 This diagram schematically illustrates the arrangement of the light-emitting elements 20 in the light-emitting substrate 10 and clearly shows their connection method (circuit state). In other words, it shows... Figure 3 The diagram shows a simplified version of the light-emitting substrate 10, and some components (temperature sensor 75, substrate pressure bar 38, etc.) are omitted.

[0033] like Figure 3 As shown, when viewed from the surface 30A side and the back side 30B side, i.e., from the thickness direction, the light-emitting substrate 10 is circular as an example.

[0034] The light-emitting substrate 10 includes: multiple light-emitting elements 20, a phosphor substrate 30, multiple connectors 70, a temperature sensor 75, and electronic components such as a driver IC (not shown). That is, multiple light-emitting elements 20 and the aforementioned electronic components are mounted on the phosphor substrate 30.

[0035] The drive control circuit 80 is, for example, located adjacent to the cooling fan 50, and uses PWM control to enable the operation of the fan via wire 71 (see reference). Figure 5 The light-emitting element 20 connected to the circuit emits light. In addition, the drive control circuit 80 acquires the signal from the temperature sensor 75 and controls the drive of the cooling fan 50 to maintain the desired temperature range.

[0036] A through hole of a predetermined diameter (hereinafter referred to as "central opening 37") is provided approximately in the center of the light-emitting substrate 10. A plurality of connectors 70 and temperature sensors 75 are arranged around the central opening 37 in a manner that surrounds the central opening 37. The wires 71 for supplying power to the light-emitting element 20 and the signal lines of the temperature sensors 75 are connected to the drive control circuit 80 via the central opening 37.

[0037] In addition, such as Figure 1 and Figure 2 As shown, the light-emitting substrate 10 is fixed to the upper wall 66 by making its back side contact the upper surface 66A of the upper wall 66 that forms part of the housing 60.

[0038] [Multiple light-emitting elements 20]

[0039] Multiple light-emitting elements 20 are, as an example, housed in a CSP (Chip Scale Package) containing flip-chip LEDs (illustration omitted). For example, Figure 3 As shown, a plurality of light-emitting elements 20 are regularly arranged on the phosphor substrate 30, covering the entire surface 30A of the light-emitting substrate 10 (phosphor substrate 30).

[0040] Here, multiple light-emitting elements 20 are arranged radially. More specific connection methods will be described later, but they are formed by arranging multiple series of light-emitting elements 20 side by side, so that these series are arranged radially.

[0041] The correlated color temperature of the light emitted by each light-emitting element 20 is, for example, 6,000K. Furthermore, in this embodiment, the phosphor substrate 30 is cooled, for example, to a temperature range of room temperature (e.g., 25°C) to 100°C, by means of the heat sink 40 and the cooling fan 50 during the light-emitting operation of the plurality of light-emitting elements 20.

[0042] Here, if we were to supplement the meaning of “~” used in this specification for numerical ranges, for example, “50℃~100℃” means “above 50℃ and below 100℃”. That is, “~” used in this specification for numerical ranges means “above the part before the “~” and below the part after the “~”.

[0043] [Connection method of multiple light-emitting elements 20]

[0044] Reference Figure 3 , Figure 5 and Figure 6 The connection method of the light-emitting element 20 will be explained. Additionally, Figure 6 It is focused on Figure 5 The diagram shows a portion of the region (a parallel body).

[0045] Multiple light-emitting elements 20 are regularly arranged on the surface 31 side of the insulating substrate 32. More specifically, the series connection of multiple light-emitting elements 20 is configured such that the anode side is the connector 70 side and the ground (GND) side is the outer peripheral side.

[0046] In this embodiment, a parallel body is provided, consisting of multiple series-connected bodies connected in parallel. Furthermore, the multiple parallel bodies are disposed on the phosphor substrate 30.

[0047] To explain in more detail. For example... Figure 5 As shown, for convenience, the area of ​​the light-emitting substrate 10 is divided into four equal parts along the circumference when viewed from above, namely the first substrate area 10A to the fourth substrate area 10D.

[0048] Each of the first substrate region 10A to the fourth substrate region 10D has two parallel bodies and three connectors 70 that supply power to them. That is, a total of eight parallel bodies are provided (in...). Figure 5 The first parallel circuit (11) to the eighth parallel circuit (18) are connected in the middle. Each parallel circuit has the same connection method (circuit structure).

[0049] Specifically, a first parallel connector 11 and a second parallel connector 12 are provided in the first substrate region 10A. The anode side of the first parallel connector 11 (here, the side of the central opening 37) is connected to the connector 70(+). Similarly, the anode side of the second parallel connector 12 is connected to the connector 70(+). In addition, the ground (GND) sides of the first parallel connector 11 and the second parallel connector 12 are connected to the connector 70(GND) by wiring from the outer periphery to the center (side of the central opening 37) through a grounding pattern provided on the circuit pattern layer 34.

[0050] Similarly, a third parallel connector 13 and a fourth parallel connector 14 are provided in the second substrate region 10B. The anode side (here, the side with the central opening 37) of the third parallel connector 13 is connected to the connector 70(+). The anode side of the fourth parallel connector 14 is connected to the connector 70(+). In addition, the ground (GND) sides of the third parallel connector 13 and the fourth parallel connector 14 are connected to the connector 70(GND) by wiring from the outer periphery to the center (side with the central opening 37) through a grounding pattern provided on the circuit pattern layer 34.

[0051] Similarly, a fifth parallel connector 15 and a sixth parallel connector 16 are provided in the third substrate region 10C. The anode side (here, the side with the central opening 37) of the fifth parallel connector 15 is connected to the connector 70(+). The anode side of the sixth parallel connector 16 is connected to the connector 70(+). In addition, the ground (GND) sides of the fifth parallel connector 15 and the sixth parallel connector 16 are connected to the connector 70(GND) by wiring from the outer periphery to the center (side with the central opening 37) through a grounding pattern provided on the circuit pattern layer 34.

[0052] Similarly, a seventh parallel connector 17 and an eighth parallel connector 18 are provided in the fourth substrate region 10D. The anode side (here, the side with the central opening 37) of the seventh parallel connector 17 is connected to the connector 70(+). The anode side of the eighth parallel connector 18 is connected to the connector 70(+). In addition, the ground (GND) sides of the seventh parallel connector 17 and the eighth parallel connector 18 are connected to the connector 70(GND) by wiring from the outer periphery to the center (side with the central opening 37) through a grounding pattern provided on the circuit pattern layer 34.

[0053] A wire 71 is connected to connector 70(+) and is connected to the aforementioned drive control circuit 80 through the central opening 37. Additionally, a wire 71 is connected to connector 70(GND) and is connected to the designated ground (GND).

[0054] Next, refer to Figure 6 The connection method of the parallel circuits will be explained. The first parallel circuit 11 to the eighth parallel circuit 18 have the same connection method (circuit structure). Hereinafter, the first parallel circuit 11 will be described as an example.

[0055] The first parallel body 11 has multiple series bodies connected in parallel, and more specifically, it has a first series body 21 to a fifth series body 25. The anode side of the first series body 21 to the fifth series body 25 is connected to the connector 70(+). The cathode side of the first series body 21 to the fifth series body 25 is connected to ground (GND) via the connector 70 (GND).

[0056] The first series circuit 21 to the fifth series circuit 25 have the same connection method (circuit structure). Specifically, the first series circuit 21 is a structure formed by connecting multiple light-emitting elements 20, here the first light-emitting element 20a to the tenth light-emitting element 20j in series. The second to tenth series circuits are also similarly formed by connecting the first light-emitting element 20a to the tenth light-emitting element 20j in series.

[0057] In each of the first series 21 to the fifth series 25, the first light-emitting element 20a to the tenth light-emitting element 20j are arranged in a generally straight line from the center side (central opening 37 or connector 70 side) towards the outer periphery. However, the arrangement of the first light-emitting elements 20a to the tenth light-emitting elements 20j does not need to be perfectly straight. In order to optimize the light distribution on the phosphor substrate 30, some or all of them can be arranged in a zigzag pattern. In other words, multiple light-emitting elements 20 (first light-emitting element 20a to tenth light-emitting element 20j) can be connected such that the anode side of each series (i.e., the first series 21 to the fifth series 25) is located at the center side (central opening 37 side) and the cathode side (GND side) is the periphery side.

[0058] Furthermore, the light-emitting color of the light-emitting element 20 can be different for each series body and for each parallel body. When the drive control circuit 80 drives the light-emitting element 20 to emit light, the output is adjusted for each series body and each parallel body (wherein, for each body connected to the same connector 70), or the timing of the light emission is adjusted, thereby enabling multi-color dimming and color adjustment.

[0059] [Phosphor substrate 30]

[0060] The phosphor substrate 30 has an insulating substrate 32, a circuit pattern layer 34, a phosphor layer 36, and a back pattern layer (omitted) (see, for example, reference). Figure 3 and Figure 4 ).exist Figure 4 In the text, phosphor layer 36 is omitted, but as... Figure 3 As shown, phosphor layer 36 is used as an example to cover the electrode pair 34A in circuit pattern layer 34 (see reference). Figure 4 The phosphor layer 36 is disposed on the surface 31 of the insulating substrate 32 in a manner that excludes the portion inside the magnified circle X, the electrical connection portion with the connector 70, and the electrical connection portion with the temperature sensor 75. That is, when the phosphor substrate 30 is viewed from above, the phosphor layer 36 is disposed on the entire surface except for the area where the light-emitting element 20, connector 70 and other constituent elements on the substrate are disposed.

[0061] A plurality of (here, 8) through holes 39 are provided at equal intervals along the circumferential direction near the outer edge of the phosphor substrate 30. Additionally, a plurality of (4) through holes 39 are provided at equal intervals along the circumferential direction near the central opening 37 (more specifically, near the outer periphery of the connector 70). Through these through holes 39, the phosphor substrate 30 (i.e., the light-emitting substrate 10) can be fixed to the housing 60. Furthermore, as... Figure 3 As shown, a substrate pressure bar 38 is installed to prevent substrate warping / lifting.

[0062] Furthermore, the phosphor substrate 30 of this embodiment is manufactured by processing (etching, etc.) a mother plate on which copper foil layers are provided on both sides of the insulating substrate 32, as described later. For example, the mother plate is CS-3305A manufactured by Lichang Industrial Co., Ltd.

[0063] [Insulating substrate 32]

[0064] The insulating substrate 32, as an example, has the following characteristics: As described above, it is circular when viewed from both the surface 31 side and the back side 33 side. The material, as an example, is an insulating material comprising bismaleimide resin and glass cloth. The thickness, as an example, is 100 μm.

[0065] The coefficients of thermal expansion (CTE) in both the longitudinal and transverse directions are, for example, less than 10 ppm / ℃ in the range of 50℃ to 100℃. Alternatively, from another perspective, the CTE in both the longitudinal and transverse directions is, for example, 6 ppm / ℃. This value is almost identical to that of the light-emitting element 20 in this embodiment (90% to 110%, i.e., within ±10%).

[0066] The glass transition temperature, for example, is above 300°C.

[0067] As an example, the energy storage modulus is greater than 1.0 × 10⁻⁶ in the temperature range of 100℃ to 300℃. 10 Pa < 1.0 × 10 11 Pa.

[0068] For example, the longitudinal and transverse flexural moduli are 35 GPa and 34 GPa respectively under normal conditions.

[0069] The longitudinal and transverse thermal flexural moduli, as an example, are 19 GPa at 250°C. The water absorption rate, as an example, is 0.13% after being placed at 23°C for 24 hours. The relative permittivity, as an example, is 4.6 at 1 MHz under normal conditions. The dielectric loss tangent, as an example, is 0.010 at 1 MHz under normal conditions.

[0070] [Circuit pattern layer 34]

[0071] The circuit pattern layer 34 is a metal layer (for example, a copper foil layer) disposed on the surface 31 of the insulating substrate 32 and is conductive to the connector 70. The circuit pattern layer 34 has the function of supplying power from the power source (drive control circuit 80) via the wires 71 connected to the connector 70 to the plurality of light-emitting elements 20.

[0072] Therefore, as Figure 4 As shown inside the magnified circle X, a portion of the circuit pattern layer 34 becomes a plurality of electrode pairs 34A that respectively connect the plurality of light-emitting elements 20. That is, the circuit pattern layer 34 is connected to each light-emitting element 20.

[0073] Multiple light-emitting elements 20 are regularly arranged on the surface 31 side of the insulating substrate 32 as described above. More specifically, multiple series of light-emitting elements 20 connected in series are arranged radially. Here, each series is configured such that the anode side is the connector 70 side and the cathode side is the outer peripheral side. According to this arrangement of light-emitting elements 20, multiple electrode pairs 34A are also regularly arranged throughout the entire surface 31. Hereinafter, in this specification, the portion of the circuit pattern layer 34 other than the multiple electrode pairs 34A will be referred to as the wiring portion 34B.

[0074] In the surface 31 of the insulating substrate 32, the proportion of the circuit pattern layer 34 (the proprietary area of ​​the circuit pattern layer 34) is, for example, more than 60% of the surface 31 of the insulating substrate 32.

[0075] Furthermore, the wiring portion 34B extending from the cathode-side connector 70 (GND) of the first parallel body 11 to the eighth parallel body 18 is formed to be connected with... Figure 1 , Figure 3 The areas where the substrate pressure bar 38 is provided overlap, thereby achieving a highly efficient configuration of the light-emitting element 20.

[0076] [Fluorescent layer 36]

[0077] In this embodiment, the phosphor layer 36 is provided on the surface 31 of the insulating substrate 32 in such a way that it covers the portion of the circuit pattern layer 34 other than the plurality of electrode pairs 34A and the aforementioned electrical connection portion. Moreover, in this embodiment, the proportion occupied by the phosphor layer 36 (the proprietary area of ​​the phosphor layer 36) is, as an example, 80% or more relative to the surface 31 of the insulating substrate 32.

[0078] The phosphor layer 36, for example, comprises a phosphor (an aggregate of multiple phosphor particles) as described later and an adhesive, and is an insulating layer in which the multiple phosphor particles are dispersed in the adhesive. The phosphor contained in the phosphor layer 36 has the property of being excited by the emission of each light-emitting element 20 as excitation light. Specifically, the phosphor of this embodiment has the property of having an emission peak wavelength in the visible light region when the emission of the light-emitting element 20 is used as excitation light. Furthermore, the adhesive can be, for example, an epoxy-based, acrylate-based, or silicone-based adhesive, as long as it is a material with the same insulating properties as the adhesive contained in the solder resist.

[0079] As an example, the phosphor included in phosphor layer 36 is one or more phosphors selected from the group consisting of an α-type thionon phosphor containing Eu, a β-type thionon phosphor containing Eu, a CASN phosphor containing Eu, and a SCASN phosphor containing Eu. Furthermore, the phosphor described above is just one example in this embodiment; other visible light-excited phosphors such as YAG, LuAG, and BOS can also be phosphors other than those described above.

[0080] α-thione phosphors containing Eu are given by the general formula: M x Eu y Si 12-(m+n) Al (m+n) O n N 16-n In the above general formula, M is an element selected from the group consisting of Li, Mg, Ca, Y and lanthanides (excluding La and Ce), containing at least one element of Ca. When the valence of M is set to a, it is ax + 2y = m, where x is 0 < x ≤ 1.5, 0.3 ≤ m < 4.5, and 0 < n < 2.25.

[0081] β-type thionolite containing Eu is produced using the general formula: Si 6-z Al z O z N 8-z (z = 0.005~1) indicates that divalent europium (Eu) is dissolved in the β-type thionium as the luminescent center. 2+ ) fluorescent particles.

[0082] In addition, examples of nitride phosphors include CASN phosphors containing Eu and SCASN phosphors containing Eu.

[0083] CASN phosphors containing Eu (an example of nitride phosphors) are, for example, those using the formula CaAlSiN3:Eu 2+ It means that Eu 2+It is a red phosphor with a reactive agent and a matrix of crystals composed of alkaline earth silica nitrides. Furthermore, in the definition of Eu-containing CASN phosphors in this specification, Eu-containing SCASN phosphors are excluded.

[0084] SCASN phosphors containing Eu (an example of nitride phosphors) are, for example, those using the formula (Sr,Ca)AlSiN3:Eu 2+ It means that Eu 2+ A red phosphor with a activator and a matrix of crystals composed of alkaline earth silica nitrides.

[0085] [Back Pattern Layer]

[0086] The back pattern layer (not shown) is a patterned metal layer (for example, a copper foil layer) disposed on the back side 33 of the insulating substrate 32. Alternatively, the back pattern layer may be an independent floating layer. As an example, the back pattern layer overlaps with at least 80% of the area of ​​the circuit pattern layer 34 disposed on the surface 31 in the thickness direction of the insulating substrate 32. As an example, the proportion of the back pattern layer on the back side 33 of the insulating substrate 32 (the proprietary area of ​​the back pattern layer) is at least 80% of the back side 33 of the insulating substrate 32.

[0087] <Light-emitting device's light-emitting action>

[0088] Next, refer to Figure 7 and Figure 8 The light-emitting operation of the light-emitting device 100 in this embodiment will be explained.

[0089] When the power is on, the drive control circuit 80 drives the light-emitting element 20 to emit light. Additionally, the drive control circuit 80 supplies power to the cooling fan 50 and performs temperature detection processing based on the temperature sensor 75. Based on the detection results from the temperature sensor 75, the drive control circuit 80 performs feedback control on the cooling fan 50 to maintain the desired temperature range.

[0090] [Light emission action of the light-emitting substrate]

[0091] Multiple light-emitting elements 20 emit light in a radial pattern, scattering light L (reference). Figure 7 A portion of the emitted light L reaches the surface 30A of the phosphor substrate 30. The operation of the emitted light L will be explained below by defining its travel direction.

[0092] A portion of the light L emitted from each light-emitting element 20 does not penetrate the phosphor layer 36 but exits to the outside of the housing 60. In this case, the wavelength of the light L remains the same as the wavelength of the light L emitted from each light-emitting element 20.

[0093] Additionally, a portion of the light L emitted from each light-emitting element 20 contains the light from the flip-chip LED itself, which is incident on the phosphor layer 36. Here, the "light from the flip-chip LED itself in a portion of the light L" refers to the light in the emitted light L that is not color-converted by the phosphor of each light-emitting element 20 (CSP itself), i.e., the light from the flip-chip LED itself (for example, blue light (wavelength around 470nm)).

[0094] Furthermore, if the light L from the flip-chip LED itself collides with the phosphor dispersed in the phosphor layer 36, the phosphor is excited to generate excitation light. The reason for phosphor excitation here is that the phosphor dispersed in the phosphor layer 36 is a phosphor with an excitation peak for blue light (visible light excitation phosphor).

[0095] Consequently, since a portion of the energy of light L is used to excite the phosphor, light L loses some energy. As a result, the wavelength of light L is converted (wavelength conversion occurs). For example, depending on the type of phosphor in phosphor layer 36 (e.g., in the case where a red CASN is used as the phosphor), the wavelength of light L will become longer (e.g., 650 nm).

[0096] Furthermore, although the excitation light in phosphor layer 36 remains emitted from phosphor layer 36 as before, a portion of the excitation light is directed towards the circuit pattern layer 34 below (see reference). Figure 4 ).

[0097] Furthermore, the excitation light directed toward the circuit pattern layer 34 is reflected outward through the circuit pattern layer 34. For example, when the wavelength of the excitation light of the phosphor is 600 nm or higher, a reflection effect can be expected even if the circuit pattern layer 34 is Cu. When the wavelength of the excitation light is less than 600 nm, a reflection effect can be expected if the circuit pattern layer 34 or its surface is, for example, Ag (electroplated).

[0098] Furthermore, depending on the type of phosphor in phosphor layer 36, the wavelength of light L differs from the examples described above, but in any case, wavelength conversion of light L is performed.

[0099] As described above, the light L emitted by each light-emitting element 20 (the light L emitted radially by each light-emitting element 20) is irradiated to the outside along with the excitation light through multiple optical paths as described above. Therefore, when the emission wavelength of the phosphor contained in the phosphor layer 36 is different from the emission wavelength of the phosphor of the flip-chip LED sealed (or covered) in the light-emitting element 20 (CSP), the light-emitting substrate 10 of this embodiment irradiates the excitation light along with the beam of light L emitted by each light-emitting element 20 as a beam of light L containing a wavelength different from the wavelength of light L emitted by each light-emitting element 20. For example, the light-emitting substrate 10 of this embodiment irradiates a composite light of the light (wavelength) emitted by the light-emitting element 20 and the light (wavelength) emitted by the phosphor layer 36.

[0100] In contrast, when the emission wavelength of the phosphor contained in the phosphor layer 36 is the same as the emission wavelength of the phosphor of the flip-chip LED sealed (or covered) in the light-emitting element 20 (CSP) (in the case of the same correlated color temperature), the light-emitting substrate 10 of this embodiment irradiates the light L emitted by each light-emitting element 20 together with the excitation light as a beam of light L containing the same wavelength as the light L emitted by each light-emitting element 20.

[0101] Furthermore, in this embodiment (refer to...) Figure 7 ), compared to the case without fluorophore layer 36 (refer to Figure 8 Unlike other materials, light is also irradiated from phosphor layer 36, thus reducing glare from the irradiated light.

[0102] Furthermore, in this embodiment, the phosphor layer 36 completely covers the surface 31 side of the insulating substrate 32. Additionally, a portion of the light emitted from each light-emitting element 20 enters the phosphor layer 36, generating heat during excitation. This heat is dissipated to the outside via the aforementioned heat sink 40 and cooling fan 50.

[0103] The above is an explanation of the light-emitting operation of the light-emitting substrate 10.

[0104] <Effects of the Implementation Method>

[0105] The features and effects of this embodiment are described.

[0106] (1) A light-emitting device 100, characterized in that,

[0107] The light-emitting substrate 10 has a circuit pattern layer 34 disposed on one side (here, surface 31) of an insulating substrate 32, and a plurality of light-emitting elements 20 bonded to the circuit pattern layer 34.

[0108] The light-emitting substrate 10 has a phosphor layer 36, which is disposed on one side (i.e., the surface 31 side) of the insulating substrate 32 and includes a phosphor whose emission peak wavelength is located in the visible light region when the emission of at least one light-emitting element 20 is used as excitation light.

[0109] The aforementioned plurality of light-emitting elements 20 comprises a plurality of series bodies (here, the first series body 21 to the fifth series body 25) formed by connecting the plurality of light-emitting elements 20 in series.

[0110] When viewed from above, the substrate surface of the light-emitting substrate 10 shows multiple interconnected units arranged side-by-side from the inside of the substrate surface toward the outside.

[0111] The anode sides of the aforementioned plurality of series-connected bodies are disposed on the same side of either the inner side or the outer side of the aforementioned substrate surface.

[0112] That is, multiple series of light-emitting elements 20 connected in series are provided. Furthermore, in each series, the anode side is disposed on either the inner (central) side or the outer (peripheral) side of the substrate surface. In the above embodiment, the anode side is configured such that, when viewed from above, the light-emitting substrate 10 (phosphor substrate 30) becomes the central side of the substrate outline, and the grounding side becomes the outer edge of the substrate outline. Therefore, since the anode sides of the multiple series are integrated on either the inner (central) or outer (peripheral) side of the substrate surface, the freedom of wiring and mounting of the light-emitting elements 20 is increased. That is, the connector 70 connected to the series can be integrated in the center of the substrate. In particular, as in the above embodiment, the above effect becomes significant when the anode side is disposed on the inner (central) side of the substrate surface and the cathode side (grounding side) is disposed on the outer (peripheral) side of the substrate surface. That is, the grounding (GND) can be, for example, made common to the multiple series (so-called base GND), thus increasing the original design freedom. However, the anode side needs to be connected to the drive control circuit 80. Therefore, if the anode side of the series circuit becomes the outer edge of the light-emitting substrate 10, the configuration of the connector 70 and the wiring of the wires 71 extending from the connector 70 become complicated. As a result, the freedom of configuration of the light-emitting elements 20 decreases, making it difficult to achieve a high-output light-emitting device 100. However, according to this embodiment, as described above, there is no such concern, and the efficiency and integration of the configuration of the light-emitting elements 20 can be further improved, enabling the realization of a high-output (high-brightness) light-emitting device 100.

[0113] (2) It may also have a parallel body formed by connecting at least a portion of the above-mentioned series bodies in parallel (here, the first parallel body 11 to the fourth parallel body 14).

[0114] By having a structure that connects the series of light-emitting elements 20 into a parallel structure, connectors 70 and wires 71 can be provided, thereby enabling a highly efficient circuit construction.

[0115] (3) Multiple parallel bodies can also be set up.

[0116] It can be equipped with connector 70 and wire 71, thereby enabling efficient circuit construction.

[0117] (4) The light emission color of each of the above parallel units (here, the first parallel unit 11 to the fourth parallel unit 14) can also be different. That is, the light emission element 20 can also be different for each parallel unit.

[0118] This enables multi-color lighting, allowing for the output of various lighting colors by adjusting the output for each parallel element.

[0119] (5) For each of the above-mentioned parallel bodies (here, the first parallel body 11 to the fourth parallel body 14), the emission peak wavelength of the phosphor layer 36 in the region of the parallel body (here, the first substrate region 10A to the fourth substrate region 10D) can also be set.

[0120] The fluorescence color of the phosphor layer 36 in at least one parallel region is different from the fluorescence color of the other parallel regions. By adjusting the output of the light-emitting element 20, the illumination color of the light-emitting device 100 can be adjusted. In addition, as in (4), when the light-emitting element 20 has different emission colors, it is further possible to achieve a variety of illumination colors.

[0121] (6) The above-mentioned series bodies (first series body 21 to fifth series body 25) can also be arranged radially.

[0122] This allows for the efficient configuration of the light-emitting elements 20 (especially those in series).

[0123] (7) The shape of the light-emitting substrate 10 (in other words, the phosphor substrate 30) can also be approximately circular.

[0124] This makes the configuration of the light-emitting element 20, i.e., the distribution of light emission, more uniform, and makes it easier to adjust the light emission.

[0125] (8) It may also include: a connector 70 disposed on the central side of the radial shape presented by the light-emitting substrate 10, and connected to the series assembly; and

[0126] The conductor 71 is connected to the connector 70 and is used to supply power to the series conductor.

[0127] Since the series of light-emitting elements 20 are arranged radially, the connector 70 can be integrated in the center of the radial shape, that is, the central area of ​​the circle, so it is easy to integrate the wire 71 connected to the connector 70.

[0128] (9) The light-emitting substrate 10 may also have an opening (here, a central opening 37) extending through the substrate thickness direction in the radial central region.

[0129] The wire 71 connected to the connector 70 is connected to the drive control circuit 80 of the light-emitting element 20 disposed inside the frame through the opening (central opening 37).

[0130] The wire 71 is introduced into the housing 60 through the central opening 37 near the connector 70, so the wiring of the wire 71 does not become complicated and a simple construction can be achieved.

[0131] (10) The light-emitting substrate 10 may further include a temperature sensor 75.

[0132] By positioning the temperature sensor 75 near the center of the substrate, i.e. near the central opening 37, the signal line (wire) connected to the temperature sensor 75 and the wire 71 connected to the connector 70 (i.e. the light-emitting element 20) can be wired together as a single unit.

[0133] (11) It may further include a heat dissipation unit (here, a heat sink 40, a cooling fan 50, etc.) which dissipates the heat of the light-emitting substrate that is heated along with the light emission of the light-emitting element 20.

[0134] As described above, the present invention has been illustrated using the various embodiments described above as examples, but the present invention is not limited to the embodiments described above. Any structure that at least achieves the first effect described above is included within the scope of the present invention.

[0135] This application claims priority based on Japanese Patent Application No. 2020-142373, filed on August 26, 2020, the entire contents of which are incorporated herein by reference.

[0136] Explanation of reference numerals in the attached figures

[0137] 10…Light-emitting substrate; 10A~10D…First to fourth substrate regions; 11~18…First to eighth parallel units; 20…Light-emitting element; 30…Phosphor substrate; 30A, 31…Surface; 30B, 33…Back side; 32…Insulating substrate; 34…Circuit pattern layer; 34A…Electrode pair; 34B…Wiring portion; 36…Phosphor layer; 37…Terminal; 39…Through hole; 40…Heat sink; 50…Cooling fan; 60…Housing; 62…Peripheral wall; 64…Bottom wall; 66…Top wall; 69…Cooling opening; 75…Temperature sensor; 80…Drive control circuit; 100…Light-emitting device; L…Light.

Claims

1. A light-emitting device, characterized in that, The device includes a light-emitting substrate, which has a circuit pattern layer disposed on one side of an insulating substrate and a plurality of light-emitting elements bonded to the circuit pattern layer. The light-emitting substrate has a phosphor layer disposed on one side of the insulating substrate, and includes a phosphor whose emission peak wavelength is located in the visible light region when the emission of at least one light-emitting element is used as excitation light. The plurality of light-emitting elements comprises a plurality of series bodies formed by connecting multiple light-emitting elements in series, and a parallel body formed by connecting at least a portion of the series bodies in parallel with each other. When viewed from above, the plurality of interconnected structures are arranged side-by-side from the inside of the substrate surface toward the outside of the substrate surface. The anode sides of the plurality of series bodies are disposed on the same side of either the inner side or the outer side of the substrate surface. The phosphor layer does not cover the light-emitting element. A substrate pressure bar is mounted on the light-emitting substrate, and the area where the substrate pressure bar is located overlaps with the wiring portion extending from the cathode side of the parallel body towards GND.

2. The light-emitting device according to claim 1, characterized in that, The phosphor layer does not cover the electrical connections, i.e., electrode pairs, between the light-emitting element and the circuit pattern layer.

3. The light-emitting device according to claim 1, characterized in that, The phosphor layer accounts for more than 80% of the surface area of ​​the insulating substrate.

4. The light-emitting device according to claim 1, characterized in that, The parallel system is configured in multiple ways.

5. The light-emitting device according to claim 1, characterized in that, Each of the parallel components emits a different color.

6. The light-emitting device according to any one of claims 1 to 5, characterized in that, For each of the parallel structures, the emission peak wavelength of the phosphor layer in the region where the parallel structure is located is set.

7. The light-emitting device according to any one of claims 1 to 4, characterized in that, The series of components are arranged radially.

8. The light-emitting device according to any one of claims 1 to 5, characterized in that, The light-emitting substrate is circular in shape.

9. The light-emitting device according to any one of claims 1 to 5, characterized in that, have: A connector is disposed on the central side of the radial shape presented by the light-emitting substrate and is connected to the series body; and A wire, which is connected to the connector, is used to supply power to the series conductor.

10. The light-emitting device according to any one of claims 1 to 5, characterized in that, The light-emitting substrate has a through-hole in the radial central region. The light-emitting element is connected to the drive control circuit of the light-emitting element disposed inside the frame through the opening.

11. The light-emitting device according to any one of claims 1 to 5, characterized in that, The light-emitting substrate further includes a temperature sensor.

12. The light-emitting device according to any one of claims 1 to 5, characterized in that, It further includes a heat dissipation unit that dissipates heat from the light-emitting substrate that rises in temperature as the light-emitting element emits light.

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