JP6477149B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device.

  A light emitting device such as an illumination is configured by mounting a large number of LED elements on a substrate having a single circular mounting region. In addition, light-emitting devices that combine a phosphor with an LED element and mix the light emitted by the LED element with the fluorescence emitted by the phosphor excited by the light and output light are also widespread. For example, an illuminating device that emits white light by combining a blue LED and a YAG phosphor that emits yellow light when excited by the blue light is used for illumination purposes.

  In this case, as shown in the plan view of FIG. 9, the mounting region 22 on the mounting substrate 20 constituting the light emitting device often has a circular outer shape. On the other hand, the LED element 91 is generally rectangular. For this reason, an unmounted area UA in which the LED element 91 cannot be mounted is generated in the circular peripheral portion, as indicated by hatching in FIG. In such a configuration, since the LED element 91 does not exist in the circular peripheral portion, the amount of light is relatively reduced, which causes uneven brightness.

  Further, when a phosphor is applied on the mounting region 22 on which the LED element 91 is mounted, as shown in a cross-sectional view of FIG. 10 (corresponding to a cross-sectional view taken along line XX in FIG. 9), the vicinity of the outer edge of the mounting region 22 In the area CA, an area where only the phosphor 32 is applied without the LED element 91 is generated. In this portion, the distance of the phosphor 32 excited by the light emitted from the LED element 91 differs from position to position, and there is a problem that color unevenness occurs in a circular light emitting region.

  On the other hand, as shown in FIG. 11A and FIG. 11B, when the LED elements are cut out from the circular semiconductor wafer, a configuration is proposed in which the divided LED elements are combined and arranged in a circular shape by dividing into fan shapes. (Patent Document 1). According to this configuration, a plurality of LED elements can be combined to form a circle.

  However, in this configuration, since the circular semiconductor wafer is divided and then combined again to restore the circular shape, the size of the light emitting device is limited to the size of the semiconductor wafer. In other words, there is a problem that light-emitting devices having different sizes cannot be obtained and lack flexibility.

JP 2005-109113 A

  The present invention has been made in view of such a conventional background. An object of the present invention is to provide a light-emitting device that can easily generate a light-emitting device of an arbitrary size and suppress the occurrence of uneven brightness and color unevenness.

According to the light emitting device according to one aspect of the present invention, a substrate having a circular mounting area, and a plurality of elements arranged in a matrix at regular intervals on the mounting area are rectangular. A first light emitting element and a plurality of the light emitting elements arranged on the mounting area and around the mounting area of the first light emitting element so as to follow a circular outer edge of the mounting area. A second light emitting element, the second light emitting element emits light of the same emission color as the first light emitting element, and the area of the second light emitting element is the area of the first light emitting element. against it is set to 0.8 to 1.2 times.

  With the above configuration, the luminance of each light emitting element can be made almost constant, and in particular, the occurrence of color unevenness in the peripheral portion of the substrate having a circular mounting region can be suppressed. In addition, by making the areas of the first light emitting element and the second light emitting element substantially equal, the amount of current and the amount of heat generated can be made substantially constant. The situation that causes unevenness can be avoided.

It is a top view which shows the light-emitting device which concerns on Embodiment 1 of this invention. It is sectional drawing in the II-II line of FIG. It is a top view which shows an example of a 2nd light emitting element. It is a top view which shows the other example of a 2nd light emitting element. It is sectional drawing which shows the light-emitting device which concerns on Embodiment 2 of this invention. It is a top view which shows the light-emitting device which concerns on Embodiment 3 of this invention. It is sectional drawing in the VII-VII line of FIG. It is a top view which shows the light-emitting device which concerns on Embodiment 4 of this invention. It is a top view which shows the conventional light-emitting device. It is sectional drawing which shows the other conventional light-emitting device. 11A and 11B are plan views showing a conventional light emitting device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below is an example for embodying the technical idea of the present invention, and the present invention is not limited to the following. Moreover, this specification does not specify the member shown by the claim as the member of embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention only to specific examples unless otherwise specifically described. Only. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing. In addition, the contents described in some examples and embodiments may be used in other examples and embodiments. Further, in this specification, the term “upper” as used on the layer or the like is not necessarily limited to the case where the upper surface is formed in contact with the upper surface, but includes the case where the upper surface is formed apart. It is used to include the case where there is an intervening layer between them.

  According to the light emitting device according to an embodiment, the first light emitting element and the second light emitting element emit light having a first peak wavelength, and are disposed above the first light emitting element and the second light emitting element. In addition, a wavelength conversion member that converts light having a first peak wavelength emitted from the first light emitting element and the second light emitting element into light having a second peak wavelength different from the first peak wavelength is provided. Thereby, it is possible to output mixed color light in which the light having the first peak wavelength emitted from the first light emitting element and the second light emitting element and the light having the second peak wavelength emitted from the wavelength conversion member are mixed. With the above configuration, when outputting mixed light of light emitted from the light emitting element and the wavelength conversion member, it is possible to suppress the occurrence of color unevenness in the peripheral portion of the circular mounting region.

  According to the light emitting device according to another embodiment, the wavelength conversion member can be directly provided on the upper surface of the circular mounting region, the first light emitting element, and the second light emitting element. With the above configuration, conventionally, an unmounted region without the first light emitting element is generated between the periphery of the first light emitting element group and the outer edge of the circular mounting region, and color unevenness is caused by the wavelength conversion member provided in this portion. A situation in which the second light emitting element is arranged in the unmounted region can be avoided.

  In the light emitting device according to another embodiment, the first light emitting element can be formed in a square shape.

  In the light emitting device according to another embodiment, the second light emitting element has a right triangle shape, the short side is substantially the same length as one side of the first light emitting element, and the hypotenuse is doubled. Can do.

  In the light emitting device according to yet another embodiment, the second light emitting element includes a hexagonal growth substrate, and the M surface of the growth substrate is included on the side surface including the short side and the side surface including the oblique side. it can.

  In the light emitting device according to another embodiment, the second light emitting element has a right triangle shape, the short side is substantially the same length as one side of the first light emitting element, and the long side is twice as long. be able to.

According to the light emitting device according to another embodiment, in the circular outer edge, there are a plurality of areas where one or more outermost first light emitting elements arranged along the outer edge of the mounting area are arranged, The first light emitting element is disposed between the regions . Further, one or more second light emitting elements can be arranged between these regions and in a region along the outer edge. With the above configuration, the rectangular first light emitting element has a triangular second light emission in the gap portion where it is difficult to arrange the circumference and the gap so as not to occur along the outer edge of the circular mounting region. By arranging the elements and reducing the gap, the amount of output light can be increased while maintaining the size of the circular mounting region. In addition, a light emitting device with less luminance unevenness can be realized by making an area where light emitting elements are spread close to a circle and making the light emitting area circular.

According to the light emitting device according to another embodiment, the area of the second light emitting element can be set to 0.8 to 1.2 times the area of the first light emitting element.
(Embodiment 1)

  FIG. 1 shows a plan view of the light emitting device 100 according to Embodiment 1 of the present invention. The light-emitting device 100 shown in this figure includes a mounting substrate 20, a plurality of first light-emitting elements 1 disposed on a circular mounting region 22 formed on the mounting substrate 20, and a plurality of second light-emitting elements 2. With. Each light emitting element has a top surface as a light emitting region.

  The mounting substrate 20 has a rectangular outer shape in plan view, and a mounting region 22 for mounting a plurality of light emitting elements is formed on the upper surface. As the mounting substrate 20, a glass epoxy substrate, a ceramic substrate, or the like can be used.

  On the mounting area 22, a plurality of first light emitting elements 1 are arranged in a matrix at regular intervals. Each of the first light emitting elements 1 has a rectangular outer shape in plan view. A square shape is preferable. In the present specification, the “matrix shape” is not limited to a matrix shape arranged vertically and horizontally, but includes a state in which they are obliquely or staggered.

  On the other hand, the second light emitting element 2 is disposed around the first light emitting element group 10 on which the plurality of first light emitting elements 1 are mounted and between the outer edges of the mounting region 22. Specifically, when the first light emitting element 1 formed in a rectangular shape is disposed in the mounting area 22, the circular mounting area 22 on the mounting substrate 20 can be separated by a completely rectangular first light emitting element 1 alone. It is difficult to fill without. Therefore, an unmounted area UA in which the first light emitting elements are not arranged is partially generated between the periphery of the first light emitting element group 10 and the outer edge of the mounting area 22 (area indicated by oblique lines in the plan view of FIG. 9). In this case, in the unmounted area UA at the outer edge of the mounting area 22, the light amount is relatively decreased as compared with other areas, which causes a decrease in luminance and luminance unevenness. Furthermore, the light emission pattern by the first light emitting element group 10 appears with a different outline from the outer edge of the original mounting region, which is not preferable in terms of appearance.

Therefore, as shown in FIG. 1, a second light emitting element 2 having a different shape from the first light emitting element 1, specifically, a second light emitting element 2 having a triangular shape is prepared, and the outer edge of the mounting region and the first light emitting element 2 are prepared. The second light emitting element 2 is arranged in a gap with the periphery of the element group 10. In this way, as shown in the cross-sectional view of FIG. 2, the unmounted area UA can be reduced, and a light emission pattern along the outer edge of the mounting area 22 can be realized, and a high output that makes the best use of the mounting area can be obtained.
(Second light emitting element 2)

  The second light emitting element 2 is preferably configured such that the area of the light emitting region is substantially equal to the area of the light emitting region of the first light emitting element 1. By doing in this way, the brightness | luminance of the 1st light emitting element 1 and the 2nd light emitting element 2 can be made substantially equal, and generation | occurrence | production of the color nonuniformity especially in the outer peripheral part of the mounting area | region 22 can be suppressed. Also, by making the areas of the first light-emitting element 1 and the second light-emitting element 2 substantially equal, the amount of current and the amount of heat generated in each light-emitting element can be made substantially constant, so the first light-emitting element 1 and the second light-emitting element 2 It is possible to avoid a large difference in the degree of degradation of the. From this result, it is possible to suppress the occurrence of color unevenness due to the difference in deterioration for each light emitting element. In the present specification, the area of the second light-emitting element 2 is substantially equal to the area of the first light-emitting element 1 is used in the meaning including 0.8 to 1.2 times the area of the first light-emitting element. To do. Preferably, it is about 0.866 with respect to the area of a 1st light emitting element.

  In addition, the emission color of light emitted from the second light emitting element 2 is preferably matched with the emission color of the first light emitting element 1. That is, it is preferable that the first light emitting element 1 and the second light emitting element 2 emit light having a common first peak wavelength. Since the peak wavelength of the semiconductor light emitting element generally varies somewhat between light emitting elements manufactured from the same semiconductor wafer, it does not require exact coincidence with the common first peak wavelength. . Moreover, if it is a range which is visually recognized as the same color by human eyes, it can be handled as the same emission color. Therefore, also in this specification, such a slight variation is allowed and treated as a common peak wavelength or emission color.

  In the example of FIG. 1, the first light emitting element 1 is formed in a square shape. On the other hand, the second light emitting element 2 is formed in a right triangle shape. The right triangle is composed of a short side, a long side, and a hypotenuse, and an angle formed between the short side and the long side is 90 °. As described above, it is preferable that the area of the light emitting region of the second light emitting element 2 is substantially equal to that of the first light emitting element 1. For example, when the length of one side of the first light emitting element 1 is 1, the second light emitting element 2 has a short side length of 1, a long side length of 2, and an oblique side length of 2, as shown in FIG. √5≈2.24. Thereby, the areas of the first light emitting element 1 and the second light emitting element 2 can be matched. In this right triangle, the angle between the hypotenuse and the short side is about 63.4 °, and the angle between the hypotenuse and the long side is about 26.6 °.

  On the other hand, when manufacturing a light emitting device, a semiconductor wafer is cut into pieces, and a hexagonal substrate such as sapphire is used as a semiconductor growth substrate, and a semiconductor layer grown on the growth substrate is used. Often, GaN-based semiconductor materials are used. When a GaN-based semiconductor material is grown on the C-plane of the sapphire substrate, the cleavage property appears on the M-plane of the growth substrate. When viewed in a plane, there is a 30 ° shift between the A-plane of the substrate and the M-plane of the semiconductor layer. As a result, when the semiconductor wafer is cleaved and the semiconductor light-emitting elements are singulated, 60 By cleaving in units of ° or 30 °, cleaving can be used to efficiently cleave, and the yield of the obtained semiconductor light emitting device can be improved. Therefore, it is preferable that the side surface including the short side and the side surface including the oblique side of the second light emitting element are manufactured so as to include the M plane of the growth substrate. As a result, as shown in FIG. 4, the second light emitting element 2 ′ can be formed in a right triangle having an angle between the short side and the long side of 60 °, which is advantageous in manufacturing the second light emitting element. .

  In this case, when the length of the short side of the second light emitting element 2 ′ is matched with the length of one side (for example, 1) of the square first light emitting element 1, the area of the second light emitting element 2 ′ is √3. /2≈0.87, which is slightly smaller than the area (for example, 1) of the first light emitting element 1. However, the difference is slight, and there is no practical problem that the luminance is remarkably lower than that of the first light emitting element or the degree of deterioration is remarkably large. On the other hand, since an advantage in manufacturing the second light-emitting element can be obtained, the present invention is not limited to the case where the area of the second light-emitting element is matched with that of the first light-emitting element, and includes cases where the area is slightly different. Specifically, the area of the second light emitting element is set to 0.8 to 1.2 times the area of the first light emitting element. If it is this range, the performance and lifetime of a 1st light emitting element and a 2nd light emitting element can be equated practically.

  The second light-emitting element 2 obtained in this way is a first light-emitting element group constituted by a plurality of first light-emitting elements 1 in a state where the plurality of first light-emitting elements 1 are arranged in the mounting region 22 in a matrix. 10 and the outline of the mounting area 22 are arranged. In the example of FIG. 1, the plurality of first light emitting elements 1 are arranged in a square shape inside the mounting region 22. For example, when the mounting region 22 is circular, a square inscribed in the circle is drawn, and the first light emitting elements 1 are arranged vertically and horizontally so as to fit within the square. In this example, 36 square-shaped first light emitting elements 1 of 6 vertical × 6 horizontal are arranged.

  Further, in this state, there is a gap between the large virtual square VS formed by the 36 first light emitting element groups 10 and the circle of the mounting region 22. Therefore, the first light emitting element 1 is further disposed in this gap. In the example of FIG. 1, the first light emitting elements 1 are arranged in two stages along each side of the virtual square VS, and the number of the first light emitting elements 1 in each stage is changed. Here, the number of the first light-emitting elements 1 in the lower stage is the same as that of the virtual square VS (six in the example of FIG. 1), and the number of the first light-emitting elements 1 in the upper stage is smaller than this (in FIG. 1). 2 in the example). By doing so, a plurality of square-shaped first light emitting elements 1 can be arranged in the mounting area of the circular mounting area 22 to the maximum extent. In addition, there is a fixed interval between adjacent first light emitting elements.

  Further, in this state, the triangular second light emitting element 2 is arranged. Here, among the first light emitting elements 1 arranged in two stages along each side of the virtual square VS, the upper first light emitting elements (two outermost first light emitting elements 1M) There is almost no gap between 22 outer edges. On the other hand, among the first light emitting elements on the lower side (six), the left and right first light emitting elements (two each) excluding the center (two) have a gap between the outer edge of the mounting region 22. (First unmounted area UA1 indicated by hatching in FIG. 9). More precisely, there is a triangular area (UA1 in FIG. 9) surrounded by the upper surface of the lower first light emitting element, the side surface of the upper first light emitting element, and the outer edge of the mounting area 22. To do. In this portion, the second light emitting element 2 formed in a right triangle shape is arranged. As a result, the region around the mounting region 22 that has been difficult to fill with a rectangular light emitting element can be filled with the triangular second light emitting element 2. With the above configuration, the light emission output can be improved by increasing the number of light emitting elements, and the light emitting pattern can be brought close to the circular shape of the mounting region 22, so that the high quality light emitting device 100 with less luminance unevenness can be obtained. .

  As a method for specifying the arrangement position of the second light emitting element 2, for example, the first light emitting element 1 is arranged in a cross shape passing through the center of the circle with respect to the circular mounting region 22 (in the example of FIG. 1). A set of two first light emitting elements arranged in a cross shape), and the outermost first of the first light emitting elements 1 arranged in a cross shape, that is, the outermost first arranged along the outer edge of the mounting region 22 Based on the light emitting element 1M, it is expressed that the second light emitting element 2 is arranged on the side of the outermost first light emitting element 1M or between the upper, lower, left and right outermost first light emitting elements 1M. You can also In other words, the second light emitting element 2 is generally located in a gap area between the outer surface of the first light emitting element group 10 in which a plurality of first light emitting elements 1 are arranged and configured in a lump shape and the outer surface of the mounting region 22. Although it can be said that the outermost first light emitting element 1M is arranged in the gap area in the example of FIG. 1, the outermost first light emitting element 1M is not arranged in the gap area. It can also be regarded as an area. In any case, by disposing the second light emitting element 2 in the gap area where the first light emitting element cannot be disposed, such a gap is reduced and the quality of the light emitting device 100 is improved.

  Note that the above example is an example, and the arrangement pattern of the first light emitting element and the second light emitting element includes the size (radius etc.) of the substrate having a circular mounting region, the shape and size of the first light emitting element ( The length of one side), the shape and size of the second light emitting element, the quality required for the light emitting device, and the like.

The first light emitting element 1 and the second light emitting element 2 are flip-chip mounted on the upper surface of the mounting region 22. Alternatively, it can be mounted by wire bonding or the like. The light-emitting element is a semiconductor element that emits light by applying a voltage, and a known semiconductor light-emitting element made of a nitride semiconductor or the like can be applied. In addition, a light emitting element having an arbitrary wavelength may be selected in order to obtain a desired emission color. Specifically, as a light emitting element that emits blue light (wavelength 430 nm to 490 nm) or green light (wavelength 490 nm to 570 nm), In _x Al _Y Ga _1-xy N (0 ≦ X, 0 ≦ Y, As a light emitting element that emits red light (wavelength: 620 nm to 750 nm) using a nitride semiconductor represented by X + Y ≦ 1), an arsenic compound or a phosphorus compound semiconductor represented by GaAlAs, AlInGaP, or the like is used. Further, a light-emitting element in which the emission color is changed depending on the mixed crystal ratio can be used. As the growth substrate for the semiconductor element, a hexagonal substrate such as sapphire or GaN is used.
(Wavelength conversion member 30)

  Further, the wavelength conversion member 30 can be included in the light emitting device. The wavelength conversion member 30 is a member that converts light having a first peak wavelength emitted from the first light emitting element 1 and the second light emitting element 2 into light having a second peak wavelength different from the first peak wavelength. As such a wavelength conversion member 30, a phosphor is preferably used.

  The wavelength conversion member 30 is disposed above the first light emitting element 1 and the second light emitting element 2. With such a configuration, the light emitting device outputs mixed light in which the first wavelength light emitted from the first light emitting element 1 and the second light emitting element 2 and the second wavelength light emitted from the wavelength conversion member 30 are mixed. be able to. With such a configuration, it is possible to suppress the occurrence of uneven color in the peripheral portion of the mounting region 22 when outputting the mixed color light of the light emitted from the light emitting element and the wavelength conversion member 30. For example, if a blue LED is used for the first light emitting element 1 and the second light emitting element 2 and a phosphor such as YAG is used for the wavelength conversion member 30, the blue light of the blue LED and the phosphor are emitted by being excited by the blue light. A light emitting device that outputs white light obtained by mixing yellow fluorescent light can be configured.

The wavelength conversion member 30 has a wavelength conversion member on a glass plate as a basic light transmission member, or a phosphor crystal that is a wavelength conversion member or a single crystal, a polycrystal, an amorphous body having a phase thereof, A sintered body, agglomerate, porous material, and a translucent material, for example, a translucent resin mixed in and impregnated with a ceramic body or phosphor crystal particles and a translucent material appropriately added thereto. Or a translucent member containing phosphor particles, for example, a molded body of translucent resin. In addition, it is preferable from a heat resistant viewpoint that a light transmissive member is comprised with inorganic materials rather than organic materials, such as resin. Specifically, it is preferably made of a translucent inorganic material containing a phosphor, and in particular, a sintered body of a phosphor and an inorganic substance (binding material, binder), or a sintered body or crystal made of a phosphor. This increases reliability. When a YAG phosphor is used as the wavelength converting member 30, in addition to a YAG single crystal or a high purity sintered body, a YAG / alumina sintered body using alumina (Al ₂ O ₃ ) as a binder, glass From the viewpoint of reliability, a sintered body using as a binder is preferable. Further, by making the light transmitting member into a plate shape, the coupling efficiency with the emission surface of the light emitting element 1 configured in a planar shape is good, and the light transmitting member can be easily aligned so as to be substantially parallel to the main surface of the light transmitting member. . In addition, by making the thickness of the light transmission member substantially constant, the amount of wavelength conversion of the light passing therethrough can be made substantially uniform, the color mixing ratio can be stabilized, and color unevenness at the site of the light emitting surface can be suppressed. For this reason, in the case where a plurality of first light emitting elements 1 are mounted on one light transmitting member, there is little unevenness in luminance and chromaticity distribution in the light emitting surface due to the arrangement of the individual first light emitting elements 1 and is substantially uniform. High luminance can be obtained.
(Embodiment 2)

  Here, as Embodiment 2, a schematic cross-sectional view of a light-emitting device 200 including the wavelength conversion member 30 is shown in FIG. In the light emitting device 200 shown in this figure, a translucent sealing member 40 is provided on a mounting region 22 on which a plurality of first light emitting elements 1 and second light emitting elements 2 are mounted. A wavelength conversion member 30 is disposed on the upper surface of the substrate. With such a configuration, the wavelength conversion member 30 is separated from the light emitting element, and the first light emitted from the light emitting element is avoided while avoiding the situation where the deterioration of the wavelength conversion member 30 is accelerated by the influence of light or heat emitted from the light emitting element. It becomes possible to convert light having a peak wavelength into light having a second peak wavelength.

  For the sealing member 40, a resin having translucency and excellent weather resistance can be suitably used. For example, polyolefin resin, polycarbonate resin, polystyrene resin, epoxy resin, acrylic resin, acrylate resin, methacrylic resin (PMMA, etc.), urethane resin, polyimide resin, polynorbornene resin, fluorine resin, silicone resin, modified silicone resin, modified epoxy Examples thereof include at least one resin selected from resins and the like.

The wavelength conversion member 30 absorbs at least a part of the light emitted from the first light emitting element 1 and the second light emitting element 2 and converts it into light of different wavelengths. For such a wavelength conversion member, for example, a phosphor can be suitably used. Moreover, the wavelength conversion member 30 can be a phosphor layer that is formed into a layer by containing a phosphor in a binder such as a resin. In addition to only one type of phosphor, a plurality of types can be mixed. A known material may be applied to the phosphor, for example, a YAG-based phosphor activated with Ce or the like by mixing Y (yttrium), Al (aluminum), and Ga (garnet), or a lanthanoid such as Eu or Ce. Nitride-based phosphors, oxynitride-based phosphors and the like mainly activated with a system element can be used. From these materials, in combination with the emission colors of the first light emitting element 1 and the second light emitting element 2, the light emitted from the irradiation region is selected so as to have a desired color. Examples include YAG phosphors and chlorosilicate phosphors that emit green and yellow, SCASN phosphors such as (Sr, Ca) AlSiN ₃ : Eu that emit red, and CASN phosphors such as CaAlSiN ₃ : Eu. In addition, two or more kinds of phosphors may be mixed and used.
(Embodiment 3)

  On the other hand, the wavelength conversion member can also be provided directly on the upper surface of the mounting region 22 and the upper surfaces of the first light emitting element 1 and the second light emitting element 2. Such an example is shown as a third embodiment in the schematic plan view of FIG. 6 and the enlarged schematic cross-sectional view of FIG. In the light emitting device 300 shown in these drawings, the phosphor 32 is directly applied as a wavelength conversion member on the mounting surface of the mounting region 22 in which the first light emitting element 1 and the second light emitting element 2 are mounted. As a method of applying the phosphor 32, sedimentation, electrodeposition, pulse spray, or the like can be used.

  As described above, in the configuration in which the phosphor 32 is directly applied to the mounting region, an excellent effect that uneven color can be reduced by applying the present invention is obtained. That is, in the conventional light emitting device using only the rectangular first light emitting element, the first light emitting element group 10 and the outer edge of the mounting region 22 are arranged as shown in the schematic plan view of FIG. An unmounted area UA without one light emitting element is generated. When the phosphor 32 is applied to the mounting area in this state, as shown in the cross-sectional view of FIG. 10, the phosphor 32 is applied to the unmounted area UA. As a result, the light wavelength-converted by the phosphor 32 from this area. Only will occur. For example, when a blue LED is used for the first light emitting element 1 and a YAG phosphor 32 is used for the phosphor 32, the wavelength conversion is performed between the blue light from the blue LED and the YAG phosphor 32 from the region where the first light emitting element 1 is mounted. As a result, white light which is a mixed color light with the yellow light is obtained. However, since there is no blue LED in the unmounted area UA, the phosphor is excited by the wavelength-converted yellow light, and as a result, the periphery of the white light is partially yellowed around the circular light emitting device. It became colored and caused uneven color.

On the other hand, in the light emitting device 300 according to the third embodiment, as shown in the plan view of FIG. 6, the second light emitting element 2 is conventionally disposed in the region that was the unmounted region UA. As shown in the cross-sectional view, since the combination of the second light emitting element 2 and the wavelength conversion member can be arranged also on the outer periphery of the mounting region 22, it is possible to obtain mixed color light as in other regions, and as a result, there is no color unevenness. Uniform and high-quality light can be obtained.
(Embodiment 4)

  In the above example, in addition to the first light emitting element 1, the light emitting element in which the second light emitting element 2 having a different shape is combined has been described. However, the present invention does not limit the type of light emitting element to be added to one type, and two or more types of light emitting elements having different shapes may be combined. With such a configuration, a more uniform light-emitting device can be obtained by more densely filling an unmounted region with a light-emitting element. As such an example, an example of a light emitting device to which the third light emitting element 3 is added is shown as a fourth embodiment in the plan view of FIG. In the example of the light emitting device 400, in addition to the first light emitting element 1 and the second light emitting element 2 described above, the third light emitting element 3 having a shape different from these is combined. The third light emitting element 3 is a right isosceles triangle. The third light emitting element 3 is disposed in a small gap region where the second light emitting element 2 cannot be disposed. In FIG. 8, the third light emitting element 3 is arranged in the second unmounted area UA <b> 2 formed between each vertex of the virtual square VS and the outer edge of the mounting area 22. As a result, the gap is further reduced as compared with the configuration of FIG. 1, and a high-output and high-quality light-emitting device 400 can be obtained. The third light emitting element 3 has a half area of the first light emitting element 1. That is, the phosphorous side of the right isosceles triangle of the third light emitting element 3 is made equal to the length of one side of the first light emitting element 1. However, since the light emitting area of the third light emitting element 3 is ½ that of the first light emitting element 1, it is disadvantageous in terms of life and heat generation. In addition, the use of a plurality of different light emitting elements is disadvantageous in terms of manufacturing effort and cost, and therefore, the light emitting device is appropriately selected according to the required quality and accuracy of the light emitting device. For example, in applications where accuracy is a priority, it is also possible to use four or more types of light emitting elements, such as using a fourth light emitting element of a different shape.

  Further, in the above example, a configuration in which a plurality of types of light-emitting elements manufactured in advance are mounted on a substrate having a circular mounting region that is a separate member has been described. However, different shapes of semiconductors are formed on a circular growth substrate. By growing the element structure, it is also possible to obtain a light emitting device with a reduced gap.

  As described above, the rectangular first light emitting elements are arranged in a matrix in the circular mounting area, and the second light emitting elements formed in a triangular shape having an area substantially equal to the first light emitting element are arranged around the first light emitting elements. By doing so, it is possible to obtain a high-quality light-emitting device with reduced luminance unevenness and color unevenness.

  A light emitting device according to an embodiment of the present invention includes a backlight light source, an illumination light source, a headlight, a display in which a light emitting element is used as a light source, a display, a traffic light, an illumination switch, an image scanner, and other various sensors and various indicators. It can utilize suitably for etc.

100, 200, 300, 400 Light emitting device 1 First light emitting element 1M Outermost first light emitting element 2, 2 ′ Second light emitting element 3 Third light emitting element 10 First light emitting element group 20 Mounting substrate 22 Mounting region 30 Wavelength converting member 32 Phosphor 40 Sealing member 91 LED element UA Unmounted area UA1 First unmounted area; UA2 ... Second unmounted area CA Outer edge vicinity area VS Virtual square

Claims (8)

A substrate having a circular mounting area;
On the mounting area, a plurality of light emitting elements arranged in a matrix at regular intervals, each light emitting element having a rectangular shape,
A second light emitting element having a triangular shape on each of the mounting regions, the plurality of the light emitting elements being arranged around the outer periphery of the first light emitting element along the circular outer edge of the mounting region; With
The second light emitting element emits light of the same emission color as the first light emitting element ,
Wherein the area of the second light-emitting element, Ru emitting device name is set to 0.8 to 1.2 times the area of the first light emitting element. The light-emitting device according to claim 1,
The first light emitting element and the second light emitting element emit light having a first peak wavelength,
Light having a first peak wavelength emitted from the first light emitting element and the second light emitting element, disposed above the first light emitting element and the second light emitting element, is light having a second peak wavelength different from the first peak wavelength. It has a wavelength conversion member that converts to
A light emitting device capable of outputting mixed light in which light having a first peak wavelength emitted from the first light emitting element and the second light emitting element and light having a second peak wavelength emitted from the wavelength conversion member are mixed. The light-emitting device according to claim 2,
The light emitting device in which the wavelength conversion member is directly provided on the mounting region, the first light emitting element, and the second light emitting element. The light-emitting device according to claim 1,
A light emitting device in which the first light emitting element is formed in a square shape. The light-emitting device according to claim 4,
The light emitting device, wherein the second light emitting element has a right triangle shape, a short side is substantially the same length as one side of the first light emitting element, and a hypotenuse is doubled. The light-emitting device according to claim 5,
The second light emitting element includes a hexagonal growth substrate, and a side surface including a short side and a side surface including a hypotenuse include the M plane of the growth substrate. The light-emitting device according to claim 4,
The light emitting device, wherein the second light emitting element has a right triangle shape, the short side is substantially the same length as one side of the first light emitting element, and the long side is twice as long. The light-emitting device according to claim 1,
In the circular outer edge, there are a plurality of areas where one or more outermost first light emitting elements arranged along the outer edge of the mounting area are arranged, and the area between the areas and along the outer edge. A light-emitting device in which one or more second light-emitting elements are arranged.

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