Method for producing optical member, optical member, and light-emitting device

Abstract

To provide a method for producing an optical member that is resistant to cracking during breaking, an optical member, and a light-emitting device including the optical member.SOLUTION: A method for producing an optical member comprises: a step of preparing a wavelength conversion member made of a polycrystalline body containing phosphor particles; a step of applying a first laser beam onto a first principal surface of the wavelength conversion member to form a groove; and a step of applying a second laser beam so as to overlap the groove to break the wavelength conversion member starting from the groove, wherein the energy density per unit length in the scanning direction of the second laser beam is greater than the energy density per unit length in the scanning direction of the first laser beam.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing an optical member, an optical member, and a light-emitting device. [Background technology]

[0002] A method has been proposed in which a ceramic substrate is scribed with a laser for the first time, then scribed with a laser for the second time so as to form a groove that is wider and shallower than the first laser scribe, and then broken along the dividing groove. In this method, the second laser scribe is performed with the same power as the first laser scribe but with a different focal length (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-276386 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a method for manufacturing an optical member that is less likely to crack when cut, an optical member, and a light emitting device using the optical member. [Means for solving the problem]

[0005] A manufacturing method for an optical member according to one embodiment of the present disclosure includes the steps of preparing a polycrystalline wavelength conversion member containing phosphor particles, irradiating a first main surface of the wavelength conversion member with a first laser light to form a groove, and irradiating a second laser light so as to overlap the groove and fracture the wavelength conversion member starting from the groove, wherein an energy density per unit length in a scanning direction of the second laser light is greater than an energy density per unit length in the scanning direction of the first laser light.

[0006] An optical element according to one embodiment of the present disclosure has a first main surface and a second main surface located opposite the first main surface, is a polycrystalline optical element containing phosphor particles, and has a convex portion arranged along the outer edge of the first main surface.

[0007] A light-emitting device according to one embodiment of the present disclosure comprises a light-emitting element, a light-guiding member arranged on the light-emitting element, and a polycrystalline optical member arranged on the light-guiding member and containing phosphor particles, the optical member having a convex portion arranged along the outer edge of a lower surface of the optical member, and the light-guiding member is arranged in a region surrounded by the convex portion when viewed from above. Effect of the Invention

[0008] According to an embodiment of the present disclosure, it is possible to provide a manufacturing method for an optical member that is less likely to crack when cut, an optical member, and a light emitting device using the optical member. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view illustrating an optical member according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] 1A to 1C are schematic diagrams illustrating a manufacturing process of the optical member according to the first embodiment (part 1). [Figure 4] 5A to 5C are schematic diagrams (part 2) illustrating the manufacturing process of the optical member according to the first embodiment. [Diagram 5] 5A to 5C are schematic diagrams (part 3) illustrating the manufacturing process of the optical member according to the first embodiment. [Figure 6] FIG. 13 is a diagram showing experimental results. [Figure 7] FIG. 11 is a perspective view illustrating a light emitting device according to a second embodiment. [Figure 8] 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7. [Figure 9] FIG. 9 is an enlarged view of part A in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a manufacturing method according to an embodiment of the present invention and an optical member obtained by the manufacturing method (hereinafter, sometimes referred to as "optical member according to an embodiment") will be described with reference to the drawings. In the following description, terms indicating specific directions or positions (for example, "upper", "lower", and other terms including these terms) will be used as necessary. However, the use of these terms is for the purpose of facilitating understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meaning of these terms. Furthermore, parts with the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or members.

[0011] In addition, the embodiments shown below are examples of a manufacturing method for an optical member for embodying the technical idea of ​​the present invention, and do not limit the present invention to the following. In addition, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended to be illustrative, and are not intended to limit the scope of the present invention, unless otherwise specified. In addition, the contents described in one embodiment can be applied to other embodiments and modified examples. In addition, the size and positional relationship of the members shown in the drawings may be exaggerated to clarify the explanation. In addition, in order to avoid the drawings becoming overly complicated, a schematic diagram in which some elements are omitted, or an end view showing only a cut surface may be used as a cross-sectional view.

[0012] <Optical member according to the first embodiment> FIG. 1 is a perspective view showing a schematic diagram of an optical member according to a first embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. In FIG. 1 and FIG. 2, the X-axis direction and the Y-axis direction are defined as being orthogonal to each other, and the direction perpendicular to the X-axis direction and the Y-axis direction is defined as the Z-axis direction. In other drawings, the X-axis direction, the Y-axis direction, and the Z-axis direction may be similarly shown. In addition, the direction in which the arrow points in the X-axis direction is indicated as the X-axis positive direction, and the direction opposite to the X-axis positive direction is indicated as the X-axis negative direction. The direction in which the arrow points in the Y-axis direction is indicated as the Y-axis positive direction, and the direction opposite to the Y-axis positive direction is indicated as the Y-axis negative direction. The direction in which the arrow points in the Z-axis direction is indicated as the Z-axis positive direction, and the direction opposite to the Z-axis positive direction is indicated as the Z-axis negative direction.

[0013] 1 and 2, the optical member 50 is approximately plate-shaped. The optical member 50 has a first main surface 50a, a second main surface 50b located on the opposite side to the first main surface 50a, and a side surface 50c. In the example of FIGS. 1 and 2, the optical member 50 further has a protrusion 50d arranged along the outer edge of the first main surface 50a.

[0014] In the optical member 50, the first main surface 50a and the second main surface 50b are flat surfaces. In the example of FIG. 1 and FIG. 2, the first main surface 50a and the second main surface 50b are square or rectangular in top view. The top view means viewing the object from the Z-axis direction. In the example of FIG. 1 and FIG. 2, the first main surface 50a and the second main surface 50b are parallel to the XY plane. Here, when describing "parallel," a difference of ±5 degrees is allowed. The same applies hereinafter. The thickness T of the optical member 50 is, for example, 50 μm or more and 200 μm or less. Here, the thickness T of the optical member 50 is the distance in the Z-axis direction between the first main surface 50a and the second main surface 50b, and does not include the height of the convex portion 50d.

[0015] The side surface 50c can include a first region 51 located on the first main surface 50a side of the optical member 50 and a second region 52 located on the second main surface 50b side of the optical member 50. In the example of Fig. 1 and Fig. 2, the first region 51 and the second region 52 are flat. The first region 51 and the second region 52 do not have to be flat, and may be, for example, at least partially curved. The second region 52 is connected to the second main surface 50b.

[0016] In the example of Fig. 1 and Fig. 2, the second region 52 is perpendicular to the second main surface 50b. The second region 52 is parallel to, for example, the XZ plane or the YZ plane. Here, when describing "perpendicular," a difference of ±5 degrees is allowed. The same applies hereinafter. The first region 51 is inclined toward the center of the optical member 50 with respect to the second region 52, and is located more inward than the second region 52 in a top view.

[0017] As described later, the optical member 50 is cut and divided into individual pieces by irradiation with laser light in the manufacturing process. Therefore, traces of the phosphor particles melted by the thermal energy of the laser light are exposed in the first region 51. Furthermore, cross sections of the phosphor particles are exposed in the second region 52. The cross sections of the phosphor particles are cut surfaces of the phosphor particles. The second region 52 has a larger surface roughness than the first region 51. The surface roughness of the first region 51 is, for example, 0.5 μm or more and 1.0 μm or less in arithmetic mean roughness Ra. In contrast, the surface roughness of the second region 52 is, for example, 2.0 μm or more and 3.0 μm or less in arithmetic mean roughness Ra.

[0018] In top view, the protrusion 50d is located inside the second region 52. For example, in cross-sectional view, the protrusion 50d has a shape that is widest on the first main surface 50a side and narrows as it moves away from the first main surface 50a in the positive direction of the Z axis. In cross-sectional view, the protrusion 50d may have a shape close to a triangle or other shapes. The top of the protrusion 50d may be pointed or may be rounded. The protrusion 50d has an inner surface and an outer surface, and the outer surface is a part of the first region 51 of the side surface 50c.

[0019] The height H of the protrusion 50d from the first major surface 50a is, for example, 1 μm or more and 5 μm or less. When viewed from a direction perpendicular to the first major surface 50a, the width W of the protrusion 50d is, for example, 30 μm or more and 80 μm or less. The depth D of the connection portion between the first region 51 and the second region 52 from the first major surface 50a is, for example, 3 μm or more and ½ the thickness T or less of the optical member 50. The inclination angle θ1 of the first region 51 with respect to the first major surface 50a is, for example, 5 deg or more and 70 deg or less.

[0020] The optical member 50 is a polycrystalline wavelength conversion member containing phosphor particles. The optical member 50 can convert incident light into light of a different wavelength and emit the converted light. The optical member 50 may emit a part of the incident light. The optical member 50 may convert all of the incident light into light of a different wavelength. In this case, the light incident on the optical member 50 is not emitted from the optical member 50.

[0021] The optical member 50 is a member having translucency. The optical member 50 can be used as a member constituting a light-emitting surface of a light-emitting device equipped with a light-emitting element. The optical member 50 converts light emitted from the light-emitting element into light of a different wavelength by making it incident on the first main surface 50a, and emits the converted light from the second main surface 50b, thereby adjusting the luminous chromaticity of the light-emitting device.

[0022] In this way, the optical member 50 can have the convex portions 50d arranged along the outer edge of the first main surface 50a. Therefore, when the optical member 50 is used in a light emitting device or the like, if the first main surface 50a side of the optical member 50 is fixed to another member by an adhesive resin, the adhesive resin can be arranged in the area surrounded by the convex portions 50d in a top view. That is, the uncured adhesive resin is blocked by the convex portions 50d and does not flow out to the outside of the convex portions 50d, so that after curing, the adhesive resin is arranged in the area surrounded by the convex portions 50d in a top view.

[0023] Furthermore, the side surface 50c of the optical member 50 can include a first region 51 and a second region 52 having a surface roughness larger than that of the first region 51. Therefore, when the optical member 50 is used in a light emitting device or the like and the optical member 50 is covered with a light reflective member such as a resin, the light reflective member comes into contact with the first region 51 of the optical member 50, thereby improving the adhesion between the optical member 50 and the light reflective member.

[0024] The optical member 50 may be a sintered body of a phosphor, a sintered body containing a phosphor and another inorganic material, or the like.

[0025] The phosphor contained in the optical member 50 is an yttrium-aluminum-garnet phosphor (e.g., (Y,Gd)3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA phosphors (e.g., Ca 10 (PO4)6Cl2:Eu), SAE phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSi4O 16 Cl2:Eu), silicate phosphors (e.g., (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu) or α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu) and other oxynitride phosphors, LSN phosphors (e.g., (La,Y)3Si6N 11 :Ce), BSESN phosphors (e.g., (Ba,Sr)2Si5N8:Eu), SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), nitride phosphors such as KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2(Si 1-x Al x )F 6-x:Mn where x satisfies 0 < x < 1. ) or a fluoride-based phosphor such as an MGF-based phosphor (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), a quantum dot having a perovskite structure (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3 where FA and MA represent formamidinium and methylammonium, respectively.), a II-VI group quantum dot (e.g., CdSe), a III-V group quantum dot (e.g., InP), or a quantum dot having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se)2) can be used.

[0026] As the inorganic material contained in the optical member 50, aluminum oxide, aluminum nitride, silicon oxide, yttrium oxide, zirconium oxide, magnesium oxide, or the like can be used.

[0027] <Manufacturing Method of Optical Member According to the First Embodiment> The manufacturing method of the optical member according to the first embodiment includes a step of preparing a wavelength conversion member which is a polycrystal containing phosphor particles, a step of irradiating a first main surface of the wavelength conversion member with a first laser beam to form a groove, and a step of irradiating the groove with a second laser beam so as to overlap the groove and cutting the wavelength conversion member starting from the groove. And the energy density per unit length in the scanning direction of the second laser beam is larger than the energy density per unit length in the scanning direction of the first laser beam.

[0028] Hereinafter, each manufacturing step of the manufacturing method of the optical member according to the first embodiment will be described with reference to the drawings.

[0029] Figs. 3 to 5 are schematic views for explaining the manufacturing process of the optical member according to the first embodiment. Specifically, Fig. 3 is a perspective view illustrating the manufacturing process of the optical member. Also, Figs. 4 and 5 are partial cross-sectional perspective views illustrating the manufacturing process of the optical member.

[0030] (Step of Preparing Wavelength Conversion Member) First, as shown in FIG. 3, a polycrystalline wavelength conversion member 50S is prepared, which has a first main surface 50a, a second main surface 50b opposite to the first main surface 50a, and a side surface 50sc connected to the first main surface 50a and the second main surface 50b, and contains phosphor particles. In the example of FIG. 3, the first main surface 50a and the second main surface 50b are parallel to the XY plane. The side surface 50sc is parallel to the XZ plane or the YZ plane. The Z-axis direction is the height direction (thickness direction) of the wavelength conversion member 50S. The thickness of the wavelength conversion member 50S to be prepared is, for example, 50 μm or more and 200 μm or less. The wavelength conversion member 50S may be prepared by manufacturing it, or may be prepared by receiving it from another person.

[0031] The wavelength conversion member 50S includes a plurality of regions 50R that become the optical members 50 after singulation. In the example of Fig. 3, the regions 50R are arranged two-dimensionally in a matrix shape in a top view of the wavelength conversion member 50S, with boundaries defined by a straight two-dot chain line extending in the X-axis direction and a straight two-dot chain line extending in the Y-axis direction. In the example of Fig. 3, the regions 50R are square in a top view of the wavelength conversion member 50S. Note that the two-dot chain lines are virtual lines indicating boundaries and cannot actually be seen.

[0032] (Groove forming process) Next, as shown in FIG. 4, the first laser light La is irradiated onto the first main surface 50a of the wavelength conversion member 50S to form the grooves 50g.

[0033] Specifically, first, as shown in the upper arrow of Fig. 4, the first laser light La is irradiated from a direction substantially perpendicular to the first main surface 50a of the wavelength conversion member 50S. The position where the first laser light La is condensed is near the first main surface 50a of the wavelength conversion member 50S. The peak wavelength of the first laser light La is, for example, in the range of 350 nm or more and 360 nm or less. For example, a UV-YAG laser can be used to irradiate the first laser light La in such a peak wavelength range.

[0034] The first laser light La is irradiated while scanning, for example, a two-dot chain line indicating the boundary of the region 50R extending in the Y-axis direction in the positive direction of the Y-axis. As a result, as shown below the arrow in FIG. 4, a groove 50g is formed linearly along the Y-axis direction at a position overlapping with the region R in a top view. The groove 50g is formed, for example, in a V-shape in a cross-sectional view. The bottom of the groove 50g may be pointed or may be rounded. The depth of the groove 50g from the first main surface 50a may be, for example, 3 μm or more and may be ½ or less of the thickness of the wavelength conversion member 50S. If the thickness of the wavelength conversion member 50S is 200 μm, the depth of the groove 50g from the first main surface 50a may be, for example, 40 μm. In addition, the angle θ2 of the V shape of the groove 50g in a cross-sectional view may be, for example, 40 deg or more and 170 deg or less.

[0035] The energy density per unit length in the scanning direction of the first laser beam La is 2.6×10 3 (J / (cm 2 Larger than 8×10 mm 4 (J / (cm 2 In this manner, by setting the energy density per unit length in the scanning direction of the first laser beam La to a relatively small value, grooves 50g that do not penetrate wavelength conversion member 50S and that do not cause shattering or cracking can be formed.

[0036] In addition, when there are multiple (here, five) dotted lines indicating the boundaries of region 50R along the Y-axis direction as shown in FIG. 3, the first laser light La is irradiated sequentially along those lines to form grooves 50g at each irradiated position.

[0037] Next, the first laser light La is irradiated along the two-dot chain lines that indicate the boundaries of the region 50R extending in the X-axis direction. As a result, grooves 50g are formed linearly along the X-axis direction at positions that overlap with the region R in top view. If there are multiple two-dot chain lines (three in this case) that indicate the boundaries of the region 50R along the X-axis direction as shown in Fig. 3, the first laser light La is irradiated along those lines to form grooves 50g at each irradiation position.

[0038] As a result of the above, grooves 50g opening to the first main surface 50a side are formed in a lattice pattern in the wavelength conversion member 50S at positions overlapping with the boundary lines of the regions 50R in a top view of the wavelength conversion member 50S.

[0039] 4, protrusions 50d protruding from the first main surface 50a may be formed on both outer sides of the groove 50g. The protrusions 50d can be formed by melting a part of the wavelength conversion member 50S by thermal energy generated by irradiation with the first laser light La. The height of the protrusions 50d from the first main surface 50a can be, for example, 1 μm or more and 5 μm or less. Also, the width of the protrusions 50d when viewed from a direction perpendicular to the first main surface 50a can be 30 μm or more and 80 μm or less.

[0040] (Step of breaking the wavelength conversion member) Next, the second laser light Lb is irradiated so as to overlap the grooves 50g, and the wavelength conversion member 50S is fractured starting from the grooves 50g.

[0041] Specifically, first, as shown in the upper side of the arrow in FIG. 5, the second laser light Lb is irradiated from a direction substantially perpendicular to the first main surface 50a of the wavelength conversion member 50S. The position in the X-axis direction where the second laser light Lb is condensed is inside the groove 50g. The position in the Z-axis direction where the second laser light Lb is condensed may be the same as the position in the Z-axis direction where the first laser light Lb is condensed (i.e., near the first main surface 50a), or may be a position in the groove 50g that is deeper in the Z-axis negative direction than the first main surface 50a. The peak wavelength of the second laser light Lb is, for example, in the range of 350 nm or more and 360 nm or less, similar to the peak wavelength of the first laser light La. The energy density per unit length in the scanning direction of the second laser light Lb is greater than the energy density per unit length in the scanning direction of the first laser light La. The second laser light La is irradiated while scanning in the Y-axis positive direction so as to overlap with the groove 50g extending in the Y-axis direction.

[0042] By irradiating the second laser beam Lb, as shown below the arrow in Fig. 5, thermal stress S is generated in the tensile direction, and the wavelength conversion member 50S is warped in the direction of the arrow R. This causes the wavelength conversion member 50S to be broken starting from the groove 50g. Note that the thermal stress S becomes larger in a position closer to the deepest part of the groove 50g.

[0043] When there are multiple grooves 50g along the Y-axis direction, the second laser light Lb is irradiated sequentially so as to overlap the grooves 50g, and the wavelength conversion member 50S is fractured along the Y-axis direction. Next, the second laser light Lb is irradiated sequentially so as to overlap each groove 50g arranged along the X-axis direction, and the wavelength conversion member 50S is fractured along the X-axis direction. This separates the wavelength conversion member 50S, and multiple optical members 50 shown in FIG. 1 and FIG. 2 are produced.

[0044] The side surface 50c of the optical member 50 obtained by cleaving can include a first region 51 located on the first main surface 50a side of the optical member 50 and a second region 52 located on the second main surface 50b side of the optical member 50. The first region 51 is a region where traces of the phosphor particles melted by the thermal energy of the laser light are exposed. The second region 52 is a cleaved surface, and is a region where cross sections of the phosphor particles are exposed. The surface roughness of the first region 51 and the second region 52 is as described above.

[0045] In this manner, in the manufacturing method of the optical member 50, the first main surface 50a of the wavelength conversion member 50S is irradiated with the first laser light La to form the groove 50g. Then, the second laser light Lb, which has a higher energy density per unit length in the scanning direction than the first laser light La, is irradiated so as to overlap with the groove, and the wavelength conversion member 50S is cleaved starting from the groove 50g. In this method, the cleaving direction can be controlled by the thermal stress caused by the irradiation of the second laser light Lb, which has a higher energy density per unit length in the scanning direction. Therefore, it is possible to realize a manufacturing method of the optical member 50 in which unintended cracks are less likely to occur during cleaving, compared to the conventional cleaving method using laser ablation. In other words, it is possible to realize thermal cleaving with reduced crack generation around the cleaving portion.

[0046] In addition, the time required for cutting can be shortened compared to conventional cutting methods using laser ablation, and contamination due to adhesion of dust such as fumes and burnout on the first main surface 50a and the second main surface 50b caused by irradiation with laser light can be reduced compared to conventional cutting methods using laser ablation.

[0047] In addition, in the conventional cutting method using laser ablation, traces of melted phosphor particles are exposed over the entire cut surface.

[0048] In the manufacturing method of the optical member 50, the energy density per unit length in the scanning direction of the second laser light Lb is 4×10 4 (J / (cm 2 · Larger than 4 × 10 mm 5 (J / (cm 2 The energy density is preferably 4×10 4 (J / (cm 2 By making the energy density larger than 4×10 20 mm, it becomes possible to cut the wavelength conversion member 50S and also possible to reduce the risk of cracks occurring during cutting. 5 (J / (cm 2 By setting the thickness to be equal to or less than 1.0 mm, the risk of wavelength conversion member 50S being crushed can be reduced.

[0049] The energy density per unit length in the scanning direction of the first laser beam La is 8×10 3 (J / (cm 2 Larger than 8×10 mm 4 (J / (cm 2 .mm), and the energy density per unit length in the scanning direction of the second laser light Lb is less than 4×10 4 (J / (cm 2 · Larger than 4 × 10 mm 5 (J / (cm 2.·mm) or less. Under such conditions, it is possible to cut wavelength conversion member 50S, and the risk of cracks occurring during cutting can be further reduced. Also, the risk of wavelength conversion member 50S being crushed can be further reduced.

[0050] Moreover, it is preferable that the scanning speed of the second laser light Lb is slower than that of the first laser light La. As a result, even if the output of the second laser light Lb is the same as that of the first laser light La, the energy density per unit length in the scanning direction of the second laser light Lb can be easily made larger than that of the first laser light La. Also, adjusting the energy density by the scanning speed rather than the output of the laser light can shorten the processing time. Note that, the processing time can be shortened most by setting both the output of the second laser light Lb and the output of the first laser light La to their maximum and adjusting the energy density by the scanning speed.

[0051] The scanning speed of the second laser light Lb may be the same as the scanning speed of the first laser light La. In this case, by making the output of the second laser light Lb larger than the output of the first laser light La, the energy density per unit length in the scanning direction of the second laser light Lb can be made larger than the energy density per unit length in the scanning direction of the first laser light La.

[0052] Fig. 6 is a diagram showing the results of an experiment. In the experiment, a wavelength conversion member having a thickness of 200 µm was prepared. Then, the condition of the energy density per unit length in the scanning direction of the first laser beam La and the second laser beam La was changed, and the wavelength conversion member was cleaved by the method described with reference to Figs. 3 to 5 to confirm the cleavability.

[0053] 6, "energy density of first laser light La" indicates the energy density per unit length in the scanning direction of the first laser light La. Similarly, "energy density of second laser light Lb" indicates the energy density per unit length in the scanning direction of the second laser light Lb.

[0054] In addition, in FIG. 6, "x" indicates that it was not possible to break or that the wavelength conversion member was crushed. "△" indicates that the groove was too deep and was not suitable for the breaking method shown in FIG. 3 to FIG. 5. "◯" indicates that under the same conditions, it was possible to break 2 / 3 times without cracking, and it was possible to break 1 / 3 times, but cracks occurred at a level acceptable for practical use. "◎" indicates that under the same conditions, it was possible to break 3 / 3 times without cracking.

[0055] As shown in Fig. 6, when the second laser light La was irradiated without irradiating the first laser light La, the result was "X" regardless of the value of the energy density per unit length in the scanning direction of the second laser light La. In other words, even if the second laser light Lb was irradiated without forming a groove in the wavelength conversion member, the wavelength conversion member could not be cleaved. From this result, it is considered that the groove formed by irradiating the first laser light La controls the tensile stress of the thermal stress S caused by the second laser light Lb and promotes cleavage from the deepest part of the groove 50g in the negative direction of the Z axis.

[0056] In addition, the energy density per unit length in the scanning direction of the first laser beam La is 8×10 4 (J / (cm 2 In the case of (a) (1.0 mm), the result was either “×” or “△” regardless of the value of the energy density per unit length in the scanning direction of the second laser beam La.

[0057] In addition, the energy density per unit length in the scanning direction of the first laser beam La is 4×10 4 (J / (cm 2 In the case of the second laser beam La having an energy density of 4×10 5 (J / (cm 2 ·mm)), the result is "Yes" and 8 × 10 4 (J / (cm 2 .·mm), the result was “◎”. If the energy density per unit length in the scanning direction of the second laser beam La was any other value, the result was “×”.

[0058] In addition, the energy density per unit length in the scanning direction of the first laser beam La is 8×10 3 (J / (cm 2 In the case of the second laser beam La having an energy density of 4×10 5 (J / (cm 2 .mm), the result was “good.” If the energy density per unit length in the scanning direction of the second laser beam La was any other value, the result was “bad.”

[0059] In addition, the energy density per unit length in the scanning direction of the first laser beam La is 4×10 3 (J / (cm 2 In the case of the second laser beam La having an energy density of 4×10 5 (J / (cm 2 .mm), the result was “good.” If the energy density per unit length in the scanning direction of the second laser beam La was any other value, the result was “bad.”

[0060] In addition, the energy density per unit length in the scanning direction of the first laser beam La is 2.6×10 3 (J / (cm 2 In the case of (a) (1.0 mm), the result was “×” regardless of the value of the energy density per unit length in the scanning direction of the second laser beam La.

[0061] From the above, the energy density per unit length in the scanning direction of the first laser beam La is 2.6×10 3 (J / (cm 2 Larger than 8×10 mm 4 (J / (cm 2 In addition, it is preferable that the energy density per unit length in the scanning direction of the second laser beam Lb is smaller than 4×10 4 (J / (cm 2 · Larger than 4 × 10 mm 5 (J / (cm 2Under such conditions, the wavelength conversion member will not be broken or shattered, and the risk of cracks occurring during breaking can be reduced.

[0062] In the first embodiment, an example of manufacturing a rectangular optical member 50 by cutting has been shown, but the shape of an optical member that can be manufactured by cutting is not limited to a rectangle. For example, a circular optical member can be manufactured by the cutting method according to the first embodiment. A circular optical member formed from a polycrystalline material containing phosphor particles can be used, for example, as a phosphor wheel mounted on a projector.

[0063] Second Embodiment In the second embodiment, an example of a light emitting device having the optical member according to the first embodiment will be described.

[0064] Fig. 7 is a perspective view showing a schematic diagram of a light emitting device according to a second embodiment. Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 7. Fig. 8 shows a cross section of the light emitting device 1 cut along a plane perpendicular to the upper surface of the light emitting element 20. Fig. 9 is an enlarged view of part A in Fig. 8.

[0065] 7 to 9, the light emitting device 1 includes a wiring board 10, a light emitting element 20, a protective element 30, a light guiding member 40, an optical member 50, and a light reflective member 60. The light emitting device 1 may not include the wiring board 10, the protective element 30, and the light reflective member 60.

[0066] In the light emitting device 1, the light emitting element 20 is disposed on the wiring board 10. The light emitting element 20 has an upper surface 20a, a plurality of side surfaces 20c continuous with the upper surface 20a, and a lower surface 20b opposite to the upper surface 20a. The plurality of side surfaces 20c are continuous with the upper surface 20a and the lower surface 20b. In other words, the plurality of side surfaces 20c each have an outer edge continuous with the outer edge of the upper surface 20a and the outer edge of the lower surface 20b. In the light emitting element 20, light is emitted from the upper surface 20a, the lower surface 20b, and the side surfaces 20c. Furthermore, in the light emitting device 1, a protective element 30 may be disposed on the wiring board 10.

[0067] The light emitting element 20 has a substantially rectangular upper surface 20a. For example, the light emitting element 20 has an external shape of a substantially rectangular parallelepiped or a substantially quadrangular pyramid. In this case, the upper surface 20a and the lower surface 20b of the light emitting element 20 are substantially rectangular, and the light emitting element 20 has four substantially rectangular or substantially trapezoidal side surfaces 20c. The shape of the upper surface 20a of the light emitting element 20 may be a polygon such as a triangle or a hexagon. The light emitting element 20 may also have an external shape of a columnar body or a pyramid body with a polygonal upper surface.

[0068] The light guide member 40 is disposed on the light emitting element 20. The light guide member 40 continuously covers the upper surface 20a of the light emitting element 20 and a plurality of side surfaces 20c connected to the upper surface 20a. Specifically, the light guide member 40 covers the entire upper surface 20a of the light emitting element 20 and at least a part of the upper end side of each side surface 20c (i.e., the outer edge side connected to the upper surface 20a). The light guide member 40 has a side surface 40c that contacts the side surface 20c of the light emitting element 20 and the lower surface of the optical member 50. The light guide member 40 can be formed by spreading an uncured adhesive resin that bonds the optical member 50 and the light emitting element 20 onto the side surface 20c of the light emitting element 20 and then curing the resin.

[0069] The light guide member 40 preferably covers a larger area of ​​each side surface 20c of the light emitting element 20, and more preferably covers substantially all of each side surface 20c. That is, the side surface 40c of the light guide member 40 preferably contacts the side surface 20c at a position close to the lower end side of each side surface 20c of the light emitting element 20 (i.e., the side connected to the lower surface 20b), and more preferably contacts the lower end of each side surface 20c. Specifically, it is preferable that the light guide member 40 covers an area of ​​75% to 100% in the height direction from the upper end side of each side surface 20c of the light emitting element 20, and more preferably covers an area of ​​90% to 100% in the height direction.

[0070] The optical member 50 is disposed on the light-guiding member 40. As described in the first embodiment, the optical member 50 is a polycrystalline wavelength conversion member containing phosphor particles. In this embodiment, the first main surface 50a of the optical member 50 is the lower surface, and the second main surface 50b is the upper surface. The optical member 50 has a convex portion 50d disposed along the outer edge of the first main surface 50a of the optical member 50. When viewed from above, the light-guiding member 40 is disposed in a region surrounded by the convex portion 50d.

[0071] 9, the side surface 50c of the optical member 50 may include a first region 51 located on the lower surface side of the optical member 50 and a second region 52 located on the upper surface side of the optical member 50. Details of the first region 51 and the second region 52 are as described in the first embodiment. In a top view, the convex portion 50d is located inside the second region 52.

[0072] The second main surface 50b of the optical member 50 constitutes a part of the upper surface of the light emitting device 1 as a light extraction surface of the light emitting device 1. The optical member 50 is disposed on the light emitting element 20 such that the first main surface 50a of the optical member 50 faces the upper surface 20a of the light emitting element 20 via the light guiding member 40 disposed on the upper surface 20a of the light emitting element 20. The optical member 50 is disposed such that the first main surface 50a of the optical member 50 is substantially parallel to the upper surface 20a of the light emitting element 20. It is preferable that the shape of the first main surface 50a of the optical member 50 is similar to the shape of the upper surface 20a of the light emitting element. For example, when the upper surface 20a of the light emitting element is rectangular, it is preferable that the first main surface 50a of the optical member 50 is also rectangular.

[0073] The first main surface 50a of the optical member 50 is preferably larger in area than the upper surface 20a of the light emitting element 20. In addition, the optical member 50 is preferably arranged so that the first main surface 50a of the optical member 50 encloses the light emitting element 20 in a top view. In addition, in the light emitting device 1, the light guiding member 40 interposed between the first main surface 50a of the optical member 50 and the upper surface 20a of the light emitting element 20 preferably covers the first main surface 50a of the optical member 50 that does not overlap with the upper surface 20a of the light emitting element 20 in a top view. Furthermore, in the light emitting device 1, the light guiding member 40 is preferably arranged so as to reach the outer edge of the first main surface 50a of the optical member 50, and it is more preferable that the entire first main surface 50a is covered with the light guiding member 40. This allows more of the light emitted from the light emitting element 20 to be incident from the first main surface 50a of the optical member 50 via the light guiding member 40.

[0074] The light reflective member 60 is disposed on the wiring board 10, exposes the second main surface 50b, which is the upper surface of the optical member 50, and covers the side surface 50c of the optical member 50 and the side surface 20c of the light emitting element 20. The light reflective member 60 may directly cover the side surface 20c of the light emitting element 20, or may cover it via another member such as the light guiding member 40. Furthermore, when the light emitting device 1 has a protective element 30, the light reflective member 60 preferably covers the upper surface, lower surface, and side surface of the protective element 30. Furthermore, the light reflective member 60 may cover the side surface 20c of the light emitting element 20 exposed from the light guiding member 40 and the lower surface 20b of the light emitting element 20.

[0075] By covering the side surface 40c of the light-guiding member 40 with the light-reflective member 60, the light is emitted from the side surface 20c of the light-emitting element 20 and transmitted through the light-guiding member 40, and is reflected by the light-reflective member 60. Furthermore, by covering the lower surface 20b of the light-emitting element 20 with the light-reflective member 60, the light proceeding downward from the light-emitting element 20 is reflected by the light-reflective member 60. As a result, the light extraction efficiency of the light-emitting device 1 can be improved.

[0076] The light reflective member 60 may be composed of a single member or a plurality of members. In the example shown in Fig. 7 to Fig. 9, the light reflective member 60 is composed of a first light reflective member 61 and a second light reflective member 62. The first light reflective member 61 is disposed on the wiring board 10, for example, and covers the lower surface 20b of the light emitting element 20 and at least a part of the side surface 40c of the light guide member 40. In addition, when the light emitting device 1 has a protective element 30, the first light reflective member 61 covers, for example, the lower surface and at least a part of the side surface of the protective element 30.

[0077] The second light reflective member 62 is, for example, disposed on the first light reflective member 61, and covers the side surface 50c of the optical member 50. In addition, in the case where the light emitting device 1 has a protective element 30, the second light reflective member 62 covers, for example, an upper surface of the protective element 30. The second light reflective member 62 may cover a part of the side surface of the optical member 50 and a part of the side surface of the protective element 30.

[0078] The side surface of the second light reflective member 62, together with the side surface of the base material 11 of the wiring board 10, constitutes the side surface of the light emitting device 1. The side surface of the second light reflective member 62 and the side surface of the base material 11 may be, for example, flush with each other. Furthermore, the upper surface of the second light reflective member 62 and the second main surface 50b of the optical member 50 may be, for example, flush with each other.

[0079] Thus, in the light emitting device 1, the optical member 50 has the convex portion 50d arranged along the outer edge of the first main surface 50a of the optical member 50. Then, in the light emitting device 1, when the optical member 50 is arranged on the light emitting element 20, an uncured adhesive resin that becomes the light guiding member 40 when cured is arranged between the optical member 50 and the light emitting element 20, and the adhesive resin is cured. Since the uncured adhesive resin is blocked by the convex portion 50d, after curing, the light guiding member 40 is arranged in the area surrounded by the convex portion 50d in a top view. That is, in the light emitting device 1, the risk that the light guiding member 40 flows out to the side surface 50c of the optical member 50 can be reduced.

[0080] Furthermore, if the light guide member 40 flows out toward the side surface 50c of the optical member 50, a gap is generated between the optical member 50 and the light reflective member 60, and light from the light emitting element 20 may leak through the gap between the optical member 50 and the light reflective member 60. However, in the light emitting device 1, the light guide member 40 does not easily flow out toward the side surface 50c of the optical member 50, so a gap is unlikely to be generated between the optical member 50 and the light reflective member 60. That is, in the light emitting device 1, the risk of light from the light emitting element 20 leaking through the gap between the optical member 50 and the light reflective member 60 can be reduced.

[0081] In the light emitting device 1, the side surface 50c of the optical member 50 may include a first region 51 and a second region 52, and it is preferable that the second region 52 has a surface roughness larger than that of the first region 51. The first region 51, which is closer to the convex portion 50d, has a small surface roughness and is easy to repel the resin constituting the light guide member 40, so that the risk of the light guide member 40 flowing out to the side surface 50c of the optical member 50 can be reduced. Such an effect is easily achieved by the surface roughness of the first region 51 being 0.5 μm or more and 1.0 μm or less in arithmetic mean roughness Ra. In addition, by positioning the convex portion 50d on the inside of the second region 52 in a top view, the risk of the light guide member 40 flowing out to the side surface 50c of the optical member 50 can be further reduced.

[0082] On the other hand, since the second region 52 has a larger surface roughness than the first region 51, when the light reflective member 60 comes into contact with the second region 52 of the optical member 50, the adhesion between the optical member 50 and the light reflective member 60 can be improved by an anchor effect. When the surface roughness of the second region 52 is 2.0 μm or more and 3.0 μm or less in arithmetic mean roughness Ra, this effect is easily produced. Furthermore, by improving the adhesion between the optical member 50 and the light reflective member 60, in the light emitting device 1, the risk of light from the light emitting element 20 leaking through a gap between the optical member 50 and the light reflective member 60 can be further reduced.

[0083] Furthermore, in the light emitting device 1, the first region 51 constituting the side surface 50c of the optical member 50 is inclined with respect to the second region 52 and is located more inward than the second region 52 in a top view. This allows the light incident on the optical member 50 to be reflected by the first region 51 in the direction of the second main surface 50b, thereby improving the light extraction efficiency of the light emitting device 1.

[0084] Each element constituting the light emitting device 1 according to the embodiment will be described in detail below.

[0085] [Wiring board 10] The wiring board 10 is a member on which the light emitting element 20 is disposed. The wiring board 10 includes wiring for supplying power to the light emitting element from the outside and a base material 11 that supports the wiring. As an example, the wiring board 10 has an upper surface wiring 12 disposed on the upper surface on which the light emitting element 20 is disposed, and a lower surface wiring 13 disposed on the lower surface opposite to the upper surface. The base material 11 is, for example, substantially rectangular parallelepiped in shape. For the base material 11, it is preferable to use a material that is an insulating material and is difficult to transmit light emitted from the light emitting element 20 and external light. Examples of materials for the base material 11 include ceramics such as aluminum oxide, aluminum nitride, silicon nitride, and mullite, resins such as epoxy resin, silicone resin, modified epoxy resin, urethane resin, phenolic resin, polyimide resin, BT resin, and polyphthalamide, semiconductors such as silicon, and metals such as copper and aluminum, and composite materials thereof. Among these, ceramics having excellent heat dissipation properties can be suitably used as the material for the base material 11.

[0086] The upper wiring 12 includes wiring electrically connected to the light emitting element 20 and wiring electrically connected to the protective element 30. The lower wiring 13 includes an external connection terminal electrically connected to an external power source. For the upper wiring 12 and the lower wiring 13, for example, metals such as iron, copper, nickel, aluminum, gold, silver, platinum, titanium, tungsten, and palladium, or alloys containing at least one of these metals, can be used. Furthermore, the wiring board 10 may include relay wiring inside and / or on the side of the base material 11 for connecting the upper wiring 12 and the lower wiring 13.

[0087] The wiring board 10 does not necessarily have to have the bottom wiring 13. In this case, an external connection terminal that is electrically connected to an external power source may be disposed on the top or side surface.

[0088] The wiring board 10 may have a recess on its upper surface, and the light emitting device 1 may have a structure in which the light emitting element 20 is disposed at the bottom of the recess of the wiring board 10. The light emitting device 1 may also have a structure without the wiring board 10. For example, the light emitting device may have a structure in which a metal member exposed from a light reflective member 60 covering the lower surface 20b of the light emitting element 20 is provided as an electrode of the light emitting device 1.

[0089] (Light emitting element 20) The light emitting element 20 can be suitably a semiconductor light emitting element such as a light emitting diode (LED) chip or a semiconductor laser (LD) chip. The shape, size, etc. of the light emitting element 20 can be selected arbitrarily. The light emitting element 20 has, for example, a plurality of electrodes 25 on the lower surface 20b. The light emitting element 20 is disposed on the wiring board 10. The light emitting element 20 is flip-chip mounted on the wiring board 10, for example, with the lower surface 20b having the electrodes 25 facing the wiring board 10. The plurality of electrodes 25 of the light emitting element 20 are electrically connected to the upper surface wiring 12. The plurality of electrodes 25 of the light emitting element 20 and the upper surface wiring 12 can be connected using a known member such as eutectic solder, conductive paste, or bump.

[0090] The light emitting element 20 includes, for example, a semiconductor structure and a support substrate that supports the semiconductor structure. The semiconductor structure includes an n-side semiconductor layer, a p-side semiconductor layer, and an active layer sandwiched between the n-side semiconductor layer and the p-side semiconductor layer. The active layer may have a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including multiple well layers. The semiconductor structure includes multiple semiconductor layers made of nitride semiconductors. The nitride semiconductors include In x Al y Ga 1-x-y The term "active layer" includes semiconductors of all compositions in which the composition ratios x and y are changed within the respective ranges in the chemical formula N (0≦x, 0≦y, x+y≦1). The emission peak wavelength of the active layer can be appropriately selected depending on the purpose. The active layer is configured to be capable of emitting, for example, visible light or ultraviolet light.

[0091] The light emitting element 20 may have one semiconductor structure on one support substrate, or may have multiple semiconductor laminates on one support substrate. Furthermore, one semiconductor structure may have only one light emitting layer, or may have multiple light emitting layers. The structure of the semiconductor structure having multiple light emitting layers may be a structure including multiple active layers between one n-side semiconductor layer and one p-side semiconductor layer, or a structure including an n-side semiconductor layer, an active layer, and a p-side semiconductor layer in that order may be repeated multiple times.

[0092] In the light emitting element 20, a plurality of electrodes 25 are disposed on the semiconductor structure. The electrodes 25 include an n-electrode connected to the n-side semiconductor layer and a p-electrode connected to the p-side semiconductor layer. The p-electrode and the n-electrode may be disposed on different surfaces of the semiconductor laminate, or may be disposed on the same surface. Here, the plurality of electrodes 25 including the p-electrode and the n-electrode are disposed on the same surface of the semiconductor structure, and the side on which the plurality of electrodes 25 are disposed constitutes the lower surface 20b of the light emitting element 20, and the surface of the support substrate opposite to the surface on which the semiconductor structure is disposed constitutes the upper surface 20a of the light emitting element 20. Examples of the support substrate include insulating substrates such as sapphire and spinel (MgAl2O4), and nitride-based semiconductor substrates such as gallium nitride. Note that in order to extract the light emitted from the active layer through the support substrate, it is preferable to use a material having translucency for the support substrate. Note that the light emitting element 20 may be configured without a support substrate. In this case, the surface of the semiconductor structure opposite to the surface on which the electrodes are disposed constitutes the upper surface 20a of the light emitting element 20.

[0093] (Protection element 30) The light emitting device 1 may include a protective element 30. The protective element 30 is a member for improving electrostatic breakdown voltage. The protective element 30 is, for example, a Zener diode. The protective element 30 is disposed on the wiring board 10.

[0094] (Light guiding member 40) The light guide member 40 is a member that guides the light emitted from the light emitting element 20 to the optical member 50. By covering the side surface of the light emitting element 20 with the light guide member 40, the light emitted from the side surface of the light emitting element 20 can be easily guided to the optical member 50, and the light extraction efficiency of the light emitting device 1 can be improved. In addition, the light guide member 40 can be used as an adhesive member that bonds the light emitting element 20 and the optical member 50 together.

[0095] The light guide member 40 is disposed so as to cover the upper surface 20a and each side surface 20c of the light emitting element 20. For example, a light-transmitting resin can be used as the light guide member 40. For example, a thermosetting resin such as an epoxy resin, a modified epoxy resin, a silicone resin, or a modified silicone resin can be used as the light-transmitting resin. Among them, a silicone resin having high heat resistance is preferably used. The light guide member 40 may contain a light diffusing material or a phosphor in the light-transmitting resin. The light guide member 40 may also be a light-transmitting inorganic material. For example, a light-transmitting inorganic material can be used as the light-transmitting inorganic material. For example, a material obtained by converting polysilazane into silicon oxide by heating can be used as the light-transmitting inorganic material.

[0096] (Light reflective member 60) The light reflective member 60 preferably has a light blocking property, specifically, preferably has a light reflecting property and / or a light absorbing property. In particular, it preferably contains a material that can suitably reflect the light emitted from the light emitting element 20. For example, it preferably has a reflectance of 60% or more with respect to the light emitted from the light emitting element 20, and more preferably has a reflectance of 70% or more, 80% or more, or 90% or more.

[0097] The light reflecting member 60 is preferably made of an insulating material. The light reflecting member 60 is, for example, a member in which particles of a light reflecting substance are contained in a translucent resin. Examples of the resin used for the light reflecting member 60 include resins or hybrid resins containing one or more of silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, urea resin, acrylic resin, phenol resin, bismaleimide triazine resin, and polyphthalamide resin. Among these, it is preferable to use silicone resin, which is excellent in light resistance, heat resistance, and electrical insulation and has flexibility. Examples of the light reflecting substance include titanium oxide, silicon oxide, aluminum oxide, zirconium oxide, magnesium oxide, potassium titanate, barium titanate, zinc oxide, silicon nitride, aluminum nitride, boron nitride, calcium carbonate, calcium hydroxide, calcium silicate, and combinations thereof. Among these, it is preferable to use titanium oxide, which has a relatively high refractive index, from the viewpoint of light reflection.

[0098] As described above, the light reflective member 60 may be composed of a first light reflective member 61 and a second light reflective member 62. In this case, each of the first light reflective member 61 and the second light reflective member 62 can be formed using a material selected from the above-mentioned materials exemplified as the material of the light reflective member 60. By configuring the light reflective member 60 from the first light reflective member 61 and the second light reflective member 62, it becomes possible to use a material with high mechanical strength for the second light reflective member 62 constituting the outer surface of the light emitting device 1, or to use a material with low elasticity and low linear expansion for the first light reflective member 61 covering the lower surface 20b of the light emitting element 20, thereby alleviating the stress of resin expansion.

[0099] (Operation of light emitting device 1) In the light emitting device 1, when a current is supplied from an external power source to the light emitting element 20, the light emitting element 20 emits light. Of the light emitted by the light emitting element 20, the light traveling upward (i.e., toward the lower surface of the optical member) is extracted to the outside of the light emitting device 1 via the light guiding member 40 and the optical member 50. Of the light emitted by the light emitting element 20, the light traveling downward is reflected by the light reflective member 60 and the wiring board 10, and is extracted to the outside of the light emitting device 1 via the light guiding member 40 and the optical member 50. Of the light emitted by the light emitting element 20, the light traveling in the lateral direction is reflected at the interface between the side surface 20c of the light guiding member 40 and the light reflective member 60, and is extracted to the outside of the light emitting device 1 via the light guiding member 40 and the optical member 50.

[0100] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0101] In addition to the above-described embodiment, the following supplementary notes are further disclosed. (Appendix 1) preparing a polycrystalline wavelength conversion member containing phosphor particles; irradiating a first main surface of the wavelength conversion member with a first laser light to form a groove; irradiating the second laser light so as to overlap the groove, and fracturing the wavelength conversion member starting from the groove; Equipped with A method for manufacturing an optical member, wherein an energy density per unit length in the scanning direction of the second laser light is greater than an energy density per unit length in the scanning direction of the first laser light. (Appendix 2) The energy density per unit length in the scanning direction of the first laser light is 2.6×10 3 (J / (cm 2 Larger than 8×10 mm 4 (J / (cm 2 2. The method for producing an optical member according to claim 1, wherein the thickness of the optical member is smaller than or equal to 1 mm. (Appendix 3) The energy density per unit length in the scanning direction of the second laser light is 4×10 4 (J / (cm 2 · Larger than 4 × 10 mm 5 (J / (cm 2 2. The method for producing an optical member according to claim 1, wherein the thickness of the optical member is less than or equal to 1. (Appendix 4) The energy density per unit length in the scanning direction of the first laser light is 8×10 3 (J / (cm 2 Larger than 8×10 mm 4 (J / (cm 2 and the energy density per unit length in the scanning direction of the second laser light is less than 4×10 4 (J / (cm 2 · Larger than 4 × 10 mm 5 (J / (cm 2 2. The method for producing an optical member according to claim 1, wherein the thickness of the optical member is less than or equal to 1. (Appendix 5) 5. The method for producing an optical member according to claim 1, wherein a scanning speed of the second laser light is slower than a scanning speed of the first laser light. (Appendix 6) 6. The method for producing an optical member according to any one of claims 1 to 5, wherein the peak wavelengths of the first laser beam and the second laser beam are each within a range of 350 nm or more and 360 nm or less. (Appendix 7) 7. The method for manufacturing an optical member according to any one of claims 1 to 6, wherein the depth of the groove from the first main surface is 3 μm or more and is ½ or less of a thickness of the wavelength conversion member. (Appendix 8) 8. The method for producing an optical member according to claim 1, wherein in the step of forming the groove, a convex portion is formed outside the groove. (Appendix 9) 9. The method for producing an optical member according to claim 8, wherein the height of the convex portion from the first main surface is 1 μm or more and 5 μm or less. (Appendix 10) 10. The method for producing an optical member according to claim 8, wherein the width of the convex portion is 30 μm or more and 80 μm or less when viewed from a direction perpendicular to the first main surface. (Appendix 11) A light-emitting element; a light guiding member disposed on the light emitting element; a polycrystalline optical member that is disposed on the light guide member and that contains phosphor particles; the optical member has a convex portion disposed along an outer edge of a lower surface of the optical member, The light guiding member is disposed in a region surrounded by the protrusion when viewed from above. (Appendix 12) the side surface of the optical member includes a first region located on a lower surface side of the optical member and a second region located on an upper surface side of the optical member, 12. The light emitting device according to claim 11, wherein the convex portion is located more inward than the second region in a top view. (Appendix 13) the light emitting device further includes a light reflective member exposing an upper surface of the optical member and covering a side surface of the optical member and a side surface of the light emitting element; 13. The light emitting device of claim 12, wherein the second region has a surface roughness greater than that of the first region. (Appendix 14) The surface roughness of the first region is 0.5 μm or more and 1.0 μm or less in terms of arithmetic mean roughness Ra, 14. The light emitting device according to claim 13, wherein the second region has a surface roughness of 2.0 μm or more and 3.0 μm or less in terms of arithmetic mean roughness Ra. (Appendix 15) 15. The light emitting device according to any one of claims 12 to 14, wherein the first region is inclined with respect to the second region and is located more inward than the second region in a top view. (Appendix 16) A polycrystalline optical member having a first main surface and a second main surface located on the opposite side to the first main surface, the polycrystalline optical member including phosphor particles, An optical member having a convex portion disposed along an outer edge of the first main surface. [Explanation of symbols]

[0102] 1 Light emitting device 10 Wiring board 11 Base material 12 Top wiring 13 Bottom wiring 20 Light emitting element 20a top surface 20b Bottom side 20c side 25 electrodes 30 Protection elements 40 Light guide member 40c side 50 Optical Components 50a First main surface 50b 2nd principal surface 50c,50sc side 50d convex part 50R area 50S Wavelength conversion material 51 First area 52 Second area 60 Light-reflective material 61 First light reflective member 62 Second light reflective member

Claims

1. preparing a polycrystalline wavelength conversion member containing phosphor particles; irradiating a first main surface of the wavelength conversion member with a first laser light to form a groove; irradiating the second laser light so as to overlap the groove, and fracturing the wavelength conversion member starting from the groove; Equipped with A method for manufacturing an optical member, wherein an energy density per unit length in the scanning direction of the second laser light is greater than an energy density per unit length in the scanning direction of the first laser light.

2. The energy density per unit length in the scanning direction of the first laser light is 2.6×10 ３ (J / (cm ２ ・Larger than 8 x 10 mm ４ (J / (cm ２ The method for producing an optical member according to claim 1 , wherein the thickness of the optical member is smaller than the thickness of the optical member.

3. The energy density per unit length in the scanning direction of the second laser light is 4×10 ４ (J / (cm ２ ・Larger than 4 x 10 mm ５ (J / (cm ２ 2. The method for producing an optical member according to claim 1, wherein the thickness of the optical member is less than or equal to 1 mm.

4. The energy density per unit length in the scanning direction of the first laser light is 8×10 ３ (J / (cm ２ ・Larger than 8 x 10 mm ４ (J / (cm ２ mm), and the energy density per unit length in the scanning direction of the second laser light is less than 4×10 ４ (J / (cm ２ ・Larger than 4 x 10 mm ５ (J / (cm ２ 2. The method for producing an optical member according to claim 1, wherein the thickness of the optical member is less than or equal to 1 mm.

5. The method for producing an optical member according to claim 1 , wherein a scanning speed of the second laser light is slower than a scanning speed of the first laser light.

6. The method for producing an optical member according to claim 1 , wherein the peak wavelengths of the first laser light and the second laser light are each within a range of 350 nm to 360 nm.

7. 5. The method for manufacturing an optical member according to claim 1, wherein the depth of the groove from the first main surface is 3 μm or more and is ½ or less of a thickness of the wavelength conversion member.

8. The method for producing an optical member according to claim 1 , wherein in the step of forming the groove, a convex portion is formed outside the groove.

9. The method for producing an optical member according to claim 8 , wherein a height of the convex portion from the first main surface is not less than 1 μm and not more than 5 μm.

10. The method for producing an optical member according to claim 8 , wherein the width of the convex portion is 30 μm or more and 80 μm or less when viewed in a direction perpendicular to the first main surface.

11. A light-emitting element; a light guiding member disposed on the light emitting element; a polycrystalline optical member that is disposed on the light guide member and that contains phosphor particles; the optical member has a convex portion disposed along an outer edge of a lower surface of the optical member, The light guiding member is disposed in a region surrounded by the protrusion when viewed from above.

12. the side surface of the optical member includes a first region located on a lower surface side of the optical member and a second region located on an upper surface side of the optical member, The light emitting device according to claim 11 , wherein the convex portion is located more inward than the second region in a top view.

13. the light emitting device further includes a light reflective member exposing an upper surface of the optical member and covering a side surface of the optical member and a side surface of the light emitting element; The light emitting device according to claim 12 , wherein the second region has a surface roughness greater than that of the first region.

14. The surface roughness of the first region is 0.5 μm or more and 1.0 μm or less in terms of arithmetic mean roughness Ra, The light emitting device according to claim 13 , wherein the second region has a surface roughness of 2.0 μm or more and 3.0 μm or less in terms of arithmetic mean roughness Ra.

15. The light emitting device according to claim 12 , wherein the first region is inclined with respect to the second region and is located more inward than the second region in a top view.

16. A polycrystalline optical member having a first main surface and a second main surface located on the opposite side to the first main surface, the polycrystalline optical member including phosphor particles, An optical member having a convex portion disposed along an outer edge of the first main surface.

Images