JP2017011257A - Light emitting device and light emitting module using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device having light distribution characteristics capable of reducing stray light.SOLUTION: A light emitting device includes a substrate, a light emitting element provided on the substrate, and a light transmissive sealing member covering the light emitting element on the substrate. The light transmissive sealing member includes a body portion and a lens portion which are sequentially disposed from a substrate side. An interior angle formed between the substrate and an outer surface of the body portion is larger than an interior angle formed between the substrate and an outer surface at a lower end portion of the lens portion. An outer surface of the lens portion includes an aspheric surface that has a region located between the lower end portion on a side of the body portion and an apex as an intersection of the outer surface and an optical axis, the region having a curvature radius smaller than that of each of the apex side and the lower end portion side. A length of the lens portion along the optical axis direction is longer than a length of the body portion along the optical axis direction, and, when Wm is a maximum width of a light emitting face of the light emitting element, a diameter Di of the body portion is set to satisfy the following expression: 2.0≥Di/Wm≥1.4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light emitting device.

  In recent years, light emitting devices using light emitting diodes (LEDs) having many features such as low power consumption, long life, and high reliability have been widely used in various applications. Along with such expansion of applications, there is a demand for light emitting devices having light emission characteristics according to each application. For example, in an ink jet recording apparatus, a light emitting element (LED) that emits ultraviolet rays may be used as a light source for curing ink (Patent Document 1). The inkjet recording apparatus includes a holder that ejects ink from an ink head to a medium to be printed while moving in the main scanning direction, and light that moves in the main scanning direction together with the holder and cures the ink ejected from the ink head. And a lamp for irradiating.

  In the ink jet recording apparatus described in Patent Document 1, an ultraviolet light source in which a plurality of LEDs are arranged in a row as the lamp is disclosed.

JP 2009-51095 A

However, in an ink jet recording apparatus, since the ink head and the ultraviolet light source are disposed relatively close to each other, the light from the light source may be reflected by, for example, a medium and irradiated in the ink head direction. There was a problem that would be cured. In order to suppress such light irradiated in the ink head direction, that is, in the lateral direction (hereinafter, sometimes referred to as stray light), the entire inkjet recording apparatus is devised or the light source is devised. Although a recording apparatus has been proposed, there are cases where the overall configuration or the configuration of the light source becomes complicated, or the suppression of stray light is insufficient.
Even in applications other than the inkjet recording apparatus, in order to suppress light emitted in unnecessary directions, a light distribution characteristic corresponding to the application may be required.

  Therefore, an object of the embodiment of the present invention is to provide a light emitting device having a light distribution characteristic capable of suppressing stray light.

  Therefore, a light-emitting device according to an embodiment of the present invention includes a substrate, a light-emitting element provided on the substrate, and a translucent sealing member that covers the light-emitting element on the substrate, The translucent sealing member has a body portion and a lens portion from the substrate side, and an inner angle formed by the substrate and the outer surface of the body portion is an outer surface of the substrate and the lower end portion of the lens portion. The outer surface of the lens unit is between the apex, which is the intersection of the outer surface and the optical axis, and the lower end of the body unit side, the apex side and the lower end side The length of the lens portion in the optical axis direction is longer than the length of the body portion in the optical axis direction, and the maximum width of the light emitting surface of the light emitting element is Wm. The diameter Di of the body portion satisfies 2.0 ≧ Di / Wm ≧ 1.4. It is set to.

  According to the light emitting device configured as described above, a light emitting device having a light distribution characteristic capable of suppressing stray light can be provided.

It is a perspective view which shows the structure of the light-emitting device which concerns on Embodiment 1 of this invention. 3 is a plan view of a light-transmitting sealing member of the light emitting device according to Embodiment 1. FIG. 4 is a cross-sectional view of a light-transmitting sealing member of the light emitting device according to Embodiment 1. FIG. 4 is a graph showing light distribution characteristics of the light emitting device of Example 1 and the light emitting device of Comparative Example 1. 4 is a graph showing the light distribution characteristics emitted from each part of the translucent sealing member 1 in the light emitting device of Example 1. It is sectional drawing of the translucent sealing member in which a shape differs from the trunk | drum part shown in FIG. It is sectional drawing of the translucent sealing member in which a shape differs from the trunk | drum part shown in FIG. It is a perspective view which shows the structure of the light-emitting device which concerns on Embodiment 2 of this invention. It is a side view of the light-emitting device shown to FIG. 7A. It is a top view of the board | substrate of the light-emitting device shown to FIG. 7A. In the light emitting device of Example 2, the maximum width Wm is set to 2.73 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.1. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 2.5 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.2. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 2.31 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.3. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 2.12 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.4. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 1.88 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.6. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 1.76 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.7. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 1.67 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.8. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 1.58 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 1.9. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 2, the maximum width Wm is set to 1.5 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 2.0. did. It is a graph which shows the light distribution characteristic at the time. In the light emitting device of Example 2, the maximum width Wm is set to 1.4 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 2.1. did. It is a graph which shows the light distribution characteristic at the time. In the light emitting device of Example 2, the maximum width Wm is set to 0.85 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is 3.1. It is a graph which shows the light distribution characteristic when doing. In the light emitting device of Example 3, the height t11 of the trunk portion 11 is set to 0. 1 so that the ratio (t12 / t11) of the height t11 of the trunk portion 11 to the height t12 of the lens portion 12 is 1.5. It is a graph which shows the light distribution characteristic when set to 82. In the light emitting device of Example 3, the height t11 of the body 11 is set to 1. so that the ratio (t12 / t11) of the height t11 of the body 11 and the height t12 of the lens 12 is 1.1. 12 is a graph showing light distribution characteristics when set to 12. In the light-emitting device of Example 3, the height t11 of the body 11 is set to 1. so that the ratio (t12 / t11) of the height t11 of the body 11 and the height t12 of the lens 12 is 1.0. 24 is a graph showing light distribution characteristics when set to 23. In the light emitting device of Example 4, the height t11 of the body portion 11 so that the ratio (Di / t1) of the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 is 1.4. It is a graph which shows the light distribution characteristic when the height t12 of the lens part 12 and the height t13 of the connection part 13 are set. In the light emitting device of Example 4, the height t11 of the body portion 11 so that the ratio (Di / t1) of the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 is 1.1. It is a graph which shows the light distribution characteristic when the height t12 of the lens part 12 and the height t13 of the connection part 13 are set.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the light-emitting device described below is for embodying the technical idea of the embodiment, and the present invention is not limited to the following embodied form. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts do not limit the technical scope of the present invention, but are merely illustrative examples and may be exaggerated for clarity of explanation. is there. The embodiments and examples described below can be applied by appropriately combining the components.

<Embodiment 1>
FIG. 1 is a perspective view showing a structure of a light emitting device 10 according to the first embodiment. As shown in FIG. 1, the light emitting device 10 includes a substrate 3, a light emitting element 2 mounted on the substrate 3, and a translucent sealing member 1 that directly covers the light emitting element 2 on the substrate 3. .
And in the light emitting device 10,
(1) The translucent sealing member 1 has a body portion 11 and a lens portion 12 having an aspheric outer surface from the substrate 3 side, and the length of the lens portion 12 in the optical axis direction is the body portion 11. Longer than the length of the optical axis
(2) When the maximum width of the light emitting surface of the light emitting element 2 is Wm, the diameter Di of the body portion 11 is set to satisfy 2.0 ≧ Di / Wm ≧ 1.4.
According to the light emitting device 10 configured as described above, a light emitting device capable of reducing the full width at half maximum of the light intensity distribution with respect to the radiation angle and capable of suppressing stray light when used in, for example, an ink jet recording apparatus is provided. It becomes possible.
Here, the maximum width Wm of the light emitting surface is, for example, the length between diagonals of the light emitting surface in the light emitting device 2 having a square light emitting surface, and in the light emitting device 2 having a circular light emitting surface. In the light-emitting element 2 which has a diameter and a light-emitting surface is an ellipse, it means the length of the major axis of the light-emitting surface.
The diameter Di of the body portion 11 is the diameter of the bottom surface of the body portion 11 on the substrate 3 side.
In addition, the light-emitting device 10 may include the protective element 4 as necessary.
Hereinafter, the configuration of the light emitting device 10 will be described in detail.

The substrate 3 of the first embodiment has a first electrode 31 and a second electrode 32 on the upper surface. The first electrode 31 and the second electrode 32 function as positive and negative wirings. As the light-emitting element 2, for example, a light-emitting diode that mainly emits light having a wavelength in the ultraviolet region (about 200 nm to 410 nm) can be used, but is not limited thereto. The light emitting element 2 has, for example, one positive or negative electrode on the upper surface on the light emitting surface side, and the other electrode provided on the opposite surface is electrically bonded to the first electrode 31 of the substrate 3. The positive or negative electrode on the upper surface may be connected to the second electrode 32 of the substrate 3 by wire bonding. Alternatively, flip-chip mounting may be performed using a light emitting element in which positive and negative electrodes are provided on the same surface, or a surface opposite to the surface on which the electrodes are provided is mounted on the substrate 3, and the positive and negative electrodes are wired. The first electrode 31 and the second electrode 32 may be connected to each other by bonding.
For example, the protective element 4 can be connected in parallel with the light emitting element 2 between the first electrode 31 and the second electrode 32 of the substrate 3.

(Configuration of translucent sealing member 1)
The translucent sealing member 1 can be provided so as to cover the light emitting element 2 on the substrate 3 and the optical axis of the translucent sealing member 1 is located at the center of the light emitting portion of the light emitting element 2. When the protective element 4 is included, the translucent sealing member 1 can be provided on the substrate 3 so as to cover the light emitting element 2 and the protective element 4.

  FIG. 2 is a plan view of the translucent sealing member of the light emitting device according to Embodiment 1. FIG. FIG. 3 is a cross-sectional view of the translucent sealing member of the light emitting device according to Embodiment 1. Although FIG. 3 is a cross-sectional view, hatching is omitted for the sake of clarity. FIG. 4 is a graph showing the light distribution characteristics of the light emitting device of Example 1 and the light emitting device of Comparative Example 1 according to the first embodiment. The translucent sealing member 1 of Embodiment 1 includes a body portion 11 and a lens portion 12 from the substrate 3 side so that the relative intensity of light emitted in the optical axis direction is increased. The surface is aspherical, and the length of the lens portion 12 in the optical axis direction is longer than the length of the body portion 11 in the optical axis direction (see FIG. 3).

(Configuration of the lens unit 12)
In the first embodiment, the curved surface shape of the lens unit 12 mainly determines the light distribution characteristic in the range of the radiation angle from 0 ° to 60 °. The lens unit 12 has an aspheric outer surface having a region in which the radius of curvature R is smaller than the apex side and the lower end side between the apex that is the intersection with the optical axis and the lower end on the body unit 11 side. . Specifically, the outer surface of the aspherical surface has a position 12a where the radius of curvature R is minimized between the apex and the lower end, and the radius of curvature R increases from the position 12a toward the lower end and the apex side. Have.

  Hereinafter, the configuration of the lens unit 12 will be specifically described. In the following description, the positions of the lens portion 12 and the body portion 11 on the outer surface are defined by taking the intersection point between the light emitting surface of the light emitting element 2 and the optical axis of the translucent sealing member 1 as the origin (light emission center). It is indicated by an angle θ formed by a straight line L connecting an arbitrary position on the surface and the origin and the optical axis. The point where the central axis of the light distribution of the light emitting element 2 and the light emitting surface of the light emitting element intersect is called the light emission center. In the present embodiment, preferably, the light emitting element 2 and the translucent sealing member 1 are arranged so that the central axis of the light distribution of the light emitting element 2 and the optical axis of the translucent sealing member 1 coincide. .

In the first embodiment, the lens portion 12, shown in the straight line L ₃ and the angle theta (Fig. 3 with the optical axis connecting the lower end of the body portion 11 side (the boundary between the lens portion 12 and the body portion 11) and the origin It is preferable that θ3) be located in a range of 55 ° to 65 °. The outer surface of the lens unit 12 includes a flat part 121 having a large curvature radius and a substantially flat surface, and a curved surface part having a curvature radius smaller than the flat part 121. The flat portion 121 is a substantially flat surface having a radius of curvature R that is 2.8 times or more the height t12 of the lens portion 12, and as shown in FIG. wherein an intersection) of the surface, the boundary and the origin and a straight line L ₁ and formed by the optical axis angle θ1 following parts connecting the flat portion 121 and the curved surface portion. Further, the curved portion, the angle θ is greater than θ1 formed by the straight line L ₁ and the optical axis, an outer surface located outside of the flat portion 121. Boundary separating the flat portion 121 and the curved portion is a position on the outer surface shown by the straight line L ₁ and the angle .theta.1 formed by the optical axis, the angle .theta.1 defining the boundaries, 15 ° ≦ θ1 ≦ 25 ° It is preferable to set in the range.

If Shimese a more specific example, for example, the lens unit 12 of the embodiment 1 is provided in a range linearly L ₃ and the angle θ3 between the optical axis is expressed by a coordinate than 60 °. In the lens unit 12, for example, a range represented by coordinates where the angle θ <b> 1 from the optical axis is 19 ° or less is a substantially flat portion 121. In the first embodiment, the region corresponding to the light emitting element 2 in the plan view can be the flat portion 121.
Further, the flat portion 121 can be provided in a range where the relative value is represented by 0 to 0.47, where the radius of the lower end portion of the lens portion 12 is 1. Such a flat portion 121 has a relative sag amount z when the height from the upper surface of the light emitting element 2 to the apex of the lens portion 12 is 1 in the range where the relative value is represented by 0 to 0.47. It can be configured by setting the shape of the outer surface so that the value is −0.0314 or less. The flat part 121 may include a completely flat region. The sag amount (sag) z refers to the distance from the straight line perpendicular to the optical axis at the apex of the translucent sealing member 1 to the outer surface of the translucent sealing member 1.

  In the first embodiment, the translucent sealing member 1 has the lens portion 12 in the above-described range, and the flat portion 121 in the lens portion 12 in a certain range centered on the optical axis. In the optical characteristics, the relative light intensity can be increased more effectively on the optical axis with a radiation angle of 0 °. In other words, the light intensity distribution curve can be a cusp having a sharp apex on a radiation angle of 0 ° (optical axis).

In the first embodiment, the outer surface of the lens unit 12 includes a position 12a where the radius of curvature R is minimum in the curved surface part. This position 12a may be a point indicated by one point in the longitudinal section including the optical axis of the translucent sealing member 1, or may be a region indicated by a curve having the same minimum radius of curvature over a certain range. Also good. Angle .theta.2 between the straight line L ₂ and the optical axis of the radius R of curvature connecting the position 12a and the origin becomes minimum is preferably set in a range of 35 ° ≦ θ2 ≦ 45 °, thereby, more effectively Light can be emitted in a concentrated manner in the optical axis direction.
For example, the lens unit 12, the range of the straight line L ₃ and the angle θ3 between the optical axis is expressed by a coordinate than 60 °, the lens unit 12, an angle θ1 from the optical axis is 19 ° or less coordinates range represented is, when the substantially flat planar portion 121, the position 12a to the radius of curvature R is minimized, for example, a position straight line L ₂ and the angle θ2 between the optical axis is represented by 40 ° Set.

In the curved surface portion, the first region 122 is defined from the lower end of the flat portion 121 (boundary between the flat portion 121 and the curved surface portion) to the position 12a where the curvature radius R is minimized, and the lower end of the lens portion 12 (lens portion 12) from the position 12a. And the boundary between the body portion 11 and the body portion 11 is defined as a second region 123.
The first region 122 may, for example, set in the range of the straight line L ₂ and the angle .theta.2 of the optical axis is represented by 19 ° ≦ θ2 ≦ 40 °. In this case, when the radius of the lower end of the lens unit 12 is 1, the relative value of the distance from the optical axis can be provided in a range represented by 0.48 to 0.72. The shape of the outer surface is set so that the relative value of the sag amount z when the height from the top surface to the apex of the lens unit 12 is 1 is greater than −0.0314 and −0.277 or less. Can do.

The second region 123 can be provided in a range represented by coordinates where the angle θ3 from the optical axis is 40 ° <θ3 ≦ 60 ° or less.
The second region 123 can be provided in a range in which the relative value of the distance from the optical axis is represented by 0.73 to 1.0 when the radius h of the lower end portion of the lens unit 12 is 1, and the light emitting element The shape of the outer surface is set so that the relative value of the sag amount z when the height from the upper surface of 2 to the apex of the lens unit 12 is 1 is larger than −0.277 and becomes −0.603. be able to.

  As described above, the outer surface of the lens portion 12 has an aspherical convex curved surface shape having the flat portion 121, the first region 122, and the second region 123 in this order from the top to the lower end in the longitudinal section. ing. The radius of curvature R becomes smaller in the flat portion 121 and the first region 122 as the position represented by the coordinates having a larger angle with the optical axis, and in the second region, the position represented by the coordinates having a larger angle with the optical axis. It gets bigger. The change amount of the curvature radius R is the largest in the first region, and the change amount of the curvature radius R in the flat portion and the second region is smaller than the change amount of the curvature radius R in the first region. With such a configuration, in the light distribution characteristic, the relative light intensity can be increased more effectively on the optical axis with a radiation angle of 0 °.

(Configuration of the body portion 11)
The body part 11 is provided closer to the substrate 3 than the lens part 12 in the translucent sealing member 1. The body portion 11 of the first embodiment is preferably provided so that the upper end portion on the lens portion 12 side is positioned in a range where the angle θ formed by the straight line L and the optical axis is 55 ° or more and 65 ° or less. The body part 11 has an inner angle θ5 of the body part 11 formed by the outer surface of the body 3 and the upper surface of the substrate 3 (hereinafter sometimes referred to as an inner angle θ5 of the body part 11). It is configured to be larger than an inner angle θ4 of the lens portion formed by the upper surface of the substrate 3 (hereinafter, sometimes referred to as an inner angle θ4 of the lower end portion of the lens portion 12). Therefore, in Embodiment 1, it can be set as the outer surface of the trunk | drum 11 which inclines inside the tangent of the lower end part of the lens part 12 shown by FIG. Here, the case where the outer surface of the body portion 11 is perpendicular (90 °) to the substrate 3 is also included. The internal angle θ4 can also be expressed as an angle formed by the tangent to the surface of the lower end portion of the lens portion 12 and the upper surface of the substrate 3 in the cross section including the optical axis.

If the shape of the trunk | drum 11 prescribed | regulated as mentioned above is demonstrated concretely, it can be divided into the following three.
(1) As shown in FIG. 3, the body part 11 (inner angle θ5 of the body part 11 is larger than the inner angle θ4 of the lower end part of the lens part 12 and has an outer surface perpendicular to the substrate 3 (90 °)) That is, a cylindrical shape or an elliptical cylindrical shape),
(2) As shown in FIG. 6A, the body portion 11 (that is, the truncated cone) has an outer surface in which the inner angle θ5 of the body portion 11 is larger than the inner angle θ4 of the lower end portion of the lens portion 12 and smaller than 90 °. Shape or elliptic frustum shape),
(3) As shown in FIG. 6B, the body portion 11 having an outer surface in which the inner angle θ5 of the body portion 11 is larger than the inner angle θ4 of the lower end portion of the lens portion 12 and larger than 90 ° (that is, the optical axis) The reverse tilt is smaller the distance from the substrate side, specifically, the inverted truncated cone shape, the inverted elliptical truncated cone shape)

  In addition, as for the trunk | drum 11 (Cylinder shape, elliptic cylinder shape, (reverse) truncated cone shape, and (reverse) elliptical truncated cone shape) of Embodiment 1, all have an outer surface in the optical axis of the translucent sealing member 1. It is a curve in the orthogonal cross section, and is a straight line in the longitudinal section including the optical axis of the translucent sealing member 1.

  The body part 11 mainly determines the light distribution characteristic in the part where the radiation angle is 60 ° or more and the radiation angle is large, and the interior angle θ5 of the body part 11 is larger than the interior angle θ4 of the lower end part of the lens part 12. The closer the outer surface is (that is, by having a reversely inclined outer surface), the greater the incident angle of light from the light emitting element that is incident on the side surface of the body portion 11. Thereby, more light comes to be reflected by the side surface of the body part 11, and the light relative intensity in the part where the radiation angle is large can be particularly lowered. In addition, it is preferable that the shape of the trunk | drum 11 is a cylindrical shape or an elliptical column shape. Thereby, the translucent sealing member 1 can be easily shape | molded with a metal mold | die, for example.

  In addition, the outer surface of the trunk | drum 11 does not need to be a straight line in a longitudinal section, and an outer surface is a curve in a longitudinal section (for example, a deformed cylindrical shape, a deformed elliptical column shape, a deformed (outer surface is convex outward) The body part 11 may have a conical shape (inverse) and a deformed (inverse) elliptical frustum shape). Further, the outer surface of the body portion 11 may be a straight line in the cross section, and for example, the shape of the body portion 11 may be a polygonal column such as a square column.

  In the first embodiment, the height t12 of the lens unit 12 in the optical axis direction can be 1.1 to 1.5 times the height t11 of the body unit 11 in the optical axis direction, and more preferably. 1.2 times or more and 1.4 times or less. Thereby, the extraction efficiency of the light extracted from the translucent sealing member 1 can be maintained high. In addition, it is preferable that the height t11 of the trunk | drum 11 in the optical axis direction is higher than the height of the light emitting element 2 to coat | cover. By doing so, it is possible to suppress the relative intensity of light in a portion having a large radiation angle.

  As described above, the light emitting device 10 having the translucent sealing member 1 including the body portion 11 described above and the lens portion 12 having an aspheric surface and a flat portion has an emission angle of 0 ° as shown in FIG. Sometimes the change rate of the slope of the light intensity distribution curve takes a maximum value, and a sharp apex is formed on the optical axis in the curve. Moreover, it has the light distribution characteristic by which the light intensity of the part with a large radiation angle was suppressed compared with the light-emitting device of the comparative example 1 which has the translucent sealing member which consists of spherical surfaces.

  Specifically, the full width at half maximum of the light intensity distribution with respect to the radiation angle can be made 70 ° or more and 80 ° or less, and the light intensity with the radiation angle 60 ° or more can be made 20% or less of the light intensity with the radiation angle 0 °. Therefore, the light emitting device 10 according to the first embodiment is suitable for use in, for example, an ink jet recording apparatus in which suppression of stray light irradiated in the lateral direction (that is, light irradiated on a portion having a large radiation angle) is desired. Has optical properties.

  According to the light emitting device 10 of the first embodiment, the aspheric shape of the outer surface of the lens unit 12, the inclination of the outer surface of the body unit 11 with respect to the substrate 3 (inner angle θ 5), and the height of the lens unit 12 in the optical axis direction. By appropriately changing the ratio of t12 and the height t11 of the body portion 11 in the optical axis direction, the light distribution characteristics can be changed as appropriate.

  In addition, a light emitting module can be configured by arranging a plurality of light emitting devices 10 configured as described above at certain intervals. When using the light emitting device 10 having the light distribution characteristics as described above, it is possible to irradiate light uniformly on an irradiation target such as media by arranging a plurality of light emitting devices at regular intervals of about 3.5 mm to 8.0 mm, for example. A light emitting module can be formed.

(Connecting part 13, base part 14, collar part 8)
In the light emitting device 10 according to the first embodiment, as shown in FIG. 3, a connecting portion 13 may be further included between the body portion 11 and the lens portion 12. Further, a base portion 14 may be provided between the lower end portion of the body portion 11 and the substrate 3. The connecting portion 13 has, for example, the same cross-sectional shape as the body portion 11 and the lens portion 12, and can be provided in a truncated cone shape, an elliptic truncated cone shape, or the like. The base 14 can be provided so that the area of the cross section increases toward the substrate 3 side. The connecting portion 13 and the base portion 14 are mainly provided for the convenience of manufacturing such as facilitating the molding of the translucent sealing member 1, and are formed by the body portion 11 and the lens portion 12. The shape is determined so as not to substantially change the light distribution characteristics. However, the connecting part 13 and the base part 14 are more concentrated in the optical axis direction than the light distribution characteristic formed by the body part 11 and the lens part 12, or the body part 11 and the lens part 12. The shape may be determined so as to adjust the light distribution characteristic formed by.
As shown in FIGS. 2 and 3, the light emitting device 10 may have a flange portion 8 that extends outward from the outer edge on the lower end side of the base portion 14 of the lens portion 12. The eaves part 8 can be made into the same rectangular shape as the board | substrate 3 by planar view, for example.

  The translucent sealing member 1 of Embodiment 1 includes the light emitting element 2, the wire 5, the first electrode 31 and the second electrode 32, and other joints in addition to the basic function of setting the light distribution characteristics of the light emitting device. It also has a function of sealing and protecting from dust and external force. In order to fulfill these functions, the material constituting the translucent sealing member 1 has electrical insulation and transmits light emitted from the light emitting element 2 (preferably having a transmittance of 70% or more). It can be formed using a material. Specific examples include silicone resins, modified silicone resins, epoxy resins, modified epoxy resins, phenol resins, polycarbonate resins, acrylic resins, TPX resins, polynorbornene resins, or hybrid resins containing one or more of these resins. Inorganic materials such as glass may be used. Among these, silicone resins and modified silicone resins are preferable because they are excellent in heat resistance and light resistance and have little volume shrinkage after solidification.

  Hereinafter, components other than the translucent sealing member 1 in the light-emitting device 10 of Embodiment 1 are demonstrated.

(Light emitting element 2)
The light emitting element 2 can select a light emission wavelength in a wide range from ultraviolet to infrared by selecting a semiconductor material and appropriately setting a mixed crystal ratio thereof in accordance with an application for which the light emitting device is specified. For example, a light emitting element of a light emitting device used for an ink jet recording apparatus or the like is configured to emit ultraviolet light. Therefore, for example, it is represented by a nitride semiconductor (mainly general formula In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, x + y ≦ 1) that can emit light of a short wavelength. Is preferably used. In addition, an InAlGaAs-based semiconductor, an InAlGaP-based semiconductor, zinc sulfide, zinc selenide, silicon carbide, or the like can also be used. Although the external shape and dimension of the light emitting element 2 can be variously selected, in the first embodiment, for example, an LED chip having a plan view of about 1.0 mm to 2.0 mm square and a thickness of about 50 μm to 400 μm can be used.

(Substrate 3)
As the substrate 3, a wiring substrate having wiring (in the first embodiment, the first electrode 31 and the second electrode 32) that can supply current to the light emitting element 2 and an insulating base material that holds the wiring is used. it can. As the base material, ceramics including aluminum oxide, aluminum nitride, zirconium oxide, zirconium nitride, titanium oxide, titanium nitride or a mixture thereof, thermoplastic resins such as polyphthalamide and liquid crystal polymer, and thermosetting resins such as epoxy resin , Glass epoxy, glass, paper and the like. The base material may be polyimide and a flexible substrate may be used. Further, a white pigment such as titanium oxide may be blended in the base material in order to efficiently reflect light from the light emitting element 2. Examples of the wiring material include metals including copper, iron, nickel, chromium, aluminum, silver, gold, titanium, and alloys thereof. The surface of the wiring may further have a coating of metal or the like. In addition, the board | substrate 3 may be comprised only with wiring. The outer shape of the substrate 3 can be selected as appropriate, such as a flat plate shape and a cavity shape. For example, a flat plate shape having a plan view of about 3.5 mm to 7.0 mm square and a thickness of about 0.5 to 3.0 mm can be used.

ここで、高次の非球面係数のうち、Ａは、０．８２３４２１とし、より高次のＢ，Ｃ，Ｄ，・・・はゼロ（０）とした。また、円錐定数Ｋは、−０．８７８３８９４とし、曲率ｃは、−１．８２２７２７３とした。 <Example 1>
As Example 1, light distribution characteristics were simulated using the light emitting device 10 shown in FIG.
In Example 1, a flat substrate in which a light-emitting element 2 having a 1.4 mm square, a thickness of 0.3 mm, and an emission peak wavelength of about 385 nm in plan view is composed of an electrode (wiring) containing copper and alumina ceramics as a base material. 3 (3.5 mm square in plan view, 0.4 mm thickness), and a translucent sealing member 1 is provided so as to directly cover the light emitting element 2 on the substrate 3. In addition, the translucent sealing member 1 is arrange | positioned so that an optical axis may be located in the center of the light emission part of the light emitting element 2 (In Example 1, the center of the light emitting element 2 by planar view). In this simulation, it is assumed that the entire top surface of the light emitting element 2 is a light emitting surface, and here, a 1.4 mm square light emitting element 2 is used. Therefore, the maximum width Wm of the light emitting surface is given by the distance between the diagonal corners of the upper surface of the light emitting element 2 (the length of the diagonal line) and is 1.98 mm.
In the translucent sealing member 1 of Example 1, the outer surface (aspherical shape) of the lens portion 12 was set by the following equation (1). Specifically, when the optical axis of the lens unit 12 is the origin, the position on the outer surface of the lens unit 12 is determined by the following equation. Here, z is the coordinate (mm) in the height direction, and h is the coordinate (mm) in the direction orthogonal to the height direction.

Here, among the higher-order aspherical coefficients, A is 0.823421, and higher-order B, C, D,... Are zero (0). Further, the conic constant K was set to -0.8788944, and the curvature c was set to -1.8227273.

  Table 1 below shows the z-coordinate (mm) and the h-coordinate (mm) obtained by the above equation (1). Table 1 also shows the relative value of the h coordinate when the radius of the lower end of the lens unit 12 is 1, and the z coordinate when the distance between the light emission center of the light emitting element and the apex of the lens unit is 1. The relative value of h, the change amount Δh of the relative value of the h coordinate, and the change amount Δz (sag amount) of the relative value of the z coordinate are also shown.

  Specifically, a range represented by coordinates in which the angle θ3 with the optical axis of the translucent sealing member is 60 ° or less is the lens portion 12, and is represented by coordinates greater than 60 ° and 90 ° or less. The range to be formed was the body part 11.

The flat portion 121 of the lens unit 12 has a range represented by coordinates where the angle θ1 with the optical axis is 0 ° ≦ θ <20. In Example 1, a range having a diameter of 1.4 mm centered on the optical axis was defined as a flat portion. The sag amount z in the flat portion 121 was set to be −0.068 or less. The radius of curvature R of the flat portion 121 can be set to, for example, approximately 2.44 to 5.27 (approximate value 3.65).
The first region 122 is provided in a range represented by coordinates where the angle θ2 from the optical axis is 20 ° ≦ θ2 ≦ 40 °. In Example 1, a range of 2.2 mm in diameter centered on the optical axis excluding the flat portion 121 was defined as the first region. The sag amount z in the first region 122 was set to be larger than −0.068 and equal to or smaller than −0.596. The curvature radius R of the first region 122 can be set to, for example, 1.44 to 2.44 (approximate value 1.89). In addition, in the range represented by the coordinate whose angle with an optical axis is about 40 degrees, it was set as the structure which has the position 12a where the curvature radius R becomes the minimum (for example, curvature radius R = 1.44).
In addition, a range represented by coordinates where the angle from the optical axis is 40 ° <θ2 ≦ 60 ° was defined as the second region 123. In Example 1, the range of 3.0 mm in diameter centered on the optical axis, excluding the flat portion 121 and the first region 122, was defined as the second region 123. The sag amount z in the second region 123 was set to be greater than -0.596 and equal to or less than -1.30. The radius of curvature R of the second region 123 can be set to, for example, 1.44 to 1.50 (approximate value 1.49). The internal angle θ4 formed by the substrate 3 and the outer surface of the lower end portion of the lens portion 12 (second region 123) was 60 °. In addition, the radius of the lower end part of the lens part 12 is 1.49.

  The translucent sealing member 1 of Example 1 includes a connecting portion 13 between the lens portion 12 and the body portion 11. The connecting portion 13 is connected to the substrate 3 side from the lens portion 12 and has a deformed truncated cone shape whose outer surface has a curvature radius R of about 0.75.

  The trunk portion 11 of the first embodiment is connected to the substrate side 3 from the lens portion 12 and the connecting portion 13 and has a cylindrical shape with a radius of 1.5 mm (an internal angle θ5 formed by the substrate 3 and the outer surface of the trunk portion 11 is 90 °). is there.

  The height of the translucent sealing member 1 of Example 1 in the optical axis direction is 2.42 mm, the height t12 of the lens unit 12 in the optical axis direction is 1.3 mm, and the optical axis direction of the connecting unit 13 The height t11 of the body part 11 in the optical axis direction was set to 1.0 mm.

  As Comparative Example 1, instead of the translucent sealing member 1 of Example 1, a hemispherical surface (radius 1.5 mm, height 1.8 mm (height 1.5 mm from the center of the top surface of the light emitting element to the top of the lens portion) ) And a light distribution characteristic of a light emitting device using a translucent sealing member having a radius of curvature R = 1.5).

  The results are shown in FIG. As shown in FIG. 4, the light intensity of the light emitting device 10 of Example 1 is smaller than the light intensity of the light emitting device of Comparative Example 1 where the angle (radiation angle) formed with the optical axis is other than 0 °. It was confirmed that More specifically, in the light intensity distribution curve of the light emitting device of Example 1, a sharp apex is formed on the optical axis, and the full width at half maximum of the light intensity distribution with respect to the radiation angle is 70 ° or more and 80 ° or less. The light intensity at an angle of 60 ° or more was suppressed to 20% or less of the light intensity at an emission angle of 0 °.

  FIG. 5 is a graph showing light distribution characteristics emitted from each part of the translucent sealing member 1 in the light emitting device of Example 1. As shown in FIG. 5, the line indicated by X <b> 1 is the light distribution characteristic of the light emitted from the flat portion of the lens unit 12, and the line indicated by X <b> 2 is emitted from the portion of the lens unit 12 excluding the flat portion. This is the light distribution characteristic of light, and a line indicated by X3 indicates the light distribution characteristic of light emitted from the outer surface of the body part 11. As shown in FIG. 5, it was confirmed that the light distribution characteristic with the radiation angle of 0 ° to 60 ° is mainly determined by the outer surface made of the aspherical surface of the lens portion 12. In addition, light having a radiation angle of 60 ° or more is emitted from the outer surface of the body portion 11, and the intensity of the emitted light is apparent when compared with the light distribution characteristics shown in Comparative Example 1 in FIG. In addition, it was confirmed that the intensity of the light emitted from the outer surface of the body part 11 was significantly suppressed.

Example 2
In Example 2, the ratio (Di / Wm) is used in order to confirm how the light distribution characteristic changes depending on the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 and the diameter Di of the body portion. The light distribution characteristics at each ratio (Di / Wm) were determined by simulation. Specifically, the simulation was performed by changing only the maximum width Wm of the light emitting surface from the parameters used in the simulation of Example 1.

Simulation 2a
In the simulation 2a, the maximum width Wm was set to 2.73 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.1. The obtained light distribution characteristics are shown in FIG. 8A.

Simulation 2b
In the simulation 2b, the maximum width Wm was set to 2.5 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.2. The obtained light distribution characteristics are shown in FIG. 8B.

Simulation 2c
In the simulation 2c, the maximum width Wm was set to 2.31 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.3. The obtained light distribution characteristics are shown in FIG. 8C.

Simulation 2d
In the simulation 2d, the maximum width Wm was set to 2.12 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.4. The obtained light distribution characteristics are shown in FIG. 8D.

Simulation 2e
In simulation 2e, the maximum width Wm was set to 1.88 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.6. The obtained light distribution characteristics are shown in FIG. 8E.

Simulation 2f
In the simulation 2f, the maximum width Wm was set to 1.76 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.7. The obtained light distribution characteristics are shown in FIG. 8F.

Simulation 2g
In the simulation 2g, the maximum width Wm was set to 1.67 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.8. The obtained light distribution characteristics are shown in FIG. 8G.

Simulation 2h
In the simulation 2h, the maximum width Wm was set to 1.58 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 1.9. The obtained light distribution characteristics are shown in FIG. 8H.

Simulation 2i
In the simulation 2i, the maximum width Wm was set to 1.5 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 2.0. The obtained light distribution characteristics are shown in FIG. 8I.

Simulation 2j
In the simulation 2j, the maximum width Wm was set to 1.4 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 2.1. The obtained light distribution characteristics are shown in FIG. 8J.

Simulation 2k
In the simulation 2k, the maximum width Wm was set to 0.85 so that the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion was 3.1. The obtained light distribution characteristics are shown in FIG. 8K.

As a result of the above simulation, the following was confirmed.
(1) By setting the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 and the diameter Di of the body part to 1.1 or more, the relative light intensity at an emission angle of ± 60 ° is implemented. It can be made lower than the comparative example shown in Example 1.
(2) By setting the ratio (Di / Wm) between the maximum width Wm of the light emitting surface of the light emitting element 2 and the diameter Di of the body part to 1.3 or more and 2.0 or less, light at a radiation angle of ± 60 ° Both the relative intensity and the light relative intensity at the radiation angle ± 30 ° can be made lower than those of the comparative example shown in the first embodiment.
(3) By setting the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body part to be 1.4 or more and 1.8 or less, the light intensity distribution curve is changed to the radiation angle. It can be a cusp having a sharp apex on 0 ° (optical axis).

  By the above simulation, the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion can be set so as to satisfy 2.0 ≧ Di / Wm ≧ 1.3. Preferably, it was confirmed that it is more preferable to set to satisfy 1.8 ≧ Di / Wm ≧ 1.4. Further, when the ratio (Di / Wm) of the maximum width Wm of the light emitting surface of the light emitting element 2 to the diameter Di of the body portion is set so as to satisfy 1.8 ≧ Di / Wm ≧ 1.5, the light intensity distribution curve. The apex of the radiation angle 0 ° (optical axis) can be made sharp, and the relative light intensity at the radiation angle ± 60 ° and the relative light intensity at the radiation angle ± 30 ° can both be lowered.

Example 3
In Example 3, the ratio (t12 / t11) is changed in order to check how the light distribution characteristic changes depending on the ratio (t12 / t11) of the height t11 of the body portion 11 and the height t12 of the lens portion 12. The light distribution characteristics were obtained by simulation for each ratio (t12 / t11). Specifically, the simulation was performed by changing only the height t11 of the body portion 11 from the parameters used in the simulation of Example 1.

Simulation 3a
In the simulation 3a, the height t11 of the body 11 is set to 0.82 so that the ratio (t12 / t11) of the height t11 of the body 11 and the height t12 of the lens 12 is 1.5. . The obtained light distribution characteristics are shown in FIG. 9A.

Simulation 3b
In the simulation 3b, the height t11 of the body 11 is set to 1.12 so that the ratio (t12 / t11) of the height t11 of the body 11 and the height t12 of the lens 12 is 1.1. . The obtained light distribution characteristics are shown in FIG. 9B.

Simulation 3c
In the simulation 3c, the height t11 of the body 11 is set to 1.23 so that the ratio (t12 / t11) of the height t11 of the body 11 and the height t12 of the lens 12 is 1.0. . The obtained light distribution characteristics are shown in FIG. 9C.

As a result of the above simulation, the following was confirmed.
(1) By setting the ratio (t12 / t11) of the height t11 of the body part 11 and the height t12 of the lens part 12 to 1.0 or more, the relative light intensity and the radiation angle ± at the radiation angle ± 60 ° The relative light intensity at 30 ° can be made lower than that of the comparative example shown in Example 1.
(2) By setting the ratio (t12 / t11) between the height t11 of the body portion 11 and the height t12 of the lens portion 12 to 1.0 or more, the light intensity distribution curve is set to a radiation angle of 0 ° (optical axis). It can be pointed with a sharp apex on top.
Further, when the ratio (t12 / t11) of the height t11 of the body portion 11 and the height t12 of the lens portion 12 is set to 1.1 or more and 1.5 or less, the relative light intensity and the radiation at the radiation angle ± 60 °. The relative light intensity at an angle of ± 30 ° can be both lowered.

Example 4
In Example 4, in order to confirm how the light distribution characteristics change depending on the ratio (Di / t1) between the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11, the ratio (Di / The light distribution characteristics were obtained by simulation for each ratio (Di / t1) by changing t1). Specifically, the simulation was performed by changing the height t1 of the translucent sealing member 1 from the parameters used in the simulation of Example 1. The height t1 of the translucent sealing member 1 is the sum of the height t11 of the body part 11, the height t12 of the lens part 12, and the height t13 of the connecting part 13. In the simulation of the fourth embodiment, the height t13 of the connecting portion 13 is 0.12 mm, and the ratio (t12 / t11) between the height t11 of the body portion 11 and the height t12 of the lens portion 12 is 1.3. I did it.

Simulation 4a
In the simulation 4a, the height t11 of the body portion 11 and the lens portion 12 are adjusted so that the ratio (Di / t1) of the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 is 1.4. The height t12 and the height t13 of the connecting portion 13 were set. The obtained light distribution characteristics are shown in FIG. 10A.

Simulation 4b
In the simulation 4b, the height t11 of the body portion 11 and the lens portion 12 are adjusted so that the ratio (Di / t1) of the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 is 1.1. The height t12 and the height t13 of the connecting portion 13 were set. The obtained light distribution characteristics are shown in FIG. 10B.

As a result of the above simulation, the following was confirmed.
(1) By setting the ratio (Di / t1) between the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 to 1.1 or more, the relative light intensity at the radiation angle ± 60 ° and The relative light intensity at the radiation angle ± 30 ° can be made lower than that of the comparative example shown in the first embodiment.
(2) By setting the ratio (Di / t1) between the height t1 of the translucent sealing member 1 and the diameter Di of the body portion 11 to 1.1 or more, the light intensity distribution curve is set to a radiation angle of 0 ° ( It can be a cusp having a sharp apex on the optical axis.
(3) When the ratio (Di / t1) of the height t1 of the translucent sealing member 1 to the diameter Di of the body portion 11 exceeds 1.4, the light relative intensity at a radiation angle of + 30 ° to + 60 ° and There is a tendency that the relative light intensity at a radiation angle of −30 ° to −60 ° increases.

  From the above, the diameter of the translucent sealing member 1 (the diameter Di of the body portion 11) is preferably 1.1 times or more and 1.4 or less than the height of the translucent sealing member 1. .

<Embodiment 2>
FIG. 7A is a perspective view showing the configuration of the light-emitting device 20 according to Embodiment 2 of the present invention. FIG. 7B is a side view of the light-emitting device 20 shown in FIG. 7A. The light emitting device 20 of the second embodiment is mainly different from the light emitting device 10 of the first embodiment in the configuration of the substrate and the translucent sealing member. Specifically, the substrate 3a having the side wall 7 is used, and the side wall 7 is provided with a reflection / light guiding function of the side surface of the body portion 11 of the translucent sealing member 1 shown in the first embodiment. That is, the light relative intensity in a portion with a large radiation angle is obtained by the side wall 7 of the substrate 3a and the translucent sealing member 1a that does not include the body portion 11 (that is, corresponding to the lens portion 12 of the first embodiment). The light emitting device 20 having a light distribution characteristic capable of suppressing stray light is formed at a low level.
About the other structure, the structure of the light-emitting device 10 of Embodiment 1 can be applied suitably, and detailed description may be abbreviate | omitted.

  As shown in FIG. 7A, the light emitting device 20 of Embodiment 2 includes a substrate 3a having a recess 6 surrounded by a side wall 7, and a bottom surface of the recess 6 (that is, on a substrate 3a forming the bottom surface of the recess 6). And a light-transmitting sealing member 1 a that is bonded to the upper surface of the side wall 7 and seals the opening of the recess 6.

FIG. 7C is a plan view of the substrate 3a of the light emitting device 20 shown in FIG. 7A. In the second embodiment, the light emitting element 2a having positive and negative electrodes on the same surface is mounted on the wiring (the anode electrode 31a and / or the cathode electrode 32a) on the bottom surface of the recess 6 with a conductive or nonconductive adhesive. The electrode of the light emitting element 2a and the wiring can be electrically connected by the conductive wire 5 as appropriate. In Embodiment 2, it arrange | positions so that the center of the light emission part of the light emitting element 2a may come to the center of the bottom face of the recessed part 6 by planar view.
The light emitting element 2a may be one having electrodes on the upper and lower sides as in the first embodiment, or may be flip-chip mounted using a light emitting element in which positive and negative electrodes are provided on the same surface. In addition, a light emitting element in which positive and negative electrodes are provided on the same surface is used, a surface opposite to the surface having the electrode is mounted on the wiring, and the electrode and the wiring of the light emitting element 2a are connected by a conductive wire. It doesn't matter. A desired wavelength can be appropriately selected as the emission wavelength of the light emitting element 2a. Further, the size and shape of the light emitting element 2a are not particularly limited. For example, a light emitting element having a rectangular shape in a plan view, a 1.4 mm square, and a thickness of 0.3 mm can be used. In addition, a hexagonal light emitting element may be used. In addition to the light emitting element 2a, a protective element may be disposed on the bottom surface of the recess 6.

  In Embodiment 2, the side wall 7 is provided up to a position higher than the upper surface of the light emitting element 2a. Moreover, it is preferable that the inner surface of the side wall 7 of Embodiment 2 is provided so that the angle formed with the bottom surface of the recess 6 is 90 ° or more. Thereby, the light emitted from the light emitting element 2a can be efficiently reflected and guided toward the lens portion 212, and the light extraction can be improved.

  In Embodiment 2, the thickness of the side wall 7 can be 0.5 mm. By doing so, it is possible to suppress the light from the light emitting element 2a from being transmitted sideways and efficiently guide light upward (in the direction of the lens portion 212). The substrate 3a (side wall 7) can be, for example, a rectangular shape of 3.5 mm × 2.83 mm in plan view, but is not limited thereto. As the material of the substrate 3a, the same material as in the first embodiment can be used, and it is particularly preferable to use ceramics such as aluminum nitride from the viewpoint of light resistance.

In Embodiment 2, the translucent sealing member 1a is joined to the upper surface of the side wall 7 of the substrate 3a to cover the recess 6. The light-transmitting sealing member 1a may be joined to the entire upper surface of the side wall 7 so as to seal the opening of the recess 6 in consideration of the use environment, whereby moisture etc. into the recess 6 can be obtained. Can be prevented and deterioration of the light emitting element 2a can be suppressed. The translucent sealing member 1a is preferably disposed on the side wall 7 so that its optical axis is located at the center of the light emitting portion of the light emitting element 2a.
In the second embodiment, in particular, when using a light emitting element 2a that emits light having a wavelength in the ultraviolet region, as a material of the translucent sealing member 1a, an inorganic material such as glass is used in addition to the resin material as described above. It can be used suitably. By doing so, deterioration of the translucent sealing member 1a can be suppressed. In Embodiment 2, the inside of the recess 6 is a gap, but a member such as a resin or a wavelength conversion member may be provided as appropriate.

The translucent sealing member 1a of Embodiment 2 has a lens part 212 having an outer surface made of an aspherical surface. In the second embodiment, the lens unit 212 is an aspherical lens having a region having a smaller radius of curvature than the apex side and the lower end side between the apex that is the intersection with the optical axis and the lower end on the substrate 3a side. It can be a shape. About a specific shape, since it can be set as the shape similar to the lens part 12 of the translucent sealing member 1 of Embodiment 1, detailed description is abbreviate | omitted.
The light emitted from the light emitting element 2a, the light emitted from the light emitting element 2a, reflected and guided in the direction of the light-transmissive sealing member 1a by the side wall 7 of the substrate 3a, As a result, the light emitting device 20 having a narrow light distribution can be obtained as compared with the case where a translucent sealing member having a hemispherical shape or a flat plate shape is used. That is, in the first embodiment, the light emitting device 10 having the light distribution characteristic in which the stray light is suppressed is formed by the body portion 11 and the lens portion 12 of the translucent sealing member 1, but in the second embodiment, the substrate 3a. By causing the side wall 7 to act as the body portion 11 of the first embodiment, the light emitting device 20 having a light distribution characteristic in which stray light is suppressed can be formed by the side wall 7 and the lens portion 212. For example, the light emitting device 20 can be formed such that the full width at half maximum of the light intensity distribution with respect to the radiation angle is 60 ° or more and 70 ° or less. Note that a light-emitting module in which a plurality of light-emitting devices 20 having the above-described light distribution characteristics are arranged can irradiate uniform light to an irradiation target such as media, and can suppress color unevenness.

  The translucent sealing member 1a of the second embodiment has a flange portion 8 that extends outward from the outer edge on the lower end side of the base portion 14 of the lens portion 212. The flange portion 8 has, for example, a rectangular shape similar to that of the substrate 3a in plan view. In the second embodiment, the translucent sealing member 1a is formed with the adhesive 50 at the four corners so that the outer peripheral portion (end surface) of the flange portion 8 is located on the upper surface of the side wall 7 of the substrate 3a. It is fixed to 3a (side wall 7). In the second embodiment, the entire outer peripheral portion of the flange portion 8 may be bonded to the upper surface of the side wall 7. By doing so, the translucent sealing member 1a can seal the recessed part 6 without gap. It is preferable that the flange portion 8 has a similar shape, which is substantially the same as or larger than the opening shape of the concave portion 6 (the shape of the upper surface inner edge of the side wall 7) in plan view. Thereby, for example, even when the opening shape of the concave portion 6 and the outer edge shape of the lens 212 of the translucent sealing member 1a are different, the concave portion 6 can be easily sealed by the translucent sealing member 1a.

  As the adhesive 50 that joins the translucent sealing member 1a and the substrate 3a (the upper surface of the side wall 7), the above-described resin material, solder such as Au—Sn, or the like can be used. In particular, a silicone resin is preferable from the viewpoint of material cost. For example, by providing a plurality of adhesives 50 at opposing positions (that is, in the vicinity of opposing sides or corners), the translucent sealing member 1a and the substrate 3a can be stably bonded. The adhesive may be provided on the entire upper surface of the side wall 7. In addition, you may join the translucent sealing member 1a and the board | substrate 3a by methods, such as welding and welding, without using an adhesive agent.

  In Embodiment 2, for example, when the height from the bottom surface of the recess 6 to the top surface of the side wall 7 is 0.6 mm, the height (thickness) of the translucent sealing member 1a can be about 1.8 mm. . At this time, the thickness of the lens portion 212 can be about 1.45 mm, and the thickness of the collar portion 8 can be about 0.35 mm. Thereby, for example, it is possible to form the light-emitting device 20 having a narrow light distribution such that the full width at half maximum of the light intensity distribution with respect to the radiation angle is 60 ° or more and 70 ° or less.

In the second embodiment, as shown in FIGS. 7A and 7C, a square anode electrode 31a is provided as a wiring at the center of the bottom surface of the recess 6, and a cathode electrode 32a is provided so as to surround the anode electrode 31a. An anode electrode 31b separated from the anode electrode 31a and the cathode electrode 32a is provided at one corner.
In Embodiment 2, as shown in FIG. 7C, when the light emitting device 20 is mounted, for example, an identification mark for identifying the mounting direction of the light emitting device 20 is formed. Specifically, in the recess 6 having a substantially rectangular shape of the opening, three of the four corners can be defined as an R surface, one as a C surface, and a portion of the C surface as an identification mark C1. .

Further, the identification marks C2 and C3 are formed by forming a pattern on the upper surface of the side wall 7. Specifically, as shown in FIG. 7C, a U-shaped pattern (ie, alphabet C) is formed on the upper surface of the side wall 7 along the outer periphery of the cathode electrode 32a on the bottom surface of the recess 6. C2 and an L-shaped identification mark C3 can be formed along the outer periphery of the anode electrode 31b on which the protective element is placed. Thus, by providing a pattern on the upper surface of the side wall 7 as an identification mark, it is possible to prevent the identification mark from becoming difficult to recognize due to the outer edges of the lens portion 212 and the flange portion 8.
The pattern can be formed by, for example, plating. In particular, by providing the pattern with Au or the like, when the translucent sealing member 1a is bonded onto the side wall 7 using an adhesive such as solder, the bondability can be improved.

  In the second embodiment, the outer surface of the lens portion 212 of the translucent sealing member 1a is arranged between the apex that is the intersection with the optical axis and the lower end on the substrate 3a side from the apex side and the lower end side. However, the present invention is not limited to this. For example, the outer surface of the lens part 212 may be an aspherical surface having a region with a small radius of curvature between the vertex that is the intersection with the optical axis and the lower end part on the substrate 3a side. By doing so, it is possible to form the light emitting device 20 having a narrow light distribution characteristic in which stray light is suppressed.

DESCRIPTION OF SYMBOLS 1,1a Translucent sealing member 2,2a Light emitting element 3,3a Board | substrate 4 Protection element 5 Wire 10,20 Light-emitting device 11 Body part 12,212 Lens part 121 Flat part 122 1st area | region 123 2nd area | region 13 Connection part 14 base 31 first electrode 32 second electrode 6 recess 7 side wall 8 flange C1, C2, C3 identification mark

Claims (17)

A substrate,
A light emitting device provided on the substrate;
A translucent sealing member that covers the light emitting element on the substrate;
The translucent sealing member has a body part and a lens part from the substrate side,
The inner angle formed by the substrate and the outer surface of the body portion is larger than the inner angle formed by the substrate and the outer surface of the lower end portion of the lens portion,
The outer surface of the lens part is a region having a smaller radius of curvature than the apex side and the lower end part side between the apex that is the intersection of the outer surface and the optical axis and the lower end part on the body part side. An aspherical surface having
The length of the lens portion in the optical axis direction is longer than the length of the body portion in the optical axis direction,
The light emitting device is characterized in that when the maximum width of the light emitting surface of the light emitting element is Wm, the diameter Di of the body portion is set to satisfy 2.0 ≧ Di / Wm ≧ 1.4. .   The light emitting device according to claim 1, wherein a diameter Di of the body portion is set so as to satisfy 1.8 ≧ Di / Wm ≧ 1.5.   3. The light emitting device according to claim 1, wherein an upper end portion of the body portion on the lens portion side is in a range represented by coordinates having an angle with the optical axis of 55 ° or more and 65 ° or less.   The outer surface of the lens part has a radius of curvature that increases from a position at which a radius of curvature between the lower end on the body part side and the apex is minimized toward the lower end and the apex side. The light emitting device according to claim 1.   The light emitting device according to any one of claims 1 to 4, wherein the outer surface of the lens unit includes a flat part having a radius of curvature of 2.8 times or more of the height of the lens unit around the optical axis.   In the flat portion, an angle formed by a straight line connecting the intersection of the light emitting surface of the light emitting element and the optical axis of the body portion and an arbitrary position of the lower end of the flat portion and the optical axis is 15 ° or more and 25 °. The light-emitting device according to claim 5, wherein the light-emitting device is provided as follows.   The light emitting device according to claim 1, wherein the body portion is a cylinder or an elliptic cylinder.   The light emitting device according to claim 1, wherein the body portion is an inverted truncated cone or an inverted elliptical truncated cone.   The light emitting device according to claim 1, wherein the light emitting element emits light having a wavelength in an ultraviolet region.   The light emitting device according to any one of 1 to 9, wherein the full width at half maximum of the light intensity distribution with respect to the radiation angle is 70 ° or more and 80 ° or less.   The light emitting device according to any one of 1 to 10, wherein the light intensity with a radiation angle of 60 ° or more is 20% or less of the light intensity with a radiation angle of 0 °.   The light emitting device according to any one of claims 1 to 11, wherein a change rate of a slope in a light intensity distribution curve with respect to a radiation angle has a maximum value at a radiation angle of 0 °.   The length of the lens part in the optical axis direction is 1.1 times or more and 1.5 times or less of the length of the body part in the optical axis direction. apparatus.   The light-emitting device according to claim 1, wherein a diameter of the translucent sealing member is 1.1 times or more and 1.4 or less than a height of the translucent sealing member.   On the outer surface of the lens part, the position where the radius of curvature is minimized is a line connecting the intersection of the light emitting surface of the light emitting element and the optical axis of the body part and the position where the radius of curvature is minimized, and the optical axis. The light-emitting device according to any one of claims 1 to 14, wherein an angle between the angle and the angle is set in a range of 15 ° to 25 °.   The light emitting device according to claim 1, further comprising a connecting portion between the body portion and the lens portion.   A light emitting module comprising a plurality of the light emitting devices according to claim 1 arranged at certain intervals.

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