JP2004088007A - Light emitting diode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance light emitting diode efficiency in radiating in two-dimensional directions, and to improve its mass productivity and reliability. <P>SOLUTION: A light emitting diode 2 has a reflector 4 attached to its light emitting unit 3. Light emitted upward from a light emitting element 8 is reflected almost horizontally by a reflecting surface 3a and then radiated two-dimensionally in all directions. Light emitted sidewise from the light emitting element 8 is radiated in two-dimensional directions from the sides constituting a part of the spherical surface. The small-diameter light emitting unit 3 for two-dimensional radiation is excellent in mass productivity and high in reliability, but it has to have a ring-shape reflector 4 attached to its outside for covering its optical disadvantage. The reflector 4 is formed of an acrylic resin similar to the material of the light emitting unit 3, and is physically and optically coupled to the light emitting unit 3 with an optical adhesive. The upper surface 4a of the reflector 4 connects to the upper surface 3a of the light emitting unit 3 for the formation of a curved surface, and the light emitted by the light emitting element 8 and reflected by the upper surface 4a of the reflector 4 is radiated almost horizontally and in all two-dimensional directions. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention incorporates a small-sized light-emitting diode (hereinafter, referred to as a “light-emitting portion”) that reflects light at least in a two-dimensional direction substantially perpendicular to the light-emitting axis of the light-emitting element by a reflecting surface facing the light-emitting surface of the light-emitting element. And a light emitting diode.
[0002]
In this specification, the LED chip itself is referred to as a “light emitting element”, and the entirety including an optical device such as a package resin or a lens system on which the LED chip is mounted is referred to as a “light emitting diode” or “LED”. I do.
[0003]
[Prior art]
When an LED is used as a monochromatic light source, there is no filter loss unlike an incandescent light bulb, and although there is heat generation, there are no hot spots, and thinning can be achieved. However, the following problems have been encountered in a conventional lighting device using a Fresnel lens.
[0004]
A conventional lamp with a Fresnel lens combination will be described with reference to FIG. FIG. 8 is a cross-sectional view showing the structure of a conventional lamp using a Fresnel lens. The lamp 40 includes a convex lens-shaped LED 41, a Fresnel lens 42, and a front cover lens 43. The light emitted from the LED 41 is condensed to some extent by the radiation surface of the convex lens, reaches the Fresnel lens 42, is radiated by the Fresnel lens 42, is radiated forward as parallel light, and is externally radiated from the front cover lens 43. Is done.
[0005]
However, as shown in the figure, the lamp 40 is thick due to the restriction of the distance between the Fresnel lens 42 and the light source, and light that cannot be lens-controlled in the lateral direction is emitted, so that the light use efficiency is low. Therefore, by using a two-dimensional light emitting LED, a reflecting member installed around the two-dimensional light emitting LED that reflects the two-dimensional light in a substantially vertical direction, and a front cover lens, the light fixture is thin and has high light use efficiency. It can be a lamp.
[0006]
[Problems to be solved by the invention]
However, when the two-dimensional directional LED is reduced in size, the solid angle with respect to the light emitting element is reduced and the radiation efficiency is reduced. In addition, when the LED is made large, such LEDs are formed in a plurality of rows on the lead frame. However, since the interval is about the package diameter, the number of LEDs is small, and the curing time of the LED sealing resin generally takes one hour or more. Inferior. Furthermore, since the internal stress of the LED sealing resin increases, stress damage to the light emitting element and cracks in the package are likely to occur, resulting in poor reliability.
[0007]
Accordingly, it is an object of the present invention to provide a two-dimensional directional light emitting diode having high radiation efficiency, excellent mass productivity, and high reliability.
[0008]
[Means for Solving the Problems]
The light emitting diode according to the first aspect of the present invention is a light emitting unit having a two-dimensional direction reflecting surface that reflects light emitted from a light emitting element embedded with a light transmissive material in at least a two-dimensional plane direction, And a reflector portion having a reflecting surface that is optically coupled at least around the light emitting portion in the two-dimensional direction and is formed by extending the reflecting surface in the two-dimensional direction.
[0009]
As described above, the LED includes the light emitting unit having the two-dimensional reflecting surface and the reflector unit that is at least optically coupled around the light emitting unit, and the reflector unit includes a reflecting surface obtained by extending the two-dimensional reflecting surface. Have. Therefore, this LED is equivalent to a two-dimensional radiating LED having the size of the reflector portion, and can form a large solid angle with respect to the light emitting element, so that the LED has high radiation efficiency.
[0010]
In addition, since such light emitting portions are formed in a plurality on the lead frame but can be miniaturized, the same solid angle is formed by the light emitting element encapsulating resin, but the interval is about the package diameter and the number of the light emitting portions is increased. Can be. In addition, since the LED encapsulating resin curing time is generally one hour or longer, the LED is excellent in mass productivity. Furthermore, while the same solid angle is formed by the light-emitting element sealing resin, the internal stress of the LED sealing resin can be suppressed to a small value, so that stress damage to the light-emitting element and cracking of the package do not occur. Can be expensive.
[0011]
Thus, a two-dimensional directional light emitting diode having high radiation efficiency, excellent mass productivity, and high reliability is obtained.
[0012]
According to a second aspect of the present invention, in the light emitting diode according to the first aspect, the reflector portion is formed to have a small thickness, and light emitted from the light emitting portion reaches a surface facing the reflection surface. Is also reflected in the two-dimensional direction.
[0013]
As a result, in addition to the light reflected on the reflecting surface and reflected in the two-dimensional direction, the light from the light emitting portion is totally reflected and emitted in the two-dimensional direction on the surface facing the reflecting surface, so that more light is emitted. A highly efficient LED is obtained.
[0014]
In this way, a two-dimensional directional light emitting diode having higher radiation efficiency, excellent mass productivity, and high reliability is obtained.
[0015]
According to a third aspect of the present invention, in the light emitting diode according to the first aspect, the reflector portion faces the reflecting surface, and reflects the light reflected in the two-dimensional direction by the two-dimensional reflecting surface and the reflecting surface. It has a step-like reflecting surface that reflects in a direction substantially perpendicular to the dimensional direction.
[0016]
Thus, even without providing a reflection member around the light emitting diode, the reflector portion serves as a reflection member and reflects light in a direction substantially perpendicular to the two-dimensional direction. Therefore, a light emitting diode which is small and can be used as a lamp having high radiation efficiency is obtained.
[0017]
In this manner, a light emitting diode that can be used as a small-sized lamp with high radiation efficiency, has excellent mass productivity, and has high reliability.
[0018]
According to a fourth aspect of the present invention, in the light emitting diode according to any one of the first to third aspects, the two-dimensional reflecting surface of the light emitting portion focuses on the light emitting element or the periphery of the light emitting element, and has an ellipse, a parabola, a hyperbola, or Any one of these approximation curves has a shape rotated around a vertical axis passing through the center of the light emitting surface of the light emitting element.
[0019]
As a result, of the light emitted from the light emitting element, light within a predetermined range reaches the optical surface as a two-dimensional reflecting surface, and all of these lights have an incident angle to the optical surface larger than the critical angle, so that all of the light is totally reflected. Reflected toward the side. Here, the optical surface is focused on the light emitting element or the periphery of the light emitting element, and rotates an ellipse, a parabola, a hyperbola, or a part of any of these approximate curves around a vertical axis passing through the center of the light emitting surface of the light emitting element. Due to this shape, all light reflected on the optical surface travels parallel to the horizontal plane and is emitted in a two-dimensional direction. Since the upper surface of the reflector section has a shape that is continuous with the optical surface, all the light reflected on the upper surface of the reflector section also travels parallel to the horizontal plane and is emitted in the two-dimensional direction.
[0020]
In this manner, a highly reliable light emitting diode having high radiation efficiency in two-dimensional directions, excellent mass productivity, and high reliability can be obtained.
[0021]
A light-emitting diode according to a fifth aspect of the present invention is a light-emitting diode in which a portion facing a light-emitting surface of a buried light-emitting element has a conical shape protruding outward, and is coupled to at least the conical portion and emits light from the light-source portion. And a reflector having a two-dimensional reflecting surface that reflects the light in at least a two-dimensional plane direction.
[0022]
Therefore, the light emitted from the light source unit and reflected by the reflection unit is emitted at least in a two-dimensional plane direction, and the entire light emitting diode functions as a two-dimensional emission light source. As described above, a light emitting diode that can emit light in a two-dimensional direction with high radiation efficiency without using a combination of a light emitting unit having a two-dimensional reflecting surface that reflects light at least in a two-dimensional plane direction and a reflector unit.
[0023]
In this manner, a highly reliable light emitting diode having high radiation efficiency in two-dimensional directions, excellent mass productivity, and high reliability can be obtained.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0025]
Embodiment 1
First, a light emitting diode according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a plan view showing the entire configuration of the light emitting diode according to the first embodiment of the present invention, and FIG. 1B is a longitudinal sectional view. FIG. 2 is an explanatory diagram illustrating characteristics of the light emitting diode according to the first embodiment of the present invention as a two-dimensional directional light source. FIG. 3 is a longitudinal sectional view showing a configuration of a lamp using the light emitting diode according to the first embodiment of the present invention.
[0026]
First, the structure of the LED 2 according to the first embodiment will be described with reference to FIG. As shown in FIG. 1, the LED 2 includes a light emitting unit 3 and a reflector unit 4 attached thereto. The light emitting section 3 mounts the light emitting element 8 on the lead 5a of the pair of upright leads 5a and 5b, and electrically connects the light emitting element 8 and the lead 5b with a wire (not shown). The tips of the leads 5a, 5b, the light emitting element 8, and the wire are set in a resin sealing mold, and are sealed with a transparent epoxy resin in a sectional shape as shown in the figure.
[0027]
Here, a minute flat surface is formed at the center of the upper surface 3a of the light emitting section 3. Following this center point, a part of a parabola having the center of the light emitting surface of the light emitting element 8 as a substantially focal point and a symmetric axis in the X axis direction is rotated about the Z axis as a reflecting surface 3a as a two-dimensional emitting surface. It is shaped like an umbrella. The side surface of the light emitting unit 3 forms a part of a spherical surface centered on the light emitting element 8. The light emitted upward from the light emitting element 8 is reflected in a substantially horizontal direction by the reflection surface 3a, and is emitted in a 360-degree two-dimensional direction. Further, the light radiated laterally from the light emitting element 8 is radiated in a two-dimensional direction from the side surface forming a part of the spherical surface.
[0028]
Such a light emitting portion 3 for two-dimensional radiation with a small diameter is excellent in mass productivity and has high reliability but is optically disadvantageous. Therefore, a ring-shaped reflector unit 4 is attached to the outside of the light emitting unit 3. The reflector section 4 is formed of an acrylic resin having the same refractive index as that of the light emitting section 3 and is physically and optically bonded by an optical bonding agent. Note that physical bonding is not necessarily required. In addition, since the gap between the light emitting unit 3 and the reflector unit 4 is small and their respective interfaces are substantially parallel, light loss is small without using an optical bonding agent, and it is not always necessary to use an optical bonding agent. .
[0029]
In addition, since the light emitting section 3 seals the light emitting element 8 and forms the reflecting surface 3a, the reflecting surface 3a can be close to the light emitting element 8, and the height is about 0.3 mm, which is about the wire height. Is also possible. By approaching, a large solid angle can be obtained geometrically, which is optically advantageous over forming the reflection surface 3a with another member.
[0030]
The upper surface 4a of the reflector unit 4 has a curved surface that is continuous with the upper surface 3a of the light emitting unit 3, and the light emitted from the light emitting element 8 and reflected by the upper surface 4a of the reflector unit 4 is substantially horizontally oriented in a 360-degree two-dimensional direction. Is radiated. Here, the outer diameter of the light emitting unit 3 is φ5, and the outer diameter of the reflector unit 4 is φ20. The optical advantage of attaching the reflector unit 4 will be described with reference to FIG. As shown in FIG. 2, in the case of only the light emitting unit 3, only light within an angle of θ1 is emitted in a two-dimensional direction from a perpendicular passing through the center of the light emitting element 8. Since light is radiated in the two-dimensional direction up to light within the angle of θ2, light radiated within the angle of θ1 to θ2 can also be effectively radiated in the two-dimensional direction.
[0031]
Although FIG. 2 shows a two-dimensional display by a cross section, a remarkable effect can be obtained because the light is actually within a solid angle in the range of θ1 to θ2.
[0032]
Such a lamp using the light emitting diode 2 of the first embodiment will be described with reference to FIG. As shown in FIG. 3, the lamp 1 using the LED 2 according to the first embodiment has an LED 2 as a two-dimensional directional radiation light source having a light emitting element built-in at the center, and a reflection member installed around the LED 2. An approximately 45-degree oblique portion 6a of the stepped surface 6 is a reflection surface. Further, a front cover lens 7 that covers these components is provided. When power is supplied to the lead 5 of the LED 2, light from the light emitting element is radiated in a two-dimensional direction of 360 degrees from the side surface of the reflector unit 4 attached around the light emitting unit 3 of the LED 2, and these lights are reflected by the reflecting member. The light is reflected in a substantially vertical direction by the reflecting surface 6a of the light source 6, and is emitted from the front cover lens 7 to the outside.
[0033]
Here, the two-dimensional direction means the direction of the LED 2 toward the reflection surface 6a of the reflection member 6 installed around the LED 2. Strictly, it is sufficient that the light from the LED 2 is not efficiently radiated from the LED 2 in a plane direction perpendicular to the Z axis, but is efficiently radiated to the reflection surface provided around the LED 2.
[0034]
As described above, the lamp 1 using the light emitting diode 2 according to the first embodiment is extremely thin, most of the light emitted from the LED 2 is effectively used, and the external light is extremely efficiently emitted from the front cover lens 7. .
[0035]
Embodiment 2
Next, a light emitting diode according to a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a longitudinal sectional view showing the entire configuration of the light emitting diode according to the second embodiment of the present invention.
[0036]
As shown in FIG. 4, the LED 12 according to the second embodiment has the same structure of the light emitting unit 3 as the first embodiment. However, the bottom surface 14b of the reflector portion 14 is raised close to the mounting surface of the light emitting element 8, and the reflector portion 14 is thin. As a result, not only the light radiated upward from the light emitting element 8 but also the light radiated downward from the side surface of the light emitting element 8 to the bottom surface 14b of the reflector portion 14 becomes larger and exceeds the critical angle. The light is totally reflected by the bottom surface 14b of the portion 14 and is emitted in a two-dimensional direction from the side surface of the reflector portion 14.
[0037]
Further, since the light emitting element 8 has a size, some light is reflected by the upper surface 14a of the reflector portion 14 and is not radiated in the horizontal direction as shown in the figure but is reflected downward, but such light is also reflected by the reflector. The light is totally reflected by the bottom surface 14b of the portion 14 and is emitted in a two-dimensional direction from the side surface of the reflector portion 14.
[0038]
As a result, the amount of light radiated in the two-dimensional direction from the LED 12 increases, and the two-dimensional radiating LED with higher radiation efficiency is obtained.
[0039]
Embodiment 3
Next, a light emitting diode according to a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a longitudinal sectional view showing the entire configuration of the light emitting diode according to the third embodiment of the present invention.
[0040]
As shown in FIG. 5, the LED 21 according to the third embodiment has the same structure of the light emitting unit 3 as the first embodiment. However, the bottom surface of the reflector portion 24 is formed in a step-like shape, and the slope portion is a reflection surface 24b, and light reflected two-dimensionally from the upper surfaces 3a, 24a is reflected upward by the reflection surface 24b. The light reflected upward is radiated externally from the upper surface 24a of the reflector portion 24. At this time, refraction occurs on the upper surface 24a, so that the direction of reflection by the reflecting surface 24b is changed so that the refracted light is radiated to the outside almost vertically. Control. If the angle of the reflecting surface 24b with respect to the two-dimensional radiated light does not become the total reflection, it is necessary to secure a high reflectivity by subjecting the reflecting surface 24b to mirror treatment such as metal deposition from the outside.
[0041]
By forming the reflecting surface 24b for reflecting the two-dimensional radiated light in a substantially vertical direction on the bottom surface of the reflector portion 24 in this manner, the light emitting diode 21 serves as a small lamp.
[0042]
Embodiment 4
Next, a fourth embodiment of the light emitting diode of the present invention will be described with reference to FIG. FIG. 6A is a plan view showing the entire configuration of the light emitting diode according to the fourth embodiment of the present invention, and FIG. 6B is a longitudinal sectional view.
[0043]
As shown in FIG. 6, the LED 31 of the fourth embodiment has the same structure of the light emitting unit 3 as that of the first embodiment. However, the outer shape of the reflector portion 34 is circular in each of the above embodiments, but is elliptical in the fourth embodiment. Further, the bottom surface of the reflector portion 34 is formed in a step-like manner as in the third embodiment, the slope portion is a reflection surface 34b, and the light reflected two-dimensionally from the upper surfaces 3a, 34a is reflected by the reflection surface. The light is reflected upward at 34b. The light reflected upward is radiated externally from the upper surface 34a of the reflector portion 34. At this time, since the light is refracted on the upper surface 34a, the direction of reflection by the reflecting surface 34b is changed so that the refracted light is radiated to the outside almost vertically. Control. Then, if the angle of the reflecting surface 34b with respect to the two-dimensional radiated light does not become the total reflection, it is necessary to secure a high reflectivity by externally performing mirror processing such as metal deposition on the reflecting surface 34b.
[0044]
Further, as shown in FIG. 6A, the bottom surface of the reflector portion 34 is divided into eight segments, and the reflecting surfaces 34b of the adjacent segments are formed so as to be alternate. Then, by giving each reflecting surface 34b a curvature in accordance with the irradiation density from the light emitting section 3, the brightness of the entire light emitting diode 31 can be made uniform. As a result, when viewed from above, the light emitting diode 31 can be a natural image in which the overall brightness of the light emitting diode 31 is uniform and sparkling. Further, even when the light emitting diode 31 is turned off, external light is reflected and the whole becomes uniform and glittering, so that the light emitting diode has a very good appearance.
[0045]
Embodiment 5
Next, a fifth embodiment of the light emitting diode of the present invention will be described with reference to FIG. FIG. 7 is a longitudinal sectional view showing the entire configuration of the light emitting diode according to the fifth embodiment of the present invention.
[0046]
As shown in FIG. 7, unlike the above embodiments, the LED 51 of the fifth embodiment includes a light source unit 53 and a reflection unit 54. That is, in the light source unit 53, the light emitting element 8 is mounted on the lead 55a of the pair of standing leads 55a and 55b, and the light emitting element 8 and the lead 55b are electrically connected by a wire (not shown). The tips of the leads 55a and 55b, the light emitting element 8, and the wire are set in a resin sealing mold, and the transparent epoxy resin is used to seal the resin into a conical shape and a cylindrical shape as shown in the figure. Is done.
[0047]
A reflecting portion 54 made of an acrylic resin having a refractive index equivalent to that of the transparent epoxy resin and having a concave portion corresponding to the conical portion of the light source portion 53 at the center portion is physically and optically formed by an optical bonding agent at the conical portion. Are joined. Note that physical bonding is not necessarily required. Further, since the gap between the light source 53 and the reflector 54 is small and the respective interfaces are substantially parallel, the light loss is small without using an optical bonding agent, and the optical bonding agent does not always have to be used. .
[0048]
The upper surface 54a of the reflector 54 is a two-dimensional reflecting surface on which light emitted from the light emitting element 8 is reflected in a substantially two-dimensional parallel direction. Therefore, when power is supplied to the pair of leads 55a and 55b to cause the light emitting element 8 to emit light, the light reflected by the upper surface 54a upward is reflected substantially horizontally in a 360-degree two-dimensional direction, and is reflected by the reflecting portion 54. Radiation from the sides of the
[0049]
As described above, a light emitting diode that can emit light in a two-dimensional direction with high radiation efficiency without using a combination of a light emitting unit having a two-dimensional direction reflecting surface that reflects light in a two-dimensional plane direction and a reflector unit. The reflecting portion 54 is not necessarily limited to the one that couples only to the conical portion of the light source portion 53, and may be one that couples to the cylindrical portion of the light source portion 53 thereunder.
[0050]
In each of the above embodiments, it is assumed that a red light emitting element is used as the light emitting element, but any color light emitting element may be used. Although a transparent epoxy resin is used as a light transmitting material for sealing a light emitting element and the like in the light emitting portion and the light source portion, other materials such as a transparent silicon resin may be used.
[0051]
In addition, the flat surface at the center of the upper surface of the light emitting unit may be concave or convex, or may have a reflective surface formed from the center. The reflecting surface is not limited to a shape in which a part of a parabola having the X axis as a symmetric axis is rotated around the Z axis, but may be an ellipse, a parabola, a hyperbola, or an approximate curve thereof focusing on the light emitting element or the periphery of the light emitting element. Can be radiated to a predetermined range even when a part of is rotated around the Z axis.
[0052]
Further, in each of the above embodiments, the outer shape of the reflector portion and the reflecting portion is circular or elliptical, but may be other shapes. Further, acrylic resin is used as a material of the reflector portion and the reflection portion, but any material having a refractive index equivalent to that of the sealing material of the light emitting portion may be used.
[0053]
The configuration, shape, quantity, material, size, connection relationship, and the like of other portions of the light emitting diode are not limited to the above embodiments.
[0054]
【The invention's effect】
As described above, the light-emitting diode according to the first aspect of the present invention has a two-dimensional reflecting surface that reflects light emitted from a light-emitting element embedded with a light-transmitting material in at least a two-dimensional plane direction. And a reflector unit having a reflecting surface that is optically coupled around at least the two-dimensional direction of the light emitting unit and extends the reflecting surface in the two-dimensional direction.
[0055]
As described above, the LED includes the light emitting unit having the two-dimensional reflecting surface and the reflector unit that is at least optically coupled around the light emitting unit, and the reflector unit includes a reflecting surface obtained by extending the two-dimensional reflecting surface. Have. Therefore, this LED is equivalent to a two-dimensional radiating LED having the size of the reflector portion, and can form a large solid angle with respect to the light emitting element, so that the LED has high radiation efficiency.
[0056]
In addition, since such light emitting portions are formed in a plurality on the lead frame but can be miniaturized, the same solid angle is formed by the light emitting element encapsulating resin, but the interval is about the package diameter and the number of the light emitting portions is increased. Can be. In addition, since the LED encapsulating resin curing time is generally one hour or longer, the LED is excellent in mass productivity. Furthermore, while the same solid angle is formed by the light-emitting element sealing resin, the internal stress of the LED sealing resin can be suppressed to a small value, so that stress damage to the light-emitting element and cracking of the package do not occur. Can be expensive.
[0057]
Thus, a two-dimensional directional light emitting diode having high radiation efficiency, excellent mass productivity, and high reliability is obtained.
[0058]
According to a second aspect of the present invention, in the light emitting diode according to the first aspect, the reflector portion is formed to have a small thickness, and light emitted from the light emitting portion reaches a surface facing the reflection surface. Is also reflected in the two-dimensional direction.
[0059]
As a result, in addition to the light reflected on the reflecting surface and reflected in the two-dimensional direction, the light from the light emitting portion is totally reflected and emitted in the two-dimensional direction on the surface facing the reflecting surface, so that more light is emitted. A highly efficient LED is obtained.
[0060]
In this way, a two-dimensional directional light emitting diode having higher radiation efficiency, excellent mass productivity, and high reliability is obtained.
[0061]
According to a third aspect of the present invention, in the light emitting diode according to the first aspect, the reflector portion faces the reflecting surface, and reflects the light reflected in the two-dimensional direction by the two-dimensional reflecting surface and the reflecting surface. It has a step-like reflecting surface that reflects in a direction substantially perpendicular to the dimensional direction.
[0062]
Thus, even without providing a reflection member around the light emitting diode, the reflector portion serves as a reflection member and reflects light in a direction substantially perpendicular to the two-dimensional direction. Therefore, a light emitting diode which is small and can be used as a lamp having high radiation efficiency is obtained.
[0063]
In this manner, a light emitting diode that can be used as a small-sized lamp with high radiation efficiency, has excellent mass productivity, and has high reliability.
[0064]
According to a fourth aspect of the present invention, in the light emitting diode according to any one of the first to third aspects, the two-dimensional reflecting surface of the light emitting portion focuses on the light emitting element or the periphery of the light emitting element, and has an ellipse, a parabola, a hyperbola, or Any one of these approximation curves has a shape rotated around a vertical axis passing through the center of the light emitting surface of the light emitting element.
[0065]
As a result, of the light emitted from the light emitting element, light within a predetermined range reaches the optical surface as a two-dimensional reflecting surface, and all of these lights have an incident angle to the optical surface larger than the critical angle, so that all of the light is totally reflected. Reflected toward the side. Here, the optical surface is focused on the light emitting element or the periphery of the light emitting element, and rotates an ellipse, a parabola, a hyperbola, or a part of any of these approximate curves around a vertical axis passing through the center of the light emitting surface of the light emitting element. Due to this shape, all light reflected on the optical surface travels parallel to the horizontal plane and is emitted in a two-dimensional direction. Since the upper surface of the reflector section has a shape that is continuous with the optical surface, all the light reflected on the upper surface of the reflector section also travels parallel to the horizontal plane and is emitted in the two-dimensional direction.
[0066]
In this manner, a highly reliable light emitting diode having high radiation efficiency in two-dimensional directions, excellent mass productivity, and high reliability can be obtained.
[0067]
A light emitting diode according to a fifth aspect of the present invention is configured such that a portion facing a light emitting surface of a buried light emitting element has a conical shape protruding outward, and is coupled to at least the conical portion and emits light from the light source portion. And a reflector having a two-dimensional reflecting surface that reflects the light in at least a two-dimensional plane direction.
[0068]
Therefore, the light emitted from the light source unit and reflected by the reflection unit is emitted at least in a two-dimensional plane direction, and the entire light emitting diode functions as a two-dimensional emission light source. Thus, a light emitting diode that can emit light in two-dimensional directions with high radiation efficiency without using a combination of a light-emitting unit having a two-dimensional reflecting surface that reflects light in at least a two-dimensional plane direction and a reflector unit.
[0069]
In this manner, a highly reliable light emitting diode having high radiation efficiency in two-dimensional directions, excellent mass productivity, and high reliability can be obtained.
[Brief description of the drawings]
FIG. 1A is a plan view showing the entire configuration of a light emitting diode according to a first embodiment of the present invention, and FIG. 1B is a longitudinal sectional view.
FIG. 2 is an explanatory diagram showing characteristics of the light-emitting diode according to the first embodiment of the present invention as a two-dimensional directional light source;
FIG. 3 is a longitudinal sectional view showing a configuration of a lamp using the light emitting diode according to the first embodiment of the present invention.
FIG. 4 is a longitudinal sectional view illustrating an entire configuration of a light emitting diode according to a second embodiment of the present invention.
FIG. 5 is a longitudinal sectional view showing the entire configuration of the light emitting diode according to the third embodiment of the present invention.
FIG. 6A is a plan view showing an entire configuration of a light emitting diode according to a fourth embodiment of the present invention, and FIG. 6B is a longitudinal sectional view.
FIG. 7 is a longitudinal sectional view showing the entire configuration of a light emitting diode according to a fifth embodiment of the present invention.
FIG. 8 is a cross-sectional view showing the structure of a conventional lamp using a Fresnel lens.
[Explanation of symbols]
2,12,21,31,51 Light emitting diode 3 Light emitting portion 3a Two-dimensional emitting surface 4,14,24,34 Reflector portion 4a, 14a, 24a, 34a Reflecting surface 8 Light emitting element 14b Surface 24b facing the reflecting surface, 34b Step-shaped reflective surface 53 Light source 54 Reflector

Claims (5)

Light emitted from the light-emitting element embedded by the light-transmitting material, a light-emitting unit having a two-dimensional direction reflecting surface that reflects light in at least a two-dimensional plane direction,
A light emitting diode, comprising: a reflector portion having a reflecting surface that is optically coupled around at least a two-dimensional direction of the light emitting portion and extends the two-dimensional reflecting surface. The reflector according to claim 1, wherein the reflector is formed to have a small thickness, and also reflects, of the light emitted from the light emitting unit, light that reaches a surface facing the reflection surface in the two-dimensional direction. A light emitting diode as described. The reflector unit has a step-like reflecting surface facing the reflecting surface and reflecting the light reflected in the two-dimensional direction by the two-dimensional reflecting surface and the reflecting surface in a direction substantially perpendicular to the two-dimensional direction. The light emitting diode according to claim 1, wherein: The two-dimensional reflecting surface of the light-emitting unit has a light-emitting element or a periphery of the light-emitting element as a focal point, and an ellipse, a parabola, a hyperbola, or a part of any of these approximated curves passes through the center of the light-emitting element. The light emitting diode according to claim 1, wherein the light emitting diode has a shape rotated around an axis. A light source section in which a portion facing the light emitting surface of the embedded light emitting element has a conical shape protruding outward,
A light-emitting diode, comprising: a reflecting portion coupled to at least the conical portion and having a two-dimensional reflecting surface for reflecting light emitted from the light source portion in at least a two-dimensional plane direction.

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