JP2009027193A - Light-emitting diode, and led light - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting diode which achieves a reduction in thickness and superior productivity, and suppress the irregularity of light distribution characteristics to exhibit uniform brightness in all directions, and to provide an LED light. <P>SOLUTION: The light distribution characteristics I of the light-emitting element 6 of an LED 2 constituting a proximity optical system is given by (θ)=k×cosθ+(1-k)×sinθ, where k is determined to be equal to or less than 0.8. The light-emitting element 6 and an optical surface are formed integrally by a transfer mold method. Light in the X axis direction emitted from the LED 2 to reach a reflective mirror 3 hardly causes total light quantity deviation in an effective projection range, and is reflected by the reflective mirror 3 to project almost uniformly in the Z axis direction. This provides a flat lighting device which has a large reflective mirror surface with no brightness difference thereon and offers fine appearance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light-emitting diode (hereinafter referred to as “LED”) and an LED light using the same, and in particular, a lamp such as a taillight or a brake light of an automobile, or a warning lamp or sign for construction. The present invention relates to a light emitting diode and an LED light used as a display device.

  In recent years, as the brightness of LEDs has increased, LED lights using LEDs as light sources have been increasingly used for lamps such as automobile backlights. The LED has a sharp spectrum, excellent visibility, and has a merit that the signal transmission speed to the succeeding vehicle is improved because the response speed when lighting is fast. It is expected to increase safety. Furthermore, since the LED itself is a monochromatic light source, it is not necessary to filter light other than the necessary color like an incandescent light bulb, and it is highly efficient as a monochromatic light source, leading to energy saving.

  FIG. 13 shows a conventional LED light 200. The LED light 200 includes, as a lens-type LED 201, a light emitting element 202, a pair of lead frames 203a and 203b, a bonding wire 204 that electrically connects the light emitting element 202 and the lead frame 203b, and a transparent epoxy resin 205. Have. The light emitting element 202 is mounted on a lead frame 203a. The light emitting element 202 and the lead frame 203b are wire-bonded, and the whole is sealed in a convex lens shape with a transparent epoxy resin 205.

  Further, as components of the LED light 200, a rotating paraboloidal reflecting mirror 206 that reflects light emitted from the lens-type LED 201 upward, a Fresnel lens 207 positioned above the lens-type LED 201, and light incidence A resin lens 209 having an uneven interface 209a on the side is provided.

  The LED light 200 described above emits light upward and obliquely upward by causing the lens-type LED 201 to emit light. The light emitted above the lens-type LED 201 is collected by the Fresnel lens 207 and emitted as parallel light. Further, the light emitted obliquely above the lens-type LED 201 is reflected by the reflecting mirror 206 and emitted upward. In this way, all the light emitted from the lens-type LED 201 is emitted substantially parallel to the resin lens 209 side. The resin lens 209 diffuses incident light at the uneven interface 209 a and radiates it from the resin lens 209. As a result, the resin lens 209 emits light having a spread of about 20 degrees, which is the standard for in-vehicle backlights.

  However, in the conventional LED light 200, the light emitted from the lens-type LED 201 is converted into parallel light by the Fresnel lens 207 disposed on the light emission side, and this parallel light is diffused by the resin lens 209. There is an inconvenience that the thickness of the system is increased and the LED lamp is enlarged. If the reflecting mirror 206 is omitted, the number of parts can be reduced and the thickness can be reduced, but the light emitted from the light emitting element 202 obliquely upward and in the side surface direction cannot be used, and the radiation efficiency is lowered. Further, since the emitted light passes through the Fresnel lens 207 and the resin lens 209 and is emitted to the outside, the degree of freedom in appearance is low.

  Therefore, for example, Patent Document 1 discloses an LED light that is thin and has a good appearance and that can increase the radiation efficiency.

JP 2001-93312 (FIG. 2)

  This LED light is a light source such as an LED, and a first reflection that reflects light emitted from the light source disposed at a position on the central axis facing the light source as light in a direction substantially orthogonal to the central axis of the light source. A mirror, and a second reflecting mirror disposed around the first reflecting mirror and reflecting the light reflected by the first reflecting mirror as light in the direction of the central axis. Yes. In such a configuration, the light emitted from the light source is reflected by the first reflecting mirror in a direction substantially orthogonal to the central axis, and the reflected light is reflected by the second reflecting mirror in the central axis direction. Vehicle signal light having a predetermined radiation angle can be emitted over a predetermined area.

  However, according to the LED light of Patent Document 1, since most of the emitted light from the light source is emitted upward, if the positional accuracy of the central axis of the light source with respect to the first reflecting mirror is reduced, the first reflecting mirror As a result, the amount of reflected light reflected in the total reflection direction becomes non-uniform, and there is a problem that light and dark (brightness difference) occurs on the surface of the LED light. In particular, as the light source and the first reflecting mirror come closer to each other, the difference in brightness due to the positional deviation becomes significant. Further, the light source and the first reflecting mirror are separate parts, and each of them must be positioned and must be held so as not to be displaced, which takes time for manufacturing. Furthermore, when a physical force is applied, the position of the component may be displaced.

  Even if the light source and the first reflecting mirror are positioned with high accuracy, it is difficult to avoid variations in light distribution characteristics due to the structure of the light source. LEDs with high light concentration have a large effect on the light distribution characteristics due to misalignment of the light emitting elements. When a light source with such a variation in light distribution characteristics is used, there is an inherent problem that light and darkness occurs on the surface of the LED light. It is to do.

  Accordingly, an object of the present invention is to provide a light-emitting diode and an LED light that achieves a reduction in thickness, is excellent in productivity, and has a uniform brightness in all directions while suppressing variations in light distribution characteristics.

In order to achieve the above object, the present invention includes a light emitting element mounted on a power supply means, and a sealing means made of a translucent material that seals the light emitting element, and the sealing means includes the light emitting element. A reflection surface that reflects light emitted from the element in a direction orthogonal to or at a large angle with the central axis of the light emitting element, and a side emission surface that emits light reflected by the reflection surface from the side surface. The shortest distance between the reflecting surface and the light emitting element is less than 1/2 with respect to the radius R of the reflecting surface, and forms a proximity optical system with respect to the light emitting element. When the radiation intensity at the emission angle θ of the emitted light with respect to is I (θ), and the constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k,
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
A light emitting diode is provided.

In order to achieve the above object, the present invention includes a light emitting element mounted on a power supply unit, and a sealing unit made of a translucent material that seals the light emitting element. A reflecting surface that reflects light emitted from the light emitting element in a direction orthogonal to or at a large angle with the central axis of the light emitting element; and a side emitting surface that emits the light reflected by the reflecting surface from the side surface. The reflective surface is formed to have a dimension in which a radius R is larger than a height H in a central axis direction of the light emitting element from the light emitting surface of the light emitting element to an edge of the reflective surface. A close-up optical system,
The light emitting element has a radiation intensity at an emission angle θ of the emitted light with respect to the central axis direction as I (θ), and a constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k,
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
A light emitting diode is provided.

  In the light-emitting diode, the light-emitting element preferably has k ≦ 0.6 with respect to the constant k.

  In the above light emitting diode, the light emitting element may have a light transmitting substrate that is light transmissive with respect to the emitted light.

  In the above light emitting diode, the sealing means may include a light diffusing material that covers the light emitting element.

  In the light emitting diode, the light diffusing material may be a phosphor.

  Moreover, in the light emitting diode, it is preferable that the sealing means is formed so that the thickness h on the light emitting surface side of the light emitting element in the central axis portion of the light emitting element is 1 mm or less.

  In the light emitting diode, the light emitting element may be mounted on an end of the power supply means.

  In order to achieve the above object, the present invention provides an LED light comprising the light emitting diode and a reflecting mirror that reflects light emitted from the light emitting diode.

As described above, the light-emitting diode of the present invention includes a light-emitting element mounted on a power supply unit, and a sealing unit made of a light-transmitting material that seals the light-emitting element. A reflecting surface that reflects light emitted from the light emitting element in a direction orthogonal to or at a large angle with the central axis of the light emitting element; and a side emitting surface that emits light reflected by the reflecting surface from a side surface. The reflective surface has a shortest distance from the light emitting element of less than ½ of the radius R of the reflective surface, and forms a proximity optical system with respect to the light emitting element.
According to such a configuration, light emitted from the light emitting element can be emitted not only in the central axis direction but also in a direction perpendicular to the central axis while reducing the thickness of the light emitting diode, and the light emitting element, the reflecting surface, and the like. Since the radiation in the direction orthogonal to the central axis becomes large based on the proximity of the light, a wide light distribution characteristic in the radiation range can be obtained.

  Further, even if a positional deviation between the central axis of the light emitting element and the central axis of the first reflecting mirror occurs, it is possible to prevent a difference in the brightness of the surface of the LED light.

  Moreover, even if a light source having a variation in light distribution characteristics of the light emitting element is used, it is possible to prevent a difference in brightness of the surface of the LED light by emitting light to a wide radiation range. it can.

The light-emitting diode of the present invention includes a light-emitting element mounted on a power supply unit and a sealing unit made of a light-transmitting material that seals the light-emitting element, and the sealing unit radiates from the light-emitting element. A reflecting surface for reflecting the reflected light in a direction orthogonal to or at a large angle with the central axis of the light emitting element, and a side emitting surface for emitting the light reflected by the reflecting surface from the side surface, The surface is formed with a dimension having a radius R larger than the height H in the central axis direction of the light emitting element from the light emitting surface of the light emitting element to the edge of the reflecting surface, and is close to the light emitting element. An optical system is formed.
According to such a configuration, the light emitted from the light emitting element is emitted not only in the central axis direction but also in the direction perpendicular to the central axis while reducing the thickness of the light emitting diode. can get.

In the light emitting diode, the light emitting element has a radiation intensity at an emission angle θ of the emitted light with respect to the central axis direction as I (θ), and a constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k. ,
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
By providing so that the light distribution characteristic in the side surface direction is improved, a stable light amount can be emitted in a wide range.

  In the light emitting diode, the light distribution characteristics in the lateral direction are further improved by setting k ≦ 0.6 for the constant k. In addition, even if the light distribution characteristics vary among the light emitting elements, a stable amount of light can be emitted in a wide range.

  In addition, in the above light emitting diode, when the light emitting element has a light-transmitting substrate that is transparent to light to be emitted, light reflected in the light emitting element can be emitted to the outside, and light emission The radiation efficiency of the element can be increased.

  In the light emitting diode, when the sealing means includes a light diffusing material that covers the light emitting element, light emitted from the light emitting element can be radiated in a wide range by being diffused by the light diffusing material.

  Further, in the above light emitting diode, when a phosphor is used as the light diffusion material, excitation light is emitted when the phosphor is excited by light emitted from the light emitting element, and light having a uniform brightness is emitted over a wider range. can do.

  Further, in the above light emitting diode, the sealing means is configured such that the thickness h on the light emitting surface side of the light emitting element in the central axis portion of the light emitting element is 1 mm or less, so that light is emitted from the portion directly above the light emitting element to the outside. It can radiate and prevent light emission from being lost.

  In the light emitting diode, the light emitting element is mounted at the end of the power supply means, so that it is possible to use an existing manufacturing method and apparatus excellent in mass productivity.

The LED light of the present invention includes a light emitting element mounted on a power supply means, and a sealing means made of a light-transmitting material that seals the light emitting element. A reflecting surface that reflects emitted light in a direction orthogonal to or at a large angle with the central axis of the light emitting element, and a side emitting surface that radiates light reflected by the reflecting surface from the side surface, The reflective surface has a shortest distance from the light emitting element of less than ½ of the radius R of the reflective surface, a light emitting diode that forms a proximity optical system with respect to the light emitting element, and light emitted from the light emitting diode And a reflecting mirror that reflects the light.
According to such a configuration, light emitted from the light emitting element is emitted not only in the central axis direction but also in a direction orthogonal to the central axis, and based on the proximity of the light emitting element and the reflecting surface. Since the radiation in the direction orthogonal to the central axis becomes large, the visibility is excellent, and a novel vision is imparted to the LED light, and a wide light distribution characteristic in the radiation range is obtained.

Further, the LED light of the present invention has a light emitting element mounted on the power supply means and a sealing means made of a translucent material for sealing the light emitting element, and the sealing means emits from the light emitting element. A reflecting surface for reflecting the reflected light in a direction orthogonal to or at a large angle with the central axis of the light emitting element, and a side emitting surface for emitting the light reflected by the reflecting surface from the side surface, The surface is formed with a dimension having a radius R larger than the height H in the central axis direction of the light emitting element from the light emitting surface of the light emitting element to the edge of the reflecting surface, and is close to the light emitting element. It has a light emitting diode that forms an optical system, and a reflecting mirror that reflects light emitted from the light emitting diode.
According to such a configuration, light emitted from the light emitting element is emitted not only in the central axis direction but also in a direction perpendicular to the central axis, and thus an LED light having a light distribution characteristic with a wide radiation range can be obtained.

In the LED light, the light emitting element has a radiation intensity at an emission angle θ of the emitted light with respect to the central axis direction as I (θ), and a constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k. When
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
It is characterized by being.
According to such a configuration, the light emitted from the light emitting element in the side surface direction increases, and a high-intensity LED light that hardly causes variations in light irradiation properties due to the positional accuracy with the reflecting mirror can be obtained.

  In the LED light described above, when the light emitting element has a light-transmitting substrate that shows light transmittance with respect to the emitted light, the light reflected in the light emitting element can be radiated to the outside, and the high luminance is achieved. An LED light is obtained.

  In the above LED light, when the sealing means includes a light diffusing material that covers the light emitting element, an LED light with improved visibility can be obtained by diffusing the light emitted from the light emitting element with the light diffusing material. .

  In the LED light, when the light diffusing material is a phosphor, the excitation light is emitted by exciting the phosphor by the light emitted from the light emitting element, and the brightness of the LED light can be increased. Visibility can be further improved.

Embodiments of the present invention will be described below.
In the following description, a coordinate system is defined in which the central axis of the light emitting element is the Z axis, the upper surface position of the light emitting element on the Z axis is the origin, and the origin is provided with an X axis and a Y axis orthogonal to the Z axis. . However, the Z axis is also referred to as the central axis Z.

  FIG. 1: shows the whole structure of the LED light 1 which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is AA sectional drawing of (a), (c) is ( It is an enlarged view of P part of b). The LED light 1 includes an LED 2 using a light emitting element 6 having a predetermined light distribution characteristic at the center of a disk-shaped main body, and a reflecting mirror 3 having a concentric and stepwise reflecting surface 3a around the LED 2. Have.

  The reflecting mirror 3 is formed of a transparent acrylic resin, and the reflecting surface 3a is formed by performing aluminum vapor deposition on the upper surface after forming to make a mirror surface. Each reflective surface 3a is inclined at about 45 degrees with respect to the XY plane, as shown in FIG. 5C, and reflects light incident from the X (Y) direction and radiates it in the Z direction.

  2A and 2B show the LED 2, in which FIG. 2A is a longitudinal sectional view, FIG. 2B is a plan view, and FIG. 2C is a side view. The LED 2 integrally seals the lead frames 5a and 5b, the light emitting element 6, the bonding wire 7 that electrically connects the lead frame 5b and the light emitting element 6, and the lead frames 5a and 5b and the light emitting element 6. A transparent epoxy resin 8 that stops and has an optical surface, a reflecting mirror 9 having a flat surface 9a and a reflecting surface 9b, and a part of a spherical surface centering on the light emitting element 6 are used to transmit light XY It consists of a radiation surface 10 that radiates in the direction.

  The lead frames 5a and 5b are made of a copper alloy and are provided on the XY plane via a gap for insulation, and the light emitting element 6 is mounted at the origin position of the lead frame 5a having a large area. .

  The light emitting element 6 has a rectangular parallelepiped shape, is face-up bonded to the lead frame 5a, and has an upper surface serving as a light emitting surface. Further, for the purpose of maintaining the light emission intensity of the LED 2 at a predetermined value by reducing the number of use as much as possible, a large current type (high output type) is used. The light emitting element 6 may be mounted on the lead frame 5a by flip chip bonding.

  The transparent epoxy resin 8 uses an epoxy resin having a refractive index of 1.55, and has a flat surface 9a at the center portion of the upper surface (the portion directly above the light emitting element 6). Further, the reflecting mirror 9 is formed by providing the reflecting surface 9b following the flat surface 9a. A proximity optical system is formed by molding the light emitting element 6 in close proximity to the reflecting mirror 9 and molding it integrally.

  The reflecting mirror 9 has a flat surface 9a that radiates light emitted from the light emitting element 6 in the upward direction, and a parabola with the central portion of the light emitting surface of the light emitting element 6 that is the origin of coordinates in the figure as a focal point and the X axis as the axis of symmetry. And a reflection surface 9b having a circular reflection shape obtained by rotating a part of the reflection surface around the central axis Z. It is also possible to adopt a configuration in which the reflecting mirror 9 is not provided with the flat surface 9a depending on the application.

  The reflecting mirror 9 is a first reflecting mirror that reflects the light emitted from the light emitting element 6, and the radius R of the reflecting surface 9 b is larger than that of the light emitting element 6 as shown in FIG. The relationship between the height H of the radiation surface 10 and the radius R is here formed so that most of the light emitted in the form of corners can be effectively emitted to the side surface, where H = 2.0 mm and R = 3.5 mm. Is H <R. Further, the distance (thickness of the transparent epoxy resin 8) h between the light emitting element 6 and the flat surface 9a is set to 0.5 mm so that a relatively large solid angle is formed by forming the proximity optical system. .

  FIG. 3 shows a configuration of the light-emitting element 6. From the bottom layer to the top layer, an N-type GaAs substrate 101, an N-type AlInGaP cladding layer 102, a layer 103 having a light-emitting layer, a P-type AlInGaP cladding layer 104, A P-type GaP window layer 105 is sequentially formed, and an Al bonding pad (positive electrode) 107 is formed on the P-type GaP window layer 105 via an AuZn contact 106 for ohmic contact with the window layer 105. Has been. Further, an Au alloy electrode (negative electrode) 108 is formed under the N-type GaP substrate 101. The N-type GaAs substrate 101 is opaque to the wavelength of light emitted from the light-emitting layer, and the N-type AlInGaP clad layer 102 and the P-type AlInGaP clad layer 104 are translucent.

FIG. 4 is a conceptual diagram illustrating the light distribution characteristics of the light emitting element 6. The radiant intensity radiated from the upper surface 6a and the side surface 6b (four side surfaces) of the light emitting element 6 is the sum of the radiant intensity radiated from the upper surface 6a and the radiant intensity radiated from the four side surfaces 6b. θ) is expressed by the following equation (1).
I (θ) = k · cos θ + (1−k) · sin θ (1)

  Here, k · cos θ represents the radiation intensity radiated from the upper surface 6a, and (1-k) · sin θ represents the radiation intensity radiated from the side surface 6b. θ is an angle with respect to the Z-axis in the light emitting element 6, and when the value of k changes, the distribution of the light emitted from the upper surface 6a and the light emitted from the side surface 6b changes.

  FIG. 5 shows a change in radiation intensity (Z-axis direction) when θ is changed with respect to the light-emitting element 6 having different light distribution characteristics based on the above-described formula (1). The angle definition for 6 is shown. (B) is a state in which 100% light is emitted from the upper surface 6a at k = 1 (upper 100%), and (c) is 80% from the upper surface 6a and 20% from the side surfaces 6b at 20 k. % Light is emitted (up to 80%). Further, (d) is a state in which 60% of light is emitted from the upper surface 6a and 40% from the side surface 6b (upper 60%) at k = 0.6.

  The light emitting element 6 has a characteristic that the ratio of light emitted from the upper surface of the layer 103 having the light emitting layer is increased from the upper surface because the N-type GaAs substrate 101 becomes a black absorber with respect to the light emission color. K = 0.8. That is, 80% of light is emitted from the upper surface 6a, and 5% of light is emitted from each of the side surfaces 6b. In order to obtain such a desired light distribution characteristic, the thickness of the epitaxial layer and the shape of the light emitting element 6 are adjusted.

  In the light-emitting element 6 having the light distribution characteristic shown in FIG. 5B, light is emitted from the upper surface 6a, and the radiation intensity decreases as θ increases, and is almost zero at θ = 90 °. Further, the light emitting element 6 having the light distribution characteristic of (c) has a structure in which light is also emitted from the side surface 6b, and the radiation intensity at θ = 0 is smaller than that of the light emitting element shown in (b). Even at 90 °, the radiation intensity does not become zero, and light is emitted in the XY directions. Further, in the light emitting element 6 having the light distribution characteristic of (d), the amount of light radiated from the side surface 6b is larger than that of the light emitting element 6 shown in (c), so that the radiation intensity at θ = 0 becomes small. However, the decrease of the radiation intensity due to the change of θ is smaller than that of (b) and (c), and the radiation intensity does not become 0 even at θ = 90 °, and the light is emitted in the XY direction. Is emitted.

  The light distribution characteristics of the LED 2 are the light distribution characteristics of the light emitting element 6 described above, the positional accuracy of the optical surface composed of the light emitting element 6, the flat surface 9a, the reflecting surface 9b, and the radiation surface 10, and the lead frame 5a of the light emitting element 6. Depends on the mounting position accuracy and the setting position accuracy with respect to the mold when the lead frame 5a and the optical surface are integrally molded. In order to prevent the light distribution in the θ direction shown in FIG. 2B from being biased, the uniformity of the light emitted in the circumferential direction (360 °) of the radiation surface 10 around the Z axis is required. However, if there is a positional shift between the light emitting element 6 and the optical surface, uneven light distribution in the θ direction occurs according to the shift amount. In particular, the proximity optical system of the LED 2 according to the present invention has a structural characteristic that uneven light distribution is likely to occur due to the occurrence of a slight positional deviation.

  FIG. 6 shows light emitted directly upward from the LED 2 and light reaching the reflecting surface 3a due to a change in light distribution characteristics when the center axis of the light emitting element 6 in the LED 2 is displaced in the X-axis direction with respect to the optical surface. When the light emitting element 6 having a GaAs substrate is used, if the amount of deviation occurs in the X-axis direction during production, the effective radiation efficiency ratio decreases. In the figure, it is clearly reduced particularly at 0.3 mm or more.

  FIGS. 7A and 7B show the observation conditions for the amount of light emitted from the LED 2, and are diagrams represented by Φij obtained by dividing the entire direction around the LED 2 into 32 parts. As shown in (a), 360 [deg.] Around the Z axis of LED2 is divided into eight (j = 1-8), and as shown in (b), 0 [deg.]-20 [deg.] With respect to the Z axis. Angle range (i = 1), angle range from 20 ° to 60 ° (i = 2), angle range from 60 ° to 100 ° (i = 3), angle range from 100 ° to 180 ° ( i = 4), and the amount of light emitted from the LED 2 to these regions will be described below. Here, the angle range region from 0 ° to 20 ° with respect to the Z axis is directly emitted from the LED 2 to the vicinity of the Z axis, and the angle range region from 60 ° to 100 ° with respect to the Z axis is reflected from the LED 2. It is assumed that the light is radiated to the mirror 3 and then reflected by the reflecting mirror 3 in the direction near the Z-axis and radiated outside.

  FIG. 8A shows the total light amount bias of the LED 2 when the light emitting element 6 having the light distribution characteristic of 100% above is used under the observation conditions shown in FIG. 7, and the total light amount bias is 0.0 in the X direction. Is obtained by setting conditions under which six steps of deviation amount from 0.5 mm to 0.5 mm are generated, and the total light quantity deviation in each direction is shown by a line. As the amount of deviation increases, the total light quantity deviation increases. FIG. 5B shows the total light amount bias of the LED 2 when the light emitting element 6 having the upper 80% light distribution characteristic is used. Since the light emitting element 6 emits light from the side surface 6b, the total light amount is shown. The bias has been improved.

  Thus, as the amount of light emitted from the lateral direction of the light emitting element 6 increases, the total light amount deviation in the effective radiation range due to the positional deviation between the light emitting element 6 and the optical surface becomes smaller. Therefore, if the light emitting element 6 having a light distribution characteristic of k = 0.8 or less is used, the position of the light emitting element 6 mounted on the lead frame 5a is 0.1 mm from the Z axis in the X axis (or Y axis) direction. Even if the dimensional deviation is within the range, it can be compensated by the light distribution characteristic of the light emitting element 6, so that the total light quantity deviation in the effective radiation range is almost eliminated and there is no visual influence.

  The above-described LED 2 can be manufactured by, for example, a transfer mold method. The manufacturing method by the transfer mold method will be described below. Here, the light emitting element 6 having a light distribution characteristic of k = 0.8 is used. First, the light emitting element 6 is face-up bonded to the lead frame 5a formed by pressing. Next, the Al bonding pad 107 of the light emitting element 6 and the lead frame 5 b are electrically connected by the bonding wire 7. Next, the lead frames 5a and 5b on which the light emitting element 6 is mounted are placed on a mold that can be divided into upper and lower parts, and are positioned by sandwiching them from above and below. Next, the transparent epoxy resin 8 is poured into the mold. Next, the transparent epoxy resin 8 is cured at 160 ° C. for 5 minutes. Next, the mold 2 is separated into upper and lower parts and the LED 2 in which the transparent epoxy resin 8 is cured is taken out. In order to improve the releasability between the mold and the transparent epoxy resin 8, the transparent epoxy resin 8 containing a release component is used.

Next, the operation of the LED light 1 will be described.
When a power switch (not shown) of the LED light 1 is turned on by an operator, a power supply unit (not shown) applies a voltage to the lead frames 5a and 5b. The light emitting element 6 emits light based on application of voltage. The light radiated from the light emitting element 6 and radiated immediately above along the Z axis is radiated from the flat surface 9a to the outside of the transparent epoxy resin 8, and is radiated outside. Further, 50 to 60% of the light radiated from the light emitting element 6 reaches the reflecting surface 9b having a solid angle of about 2.7 straad with respect to the light emitting element 6, and is radiated from the light emitting element 6 to the Z axis. The light radiated in the substantially horizontal direction reaches the radiation surface 10 directly, and is directly radiated from the radiation surface 10 in a direction substantially parallel to the XY plane.

  The light emitted from the LED 2 substantially parallel to the XY plane is reflected by the reflecting surface 3a of the reflecting mirror 3 in the substantially Z-axis direction and is emitted to the outside.

  According to the LED light 1 of the first embodiment described above, k in the light distribution characteristic I (θ) = k · cos θ + (1−k) · sin θ for the light emitting element 6 of the LED 2 constituting the proximity optical system is obtained. Since the light emitting element 6 and the optical surface are integrally formed by the transfer molding method, the light in the X-axis direction radiated from the LED 2 and reaching the reflecting mirror 3 is set to 0.8 or less. There is almost no deviation of the total amount of light in the effective radiation range, and the reflector 3 can radiate almost uniformly in the Z-axis direction. Thereby, it is possible to obtain a thin lamp having a large reflecting mirror surface, no difference in surface brightness, and having a good appearance. As a result, when applied to the taillights and brake lights of automobiles, it is possible to improve the visibility of light from the lateral direction as well as directly behind the automobile.

  In the above-described LED light 1, the configuration using the LED 2 using the light emitting element 6 having the light distribution characteristic of k = 0.8 has been described as an example, but has the light distribution characteristic of k = 0.8 or less. If the light emitting element 6 is used, the total light amount deviation in the effective radiation range due to the positional deviation between the light emitting element 6 and the optical surface can be reduced to a level that does not cause a problem in practice.

  Further, in the manufacture of the LED 2 by the transfer mold method, the transparent epoxy resin 8 is injected into the mold while the lead frames 5a and 5b are sandwiched between the molds, so that the positioning accuracy between the light emitting element 6 and the optical surface is ± 0. It is possible to realize with high accuracy of 1 mm, and it is stable by preventing variation in light distribution characteristics due to individual differences of LEDs 2 even in a proximity optical system configured using a light emitting element 6 with k = 0.8. The LED light 1 having the quality as described above can be provided.

  Moreover, although the structure using the transparent epoxy resin 8 was demonstrated as a translucent material which seals the light emitting element 6, even if it is another translucent material with the same translucency and another optical characteristic, Good. Moreover, although the transparent acrylic resin is used as a resin material which comprises the reflective mirror 3, other materials can also be used including other transparent resin. Further, the configuration, shape, quantity, material, size, connection relationship, and the like of other parts of the LED light are not limited to the embodiment.

  Moreover, although the reflective surface 9b was demonstrated as what applied the total reflection of resin, without performing a mirror surface process, the mirror surface process by metal vapor deposition etc. may be performed.

  9A and 9B show an LED 2a according to a second embodiment of the present invention, in which FIG. 9A is a plan view of the LED 2a viewed from the Z direction, and FIG. 9B is a longitudinal sectional view of the portion of the light emitting element 6 in FIG. It is. This LED 2a is made of a GaP substrate AlInGaP using an N-type GaP substrate having translucency, and is composed of a light emitting element 6 having an upper 60% (k = 0.6) light distribution characteristic, a copper alloy, and a resin. The lead frame 5b is formed by bending the sealing portion, and the light emitting element 6 is mounted on the tip of the lead frame 5c. In addition, since the same reference numerals are given to portions having the same configuration as that of the first embodiment, a duplicate description is omitted.

  FIG. 10 shows the total light amount deviation of the LED 2 when the light emitting element 6 having the light distribution characteristic of k = 0.6 is used, and the amount of light emitted from the side surface 6b of the light emitting element 6 is increased. Compared to the case where the light emitting element 6 having the light distribution characteristic of k = 0.8 is used, even when X = 0.4 mm, the light distribution deviation is within ± 20%, and the total light quantity deviation is improved. In the light emitting element 6 with k = 0.6, a material that shows light transmittance with respect to the emission color such as GaP is used for the substrate so as to increase the amount of radiation from the side surface 6b based on reflection inside the light emitting element 6. Form.

  The LED 2a can be manufactured by, for example, a casting mold method. The manufacturing method by the casting mold method will be described below. Here, the light emitting element 6 having a light distribution characteristic of k = 0.6 is used. First, the lead frames 5b and 5c are punched by pressing. At this time, the lead frames 5b and 5c are not divided, and a plurality of rear ends are connected by leads. Next, the rear end connected by the lead is fixed to the support member. Next, the lead frames 5b and 5c are bent into a desired shape. Next, the light emitting element 6 is face-up bonded to the tip of the lead frame 5c. Next, the Al bonding pad 107 of the light emitting element 6 and the lead frame 5 b are electrically connected by the bonding wire 7. Next, the lead frames 5b and 5c are moved onto the casting for molding. Next, a transparent epoxy resin 8 is injected into the casting. Next, the lead frames 5b and 5c are immersed in the casting into which the transparent epoxy resin 8 is injected. Next, the space in which the casting and lead frames 5b and 5c are arranged is evacuated, and air bubbles are removed from the transparent epoxy resin 8. Next, the transparent epoxy resin 8 is cured at 120 ° C. for 60 minutes. Next, the LED 2a in which the transparent epoxy resin 8 is cured is taken out from the casting.

  According to the LED 2a of the second embodiment described above, the light-emitting element 6 is configured to use a light-transmitting N-type GaP substrate and have a light distribution characteristic of k = 0.6. A wider range of light distribution characteristics can be obtained than the LED 2 using the light emitting element 6 having an N-type GaAs substrate. Therefore, even if a positional deviation between the light emitting element 6 and the optical surface occurs, if the deviation is small, the total light quantity deviation in the effective radiation range can be suppressed to a level that does not cause a problem in practice.

  Further, in the casting mold method, since the tips (free ends) of the lead frames 5b and 5c are not supported and restrained by casting, the positioning accuracy between the light emitting element 6 and the optical surface is ± 0.2 mm, which is based on the manufacturing by the transfer mold method. descend. In particular, it is difficult to realize high positioning accuracy in the case where the light emitting element 6 is mounted on the plate thickness portion at the tip of the flat lead frame. However, productivity can be improved by increasing the allowable range of positioning accuracy, and the mass productivity is excellent. When the transparent epoxy resin 8 is cured for a long time, the thermal stress unevenness is reduced, and the lead frames 5b, 5c and the transparent epoxy resin 8 are less likely to be peeled off. In addition, it is possible to stabilize the light distribution characteristics by selecting the manufacturing process management and the light distribution characteristics of the light emitting element 6.

  11A and 11B show an LED 2b according to a third embodiment of the present invention, in which FIG. 11A is a plan view of the LED 2b viewed from the Z direction, and FIG. 11B is a longitudinal sectional view of a portion of the light emitting element 6 in FIG. It is. This LED 2b is made of a GaP substrate AlInGaP using an N-type GaP substrate having translucency, and is a light-emitting element 6 having a light distribution characteristic of 40% (k = 0.4) and a flat plate made of a copper alloy. Shaped lead frames 5b and 5d. In addition, since the same reference numerals are given to portions having the same configuration as those of the first and second embodiments, redundant description is omitted.

  The light-emitting element 6 with k = 0.4 is formed in a smaller size (for example, 0.3 mm square) than the light-emitting element 6 with k = 0.6, thereby reducing absorption loss inside the light-emitting element. Thus, the amount of radiation from the side surface 6b is further increased.

  The light emitting element 6 is mounted at the tip of a lead frame 5c punched out by press working.

  According to the LED 2b of the third embodiment described above, since the light emitting element 6 is mounted at the tip of the lead frame 5d, the lead frames 5b, 5d are excellent in mass productivity while suppressing the total light amount deviation in the effective radiation range. And the transparent epoxy resin 8 can be reduced in contact area, which can make peeling more difficult. In addition, work steps such as bending of the lead frames 5b and 5d can be made unnecessary, so that productivity can be improved.

  Further, since a light-transmitting N-type GaP substrate is used for the light-emitting element 6, a wide range of light distribution as compared with the LED 2 using the light-emitting element 6 having an N-type GaAs substrate as in the second embodiment. Characteristics are obtained. Therefore, even if a positional deviation between the light emitting element 6 and the optical surface occurs, if the deviation is small, the total light quantity deviation in the effective radiation range can be suppressed to a level that does not cause a problem in practice.

  FIG. 12 shows an LED 2c according to a fourth embodiment of the present invention, in which a light emitting element 6 made of an Al2O3 substrate GaN and lead frames 5b and 5d made of a copper alloy and formed by bending a resin sealing portion. And a transparent epoxy resin 8 having an optical surface, and the light emitting element 6 is mounted on the tip of the lead frame 5d. The light emitting element 6 is sealed in a hemispherical shape with a sealing resin 8s containing a phosphor. In the figure, transparent epoxy resin 8 is shown as a transparent member. In addition, since the same reference numerals are given to the portions having the same configurations as those of the first, second, and third embodiments, redundant description is omitted.

  According to the LED 2c of the fourth embodiment described above, since the light emitting element 6 mounted on the tip of the lead frame 5d is hemispherically sealed with the sealing resin 8s, it does not have a wide range of light distribution characteristics. Even when the light emitting element 6 is used, the light can be diffused by the excitation light emitted from the phosphor, so that the light distribution characteristic can be made suitable for the proximity optical system of the present invention.

  For example, Ce: YAG (yttrium, aluminum, garnet) can be used as the phosphor. In order to improve the light distribution characteristics, a similar effect can be obtained by mixing a light diffusing material in the sealing resin 8s instead of the phosphor and diffusing the light with the light diffusing material. For example, titanium oxide, alumina, or SiO 2 can be used as the light diffusing material.

  In each of the above-described embodiments, the configuration using a GaAs-based substrate for the light-emitting element 6 has been described. However, a GaP substrate AlInGaP-based or GaN-based substrate can be used depending on the light distribution characteristics. In addition, a substrate having a light-transmitting property or a light-transmitting material can be selectively used with respect to the emission wavelength, and the light-emitting element 6 applicable to the LED light 1 is not particularly limited.

  Further, the light emitting diode has been described as sealing the light emitting element and molding the reflection surface and the side reflection surface, but the present invention is not limited to this, for example, a reflection formed separately with a translucent resin. A proximity optical system for the light emitting element can also be formed by attaching the surface and the side reflecting surface together with the light emitting element by sealing with a light transmissive material.

  Further, in each of the above-described embodiments, the reflecting mirror 9 has a circular reflection shape in which a part of a parabola with the origin of the light emitting element 6 as a focal point and the X axis as a symmetry axis is rotated around the central axis Z. The radiation surface 10 is described as having a shape that forms a part of a spherical surface centered on the light emitting element 6. However, the light emitted from the light emitting element 6 is formed at a large angle with respect to the central axis Z. The shape is not particularly limited as long as the shape can radiate substantially in the side surface direction. In particular, under the condition where the shape of the transparent epoxy resin 8 shown in each embodiment and the relationship of H <R are satisfied, the reflecting mirror 9 is close to the light emitting element 6, and the LED of the LED due to the positional accuracy of the optical system is used. The same effect can be obtained with respect to the stability of the light distribution characteristics. Even when the relationship of H <R is not satisfied, the same effect can be obtained when h <1 mm. Further, the reflection surface 9b has stable light distribution characteristics even when the proximity optical system is formed such that the shortest distance from the light emitting element 6 is less than 1/2 with respect to the radius R shown in FIG. Can increase the sex.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the whole structure of the LED light using LED which concerns on 1st Embodiment, (a) is a top view, (b) is AA sectional drawing of (a), (c) is (b) FIG. It is a figure which shows the structure of LED which concerns on 1st Embodiment, (a) is sectional drawing, (b) is a top view, (c) is a side view which shows the size of each part. It is a side view which shows the structure of the light emitting element which concerns on 1st Embodiment. It is a radiation conceptual diagram of the light radiated | emitted from the upper surface and side surface of the light emitting element which concerns on 1st Embodiment. The light distribution characteristic curve of the light emitting element which concerns on 1st Embodiment is shown, (a) is explanatory drawing of the angle with respect to the Z-axis of a light emitting element, (b) is a characteristic which shows the change of the radiation intensity when k = 1. FIG. 4C is a characteristic diagram showing a change in radiation intensity when k = 0.8, and FIG. 4D is a characteristic chart showing a change in radiation intensity when k = 0.6. The relationship figure of the effective radiation efficiency ratio of the LED which concerns on 1st Embodiment, and a X-axis direction shift | offset | difference. (A) And (b) is a conceptual diagram which shows the observation conditions of the light quantity radiated | emitted from LED. The total light quantity deviation of the effective radiation range of LED which concerns on 1st Embodiment is shown, (a) is a characteristic view which shows the total light quantity bias of the effective radiation range in LED using the light emitting element whose light distribution characteristic is 100% above (B) is a characteristic figure which shows the total light quantity deviation of the effective radiation | emission range in LED using the upper 80% light emitting element. It is a figure which shows the whole structure of the LED light using LED which concerns on 2nd Embodiment, (a) is a top view, (b) is a longitudinal cross-sectional view of the light emitting element part of (a). It is a characteristic view which shows the total light quantity deviation of the effective radiation range in LED using the light emitting element which has the light distribution characteristic of 60% (k = 0.6) according to 2nd Embodiment. It is a figure which shows the whole structure of the LED light using LED which concerns on 3rd Embodiment, (a) is a top view, (b) is a longitudinal cross-sectional view of the light emitting element part of (a). It is a longitudinal cross-sectional view of the LED light using LED which concerns on 4th Embodiment. It is sectional drawing which shows the structure of the conventional LED light.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, LED light 3, Reflective mirror 3a, Reflective surface 5a, 5b, 5c, 5d, Lead frame 6, Light emitting element 6a, Upper surface 6b, Side surface 7, Bonding wire 8, Transparent epoxy resin 8s, Sealing resin 9, Reflective mirror 9a, flat surface 9b, reflecting surface 10, emitting surface 101, N-type GaAs substrate 102, N-type AlInGaP cladding layer 103, layer 104 having a light emitting layer, P-type AlInGaP cladding layer 105, P-type GaP window layer 106, AuZn contact 107, Al bonding pad 108, Au alloy electrode 202, light emitting elements 203a and 203b, lead frame 204, bonding wire 205, transparent epoxy resin 206, reflecting mirror 207, Fresnel lens 209, resin lens 209a, interface

Claims (9)

A light emitting device mounted on the power supply means;
Sealing means by a translucent material for sealing the light emitting element,
The sealing means reflects the light emitted from the light emitting element in a direction perpendicular to the central axis of the light emitting element or in a direction forming a large angle with the central axis, and reflects the light reflected by the reflective surface from the side surface. A side emission surface that emits light, and the reflective surface has a shortest distance to the light emitting element of less than ½ of the radius R of the reflective surface, and forms a proximity optical system for the light emitting element,
The light emitting element has a radiation intensity at an emission angle θ of the emitted light with respect to the central axis direction as I (θ), and a constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k,
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
A light emitting diode characterized by the above. A light emitting device mounted on the power supply means;
Sealing means by a translucent material for sealing the light emitting element,
The sealing means reflects the light emitted from the light emitting element in a direction orthogonal to the central axis of the light emitting element or in a direction forming a large angle with the central axis, and the light reflected by the reflective surface is emitted from the side surface. And the reflective surface has a dimension in which the radius R is larger than the height H in the central axis direction of the light emitting element from the light emitting surface of the light emitting element to the edge of the reflective surface. Formed to form a proximity optical system for the light emitting element,
The light emitting element has a radiation intensity at an emission angle θ of the emitted light with respect to the central axis direction as I (θ), and a constant determined by the radiation intensity according to the emission angle θ of the light emitting element is k,
I (θ) = k · cos θ + (1−k) · sin θ
(However, k ≦ 0.8)
A light emitting diode characterized by the above.   The light-emitting diode according to claim 1, wherein the light-emitting element satisfies k ≦ 0.6 with respect to the constant k.   The light-emitting diode according to claim 1, wherein the light-emitting element includes a light-transmitting substrate that exhibits light transmission with respect to emitted light.   The light emitting diode according to claim 1, wherein the sealing unit includes a light diffusing material that covers the light emitting element.   6. The light emitting diode according to claim 5, wherein the light diffusion material is a phosphor.   The thickness of the light emission surface side of the said light emitting element in the center axis | shaft part of the said light emitting element is formed in the said sealing means to 1 mm or less, The any one of Claim 1 to 6 characterized by the above-mentioned. Light emitting diode.   The light emitting diode according to claim 1, wherein the light emitting element is mounted on an end of the power supply unit. The light emitting diode according to any one of claims 1 to 8,
An LED light comprising: a reflecting mirror that reflects light emitted from the light emitting diode.

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