JP2551176B2 - Light emitting diode lamp - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement of a light emitting diode lamp mainly used as a light source such as a dial provided outdoors.

[Conventional technology]

Conventionally, in a light emitting diode lamp in which a plurality of light emitting diodes are arranged, in order to effectively radiate light forward, light emitting diode lamps having various structures have been devised. FIG. 14 is a schematic front view of a conventional light-emitting diode lamp, FIG. 15 is a schematic structural sectional view when a plurality of light-emitting diode lamps are vertically arranged, and FIG. 16 is light emission used in the light-emitting diode lamp. FIG. 17 is a schematic front view of the diode, and FIG. 17 is a schematic structural sectional view of the light emitting diode. In FIGS. 14 to 17, 51 is a light emitting diode, 52 is an eaves, 53 is a holding case, 61 is a light emitting element, 6
2, 63 is a lead frame, 64 is a wire, 65 is a light transmissive material, 66 is a concave reflection surface, and 67 is a radiation surface.

The light emitting element 61 of the light emitting diode 51 is mounted on one lead frame 62, and is electrically connected to the other lead frame 63 by a wire 64. Also, the light emitting element
61, the tip of the lead frame 62.63 and the wire 64 are integrally sealed with a light transmissive material 65. Light emitting element 61
A concave reflecting surface 66 is formed on the side opposite to the light emitting surface of, and a radiation surface 67 is formed on the back side of the light emitting element 61. The concave reflecting surface 66 is formed by mirror-finishing one surface of the light transmissive material 65 by plating, metal deposition or the like. It should be noted that the lead frames 62 and 63 need to be insulated in order to prevent a short circuit between the two lead frames 62 and 63 during mirror finishing.

A light emitting diode lamp is formed by attaching or sealing the light emitting diode 51 to the holding case 53. Further, an eaves 52 is provided above the light emitting diode lamp within a range of the light emitted from the light emitting element 61 so as not to hinder the distribution of light in a necessary direction. Then, for example, the light emitting diode lamp is configured by arranging three light emitting diodes each having a diameter of 5 mm vertically and horizontally at intervals of 6.5 mm, and a plurality of the light emitting diode lamps are vertically and horizontally arranged at intervals of 25 mm.

In the light emitting diode lamp configured as described above, the light emitted from the light emitting element 61 of the light emitting diode 51 is reflected by the concave reflecting surface 66 and emitted from the emitting surface 67 to the outside. As described above, the light emitted by the light emitting element 61 is once reflected by the concave reflecting surface 66 and then emitted to the outside, whereby substantially the entire luminous flux of the light emitted by the light emitting element 61 can be emitted forward. Further, since the light emitting diode lamp is provided with the eaves 52, it is possible to prevent external light, particularly sunlight, from entering the emitting surface 67 (that is, the concave reflecting surface 66) of the light emitting diode 51.

[Problems to be Solved by the Invention]

However, in such a conventional light emitting diode lamp, of the light emitted from the light emitting element 61 of the light emitting diode 51, the light emitted to the outside in the forward and upward direction is blocked by the eaves 52 and becomes useless light. Therefore, the conventional light emitting diode lamp has a problem that the light emission efficiency is low.

Further, in the conventional light emitting diode lamp, the length of the eaves 52 is set so that the light emitted downward from the front of the light emitted by the light emitting element 61 is not blocked by the eaves 52 of another light emitting diode lamp. Need to be restricted. In particular, the concave reflecting surface 66 with a large downward emission angle
When using, the size of the eaves 52 must be shortened. On the other hand, when the eaves 52 is shortened, the amount of external light that enters the radiation surface 67 (that is, the concave anti-slope surface 66) and is reflected by the concave reflection surface 66 increases. For this reason, the contrast between when the light emitting diode lamp is turned on and when it is turned off is significantly reduced.

The present invention has been made based on the above circumstances,
An object of the present invention is to provide a light emitting diode lamp capable of improving the radiation efficiency of light in a predetermined direction and reducing the influence of reflection by external light.

[Means for solving the problem]

A light emitting diode lamp according to the present invention for achieving the above object, a light emitting element, a lead portion for supplying electric power to the light emitting element, and a concave reflecting surface provided facing the light emitting surface of the light emitting element. A light-emitting diode lamp having a light-emitting diode having a light-emitting diode and having an eaves formed on the light-emitting diode to prevent external light from entering the concave reflection surface, when the concave reflection surface is viewed from the front. The substantially lower half surface of the light-emitting element reflects the light emitted from the light-emitting element so as to be substantially parallel to the central axis of the concave reflection surface, and the substantially upper half surface when the concave reflection surface is viewed from the front is the light-emitting element. It is characterized in that it is formed so as to reflect the light emitted by.

A plurality of the light emitting diodes may be arranged and the eaves may be provided corresponding to each of the light emitting diodes.

Further, of the eaves, the eaves provided on the upper portion may be formed to have a longer dimension than other eaves.

[Action]

With the above structure, the light emitting diode lamp according to the present invention reflects the light emitted by the light emitting element by the concave reflecting surface in a direction substantially parallel to or downward from the central axis of the concave reflecting surface. Can be prevented from colliding with the eaves and radiated in a direction other than the predetermined direction, and the light emission efficiency in the predetermined direction can be improved. Further, when a plurality of light emitting diode lamps according to the present invention are arranged side by side in the vertical direction, in the present light emitting diode lamp, it is only the upper half surface of the concave reflecting surface that radiates downward in the front, When the emission angle is the same as the conventional lamp,
The eaves can be formed longer than conventional lamps,
Radiating surface (that is, concave reflecting surface) compared to conventional lamps
The amount of external light incident on can be reduced.

By arranging a plurality of light emitting diodes and providing eaves corresponding to the respective light emitting diodes, it is possible to reduce the amount of external light incident on the concave reflecting surface due to the eaves having shorter dimensions. Also, for example, when a plurality of light emitting diode lamps are arranged and used on an outdoor dial or the like, the eaves can be shortened, so that the mounting interval can be narrowed and arranged at a high density. . Further, if the eaves are short, heat generated by the light emitting diodes is easily transferred to the eaves, and thus the influence of snow on the eaves can be reduced.

Further, of the eaves, by providing the eaves provided at the upper portion with a length longer than that of the other eaves, it is possible to prevent external light having a smaller incident angle from entering the concave reflecting surface.

〔Example〕

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is a schematic front view of a light emitting diode lamp which is a first embodiment of the present invention, FIG. 2 is a schematic structural sectional view when a plurality of the light emitting diode lamps are vertically arranged, and FIG. 3 is a light emitting diode thereof. FIG. 4 is a schematic front view of a light emitting diode used in a lamp, FIG. 4 is a schematic structural sectional view of the light emitting diode, and the light emitting diode lamps shown in FIGS. 1 and 2 are a light emitting diode 1, an eaves 2,
It is composed of a holding case 3. The light emitting diode 1 shown in FIGS. 3 and 4 includes a light emitting element 11 and a lead frame 1.
2, 13, wires 14, a light transmissive material 15, a concave reflecting surface 16, and a radiation surface 17. The z-axis is the central axis direction of the concave reflecting surface 16, the x-axis is the horizontal direction perpendicular to the z-axis in the plane including the edge of the concave reflecting surface 16, and the y-axis is the edge of the concave reflecting surface 16. It is a direction perpendicular to the z-axis and the x-axis in the plane including the plane. A dotted line with an arrow indicates light emitted from the light emitting diode at the maximum emission angle, and a solid line with an arrow indicates incident external light.

The light emitting element 11 is mounted on one lead frame 12 and is electrically connected to the other lead frame 13 by a wire 14. In addition, the light emitting element 11, the lead frame
The tip portions of the wires 12 and 13 and the wire 14 are integrally sealed with a light transmissive material 15. A concave reflecting surface 16 is formed on the side facing the light emitting surface of the light emitting element 11, and a radiation surface 17 is formed on the back side of the light emitting element 11. The concave reflecting surface 16 is obtained by mirror-finishing one surface of the light-transmitting material 15 by plating, metal deposition, or the like, and prevents short-circuiting between the two lead frames 12 and 13 when mirror-finishing. For leadframes 12,
13 needs to be insulated. The concave reflecting surface 16 is x
In order to widen the radiation angle in the axial direction, a plane cut perpendicular to the z-axis is formed into a substantially elliptical shape having a long axis in the x-axis and a short axis in the y-axis, and radiation in the y-axis direction. In order to narrow the angle, the inclination angle α of the edge in the yz plane is formed to be about 45 °. And the light emitting element
11 is arranged at a position where its center is slightly shifted from the z axis to the lower side of the y axis. Thereby, the substantially lower half surface of the concave reflecting surface 6 when viewed from the front reflects the light emitted from the light emitting element as light substantially parallel to the central axis of the concave reflecting surface 6, and the substantially upper half surface thereof is The light emitted from the light emitting element is emitted in a substantially downward direction.

The light emitting diode lamp uses the light emitting diode 1
For example, it is formed by attaching to the holding case 3 or by sealing. Further, an eaves 2 is provided above the light emitting diode lamp within a range of the light emitted from the light emitting element 11 so as not to hinder the light distribution in a necessary direction. Then, for example, in an outdoor dial or the like, a plurality of light emitting diode lamps in which three light emitting diodes 1 are arranged vertically and horizontally are arranged vertically and horizontally as necessary.

In the light-emitting diode lamp configured as described above, of the light emitted by the light-emitting element 11, the light reflected by the lower half surface of the concave reflecting surface 16 is radiated to the outside substantially parallel to the z-axis, and the concave surface The light reflected by the substantially upper half surface of the curved reflecting surface 16 is emitted downward in the external direction. As described above, in the light emitting diode lamp according to the present embodiment, the amount of light externally emitted in the upward direction is small, so that the ratio of the light that collides with the eaves 2 and is emitted in a direction other than the predetermined direction is smaller than that of the conventional one. , The light emission efficiency in the predetermined direction is improved. Further, when a plurality of light emitting diode lamps of the present embodiment are arranged side by side in the vertical direction, in the light emitting diode lamp of the present embodiment, only the substantially upper half surface of the concave reflecting surface 16 radiates downward in the front direction. Therefore, when the radiation angle is the same as that of the conventional lamp, the size of the eaves 2 can be made longer than that of the conventional lamp. Further, this makes it possible to reduce the amount of external light incident on the concave reflecting surface 16.

Next, the influence of the reflection of external light in the light emitting diode lamp of this embodiment will be quantitatively considered.

Each light-emitting diode lamp is arranged so that the light emitted from the light-emitting diode downward at the maximum angle θ passes through the tip of the eaves of the light-emitting diode lamp located directly below it. If the distance between the position on the surface and the eaves in the y-axis direction is D, there is a relationship of D / A = tan θ. Here, A is the length of the eaves. Also, if the minimum angle at which the outside light passing through the tip of the eaves does not enter the emitting surface 17 is φ, and the distance between the eaves and the lower edge of the emitting surface 17 in the y-axis direction is W, W / A = tan φ There is. From the above two equations, we obtain the relational expression tanφ = W / D · tanθ. Figure 5 shows this relationship.
7 is a graph showing the relationship between W / D and incident angle φ with respect to the radiation angle θ.

In the light emitting diode lamp of this embodiment, D = 11 mm, W
= 17 mm, W / D≈1.5. According to this figure, for example, when the radiation angle θ is 10 degrees or 20 degrees, each of them is about 15
Outside light with an incident angle φ of about 29 degrees or more
Therefore, it cannot be incident on the radiation surface 17. Only when the incident angle φ of the external light is equal to or less than the above angle, the external light is incident on the emitting surface 17. Most of the external light incident on the emitting surface 17 is reflected by the concave reflecting surface 16 and emitted to the outside.

By the way, in the conventional light emitting diode lamp shown in FIGS. 14 and 15, D = 8 mm, W = 18 mm, and W / D = 2.25. In this case, from FIG. 5, when the radiation angle θ is 10 degrees or 20 degrees, the incident angles are about 22 degrees and about 20 degrees, respectively.
External light of 39 degrees or less enters the emitting surface 17.

Thus, in the light emitting diode lamp of this embodiment,
When a plurality of light emitting diode lamps are arranged in the vertical direction, it is possible to prevent the incidence of external light having a smaller incident angle than that of the conventional light emitting diode lamp. Therefore, the light emitting diode lamp of the present embodiment can greatly improve the contrast between the time when the light emitting diode lamp is turned on and the time when the light emitting diode lamp is turned off even when used outdoors during the daytime.

FIG. 6 is a schematic front view of a light emitting diode lamp which is a second embodiment of the present invention, and FIG. 7 is a schematic structural sectional view when a plurality of the light emitting diode lamps are arranged in the vertical direction.
In the present embodiment and the embodiments described below, those having the same functions as those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The second embodiment of the present invention is different from the first embodiment described above.
The eaves 2 is formed corresponding to each light emitting diode 1.

With the above configuration, in this embodiment, D = 2.1 m
m, W = 2.5 mm, W / D≈1.2. According to FIG.
When the emission angle θ is 10 degrees or 20 degrees, the incident angle φ
However, external light of about 12 degrees and about 24 degrees or more cannot enter the emitting surface 17. Therefore, in the light emitting diode lamp of this embodiment, the amount of external light incident on the emitting surface 17 (that is, the concave reflecting surface 16) can be reduced more than in the case of the light emitting diode lamp of the first embodiment. it can.

In addition, in this embodiment, the space D can be reduced by forming the eaves 2 on each light emitting diode 1. That is, it is possible to arrange the LED lamps at a high density by narrowing the space between the light emitting diode lamps in the vertical direction. Moreover, since W is shortened, the length of the eaves 2 can be shortened. Furthermore, since the eaves 2 is short, the heat from the light emitting diode lamp is easily transferred to the tip of the eaves 2,
There is also an effect that it is possible to reduce snow accumulation on the eaves 2 at the time of snowfall. Other functions and effects are similar to those of the first embodiment.

FIG. 8 is a schematic front view of a light emitting diode lamp which is a third embodiment of the present invention, and FIG. 9 is a schematic structural sectional view when a plurality of the light emitting diode lamps are vertically arranged.
In this embodiment, the eaves 2a provided corresponding to the light emitting diodes arranged at the uppermost stage are formed to be longer than the eaves 2b provided elsewhere. Other configurations are the same as in the first embodiment.

When a plurality of light emitting diode lamps are vertically arranged, the distance between the light emitting diodes is usually smaller than the distance M between the light emitting diodes in the light emitting diode lamps as shown in FIG. The interval N is larger. Therefore, the eaves 2a at the uppermost stage of each light emitting diode lamp can be increased in size within a range that does not hinder the emission of the light emitting diode at the lowest stage of the immediately uppermost light emitting diode lamp. As a result, in the light emitting diode lamp according to the present embodiment, the amount of external light incident on the emitting surface 17 (that is, the concave reflecting surface 16) can be further reduced as compared with the light emitting diode lamps according to the first and second embodiments. You can Other functions and effects are similar to those of the first embodiment. Incidentally, in the above-mentioned first to third embodiments,
The concave reflection surface is formed such that a cut surface by a plane perpendicular to the z axis has a substantially elliptical shape having a long axis on the x axis and a short axis on the y axis, and the inclination of the edge on the yz plane. Although the case where the angle α is formed to be about 45 degrees and the center of the light emitting element is slightly shifted from the z axis to the lower side of the y axis has been described, the present invention is not limited to this. However, the concave reflecting surface may have a spheroidal shape or the like or another shape, and the concave reflecting surface of the light emitted by the light emitting element is irrespective of the position of the light emitting element. It is sufficient that the light reflected by the substantially lower half surface of the above is externally radiated substantially parallel to the z-axis, and the light reflected by the approximately upper half surface of the concave reflecting surface is externally radiated downward. For example, the concave reflecting surface is formed such that the upward curvature of the y axis is larger than the downward curvature of the y axis as shown in FIGS. 10 and 11, and the light emitting element is arranged on the z axis. The light reflected by the lower surface of the concave reflecting surface is radiated to the outside substantially parallel to the z-axis, and the light reflected on the upper surface of the concave reflecting surface is radiated downward in the light emitted by It can be anything.

Further, in the above-mentioned first to third embodiments, the case where one light emitting element is arranged has been described, but two or more light emitting elements may be used as shown in FIGS. 12 and 13, for example. Good.

In addition, in the above-described first to third embodiments, the case where nine light emitting diodes are arranged in each light emitting diode lamp has been described, but the number of light emitting diodes may be one, or 10 or more. Good.

〔The invention's effect〕

As described above, according to the present invention, by improving the radiation efficiency of light in a predetermined direction and reducing the amount of external light incident on the concave reflecting surface, the contrast at the time of lighting and at the time of extinguishing is improved. Thus, it is possible to provide a light emitting diode lamp that is easily visible even outdoors during the day.

[Brief description of drawings]

FIG. 1 is a schematic front view of a light emitting diode lamp which is a first embodiment of the present invention, FIG. 2 is a schematic structural sectional view when a plurality of the light emitting diode lamps are vertically arranged, and FIG. 3 is a light emitting diode thereof. Fig. 4 is a schematic front view of a light-emitting diode used in a lamp, Fig. 4 is a schematic structural sectional view of the light-emitting diode, and Fig. 5 shows the relationship between W / D and the incident angle φ of external light with respect to the light emission angle θ. FIG. 6 is a schematic front view of a light emitting diode lamp according to a second embodiment of the present invention, FIG. 7 is a schematic structural sectional view when a plurality of the light emitting diode lamps are vertically arranged, and FIG. FIG. 9 is a schematic front view of a light emitting diode lamp which is a third embodiment of the present invention, FIG. 9 is a schematic structural sectional view when a plurality of light emitting diode lamps are vertically arranged, and FIG. 10 is used in the embodiment of the present invention. Of the first modified example Schematic front view of a diode, 11
FIG. 12 is a schematic structural sectional view of a light emitting diode of a first modification thereof, FIG. 12 is a schematic front view of a light emitting diode of a second modification used in the embodiment of the present invention, and FIG.
14 is a schematic structural sectional view of a light emitting diode of a modification, FIG. 14 is a schematic front view of a conventional light emitting diode lamp, FIG. 15 is a schematic structural sectional view when a plurality of the light emitting diode lamps are vertically arranged, FIG. Is a schematic front view of a light emitting diode used in the light emitting diode lamp, and FIG. 17 is a schematic structural sectional view of the light emitting diode. 1 ... Light emitting diode, 2, 2a, 2b ... Eaves, 3 ... Holding case, 11 ... Light emitting element, 12, 13 ... Lead frame, 14 ... Wire, 15 ... Light transmissive material, 16 ...... Concave reflection surface, 17 ...... Radiation surface.

Claims (3)

(57) [Claims] 1. A light emitting diode comprising: a light emitting element; a lead portion for supplying electric power to the light emitting element; and a concave reflecting surface provided so as to face the light emitting surface of the light emitting element. In a light emitting diode lamp in which a canopy for preventing incidence on the concave reflecting surface is formed on the light emitting diode, the light emitting element emits a substantially lower half surface when the concave reflecting surface is viewed from the front. The light is reflected so as to be substantially parallel to the central axis of the concave reflecting surface, and the substantially upper half surface of the concave reflecting surface when viewed from the front reflects the light emitted by the light emitting element downward. A light emitting diode lamp characterized in that it is formed on. 2. The light emitting diode lamp according to claim 1, wherein a plurality of the light emitting diodes are arranged, and the eaves are provided corresponding to the respective light emitting diodes. 3. The light emitting diode lamp according to claim 2, wherein the eaves provided on the upper part of the eaves are formed to have a longer dimension than other eaves.