JPH1131848A - Light-emitting diode lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting diode lamp wherein, using a plurality of reflective light-emitting diodes as a light source, with good workability, comprising optical characteristics such as uniformity ratios in illuminance is high in an irradiated area, while irradiation density is high. SOLUTION: The lamp comprises a plurality of light-emitting diodes 10 and holders for holding them, and each of the light-emitting diodes 10 comprises a light-emitting element 12, lead parts 14a-d for supplying power to the light- emission element 12, a concave reflective surface 22 provided while facing the light-emitting surface of each light-emitting element 12, a radiant surface 24 for radiating the light reflected on the concave reflective surface 22 outside, and a supporting part 26 provided around the radiant surface 24. The holders are arranged such that each light-emitting diode 10 is direction at the same irradiated point, while the distance between the irradiated point and each light- emitting diode 10 becomes equal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a light-emitting diode lamp using a plurality of reflective light-emitting diodes which emit light emitted from a light-emitting element after being reflected by a concave reflecting surface and radiating the light to the outside.

[0002]

2. Description of the Related Art In general, there is a halogen bulb as a light source used for a printer, a copier, a facsimile or the like as an optical apparatus. Recently, attention has been paid to light-emitting diodes from the viewpoint of the problem of heat rays from a light source in an optical device, the size and volume of the device, the ease of controlling the light source, or the life of the light source. As this type of light emitting diode, a lens type light emitting diode in which a light emitting element is molded in a light transmitting resin formed in a lens shape as shown in FIG. 5 is known. In FIG. 5, reference numeral 50 denotes a lens-type light emitting diode, 52 denotes a light emitting element, and 54a and 54b.
Is a lead, 56 is a wire, 58 is a light-transmitting resin, and 59 is a lens surface that emits light. Further, a reflection type in which a light emitting element is molded in a light transmissive resin, and a reflection surface is formed on the resin on the side facing the light emitting surface of the light emitting element, and a radiation surface is formed on the back side, as previously proposed by the present applicant. Light emitting diodes are also well known.

In a structure such as an image recognition light source or a large-diameter optical fiber light source, which irradiates light to an area having a diameter of several centimeters, a plurality of lens-type light emitting diodes are arranged in a predetermined direction on the same substrate. A dense array of lamps is used for this purpose. FIGS. 6 and 7 show this light emitting diode lamp 60, which has a substantially circular lamp body 6.
A plurality of lens-type light-emitting diodes 50 are arranged on the same circumference, and leads 54a and 54b of each light-emitting diode 50 are mounted on a mounting board 64, and a lens surface 59 is directed to an external irradiation direction. In FIG. 7, the leads 54a and 54b have a positional relationship in which the leads 54a and 54b can be seen to overlap so as to direct the lens-type light emitting diode in a predetermined direction. In this light-emitting diode lamp, the light emitted from each light-emitting diode is applied to the irradiation area because each light-emitting diode is oriented in the same direction. However, such a light emitting diode lamp has a problem that irradiation characteristics with high uniformity cannot be obtained or it is very difficult.

[0004]

In a halogen bulb, light is radiated from one place and is condensed at one point. Therefore, the optical distance from the light source to the converging point is determined by the light radiated from any position on the reflecting surface. Is also equal. On the other hand, in the light emitting diode lamp, since the output of each photodiode alone is small, a large number of light emitting diodes are arranged and light is emitted from a plurality of positions. Since the plurality of light emitting diodes are arranged on the same plane, the distance to the irradiation area differs depending on the position where the light emitting diodes are arranged.

[0005] By the way, even if the optical system is configured to extract parallel light, the light emitted from the light emitting diode is spread due to the size of the light emitting element itself as a light source. The spread of the irradiation distribution of the diode depends on the irradiation distance. Therefore, in a light-emitting diode lamp in which a plurality of lens-type light-emitting diodes are arranged on the same plane, the distribution of light that each light-emitting diode irradiates the irradiation area is different. In particular, there is a difference in the irradiation density between the central part of the irradiation area irradiated from all the light emitting diodes and the peripheral part of the irradiation area where irradiation can be obtained only from the light emitting diode with a long irradiation distance, and the irradiation distribution with low uniformity Become.

[0006] Since irradiation distribution with a high degree of uniformity cannot be obtained simply by simply arranging the light emitting diodes, if a high degree of uniformity is required, the direction of each light emitting diode is adjusted while measuring the irradiation distribution. Therefore, there is a problem that work for obtaining desired characteristics is required, and workability is extremely poor. Further, in the lens type light emitting diode, when the directivity is increased, the control efficiency of light emitted from the light emitting element is significantly reduced, so that there is a problem that the irradiation efficiency to the irradiation area is reduced.

The present invention has been made in view of the above, and has a light emitting diode lamp which uses a plurality of reflective light emitting diodes as a light source, has good workability, has a high degree of uniformity in an irradiation area, and has high optical density. The purpose is to provide.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a plurality of light emitting diodes and a holder for holding the plurality of light emitting diodes, each of the light emitting diodes supplying a light emitting element and a power supply to each light emitting element. A light emitting surface of each light emitting element, a concave reflecting surface provided to face the light emitting surface of each light emitting element, a radiation surface for radiating light reflected by the concave reflecting surface to the outside, and a peripheral portion of the radiation surface. The holder is arranged so that each light emitting diode is directed to the same irradiation point, and the distance between the irradiation point and each light emitting diode is equal. . Further, the holder has a fitting portion which is inserted from the radiation surface side of the light emitting diode and fits the support portion, and a contact surface which is in contact with an upper end surface of the support portion formed in the fitting portion. And the contact surface is formed as a spherical surface with the irradiation point as the origin. Further, the concave reflecting surface of the light emitting diode has a paraboloid of revolution or a shape similar to the paraboloid of revolution focusing on the light emitting element, and the light emitting diode is perpendicular to a plane including an edge of the concave reflecting surface. The end of the reflection surface is cut symmetrically in a right and left plane, and the light emitting diodes are arranged in a ring.

[0009] According to the above configuration, a plurality of light emitting diodes can be arranged on a holder having a contact surface formed in a spherical shape with the irradiation point as the origin, and the distance between each light emitting diode and the irradiation area becomes the same. The distribution of light emitted from each light emitting diode to the irradiation area is substantially the same, and an irradiation distribution with a high degree of uniformity can be obtained. Further, a holder having a fitting portion inserted from the radiation surface side of the light emitting diode to fit the support portion, and a contact surface provided on the fitting portion and in contact with an upper end surface of the light emitting diode support portion. By using, the fitting portion can be used as a reference surface for positioning the light emitting diode, and the contact surface can be used as a reference surface for adjusting the orientation of the light emitting diode. Just by inserting and fitting, the position and orientation of each light emitting diode can be accurately and easily adjusted. Further, the concave reflecting surface of each light emitting diode has a paraboloid of revolution centered on a focal position where the light emitting element is disposed or a position in the vicinity thereof or a shape similar thereto, so that the light emitting element can be efficiently produced. , And high-density light can be emitted to the irradiated surface. Furthermore, since the end of the concave reflecting surface of each light emitting diode is cut, the light emitting diodes can be arranged densely in a ring on the holder, so that light with a high irradiation density is emitted to the irradiation area. be able to.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiment. FIG. 1 is a schematic front view of a light-emitting diode lamp according to an embodiment of the present invention, FIG. 2 is a schematic cross-sectional view in the direction of arrows AA of the lamp, and FIG. Schematic front view, FIG. 3 (b)
FIG. 3C is a schematic side view when the light emitting diode is viewed from the x-axis direction, FIG. 3C is a schematic side view when the light emitting diode is viewed from the y-axis direction, and FIG. FIG. 4B is a schematic cross-sectional view of the holder as viewed in the direction of arrows BB. In FIG. 3, the z axis is the direction of the central axis of the concave reflecting surface, and the x axis and the y axis are orthogonal coordinate axes on a plane including the light emitting surface of the light emitting diode. The light emitting diode lamp shown in FIGS.
It comprises two reflective light emitting diodes 10 and a holder 30. In the present embodiment, a case will be described in which a light source in which a plurality of light emitting diodes 10 are arranged in a ring is obtained.

As shown in FIG. 3, the reflection type light emitting diode 10 comprises a light emitting element 12 and leads 14a, 14b, 14
c, 14 d, the wire 16, the light-transmitting material 18, the concave reflection surface 22, the radiation surface 24, and the support portion 26. Here, the leads 14a and 14b are for supplying power to the light emitting element. The light emitting element 12 is the lead 1
The light emitting element 12 and the lead 14b are mounted on the light emitting element 4a and are electrically connected to each other by a wire 16. Further, the light emitting element 12, the distal ends of the leads 14a, 14b, 14c, 14d and the wire 16 are integrally molded with a light transmissive material 18. Then, the leads 14a, 14
The lead b and the leads 14c and 14d are pulled out from the side surface of the light transmitting material 18 in opposite directions. Note that the leads 14c and 14d are not for electric wiring, but for holding the light emitting diode as necessary.

The concave reflecting surface 22 is formed by mirror-finishing one surface of the light transmissive material 18 by plating, metal vapor deposition, or the like, and is formed on the side facing the light emitting surface of the light emitting element 12. Here, the concave reflecting surface 22 is formed in a shape close to a paraboloid of revolution corresponding to the light emitting pattern of the light emitting element 12, and the center of the light emitting surface of the light emitting element 12 is arranged at the focal point. On the other hand, the radiation surface 24 is formed on the back side of the light emitting element 12. Here, the radiation surface 24 is replaced by the concave reflection surface 22.
Are formed in a plane shape perpendicular to the central axis (z axis) of the light emitting element 12, and the emitting surface 24 and the light emitting surface of the light emitting element 12 are substantially parallel to each other. In the light emitting diode 10, the light emitted from the light emitting element 12 can be efficiently extracted as light parallel to the central axis of the concave reflecting surface 22, and can be used effectively.

In the light emitting diode 10, the end of the concave reflecting surface 22 is cut symmetrically on a plane perpendicular to the x-axis. Thereby, when the light emitting diodes 10 are arranged in a ring shape so that the cut surfaces of the concave reflecting surface 22 are adjacent to each other,
The distance between the light emitting diodes 10 can be reduced. By arranging the light emitting diodes densely in this manner, the irradiation density can be improved. That is, the loss due to the cutting off of the end of the concave reflection surface 22 is less than 10%, the efficiency of the dense arrangement is greater, and the irradiation density can be improved.

The supporting portion 26 serves to support the light emitting diode 10 when the light emitting diode 10 is mounted on the holder 30, and is formed around the radiation surface 24. In the present embodiment, since the end of the concave reflecting surface 22 is cut symmetrically in the left and right direction, the supporting portion 26 is formed as shown in FIG.
As shown in FIG. 3A, the upper and lower radiating surfaces 24 are formed. The upper end surface 26a of the support portion 26 is formed in a flat shape. In order to arrange the light emitting diodes 10 densely, the light emitting diodes 10 are finally trimmed and form cut, and the leads 14a, 14b, 14c, and 14d are bent toward the rear surface (toward the reflection surface 22) and connected.

To manufacture the light emitting diode 10, a transfer molding method is used. In the transfer mold method, the lower mold is used on the side where the shape is particularly important. However, in the light emitting diode 10, since the concave reflecting surface 22 controls the light from the light emitting element 12, the concave reflecting surface 22 is used. Is a lower mold and the radiating surface 24 is an upper mold. When this transfer molding method is used, not only can the concave reflection surface 22, the radiation surface 24, and the support portion 26 be molded with high precision, but also the leads 14a, 14b, 14
The positioning of c, 14d with the concave reflecting surface 22 and the radiating surface 24 can be accurately performed.

In the light emitting diode 10 having the above configuration, when power is supplied to the light emitting element 12, the light emitting element 12 emits light,
The light emitted from the light emitting element 12 is reflected by the concave reflecting surface 22 and is radiated outside from the radiation surface 24. By emitting the light emitted from the light emitting element 12 to the outside after being reflected by the concave reflecting surface 22 once, the light emitted from the light emitting element 12 can be effectively emitted forward.

The holder 30 is for holding a plurality of light emitting diodes at predetermined positions in a predetermined direction. The holding part 30 is formed with a fitting part 32 which is a through hole. The fitting portion 32 connects the light emitting diode 10 to the radiation surface 2.
4 and inserted. The light-emitting diode 10 has a contact surface 35 with which the upper end surface 26 a of the support portion 26 contacts, and an opening 37 into which the radiation surface 24 of the light-emitting diode 10 is inserted. Note that the contact surface 35 is formed as a spherical surface having the irradiation point as the origin.

[0018] Using such a light emitting diode 10, a light emitting diode
To form an iodide lamp, multiple light emitting diodes
10 is inserted into the holder 30 from the radiation surface 24 side,
The part 26 is fitted into the fitting part 32 and the support part 26 is
The upper end surface 26a is brought into contact with the contact surface 35 via an adhesive.
As a result, the light emitting diode 10 is attached to the holder 30.
I can. Thus, the plurality of light emitting diodes 10 have a concave shape.
The cut surfaces of the reflection surface 22 are arranged in an annular shape such that they are adjacent to each other,
A light emitting diode lamp as shown in FIGS.
You.

In the light emitting diode lamp of this embodiment,
Since the fitting portion of the holder is formed as a spherical surface with the irradiation point as the origin, the distance between each light emitting diode and the irradiation area is the same. For this reason, the distribution of light emitted from the light emitting diodes to the irradiation area is substantially the same, the light emitting diodes are arranged regularly, and an irradiation distribution with a high degree of uniformity can be obtained. Also, since the contact surface can be used as a reference surface for facing the light emitting diodes, the position and orientation of each light emitting diode can be accurately and easily determined simply by fitting the light emitting diode into the fitting portion of the holder. Can be aligned. Therefore, the emission surfaces of the light emitting diodes can be arranged in the same direction, and the central axes of the light emitting elements of the light emitting diodes can be aligned with high accuracy. When such a light-emitting diode array is used as a lamp for irradiating a predetermined range, it is possible to emit light with a high irradiation density with less irradiation unevenness on a surface to be irradiated.

The present invention is not limited to the above embodiment, and various changes can be made within the scope of the invention. In the above embodiment, the case where the ends of the concave reflecting surface are cut symmetrically and the light emitting diodes are arranged in a ring so that the cut surfaces of the concave reflecting surface are adjacent to each other, but the light emitting diodes are densely arranged. If not necessary, the end of the concave reflecting surface need not be cut. In the above embodiment, light emitting diodes of red, green, and blue emission colors may be combined. Thereby, white irradiation becomes possible.

[0021]

As described above, according to the present invention, the irradiation distribution of each light emitting diode can be made substantially the same by making the distance from each light emitting diode to the irradiation area equal. Therefore, a high degree of uniformity can be obtained only by regularly arranging the light emitting diodes, and by using the holder, the workability is good, and the position and the direction can be accurately and easily adjusted, and the high degree of uniformity is obtained. There is an advantage that a light emitting diode lamp can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a light emitting diode lamp according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view in the direction of arrows AA in FIG.

FIG. 3A is a schematic front view of a light emitting diode used in the light emitting diode lamp, FIG. 3B is a schematic sectional view of the light emitting diode viewed from the x-axis direction, and FIG. (c) is a schematic cross-sectional view of the light emitting diode when viewed from the y-axis direction.

FIG. 4A is a schematic front view of a holder used in the light-emitting diode lamp, and FIG.
FIG. 4 is a schematic cross-sectional view in the direction of arrow B.

FIG. 5 is a schematic front view of a conventional light emitting diode.

FIG. 6 is a schematic front view of a conventional light emitting diode lamp.

7 is a schematic cross-sectional view in the direction of arrows CC in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Light emitting diode 12 Light emitting element 14a, 14b, 14c, 14d Lead 16 Wire 18 Light transmitting material 22 Concave reflective surface 24 Radiation surface 26 Support 26a Top end surface 30 Holder 32 Fitting portion 35 Contact surface 37 Opening

Claims (5)

[Claims] A plurality of light-emitting diodes; and a holder for holding the plurality of light-emitting diodes, wherein each of the light-emitting diodes has a light-emitting element; A concave reflecting surface provided to face the light emitting surface of each light emitting element, a radiating surface for radiating light reflected by the concave reflecting surface to the outside, and a supporting portion provided around the radiating surface. And wherein the holder is arranged such that each light emitting diode is directed to the same irradiation point, and the distance between the irradiation point and each light emitting diode is equal. 2. The holding device according to claim 1, wherein said holding member is inserted from a radiation surface side of said light-emitting diode and fitted with a supporting portion, and a contact portion abutting on an upper end surface of said supporting portion formed in said fitting portion. The light-emitting diode lamp according to claim 1, wherein the light-emitting diode lamp has a surface, and the contact surface is formed as a spherical surface having an irradiation point as an origin. 3. The light-emitting diode lamp according to claim 1, wherein the concave reflecting surface of the light-emitting diode has a paraboloid of revolution whose shape focuses on the light-emitting element or a shape similar thereto. . 4. The light-emitting diode according to claim 1, wherein an end of said reflecting surface is cut symmetrically on a plane perpendicular to a plane including an edge of said concave reflecting surface. 3. The light emitting diode lamp according to 3. 5. The light emitting diode lamp according to claim 1, wherein said light emitting diodes are arranged in a ring.