JPS61292801A - Lighting apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lighting device suitable for use in military lighting, etc., and particularly in a lighting device that uses a large number of light emitting diodes as a light source, a lighting device that is used diagonally forward from a semiconductor chip. The present invention relates to a lighting device that effectively utilizes light emitted from the outside to improve lighting effects.

[Conventional technology]

In recent years, with the development of semiconductor technology, high-brightness light-emitting diodes have been developed and are now available at low prices, so they are used instead of light bulbs as light sources for vehicle lights, brake lights, taillights, etc. I am glad that I have been able to consider doing so.
As an example, the one shown in FIG. 5 is known. The light body 4 is formed by a rear cover 1' whose front surface is open, and a front lens 2 which has a large number of diffuser lenses 3 densely formed on the inner surface and which closes the front opening of the back cover 1'. A board 6 on which a large number of light emitting diodes 5 are mounted in a matrix at predetermined intervals is disposed inside the lamp body 4, and when the light emitted from each light emitting diode 5 passes through the front lens 2, A diffusion lens 3 is used to provide diffusion.

[Problem that the invention seeks to solve]

By the way, in the case of a light emitting diode 5, especially one molded with a highly transparent resin 8 such as epoxy resin in order to shield and protect the semiconductor balance 7 from the outside air, the tip of the resin 8 itself is formed into a dome shape to improve the directionality of light. , the axial direction of the light emitting diode 5 is illuminated most brightly.
Therefore, even though the light is diffused by the diffusing lens 3, a difference in brightness occurs in the front lens 2, which poses a problem in terms of uniform illumination. Therefore, it is possible to increase the number of light emitting diodes 5, but in that case, it would be foolish to increase the cost, and if they are placed too close together, the amount of light emitted will decrease due to heat generation between the diodes, so it will not be as bright as expected. Another problem arises in that it cannot be obtained.

In addition, since the semiconductor chip 7 is usually placed near the focal position of the dome portion or shifted from the focal position toward the p-board 6 side in order to improve the directivity of the light, some of the light emitted from the semiconductor chip 7 is absorbed by the light emitting diode 50. The disadvantage is that the light emitted diagonally forward at a large angle with respect to the optical axis does not pass through the dome portion and is not effectively utilized for illuminating the front lens 2.

In addition, a light emitting diode in which the semiconductor chip 7 is simply mounted on the substrate 6 without being molded with the resin 8 constitutes a point light source, so it is brightest around the optical axis and becomes darker as it moves away from the optical axis, resulting in a uniform brightness. Lighting was difficult.

[Failure to solve the problem]

The lighting device according to the present invention has been made in view of the above-mentioned points, and the semiconductor chip of each light emitting diode is molded with transparent resin, and a spherical lens portion is provided on the front surface of the transparent resin to correspond to the semiconductor chip. A large number of fisheye condensing lenses are formed in front of the transparent resin and an inner lens formed in correspondence with each light emitting diode is disposed in front of the transparent resin, and a large number of diffusing lenses are formed on the inner surface. A shaped outer lens is disposed in front of the inner lens, and the semiconductor chip is positioned in front of the focal point position of the spherical lens portion.

[Effect]

In the present invention, since the semiconductor chip is placed in front of the focal point of the spherical lens part, the solid angle of the light that passes through the spherical lens part among the light emitted from the chip is large, and more Light can be used effectively and the area ahead can be brightly illuminated. Furthermore, since the fisheye condensing lens converts a point light source into a surface light source, it reduces the directivity of the light emission output and prevents the occurrence of brightness differences.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a sectional view of a main part showing an embodiment of the illumination device according to the present invention applied to a tail light of an automobile, and FIG. 2 is a perspective view of an inner lens. In these figures, taillight 10
The lamp body 1 includes a frame body 12 with open front and rear surfaces, an outer lens 13 that closes the front opening of the frame body 12, and a substrate 14 that closes the rear opening of the frame body 12.
1 is formed. Inside the lamp body 11, an inner lens 15, a large number of light emitting diodes 16 disposed on the inner surface of the substrate 14, a diode defining member 17, etc. are disposed.

The outer lens 13 is made of translucent resin or glass colored in a predetermined color, and on its inner surface, a diffusion lens 18 consisting of a large number of small convex lenses is densely formed.

The inner lens 15 is made of transparent or light-transmitting resin, and has a large number of fisheye condensing lenses 19 densely formed on its surface. The fisheye condensing lens 19 controls the light from the light emitting diode 16 that passes through the inner lens 15 to be refracted and becomes approximately a thousand line rays, and as shown in FIG. Consisting of hemispherical spherical lenses with approximately equal rectangular contours,
has been done.

Each of the light emitting diodes 16 is mounted on the substrate 14 in correspondence with each of the fisheye condensing lenses 19 of the inner lens 15.
2 , 23 , a gold wire 24 and the like, and a good conductor is formed in a substantially dish shape between one lead wire 22 and the semiconductor balance 21 to direct diagonally backward light out of the semiconductor balance 21. A reflecting plate 25 is interposed to reflect the light forward.

The semiconductor balance 21 and the external lead wire 23 are connected by a gold wire 24, and the pair of lead wires 22 and 23 are respectively connected to the electric circuit of the substrate 14.

The diode defining member 17 is integrally formed of opaque synthetic resin, and has a large number of diode accommodating portions 28 in which each of the light emitting diodes 16 is individually and independently defined. The diode storage portion 28 is the diode defining member 17
The inner wall surface has a reflective surface formed by vapor deposition of aluminum, coating with paint with excellent reflective properties, and pasting of aluminum foil. Further, each diode housing portion 28 is filled with a transparent resin 30, and the light emitting diode 16tl is molded therein.

Epoxy resin or the like is used as the resin 30, and the surface thereof forms a substantially hemispherical bulge to form a spherical lens portion 31. The semiconductor chimp 21 is located in front of the focal point P of the lens portion 31.

In the tail light 10 having such a configuration, the light directed forward out of the light emitted from the semiconductor depth 21 passes through the resin 30 and the inner lens 15 in order, and passes through the outer lens 13.
irradiate. At this time, the light is refracted toward the center of the lens portion 31 by the spherical lens portion 31 of the resin 3G, and further refracted by the fisheye condensing lens 19 of the inner lens 15, thereby becoming approximately parallel light rays. The light is directed forward, and the light is diffused by the diffusion lens 18 of the outer lens 13 to obtain a desired light distribution.

Here, if the semiconductor balance 21 is placed in front of the focal point P of the spherical lens part 31 as shown by the solid line in FIG. The solid angle θ of light passing through the lens portion 31 when the semiconductor chip is disposed at the P position can be set more sharply. Therefore, the spherical lens portion 3
Since the amount of light that passes through the outer lens 1 and goes forward increases, there is less loss of light and the outer lens 13 can be illuminated more brightly.

Further, even if the light emitting diode 16 itself is a point light source, when the light passes through the spherical lens section 31 and the fisheye condensing lens section 19, it is emitted from the entire surface and reaches the outer lens 13.
When looking at the taillight 10 from the front, the light emitted from the light emitting diode 16 shines in a planar shape, making it appear as if it were a planar light source.

As a result, the directivity of the light emission output is reduced and the difference in brightness is reduced, so that the entire surface of the outer lens 13 is illuminated with substantially uniform brightness.

Specifically, each light emitting diode 16 is connected to the diode defining member 1.
Since it is separated from other light emitting diodes by 7,
The diodes can be placed close to each other without degrading the light emitting performance due to mutual heat generation.

FIG. 4 is a sectional view of a main part showing another embodiment of the present invention.

This embodiment is constructed by mounting a large number of light emitting diodes 5'jfr on a substrate 14, in which a semiconductor chip 7 is molded with a transparent resin 8 as an envelope, similar to the conventional structure shown in FIG. The distal end surface of the transparent resin 8 is formed into a dome shape, thereby forming a spherical lens portion 40. However, the light emitting diode 5 of the conventional structure is different in that the semiconductor tip 7 is disposed in front of the focal point P of the lens portion 40. In addition, in this embodiment, the first
Although the diode defining member 17 shown in the illustrated embodiment is omitted, it goes without saying that it is desirable to use the diode defining member 17 when it is necessary to prevent the effects of heat generation between diodes.

Note that 42 is a diode lighting resistor.

Even in such a configuration, since the semiconductor chip 7 is placed in front of the focal point P position of the spherical lens portion 40,
It is clear that the same effects as in the above embodiment can be obtained.

〔Effect of the invention〕

As explained above, in the lighting device according to the present invention, a spherical lens part is integrally formed on the front surface of a transparent resin in which a light emitting diode is molded, and the semiconductor balance of the diode is arranged in front of the focal point of this lens part. With this structure, the solid angle of light passing through the spherical lens portion can be increased, or in other words, the amount of light passing through the lens portion can be increased. Therefore, light loss is reduced and the lighting effect can be improved. In addition, an inner lens formed of a large number of fisheye condensing lenses corresponding to each diode is disposed between the outer lens and the light emitting diode,
Since the light emitting diode is substantially converted from a surface light source to a surface light source by the fisheye condensing lens, the entire surface of the outer lens can be illuminated with substantially uniform brightness.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention applied to a tail light of an automobile, FIG. 2 is a perspective view of an inner lens, and FIG. 3 is a diagram for explaining the present invention in detail. FIG. 4 is a sectional view of a main part showing another embodiment of the present invention, and FIG. 5 is a sectional view of a main part showing a conventional example of a lighting device. 1... Bank cover, 5... Light emitting diode,
6...Substrate, 7...Semiconductor chip, 8...
Transparent resin, 11...) Lamp body, 13... Outer lens, 14... Substrate, 15... Inner lens, 16... Light emitting diode, 17... Diode picture component, 18...diffusion lens, 19...
Fisheye condensing lens, 30...Transparent resin, 31...
Spherical lens part.

Claims (1)

[Claims] In a lighting device using a large number of light emitting diodes as a light source, the semiconductor chips of each light emitting diode are molded with a transparent resin, and a spherical lens portion is integrally formed on the front surface of the transparent resin in correspondence with the semiconductor chip. In front of the transparent resin, an inner lens is disposed in which a large number of fisheye condensing lenses are formed corresponding to each light emitting diode, and further in front of the inner lens, a large number of diffusing lenses are formed on the inner surface. 1. An illumination device comprising: an outer lens having a spherical shape, the semiconductor chip being disposed in front of a focal point of the spherical lens portion.