JP7223646B2 - Ring type light injection device - Google Patents

Description

The present invention relates to a ring-shaped light emitting device.

As a conventional ring-shaped light emitting device used in a work inspection system, as shown in Patent Document 1, a flexible wiring board on which a plurality of bullet-shaped LEDs are mounted is arranged so that each of the bullet-shaped LEDs is positioned on the inner surface side. A structure that is rounded to form a truncated cone is known.

In this type of ring-type light emitting device, a workpiece is arranged in the light emitting direction, and a camera is arranged on the opposite side of the light emitting direction. It is configured for imaging.

However, since the conventional ring-shaped light emitting device has a thick structure formed by rounding a flexible wiring board into a truncated cone shape, there is a limit to reducing the thickness of the device. Moreover, since bullet-shaped LEDs are used, a dramatic increase in the amount of light cannot be expected.

JP-A-2008-139708

Accordingly, it is an object of the present invention to provide a ring-shaped light emitting device which can be made thinner, can increase the amount of light, and is easy to manufacture, as compared with the conventional ring-shaped light emitting device. This is the main issue.

That is, the ring-shaped light emitting device according to the present invention includes a plane substrate having an observation hole, an LED chip array formed by arranging LED chips in a ring shape on the plane substrate so as to surround the observation hole, and the LED chip array. A first dam member annularly provided inside the LED chip row, a second dam member annularly provided outside the LED chip row, and a gap between the first dam member and the second dam member filled and a translucent member.

With such a device, the COB type structure in which the LED chips are mounted on the flat substrate is adopted, so that the device can be made thinner.

In addition, because of the COB type structure, the LED chips can be densely installed in the same area as compared with the case of using bullet-shaped LEDs. As a result, the amount of light emitted from the ring-shaped light emitting device can be increased, which can contribute to improvement in inspection accuracy and inspection speed.

Furthermore, by filling the space between the first dam member and the second dam member with the translucent member, a plurality of LED chips can be collectively sealed, which facilitates the manufacture thereof.

Further, as a specific configuration of the translucent member, the translucent member may be filled between the first member and the second member so as to rise in a convex shape. good.

With such a structure, the light emitted from each LED chip can be directed in a specific direction due to the lens effect of the light-transmitting member that rises in a convex shape.

Moreover, as a specific configuration of the first dam member and the second dam member, the height of the first dam member and the height of the first dam member may be different.

With such a configuration, it is possible to change the convex shape of the translucent member by adjusting the height of the first dam member and the height of the second dam member. Thereby, the direction of light emitted from each LED chip row can be freely changed.

Furthermore, as a specific arrangement of the LED chip row, the LED chip row may be arranged closer to the second dam member than the first dam member.

With such a configuration, when the light emitted from the LED chip row is irradiated toward the center, it is difficult to be blocked by the first dam member, and as a result, more light is emitted from the LED chip row. condensed.

Further, a third dam member annularly provided outside the second dam member is further provided, and a second LED chip row is further provided between the second dam member and the third dam member, A translucent member filled between the second dam member and the third dam member may be further provided.

With such a configuration, the number of LED chip rows increases, so the amount of light increases. In addition, for example, by switching the LED chip rows to emit light, it is possible to separately irradiate the work with the light emitted from each LED chip row. In this case, if each LED chip array is configured to have a different emission color or illuminance distribution, a single device can irradiate a work with a plurality of types of light.

According to the ring-shaped light emitting device configured in this way, it is possible to reduce the thickness and increase the amount of light. Also, it is easy to manufacture.

1 is a perspective view schematically showing a ring-shaped light emitting device according to an embodiment; FIG. It is a mimetic diagram showing a ring type light injection device concerning an embodiment. It is a graph which shows the relationship between the distance from the center of the ring-shaped light injection device which concerns on embodiment, and irradiance. It is a sectional view showing typically the ring type light emission device concerning other embodiments.

A ring-type light emitting device according to the present invention will be described below with reference to the drawings.

A ring-shaped light emitting device according to the present invention is used to irradiate a work to be inspected with light. For example, it is used when inspecting the contour shape and outer dimensions of a workpiece, and when inspecting a transparent workpiece for flaws, stains, and the like.

<Embodiment> As shown in FIGS. 1 and 2, a ring-type light emitting device 100 according to this embodiment includes a planar substrate 10, an LED chip 20, a first dam member 30, and a second dam member 40. , and a translucent member 50 . The ring-type light emitting device 100 has a COB type structure in which the LED chip 20 is directly mounted on the flat substrate 10 . 2(a) is a plan view of the ring-shaped light emitting device 100, and FIG. 2(b) is an enlarged cross-sectional view of the ring-shaped light emitting device 100 taken along line AA. (c) is an enlarged cross-sectional view of the ring-shaped light emitting device 100 cut along a part of the LED ring row 20r.

As shown in FIG. 2(a), the planar substrate 10 has an annular shape with an observation hole H in the center. Note that the flat substrate 10 is formed of a plate material made of metal such as aluminum having high heat dissipation, for example.

The LED chip 20 has, for example, a structure in which an n-type layer, a light-emitting layer and a p-type layer of a gallium nitride compound semiconductor are laminated in this order on a sapphire substrate, or a conductive substrate having a reflective layer laminated thereon. It has a structure in which gallium nitride compound semiconductors are laminated in order of a p-type layer, a light emitting layer and an n-type layer.

The LED chips 20 are arranged in an annular shape on the flat substrate 10 so as to surround the observation hole H to form an LED chip row 20r. Note that the LED chips 20 are arranged at equal intervals in the circumferential direction of the observation hole H. As shown in FIG. 2B and 2C, the LED chip 20 is placed on the planar substrate 10 with an insulating member X interposed therebetween. Specifically, the LED chip row 20r has adjacent LED chips 20s and 20e connected by wires Y to a wiring substrate Z placed on the flat substrate 10 with an insulating member X interposed therebetween. When one of the adjacent LED chips 20s and 20e is the start end and the other is the end end, the LED chips 20 forming the LED chip row 20r are connected in series by a wire Y from the start end to the end. It is As a material for forming the insulating member X, silicone-based resin, epoxy-based resin, or the like can be used.

The first dam member 30 is annularly provided along the inner edge of the planar substrate 10 inside the LED chip row 20r. Further, the second dam member 40 is annularly provided along the outer edge of the planar substrate 10 outside the LED chip row 20r. The first dam member 30 and the second dam member 40 are formed by piling up resin on the flat substrate 10 and have a convex cross section. A white silicone-based resin or the like can be used as the resin. By using a white resin, the light emitted from the LED chip row 20r can be easily reflected. Further, in the present embodiment, resin having a higher viscosity than the material of the translucent member 50 is used as the material of the first dam member 30 and the second dam member 40, but the material is not limited to this.

Both the first dam member 30 and the second dam member 40 are provided concentrically with the LED chip row 20r. Therefore, the first member 30 and the second member 40 form a double annular shape concentrically arranged.

Further, as shown in FIG. 2(b), the height of the second dam member 40 of the present embodiment is configured to be higher than that of the first dam member 30. As shown in FIG. Furthermore, the LED chip row 20r of the present embodiment is arranged closer to the second dam member 40 than the first dam member 30 is. That is, the LED chip row 20r is arranged outside the center between the first dam member 30 and the second dam member 40 in the inner-outer direction (radial direction).

The translucent member 50 is filled between the first dam member 30 and the second dam member 40 so as to rise in a convex shape. The peak 51 of the translucent member 50 is positioned closer to the first dam member 30 than the LED chip row 20r. That is, when viewed in cross section in the inner-outer direction (radial direction), the translucent member 50 has its apex positioned closer to the first dam member 30 than the LED chip row 20r. As a result, as shown in FIG. 3, an illuminance distribution is obtained in which the irradiance increases toward the center of the observation hole H and the irradiance becomes maximum at the center of the observation hole H. FIG. As the translucent member 50, translucent silicone-based resin, epoxy-based resin, or the like containing phosphor can be used.

In addition, the translucent member 50 has a surface formed between the first dam member 30 and the second dam member 40 by the resin filled between the first dam member 30 and the second dam member 40, for example. It is formed in a convex shape by swelling due to tension.

With such a configuration, since it has a COB type structure in which the LED chip 20 is directly mounted on the flat substrate 10, it can be made thinner. Furthermore, the LED chips 20 can be densely arranged, and the amount of light can be increased. In addition, since the structure is such that the translucent member 50 is filled between the first dam member 30 and the second dam member 40, the manufacturing thereof is facilitated. In addition, if a COB type structure in which the LED chip 20 is directly mounted on the flat substrate 10 is used, the absolute maximum rated current can be set higher than that of the conventional ring-type light emitting device, which can also be expected to increase the amount of light. .

<Other Embodiments> Modifications of the ring-type light emitting device 100 according to the above-described embodiments include those shown in FIGS. 4(a) to 4(d). Note that the insulating member X, the wire Y, and the wiring board Z are omitted in FIGS. 4(a) to 4(d).

In the ring-shaped light emitting device 100 shown in FIG. 4A, the LED chip row 20r is arranged closer to the second dam member 40 than the first dam member 30, and the height of the second dam member 40 is the first It is configured to be lower than the height of the dam member 30 . The peak 51 of the translucent member 50 is located closer to the first dam member 30 than the LED chip row 20r. Even with such a configuration, a large amount of light emitted from the LED chip row 20r can be collected.

4B further includes a third dam member 60 outside the second dam member 40, and a third dam member 60 between the second dam member 40 and the third dam member 60. A second LED chip row 70r is provided in which two LED chips 70 are arranged in a ring, and a second translucent member 80 filled between the second dam member 40 and the third dam member 60 is provided. With such a configuration, since the second LED chip row 70r is added to the ring-shaped light emitting device 100, the amount of light increases. In this embodiment, three dam members are provided, but three or more dam members may be provided.

In the case of having a plurality of LED chip arrays 20r and 70r in this way, the LED chip arrays 20r and 70r may be switched to be lit. In this case, if the LED chip rows 20r and 70r are configured to emit light having different wavelengths, illuminance distributions, and the like, different types of light can be emitted to the work by the LED chip rows 20r and 70r.

4(c), the LED chip row 20r is arranged at the center of the inside and outside direction between the first dam member 30 and the second dam member 40, and the first dam member 30 and the height of the second member 40 are configured to be the same height. The translucent member 50 is formed in a convex shape so that the ridge 51 is positioned on the center in the inward and outward direction between the first dam member 30 and the second dam member 40 . Even with such a configuration, the light emitted from the LED chip row 20r is condensed by the translucent member 50. FIG.

4D, the LED chip row 20r is arranged closer to the second dam member 40 than the first dam member 30, and the height of the first dam member 30 and the second The height of the member 40 is configured to be the same height. The translucent member 50 has a flat surface.

The translucent member 50 may be filled between the first dam member 30 and the second dam member 40 and formed to have a concave shape.

In this way, by appropriately adjusting the position of the LED chip row 20r between the first dam member 30 and the second dam member 40 and the shape of the translucent member, the amount of light emitted from the LED chip row 20r can be reduced. Illuminance distribution can be changed. In addition, the illuminance distribution of light is not limited to the mode in which the light is focused in the center of the observation hole H (inside the plane substrate 10), and the light is focused in front of the LED chip row 20r, or in the plane substrate 10. Light may be condensed on the outside.

In addition, in the above embodiment, the first dam member 30, the second dam member 40, and the LED chip row 20r are formed in an annular shape. Alternatively, as long as it is annular, it may be formed in other shapes (for example, a star shape, etc.).

Furthermore, in the above-described embodiment, one LED chip row 20r is provided between the first dam member 30 and the second dam member 40, but a plurality of rows may be provided. Even with such a device, the number of LED chip rows 20r constituting the ring-type light emitting device 100 increases, so the amount of light increases.

Further, in the above embodiment, a substrate made of metal is used as the flat substrate 10, but for example, a printed substrate, a ceramics substrate, or the like may be used. In this case, it is not necessary to provide the insulating member X between the flat substrate 10 and the LED chip 20 as in the above embodiment.

In addition, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications are possible without departing from the spirit of the present invention.

100 Ring-type light emitting device 10 Planar substrate H Observation hole 20 LED chip 20r LED chip row 30 First dam member 40 Second dam member 50 Translucent member 60 Third dam member 70 Second LED chip 80 Second translucent member

Claims (4)

a planar substrate having an observation hole;
an LED chip array formed by arranging LED chips in a ring on the planar substrate so as to surround the observation hole;
a first dam member annularly provided inside the LED chip row;
a second dam member annularly provided outside the LED chip row;
a translucent member filled between the first dam member and the second dam member ;
The translucent member is filled between the first dam member and the second dam member so as to bulge in a convex shape,
A ring-shaped light emitting device , wherein a convex vertex of the translucent member is located closer to the center of the observation hole than the LED chip row . 2. The ring-shaped light emitting device according to claim 1 , wherein the height of the first dam member and the height of the second dam member are different. 3. The ring-shaped light emitting device according to claim 1, wherein the LED chip row is arranged closer to the second dam member than to the first dam member. further comprising a third dam member annularly provided outside the second dam member;
A second LED chip row is further provided between the second dam member and the third dam member,
4. The ring-type light emitting device according to claim 1, further comprising a translucent member filled between said second dam member and said third dam member.

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