JP2012009282A - Light-emitting device, and lighting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device and a lighting apparatus, capable of changing light-emitting colors with a simple constitution, and superior in balance of irradiated light as a whole.SOLUTION: The light-emitting device 1 includes: a first light source A which is equipped with a substrate 2, a first feeding line 21a and a second feeding line 21b formed on this substrate 2, a plurality of light-emitting elements 3 which are connected to the first feeding line 21a and mounted on the substrate 2, and a sealing member 4 to cover these plurality of light-emitting elements 3, and emits light of a prescribed correlated color temperature; and a second light source B which includes the plurality of light-emitting elements 3 connected to the second feeding line 21b and mounted on the substrate 2, and the sealing member 4 to cover this plurality of light-emitting elements 3, and emits light of the correlated color temperature different from the correlated color temperature of the first light source A. The first light source A and the second light source B are dispersedly deployed on the substrate 2.

Description

  Embodiments described herein relate generally to a light-emitting device and a lighting device that use light-emitting elements such as LEDs.

  Recently, a lighting device has been developed in which a plurality of light emitting elements such as LEDs are arranged on a substrate as a light source to obtain a predetermined amount of light. This lighting device is used, for example, as a so-called direct mounting type base lighting that is directly attached to a ceiling surface or the like. A large number of LED bare chips are mounted on a substrate, and each LED chip is bonded to a bonding wire. Are electrically connected and sealed with a sealing member containing a phosphor. Then, it tries to obtain light of daylight color, white color, light bulb color, and the like.

  By the way, in the said illuminating device, a desired luminescent color may be desired by illumination environment and liking. In this case, a method is considered in which a plurality of LEDs having different emission colors such as red, green, and blue are arranged on the substrate, and the emission intensity of each LED is adjusted and mixed to obtain a desired emission color.

JP 2008-522712 A

  However, in the above case, the configuration is complicated and a plurality of emission colors are mixed, so that there is a problem that it is difficult to obtain a desired emission color.

  The present invention has been made in view of such problems, and provides a light-emitting device and an illumination device that can change the emission color with a simple configuration and that has a good uniformity of irradiation light as a whole. Objective.

  The light-emitting device of the present invention includes a substrate and a first power supply line and a second power supply line formed on the substrate. The first light source includes a plurality of light emitting elements mounted on the substrate and a sealing member that covers the plurality of light emitting elements, and is connected to the first power supply line so as to have a predetermined correlation color. Emits temperature light. The second light source includes a plurality of light emitting elements mounted on the substrate and a sealing member that covers the plurality of light emitting elements. The second light source is connected to the second power feeding line, and Light having a correlated color temperature different from the correlated color temperature of the light source is emitted. The first light source and the second light source are arranged in a distributed manner on the substrate.

  According to the present invention, it is possible to provide a light-emitting device and a lighting device that can change the emission color and have good uniformity of the irradiation light as a whole.

It is a top view which shows the light-emitting device which concerns on the 1st Embodiment of this invention. It is typical sectional drawing which follows the YY line in FIG. It is a connection diagram which shows the connection state of the light emitting element. It is a perspective view which shows the illuminating device of the ceiling direct attachment type which has arrange | positioned the light-emitting device. It is a connection diagram which shows the connection state of the light emitting element in the light-emitting device which concerns on the 2nd Embodiment of this invention. It is a top view which shows the light-emitting device which concerns on the 3rd Embodiment of this invention.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3 show the light emitting device 1, and FIG. 4 shows an illumination device 11 using the light emitting device 1. In addition, the same code | symbol is attached | subjected to the same part in each figure, and the overlapping description is abbreviate | omitted.
As shown in FIG. 1, the light emitting device 1 includes a substrate 2, a plurality of light emitting elements 3, and a phosphor layer 4 as a sealing member that covers each light emitting element 3.

  The board | substrate 2 is formed in the elongate substantially rectangular shape with materials, such as a glass epoxy resin. The length dimension L of the substrate 2 is 250 mm to 300 mm, and the width dimension W is 30 mm to 40 mm. In the present embodiment, specifically, the length dimension L is 280 mm, and the width dimension W is 32 mm. The thickness dimension of the substrate 2 is preferably 0.5 mm or more and 1.8 mm or less, and in this embodiment, a thickness of 1 mm is applied.

  As for the shape of the substrate 2, for example, both ends in the longitudinal direction may be formed in an R shape. Moreover, a ceramic material or another synthetic resin material can be applied to the material of the substrate 2. Furthermore, the present invention is a metal base in which an insulating layer is laminated on one surface of a base plate having good thermal conductivity such as aluminum and excellent heat dissipation in order to enhance the heat dissipation of each light emitting element 3. It does not prevent the application of the substrate.

  As shown in FIGS. 1 and 2, a first power supply line 21 a and a second power supply line 21 b and a mounting pad 22 (not shown in FIG. 1) are formed on the substrate 2. Yes. The first power supply line 21a and the second power supply line 21b are wiring patterns, and each form an electrical power supply path independently.

  The positive electrode side line of the first power supply line 21a is formed linearly on the edge in the longitudinal direction of the substrate 2 (upper side in the drawing), and the negative electrode side line is formed so as to protrude in a comb shape. . On the other hand, the positive electrode side line of the second power supply line 21b is similarly formed linearly at the edge in the longitudinal direction of the substrate 2 (on the lower side in the drawing), and a plurality of negative electrode side lines protrude in a comb shape. The first feed line 21a is disposed so as to enter between adjacent protruding portions of the comb-like shape.

  That is, the portion of the first power supply line 21a that protrudes in a comb shape and the portion of the second power supply line 21a that protrudes in a comb shape enter between the adjacent protruding portions of the comb shape. It is arranged.

  A power supply terminal 21c is connected to the first power supply line 21a and the second power supply line 21b. The power supply terminal 21c is disposed on one end side of the substrate 2 and is connected to a power connector.

  As shown in FIG. 2, the first power supply line 21 a, the second power supply line 21 b, and the mounting pad 22 have a three-layer configuration. On the surface of the substrate 2, copper (Cu) as the first layer A, second Nickel (Ni) is electroplated as the layer B, and silver (Ag) having high reflectivity is electroplated in the third layer C. The third layer C of the mounting pad 22, that is, the surface layer is plated with silver (Ag) to form a reflective layer, and the total light reflectance is as high as 90%.

In this electrolytic plating process, it is preferable that the nickel (Ni) film thickness of the second layer B is 5 μm or more, and the silver (Ag) film thickness of the third layer C is 1 μm or more. By setting the film thickness, a uniform film thickness can be formed and the reflectance can be made uniform.
In addition, a white resist layer 23 having a high reflectance is laminated on the entire surface of the substrate 2 except for the mounting region of the light emitting element 3 and the component mounting portion.

  As shown in FIG.1 and FIG.2, the some light emitting element 3 consists of a bare chip of LED. For example, an LED bare chip that emits blue light in order to cause white light to be emitted from the light emitting unit is used. The bare chip of this LED is bonded onto the mounting pad 22 using a silicone resin insulating adhesive.

  An LED bare chip is, for example, an InGaN-based element, in which a light-emitting layer is stacked on a light-transmitting sapphire element substrate, and the light-emitting layer includes an n-type nitride semiconductor layer, an InGaN light-emitting layer, and a p-type nitride layer. A physical semiconductor layer is sequentially stacked. And the electrode for sending an electric current through a light emitting layer was formed with the p-type electrode pad on the p-type nitride semiconductor layer, and the n-type electrode pad on the n-type nitride semiconductor layer. It consists of a negative electrode. These electrodes are electrically connected by a bonding wire 31. The bonding wires 31 are made of gold (Au) fine wires, and are connected via bumps mainly composed of gold (Au) in order to improve mounting strength and reduce damage to bare LED chips.

  The plurality of light emitting elements 3 are mounted on the mounting pad 22 of the substrate 2 in a plurality of rows arranged in a direction perpendicular to the longitudinal direction of the substrate 2. Specifically, the six light emitting elements 3 are arranged at substantially equal intervals across the positive electrode side line and the negative electrode side line of the first power supply line 21a. In addition, the six light emitting elements 3 are arranged at substantially equal intervals between the positive electrode side line and the negative electrode side line of the second power supply line 21b.

  That is, a plurality of rows of light emitting elements 3 (9 rows) connected to the first power supply line 21a and a plurality of rows of light emitting elements 3 connected to the second power supply lines 21b (9 rows) are alternately arranged. A total of 18 light emitting element rows are formed in a distributed manner in a direction perpendicular to the longitudinal direction of the substrate 2.

  Further, in each light emitting element row, the electrodes of different polarities of the light emitting elements 3 adjacent to each other in the extending direction, that is, the plus side electrode of one of the light emitting elements 3 adjacent to each other, Among the adjacent light emitting elements 3, the minus side electrode of the other light emitting element 3 is sequentially connected by a bonding wire 31. Thus, the plurality of light emitting elements 3 constituting each light emitting element array are electrically connected in series. Therefore, the plurality of light emitting elements 3 emit light all at once in an energized state.

  Furthermore, in each light emitting element row, the electrode of one light emitting element 3 arranged at the end of the row is connected to the first power feeding line 21 a or the second power feeding line 21 b by a bonding wire 31.

  The light emitting elements 3 connected as described above are connected as shown in FIG. FIG. 3 shows the arrangement of the first power supply line 21 a, the second power supply line 21 b, and the light emitting elements 3 on the substrate 2.

  Nine series circuits each having six light emitting elements 3 connected in series are connected in parallel to the first power supply line 21a. Similarly, nine series circuits in which six light emitting elements 3 are connected in series are connected in parallel to the second power supply line 21b. The first power supply line 21a and the second power supply line 21b form an independent electric power supply path, and the first power supply line is provided by a changeover switch or the like provided on the power supply circuit side (not shown). 21a and the second power supply line 21b can be selectively switched.

  Each of the light emitting element rows is electrically provided in parallel with the first power supply line 21a and the second power supply line 21b, respectively, so that power is supplied through the first power supply line 21a and the second power supply line 21b. It has become. Therefore, even if any one of the light emitting element rows cannot emit light due to bonding failure or the like, light emission of the entire light emitting device 1 does not stop.

  Further, as shown in FIG. 1, a pair of mounting holes 5 for mounting the substrate is formed between the adjacent light emitting element rows near the both ends of the substrate 2. The attachment hole 5 is used when the light emitting device 1 is attached to the main body of the lighting device. Specifically, the mounting screw 51 as a fixing means passes through the mounting hole 5 and is screwed into the main body or the like of the lighting device to mount the light emitting device 1.

  Usually, the mounting holes 5 are provided at both end portions of the substrate 2, so that it is necessary to secure the space, and the substrate 2 is enlarged accordingly. However, according to the above configuration, it is possible to avoid an increase in size. In this case, when the fixing means is made of metal, an insulation distance can be secured. Furthermore, since the fixing means fixes not the both ends of the substrate 2 but the inner side in the longitudinal direction, that is, the intermediate portion of the substrate 2, deformation such as warpage of the substrate 2 can be effectively suppressed. In addition, as the fixing means, an insulating member such as a synthetic resin may be used.

  As shown in FIGS. 1 and 2, the phosphor layer 4 is made of a translucent synthetic resin, for example, a transparent silicone resin. In the present embodiment, the phosphor layer 4Y contains a yellow phosphor as a phosphor. Two types of phosphor layers, 4R, in which red phosphors are mixed with yellow phosphors at a predetermined mixing ratio, are applied.

  The phosphor layer 4Y covers the plurality of light emitting elements 3 connected to the first power supply line 21a, and the phosphor layer 4R covers the plurality of light emitting elements 3 connected to the second power supply line 21b. is doing. Therefore, the plurality of light emitting elements 3 connected to the first power supply line 21a and the phosphor layer 4Y constitute the first light source A, and the plurality of light emitting elements 3 connected to the second power supply line 21b and the fluorescent light. The body layer 4R constitutes the second light source B.

The phosphor layer 4 is composed of a set of a plurality of convex phosphor layers 4 a that cover each light emitting element 3 for each light emitting element 3. The convex phosphor layer 4a has a chevron shape, has an arcuate convex shape, and is formed so as to be continuous with the adjacent convex phosphor layer 4a at the skirt. Therefore, the phosphor layer 4 forms a plurality of rows along the light emitting element rows, that is, is formed in 18 rows, and covers and seals each light emitting device 3 and the bonding wire 31.
As described above, the first light source A and the second light source B are alternately and dispersedly formed in a plurality of rows in a direction orthogonal to the longitudinal direction of the substrate 2.

  The phosphor layer 4 is applied in an uncured state corresponding to each light emitting element 3 and the bonding wire 31, and is then cured by heating or standing for a predetermined time. Specifically, a transparent silicone resin material containing a phosphor whose viscosity and amount are adjusted is dropped from a dispenser (not shown) corresponding to each light emitting element 3 and bonding wire 31 in an uncured state.

  In the above configuration, the case where each light emitting element 3 is covered with each light emitting element 3 by the convex phosphor layer 4a has been described. For example, two or three of the plurality of light emitting elements 3 are arranged in the plurality of light emitting elements 3. You may form so that every light emitting element 3 may coat | cover.

  As shown in FIG. 2, the pattern of the heat radiating copper foil 6 is formed on the entire back surface of the substrate 2. With such a configuration, it is possible to equalize the temperature of the entire substrate 2 and improve the heat dissipation performance. Note that a resist layer is laminated on the copper foil 6.

  Next, the illuminating device 11 provided with the above-described light emitting device 1 will be described with reference to FIG. In the figure, a ceiling direct-mounted type lighting device 11 having a size equivalent to a general 40 W fluorescent lamp type lighting device installed and used on a ceiling surface is shown. The illuminating device 11 includes an elongated and substantially rectangular parallelepiped main body case 11a. In the main body case 11a, four light emitting devices 1 are linearly connected. Moreover, the power supply unit provided with the power supply circuit is built in the main body case 11a. A diffusible front cover 11b is attached to the lower opening of the main body case 11a.

  First, the first power supply line 21a in the light emitting device 1 having the above configuration is selected and energized by a changeover switch or the like on the power circuit side. The first light source A connected to the first power supply line 21a, that is, the light emitting elements 3 connected to the first power supply line 21a are turned on all at once, and the light emitted from the light emitting elements 3 is fluorescent. Radiated through the body layer 4Y. In this case, the blue light emitted from the light emitting element 3 excites the yellow phosphor, is converted from the yellow phosphor to yellow fluorescence, and is transmitted to the outside through the phosphor layer 4Y. Further, of the blue light emitted from the light emitting element 3, the light that has not excited the yellow phosphor is directly transmitted through the phosphor layer 4Y and emitted to the outside. At this time, yellow light and blue light are mixed and irradiated as daylight color light having a correlated color temperature of 7000K to 5000K. Specifically, the correlated color temperature is set to 6700K.

  Further, when the second power supply line 21b is selected and energized by a changeover switch or the like on the power supply circuit side, the second light source B connected to the second power supply line 21b, that is, the second power supply line 21b is connected. The light emitting elements 3 are turned on all at once, and the light emitted from the light emitting elements 3 is emitted through the phosphor layer 4R. In this case, the blue light emitted from the light emitting element 3 excites the red phosphor in addition to exciting the yellow phosphor. As a result, red fluorescence is emitted, and the light transmitted through the phosphor layer 4R and emitted to the outside is irradiated as light bulb color light having a correlated color temperature of 3500K to 2500K with a redness component added. Specifically, the correlated color temperature is set to 2700K.

  Note that power may be supplied to both the first power supply line 21a and the second power supply line 21b by a changeover switch or the like on the power supply circuit side. In this case, all the light emitting elements 3 emit light, and both the first light source A and the second light source B are turned on, so that the correlated color temperature is intermediate between them.

  Thus, the light emitting device 1 can select the light emission color of daylight color light or light bulb color light by the first light source A and the second light source B, and the first light source A and the second light source B can be selected. Since the light sources B are arranged in a dispersed manner, the light sources B are used as planar light sources having a good uniformity as a whole in the irradiation of each emission color.

  In addition, since the first light source A and the second light source B have the same number of light emitting elements 3 and the same number of light emitting element rows, there is a large change in the light distribution state when either one is selected by switching. Does not occur.

  In addition, a plurality of light emitting elements 3 are arranged on the mounting pad 22 of the substrate 2 in a direction perpendicular to the longitudinal direction of the substrate 2 to form a light emitting element array. The desired output can be obtained by appropriately selecting the increase / decrease.

  During the light emission of the light emitting element 3, the mounting pad 22 functions as a heat spreader that diffuses the heat generated by each light emitting element 3. During the light emission of the light emitting device 1, the light emitted from the light emitting element 3 toward the substrate 2 is reflected mainly by the surface layer of the mounting pad 22 in the light utilization direction. Therefore, the light extraction efficiency can be improved. In addition, the light emitted in the lateral direction among the light emitted from the light emitting element 3 is reflected by the surface of the white resist layer 23 having a high reflectance and is emitted to the front side.

  As described above, according to the present embodiment, it is possible to provide the light emitting device 1 and the illumination device 11 that can change the emission color and have good uniformity of the irradiation light as a whole.

  Next, a second embodiment of the present invention will be described with reference to FIG. The figure shows the arrangement of the first power supply line 21 a, the second power supply line 21 b, and the light emitting elements 3 on the substrate 2. Note that the same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  Nine parallel circuits in which six light emitting elements 3 are connected in parallel are connected in series to the first power supply line 21a. Similarly, nine parallel circuits in which six light emitting elements 3 are connected in parallel are connected in series to the second power supply line 21b.

  The first power supply line 21a and the second power supply line 21b form an independent electric power supply path, and the first power supply line 21a and the second power supply line 21b are connected to each other by a changeover switch or the like provided on the power supply circuit side. The second power supply line 21b can be selectively switched.

According to such a configuration, in addition to the effects of the first embodiment, the currents flowing through the parallel circuits are equal, and variations in light output and emission color between the parallel circuits are reduced, so that the irradiation light as a whole can be reduced. The uniformity can be improved.
Next, a third embodiment of the present invention will be described with reference to FIG. Note that the same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the present embodiment, the first light source A and the second light source B are alternately and dispersedly arranged in a direction orthogonal to the longitudinal direction of the substrate. The phosphor layer 4 has a mountain shape and individually covers the light emitting elements 3.

  Even with such a configuration, it is possible to change the emission color by switching between the first light source A and the second light source B, and the uniformity of the irradiated light as a whole can be improved.

  The present invention is not limited to the configuration of each of the embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, the light emitting element is a solid light emitting element such as an LED. Further, the number of mounted light emitting elements is not particularly limited.

  Further, when a light emitting color of a light bulb is obtained as the second light source, for example, blue light emitting elements and red light emitting elements are alternately arranged and covered with a phosphor layer containing a yellow phosphor. You may comprise as follows. As a result, it is possible to emit the light bulb color that compensates for the shortage of the red component.

The light source is not limited to two types. That is, not only the selective switching of the daylight color and the light emission color of the light bulb color, but also a day white color, white color, and warm white color may be added to change them.
Furthermore, although the white color is suitable for the emission color, the present invention is not limited to this. For example, the daylight color and the blue light may be selectively changed.
The lighting device can be applied to lighting fixtures, display devices, and the like used indoors or outdoors.

DESCRIPTION OF SYMBOLS 1 ... Light-emitting device, 2 ... Board | substrate, 3 ... Light emitting element (LED chip),
4 ... sealing member (phosphor layer), 4Y ... phosphor layer containing yellow phosphor,
4R: phosphor layer mixed with red phosphor, 21a: first feeding line,
21b ... 2nd electric power feeding line, 11 ... Illumination device, A ... 1st light source,
B ... Second light source

Claims (4)

A substrate;
A first power supply line and a second power supply line formed on the substrate;
A plurality of light emitting elements connected to the first power supply line and mounted on the substrate; and a sealing member that covers the plurality of light emitting elements, and that emits light having a predetermined correlated color temperature. With a light source;
A plurality of light emitting elements connected to the second power supply line and mounted on the substrate; and a sealing member that covers the plurality of light emitting elements, and having a correlation different from a correlated color temperature of the first light source A second light source that emits light of a color temperature;
And the first light source and the second light source are distributed on the substrate.   The correlated color temperature of light emitted from the first light source is set to 7000K to 4500K, and the correlated color temperature of light emitted from the second light source is set to 3500k to 2500K. Item 4. The light emitting device according to Item 1.   3. The light emitting device according to claim 1, wherein the first light source and the second light source are arranged in a plurality of rows in a direction orthogonal to a longitudinal direction of the substrate. . The device body;
The light emitting device according to any one of claims 1 to 3, wherein the light emitting device is disposed in the device body;
An illumination device comprising:

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