JP2013201298A - Light-emitting device and lighting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device capable of suppressing deterioration in luminous efficiency, and a lighting apparatus provided with the light-emitting device.SOLUTION: A light-emitting device 1 of the present embodiment includes: a protruding first phosphor layer 4 which is provided on one surface side of a substrate 2 so as to cover part of an upper surface and a side surface of an LED 3; and a second phosphor layer 5 which is provided on the one surface side of the substrate so as to cover those portions of the upper surface and the side surface of the LED 3 which are not covered with the first phosphor layer 4, and converts light emitted from the LED 3 into light having a wavelength different from that of light converted by the first phosphor layer 4.

Description

  One embodiment of the present invention relates to a light emitting device using a light emitting element as a light source and an illumination device including the light emitting device.

  Conventionally, for example, a light emitting device including a plurality of light emitting elements encloses the light emitting elements mounted on a substrate with a bank or a frame and seals the light emitting elements with a sealing resin containing a phosphor filled inside the bank. It has stopped. As the phosphor, a yellow phosphor that emits yellow light excited by blue light emitted from a light emitting element is used (see, for example, Patent Documents 1 and 2).

  However, in a light-emitting device using only a yellow phosphor as a phosphor, the color rendering properties are inferior because red and blue-green light components are insufficient. Therefore, in order to improve the color rendering, a particulate red phosphor that emits red light when excited by the light of the blue LED may be mixed with the particulate yellow phosphor several percent.

JP 2011-54303 A (Page 7, FIG. 2) JP 2011-35431 A (Page 8, FIG. 1)

  By the way, it is known that the red phosphor has a property of absorbing green light and yellow light. When red phosphors are mixed to improve color rendering, the probability that the particulate red phosphors randomly dispersed over the entire area of the yellow phosphor and the particulate yellow phosphors are adjacent at a close distance Is expensive. For this reason, a part of yellow light emitted from the yellow phosphor excited by blue light is easily absorbed by the red phosphor positioned around the yellow phosphor, resulting in a decrease in light output. In other words, the luminous efficiency of white light is reduced.

  An object of an embodiment of the present invention is to provide a light emitting device capable of suppressing a decrease in luminous efficiency and an illumination device including the light emitting device.

  The light emitting device according to the embodiment of the present invention includes a substrate, a light emitting element, a first phosphor layer, and a second phosphor layer.

  The substrate is provided with a mounting portion on one side thereof. The light emitting element is mounted on the mounting portion of the substrate. The first phosphor layer and the second phosphor layer are provided on one surface side of the substrate so as to cover at least a part of the upper surface and the side surface of the light emitting element.

  According to the embodiment of the present invention, the first phosphor layer and the second phosphor layer each have a convex shape and are provided so as to cover the common light emitting element with different regions. A part of the light emitted from the body layer is not easily absorbed by the other phosphor layer, and it can be expected to suppress a decrease in luminous efficiency.

1 is a schematic top view of a light emitting device showing a first embodiment of the present invention. Similarly, it is a partial expansion schematic top view which shows the mounting part of a light-emitting device. Similarly, it is a schematic sectional drawing of the mounting part of a light-emitting device. It is a schematic perspective view of the illuminating device which shows the 2nd Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described.

  The light emitting device 1 of the present embodiment is configured as shown in FIGS. In addition, in each figure, the same code | symbol is attached | subjected to the same part and the overlapping description is abbreviate | omitted.

  In FIG. 1, the light emitting device 1 includes a substrate 2, an LED 3 as a light emitting element, and first and second phosphor layers 4 and 5.

  The substrate 2 is made of a synthetic resin, for example, a glass epoxy material, and is formed into a long rectangle whose one surface 2a and the other surface 2b (shown in FIG. 3) are planar.

  And the board | substrate 2 is provided with the mounting part 6 in which LED3 is mounted and the 1st fluorescent substance layer 4 and the 2nd fluorescent substance layer 5 are provided in the one surface 2a side. The mounting portions 6 are provided at equal intervals along the longitudinal direction of the substrate 2 and are provided in two rows. In addition, an input connector CN1 and a connection connector CN2 are disposed at both longitudinal ends 2c and 2d.

  At the center of each mounting portion 6, a circular base portion 7 having a thickness of, for example, 10 μm is provided by silver plating. On both sides of the base portion 7 in the short direction of the substrate 2, the wiring patterns 8 and 8 are formed so as to face each other for each group of the plurality of mounting portions 6. The wiring patterns 8 and 8 are connected in series by the wiring patterns 9 and 10, and one wiring pattern 8 at one end is electrically connected to the input connector CN1, and the other wiring pattern 8 at the other end is electrically connected to the connecting connector CN2. It is connected. Further, another wiring pattern 11 is connected to the input connector CN1 and the connection connector CN2. Each of the wiring patterns 8 to 11 is an example.

For example, a metal foil formed by screen printing, such as a copper foil or a silver foil, is formed to have a predetermined width having a thickness of 10 μm, for example. In addition, although the quantity of 1 group of the mounting parts 6 is two in FIG. 1, it is not restricted to this, Three or more may be sufficient.

  The connection connector CN2 is electrically connected to the input connector CN1 of the light emitting device 1 adjacent to the light emitting device 1 arranged in parallel by an electric connection means (not shown) such as a lead wire. The connection connector CN2 of the single light emitting device 1 or the rearmost light emitting device 1 arranged in parallel is electrically connected to the wiring patterns 8 and 11 so as to electrically connect the wiring pattern 8 and the wiring pattern 11. A terminal (not shown) is short-circuited by a short-circuit means such as a lead wire.

  A white resist 12 is formed on one surface 2a of the substrate 2 excluding the mounting portion 6, the input connector CN1, and the connection connector CN2 by, for example, screen printing. The white resist 12 protects the surface 12a of the white resist 12 from being a reflective surface and being deteriorated by touching the surfaces of the wiring patterns 8 to 11 with air.

  The LED 3 is formed in a known configuration, for example, in a substantially rectangular parallelepiped shape so as to emit blue light. The LED 3 is bonded to the base portion 7 and mounted on the mounting portion 6. As shown in FIG. 2, each LED 3 has its electrodes 3a and 3b connected to wiring patterns 8 and 8 by bonding wires 13 and 14, respectively.

  As shown in FIG. 1, a plurality of LEDs 3 are connected in parallel to the wiring patterns 8 and 8.

The LED 3 connected in parallel is connected to the input connector CN1 and the connection connector.

The kuta CN2 is connected in series. When a predetermined power is supplied to the input connector CN1 from a lighting device (not shown), a predetermined voltage is applied between the wiring patterns 8, 9 electrically connected to the input connector CN1, and the wiring patterns 8, 8 are connected. A predetermined DC voltage, for example, DC3V is generated between them, and a predetermined current flows through the LED 3. Thereby, LED3 light-emits (lights up) and radiates | emits blue light.

  The first phosphor layer 4 is made of translucent silicone resin, for example, and is provided on the one surface 2a side of the substrate 2 so as to cover part of the upper surface and side surface of the LED 3 and to cover the mounting portion 6 of the substrate 2. It has been. The first phosphor layer 4 is mixed with a yellow phosphor 15 at a predetermined ratio. The first phosphor layer 4 has a predetermined viscosity (fluidity) and thixotropy, and is provided on the one surface 2 a side of the substrate 2 by being dropped and solidified on the mounting portion 6 of the substrate 2.

  The second phosphor layer 5 is made of, for example, a silicone resin having translucency, covers the upper surface of the LED 3 that is not covered by the first phosphor layer 4, and the remaining region of the side surface, and the mounting portion of the substrate 2. 6 is provided on the one surface 2 a side of the substrate 2 so as to cover 6. The second phosphor layer 5 is mixed with a red phosphor 16 at a predetermined ratio. The second phosphor layer 5 has a predetermined viscosity (fluidity) and thixotropy, and is provided on the one surface 2 a side of the substrate 2 by being dropped and solidified on the mounting portion 6 of the substrate 2. Furthermore, the second phosphor layer 5 is formed so as to have a higher refractive index than the translucent resin of the first phosphor layer 4.

  As shown in FIGS. 2 and 3, the first and second phosphor layers 4 and 5 are dropped into the mounting portion 6 in a predetermined amount with a cross-sectional shape formed in a predetermined shape, for example, a hemispherical shape. Then, the dropped first and second phosphor layers 4 and 5 are solidified to form a hemispherical cross section. The shape of the first and second phosphor layers 4 and 5 is not limited to a hemispherical shape, and may be a predetermined shape such as a bullet shape or a semi-elliptical shape. The viscosity of the first and second phosphor layers 4 is set to a predetermined viscosity value that makes it difficult for the first and second phosphor layers 4 and 5 before solidification to flow along the surface 12 a of the white resist 12. The viscosity is preferably set in the range of 1 to 20 poise (P), more preferably 5 to 15 poise (P). Here, for example, 10 poise (P) first and second phosphor layers 4 and 5 are used.

  Next, the operation of the first embodiment of the present invention will be described.

  A predetermined amount of the first phosphor layer 4 is continuously dropped onto the LED 3 mounted on the mounting portion 6 of the substrate 2 in a state of having fluidity before being cured. The first phosphor layer 4 is blocked by an inner wall 12 b (shown in FIG. 3) of the white resist 12 and fills the mounting portion 6 surrounded by the white resist 12. And when it reaches the surface 12a side of the white resist 12, it tries to spread on the surface 12a, but has a predetermined viscosity and thixotropy, and acts against the spreading force that tries to spread from the white resist 12. Yes. Since the surface tension is generated, the first phosphor layer 4 flows along the surface 12a of the white resist 12 and does not spread. And the 1st fluorescent substance layer 4 is formed in a substantially circular arc shape with the position where the outer surface 4a side remove | deviated from on LED3 as a vertex by the surface tension and thixotropy. And the 1st fluorescent substance layer 4 is formed in the predetermined shape, for example, a hemispherical shape, by hardening | curing. The hardness after curing is Shore 40 or higher.

  Then, after the first phosphor layer 4 is cured, a predetermined amount is continuously dropped from the second phosphor layer 5 to the remaining portion of the LED 3 where the first phosphor layer 4 is not provided. At this time, the second phosphor layer 5 is in a state having fluidity before being cured in the same manner as the first phosphor layer 4. Since the second phosphor layer 4 after that is blocked by the inner wall 12b (shown in FIG. 3) of the white resist 12 similarly to the first phosphor layer 4, it has a predetermined viscosity and thixotropy. A resistance against the spreading force to spread from the white resist 12 acts. And the 2nd fluorescent substance layer 5 is formed in the substantially circular arc shape with the position which the outer surface 5a side wants to remove | deviate from on LED3 by the surface tension and thixotropy, but the location adjacent to the 1st fluorescent substance layer 4 Is dammed by the first phosphor layer 4, and is formed in a concave shape when viewed from above. And the 2nd fluorescent substance layer 5 is formed in arbitrary shapes by hardening | curing in such a state. The hardness after curing is Shore 40 or higher.

  In the light emitting device 1, when predetermined power is supplied to the input connector CN1 of the substrate 2, the LED 3 emits light and blue light is emitted. A part of the blue light is wavelength-converted into yellow light by the yellow phosphor 15 mixed in the first phosphor layer 4. Then, white light in which blue light and yellow light are mixed is emitted outward from the outer surface 4 a of the first phosphor layer 4. Further, part of the blue light emitted from the LED 3 also enters the second phosphor layer 5. Then, the red phosphor 16 mixed in the second phosphor layer 5 is wavelength-converted to red light, and mainly the red light is emitted outward from the outer surface 5 a of the second phosphor layer 5.

  According to this embodiment, since the first phosphor layer 4 is not mixed with the red phosphor 16, the first phosphor layer 4 is excited and wavelength-converted, and yellow light is reabsorbed by the red phosphor. Therefore, it is possible to suppress a decrease in the luminous efficiency of the white light emitted from the first phosphor layer 4.

  Further, since the first phosphor layer 4 and the second phosphor layer 5 are provided separately, each phosphor is compared with the case where the yellow phosphor 15 and the red phosphor 16 are mixed in one translucent resin. There is no variation in the dispersion state. Regarding this point, when using yellow phosphor 15 and red phosphor 16 having different specific gravities, if they are mixed in one translucent resin, the degree of sedimentation of each phosphor varies depending on changes over time in the manufacturing process. The color of light emitted from each light emitting device 1 may be different. However, according to the present embodiment, since the phosphor layers 4 and 5 are separated, the color variation caused by the degree of phosphor dispersion is less likely to occur.

  In the present embodiment, the angular color difference due to sedimentation or dispersion is reduced as described above. Supplementing this point, as compared with the case where different kinds of phosphors are mixed in the common phosphor layer as described above, the problem of the angular color difference caused by the difference in the degree of sedimentation and the dispersion state is less likely to occur. This is because when different types of phosphor layers are mixed in a common phosphor layer, the color difference between the side surface and the front surface is likely to change depending on the dispersion or sedimentation state. , 5 is relatively stable in color, so that the color difference of the light emitted from the light emitting device 1 can be reduced.

  Moreover, in this embodiment, it is comprised so that the refractive index of the 2nd fluorescent substance layer 5 may become high compared with the 1st fluorescent substance layer 4. FIG. Therefore, light emitted from the second phosphor layer 5 that is a layer having a high refractive index is likely to enter the first phosphor layer 4, but light that is emitted from the first phosphor layer 4 that is a layer having a low refractive index is It becomes difficult to enter the second phosphor layer 5. Therefore, in the first phosphor layer 4, red light emitted from the second phosphor layer 5 is incident so that red is mixed in addition to blue light and yellow light in the first phosphor layer 4. Therefore, light in a state where a plurality of colors are well mixed is emitted from the first phosphor layer 4 to the outside.

  On the other hand, light from the first phosphor layer 4 which is a layer having a low refractive index is difficult to enter the second phosphor layer 5. That is, since the light converted into yellow light by the first phosphor layer 4 does not enter the second phosphor layer 5 in which the red phosphor 16 is mixed, the yellow light is reabsorbed by the red phosphor 16. It is easy to improve efficiency.

  In the present embodiment, the second phosphor layer 5 is blocked by the first phosphor layer 4 so that the second phosphor layer 5 is partially concave. A method of simultaneously forming the layers 4 and 5 may also be used. In this case, it is assumed that adjacent areas of the first and second phosphor layers 4 and 5 may have a region where each phosphor layer is mixed, but if the mixed region is slightly formed, There is no significant difference in the operation and effect of this embodiment.

  Next, a second embodiment of the present invention will be described.

  FIG. 4 shows an illumination device according to the second embodiment. The straight tube light emitting lamp 24 is attached to the lighting device 31. The illuminating device 31 is directly attached to the ceiling surface, and is formed by including a straight tube type light emitting lamp 24, an appliance main body 32 as a device main body, and a lighting device 33. The instrument main body 32 is formed of a cold rolled steel plate or the like.

  The appliance main body 32 has sockets 34a and 34b to / from which the straight tube light-emitting lamp 24 is attached / detached at both end sides 32a and 32b in the longitudinal direction. One socket 34a is formed in a structure in which a pair of power feeding contacts (not shown) provided on the base of the straight tube light emitting lamp 24 are inserted and connected. The other socket 34b is formed in a structure in which one grounding contact (not shown) provided on the base of the straight tube light emitting lamp 24 is inserted and connected.

  The instrument body 32 includes a base (not shown) attached to the ceiling surface with screws or the like, and a reflector 35 fixed to the base with screws (not shown) via an attachment member (not shown). The base is formed in a long and substantially rectangular shape, and the reflector 35 is formed in a box shape that is long and has a substantially pentagonal cross section perpendicular to the longitudinal direction.

  The lighting device 33 is attached to the base. The lighting device 33 has an input line (not shown) connected to an external commercial AC power source. A pair of output lines (not shown) is connected to one socket 34a, and a ground line (not shown) is connected to the other socket 34b. Thus, the lighting device 33 is disposed in the appliance main body 32. The lighting device 33 is formed by a known configuration that supplies a predetermined current to the straight tube light emitting lamp 24 to light the LED 3 of the light emitting device 1.

  Inside the straight tube light emitting lamp 24, the light emitting device 1 shown in the first embodiment is disposed on a substrate (not shown), and when a predetermined power is supplied to the substrate, the LED 3 of the light emitting device 1 is Lights up (emits light) and light is emitted from the outer surfaces 4 a and 5 a of the first phosphor layer 4 and the second phosphor layer 5. This light passes through the translucent tube body 26 and passes through the tube body 26.

The light is emitted from the outer surface 26a to the external space.

  Similar to the effect of the first embodiment, the straight tube-type light emitting lamp 24 of this embodiment can suppress variation in color light, can obtain light with high luminous efficiency, and emits radiated light in a predetermined direction with a predetermined color light. It has the effect that it can radiate | emit and can illuminate a target object and a to-be-illuminated space.

    Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Light-emitting device, 3 ... LED as a light emitting element, 4 ... 1st fluorescent substance layer, 5 ... 2nd fluorescent substance layer,
31 ... Lighting device

Claims (3)

A substrate having a mounting portion on one side;
A light emitting element mounted on the mounting portion;
A convex first phosphor layer provided on one surface side of the substrate so as to cover part of the upper surface and side surfaces of the light emitting element;
Provided on one surface side of the substrate so as to cover at least part of the upper surface and the side surface of the light emitting element not covered by the first phosphor layer, and has a wavelength different from that of the first phosphor layer due to light emission from the light emitting element. A convex second phosphor layer that converts the light into
A light-emitting device comprising:   The light emitting device according to claim 1, wherein the plurality of phosphor layers are configured to have different refractive indexes. A generator according to claim 1 or 2;
An apparatus main body provided with a light emitting device;
A lighting device for lighting the light emitting element;
An illumination device comprising:

Images