JP2015226002A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device capable of adjusting color tone of light emission while reducing color unevenness during color tone adjustment.SOLUTION: The light-emitting device includes: a light emitting element; a wavelength conversion member containing a wavelength conversion material that absorbs light emitted by the light emitting element and emits light having a different wavelength; a deformation member capable of deforming a shape of the wavelength conversion member; and a holding member for holding a surface shape of the wavelength conversion member during the time of deformation.

Description

  The present invention relates to a light emitting device including a light emitting element and a wavelength conversion member, and relates to a technique for adjusting chromaticity by suppressing light emission unevenness of the light emitting device.

  In recent years, light-emitting devices using a combination of a light-emitting element chip (light-emitting element) and a phosphor that absorbs light from the light-emitting element and emits light of different wavelengths are used in various lighting devices. . Since such light emitting devices have variations in chips, phosphors, and the like, light emitting devices that are obtained in the same manner have different chromaticities.

  In order to solve this problem, in the past, contrivances have been made to suppress the variation in the manufacturing process of the light emitting device, but the chromaticity is adjusted after manufacturing instead of strictly managing the chromaticity in the manufacturing process. Technology has also been proposed.

  For example, Patent Literature 1 provides a technique for adjusting chromaticity by changing the thickness of a wavelength conversion member that seals a light emitting element.

The above technique is to reversibly adjust the chromaticity by changing the thickness in the light irradiation direction by pressing the wavelength conversion member.
There is also a demand for adjusting the color tone of light emission after the light emitting device is manufactured, for example, during use of an illumination device incorporating the light emitting device.

JP 2011-171358 A

  However, in the chromaticity adjustment method shown above, since there is no mechanism for controlling the deformed shape of the wavelength conversion member, particularly the shape of the surface on the light emitting surface side of the wavelength conversion member, the emission color differs unintentionally (color There is a problem that unevenness occurs.

 The present invention has been made in view of the above problems, and an object of the present invention is to provide a light-emitting device that can adjust the color tone of light emission while reducing color unevenness when adjusting the color tone.

  One aspect of the present invention includes a light-emitting element and a wavelength conversion member including a wavelength conversion material that emits light of different wavelengths by absorbing light emitted from the light-emitting element, and deforming the shape of the wavelength conversion member A light emitting device comprising a deformable member and a holding member that maintains a surface shape of the wavelength conversion member during the deformation.

  Accordingly, it is possible to provide a light emitting device that can adjust the color tone of light emission while reducing color unevenness.

It is a sectional side view explaining one embodiment of the present invention. It is a sectional side view explaining the state which changed the wavelength conversion member regarding one embodiment of the present invention. It is a sectional side view explaining an example of the holding member of this invention. It is a sectional side view explaining an example of the holding member and wavelength conversion member of this invention. It is a sectional side view explaining one embodiment of the present invention. It is a sectional side view explaining the state which changed the wavelength conversion member regarding one embodiment of the present invention. It is a sectional side view explaining one embodiment of the present invention. It is a sectional side view explaining the state which changed the wavelength conversion member regarding one embodiment of the present invention. It is a sectional side view explaining one embodiment of the present invention. It is a sectional side view explaining the state which changed the wavelength conversion member regarding one embodiment of the present invention. It is a top view explaining regarding one embodiment of the present invention. It is a top view explaining the state which changed the wavelength conversion member about one embodiment of the present invention.

  A mode for carrying out the present invention will be described below with reference to the drawings. However, the form shown below illustrates the light emitting element with a covering member and the light emitting device for embodying the technical idea of the present invention, and is not limited to the following. In addition, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only. It should be noted that the size and positional relationship of the members shown in each drawing may be exaggerated for clarity of explanation.

(Embodiment 1)
The structure of the light emitting device according to the first embodiment of the present invention will be described with reference to FIG . FIG. 1 is a side sectional view showing an embodiment of a light emitting device of the present invention. This light-emitting device has a light-emitting element 13 such as an LED chip mounted on a substrate 11 on which a conductor pattern is formed.

  Further, on the substrate 11, the wavelength conversion member 15 that covers the light emitting element 13 (more specifically, the upper surface serving as the light emitting surface of the light emitting element 13 and the side surface of the light emitting element 13), and the wavelength converting member 15 are deformed. And a deformable member 19 that can be deformed. The deformation member 19 of the present embodiment surrounds the side surface of the wavelength conversion member 15 and is disposed so as to be in close contact with the side surface of the wavelength conversion member. The light emitting surface side surface (upper surface) of the wavelength conversion member 15 is substantially flat.

In addition, a translucent holding member 17 is provided above the wavelength converting member 15 in order to hold the surface shape of the wavelength converting member 15 in the light irradiation direction. In the present embodiment, since the holding member 17 is supported above the wavelength conversion member 15, the deformable member 19 also serves as a support portion that supports the holding member 17.
As shown in FIG. 1, the surface (contact surface) facing the wavelength conversion member 15 of the holding member 17 is substantially flat. In addition, when the wavelength conversion member 15 is not deformed, the wavelength conversion member 15 and the holding member 17 are separated from each other.

  As shown in FIG. 2, the wavelength conversion member 15 is pressed from the side surface direction by the deformation member 19 by moving the deformation member 19 toward the center of the light emitting device, and the wavelength conversion member 15 is deformed. At this time, the thickness of the wavelength conversion member 15 in the light irradiation direction changes. In this deformation, the holding member 17 (more specifically, the contact surface of the holding member 17) comes into contact with the upper surface of the wavelength conversion member 15, so that the surface shape of the wavelength conversion member is the same as the contact surface with the holding member. It can be held in shape.

  As described above, the color tone of light emission can be adjusted while maintaining the surface shape of the wavelength conversion member.

  Depending on the shape of the holding member 17, the surface shape of the wavelength conversion member 15 can be arbitrary. For example, in the above embodiment, the shape of the contact surface of the holding member 17 is substantially the same as the surface shape of the wavelength conversion member 15 before deformation, but may be different from the surface shape before deformation. For example, as shown in FIG. 3A, by making the contact surface of the holding member 17 a curved surface, as shown in FIG. 3B, the surface shape at the time of deformation of the wavelength conversion member 15 is made to correspond to the curved surface of the holding member. be able to.

(Embodiment 2)
The structure of the light emitting device according to the second embodiment of the present invention will be described with reference to FIG. This light-emitting device includes a wavelength conversion member 15 on a substrate 11 and further includes a holding member 17 that presses from the light irradiation direction while holding the surface shape of the wavelength conversion member 15. In this embodiment, the holding member 17 also serves as a deforming member, and the holding member 17 includes a translucent pressing surface 18 that presses the wavelength conversion member 15.
In order to support the holding member 17, a support unit 20 connected to the substrate 11 and supporting the holding member 17 is provided.
The pressing surface 18 of the holding member 17 is disposed above the wavelength conversion member 15, and the support portion 20 that supports the holding member 17 is disposed around the wavelength conversion member 15. In FIG. 4, the pressing surface is in contact with the wavelength conversion member 15, but may be arranged in a separated state.

As shown in FIG. 5, the pressing surface 18 for pressing the wavelength conversion member of the holding member 17 moves along the support portion 20 from the upper surface side of the light emitting device to the wavelength conversion member 15 side, and the wavelength conversion member 15 is moved. By pressing and deforming, the thickness of the wavelength conversion member 15 in the light irradiation direction changes. Even in this case, at least a part of the surface shape of the wavelength conversion member 15 can be limited to the shape of the contact surface of the holding member 17 and can be held.

  As an example of a method for moving the holding member 17 that also serves as a deformable member, there is a method in which the holding member 17 is moved in conjunction with a motor or pressurized with air.

(Embodiment 3)
As shown in FIG. 6, the side surface shape of the wavelength conversion member 15 is maintained by providing the support portion 20 also serving as a holding member on the side surface of the wavelength conversion member 15 and making it a shape corresponding to the shape of the wavelength conversion member 15. It can be deformed as it is. At this time, the recess 12 may be provided on the substrate 11.

By providing the recess 12 on the substrate 11, when the wavelength conversion member 15 is pressed and deformed from above by the pressing surface 18, a part of the wavelength conversion member 15 is accommodated in the recess 12. Thereby, thickness can be made thin in the state which hold | maintained the shape of the upper surface and side surface of the wavelength conversion member 15. FIG. On the other hand, the light irradiation direction side of the wavelength conversion member 15 is held by the pressing surface 18, and the side surface is held by the surface 20 that also serves as a support portion.
As described above, it is possible to adjust the color tone of light emission while reducing the color unevenness by deforming the wavelength conversion member 15 while maintaining not only the light irradiation direction but also the shape of the side surface.

  In the present embodiment, the color tone of light emission can be adjusted while maintaining the shape of the light emitting surface and the side surface of the wavelength conversion member.

(Embodiment 4)
The structure of the light emitting device according to the fourth embodiment of the present invention will be described with reference to FIGS. This light emitting device has a support member 20 that also serves as a holding member on the side surface of the wavelength conversion member 15 in addition to the holding member 17 that also serves as a deforming member on the upper surface of the wavelength conversion member 15.
The wavelength conversion member 15 has a shape that widens toward the upper side of the light emitting device (that is, the side surface of the wavelength conversion member 15 is inclined with respect to the substrate 11), and the support portion 20 is the side surface of the wavelength conversion member 15. It has a side surface that substantially matches the shape. A part 20 ′ of the support part can move on the substrate 11 in the lateral direction.

  As shown in FIG. 9, the upper surface of the wavelength conversion member 15 is pressed and deformed from above the light emitting element by the pressing surface 18 of the holding member 17 to change the thickness of the wavelength conversion member 15 in the light irradiation direction. At the time of this deformation, a part 20 ′ of the support part moves horizontally from the center of the light emitting device toward the outer side on the substrate 11 while maintaining the angle of the side surface of the wavelength conversion member 15.

Examples regarding the positional relationship between the wavelength conversion member 15 and the support portion 20 are shown in FIGS. 10A and 10B. FIG. 10B is a top view after the wavelength conversion member 15 is pressed and deformed before the wavelength conversion member 15 is pressed in FIG. 10A.
The support part 20 is divided into four parts, has a rectangular shape with each of the four parts as one side in a top view, and surrounds the rectangular wavelength conversion member 15.
When the wavelength conversion member 15 is pressed and deformed, the support portion 20 is pressed, and the two opposite sides indicated by 20 ′ in FIG. 10B move, so that the side surface shape of the wavelength conversion member 15 is maintained and the light irradiation direction is maintained. The thickness can be changed.

  According to the above method, in Embodiment 4, the color tone of light emission can be adjusted while maintaining the surface of the wavelength conversion member and the inclined side shape.

Next, the structure of the light emitting device and each component of the present invention will be described in detail below.

(Light emitting device)
The light emitting device of the present invention is a surface mount type light emitting diode or bullet type light emitting diode in which a light emitting element is accommodated in a package having positive and negative lead electrodes, a reflecting member, etc., and a resin or phosphor layer is formed around the light emitting element. A chip size package type light emitting diode or the like can be used.

  Note that the light-emitting element includes, for example, a p-type semiconductor layer, an active layer that emits light, an n-type semiconductor layer, a p-side electrode electrically connected to the p-type semiconductor layer, an n-type semiconductor layer, and an electric N-side electrode connected to each other. The electrodes of the light emitting element are electrically connected to the positive and negative lead electrodes by die bonding, wire bonding, flip chip bonding, or the like. Further, the electrode of the light emitting element may be a lead electrode that is exposed to the outside of the light emitting device and bonded to a mounting substrate or the like.

  The light-emitting element is directly covered with the wavelength conversion member 15 or a member that deforms with the deformation of the wavelength conversion member (for example, a translucent layer provided below the wavelength conversion member and on the light-emitting element). In some cases, the light emitting element is preferably mounted by flip chip bonding without using a wire or the like. This can reduce the risk of disconnection of the light emitting element.

  As the light emitting element, for example, a light emitting element that emits blue or violet light, for example, a light emitting element in which a GaN-based semiconductor is stacked on a sapphire substrate can be used. Thus, a white light emitting device can be easily manufactured in combination with a wavelength conversion member described later.

(Wavelength conversion member)
The light emitting device includes not only light emitted from the light emitting element but also a wavelength conversion member that absorbs the emitted light and emits light of different wavelengths. The emission color (emission color tone) from the light emitting device is a combination of the emission from these light emitting elements and the emission from the wavelength conversion member.

  The wavelength conversion member contains a wavelength conversion material. As the wavelength conversion material, for example, a phosphor can be used. The phosphor is provided in the light emitting device by various methods. For example, it can be contained in a translucent sealing member that seals the light emitting element.

  Various phosphors can be used as long as the phosphor can absorb light from the light emitting element and emit light of another wavelength. For example, nitride phosphors and oxynitride phosphors mainly activated by lanthanoid elements such as europium and cerium, more specifically, α or β sialon phosphors activated by europium, various alkalis Earth metal nitride silicate phosphors, lanthanoid elements such as europium, alkaline earth metal halogenapatite phosphors mainly activated by transition metal elements such as manganese, alkaline earth halosilicate phosphors, alkaline earth metals Silicate phosphor, alkaline earth metal halogen borate phosphor, alkaline earth metal aluminate phosphor, alkaline earth metal silicate, alkaline earth metal sulfide, alkaline earth metal thiogallate, alkaline earth metal nitride Rare earth aluminate mainly activated by lanthanoid elements such as silicon, germanate, cerium, Examples thereof include organic substances and organic complexes mainly activated with lanthanoid elements such as rare earth silicates or europium. In particular, when combined with a blue light emitting element, a yellow phosphor YAG phosphor, a red phosphor SCASN or KSF, a green phosphor β-SiAlON, a LAG phosphor, or the like is preferably used. As a result, a light emitting device of white or light bulb color can be manufactured.

  Two or more kinds of phosphors may be used for one light emitting device. Two or more types of phosphors. It may be provided in a mixed state or may be provided in layers.

  In order to arbitrarily adjust the chromaticity, the deformation of the wavelength conversion member is preferably reversible. Therefore, when the wavelength conversion member is solid, it is preferable to have elasticity or toughness. For example, it can be used as a translucent rubber-like resin or a sealing member.

  Further, the wavelength conversion member 15 may be liquid. Thereby, when the wavelength conversion member 15 is deformed, the chromaticity can be adjusted, which can reduce the concern that the wavelength conversion member 15 is broken and the fear that the light-emitting element 13 is broken when it is deformed. it can.

The sealing member may include a filler such as silica or titanium oxide in the sealing member as necessary.

(Deformation member)
The deformation member is a member for deforming, which can deform the wavelength conversion member. The material and the position of the deformable member are not particularly limited, and are appropriately selected depending on the shape of the wavelength conversion member to be deformed and the structure of the light emitting device.

In order to adjust the chromaticity by deforming the wavelength conversion member, it is necessary to arbitrarily adjust the deformation amount of the wavelength conversion member. Therefore, the deformation member needs to be able to arbitrarily adjust the amount of pressurization.
As a mechanism for driving the deformable member in this manner, for example, a piezoelectric actuator provided with a piezoelectric element, a motor, pressurized air, or the like can be used.

(Holding member)
The holding member may be a member that is provided at least above the wavelength conversion member and transmits light emitted from the light emitting element or light emitted from the wavelength conversion member while holding the surface shape of the wavelength conversion member. . Moreover, since pressure is applied when the wavelength conversion member is deformed, a highly rigid substance is preferable so that the holding member does not deform.

  As the holding member, for example, translucent glass or resin can be considered.

  The holding member may also serve as a deformation member that deforms the wavelength conversion member. For example, the wavelength conversion member may be pressed and deformed by a pressing portion of a holding member provided above the wavelength conversion member.

When the holding member also serves as a deforming member, for example, the pressing surface is moved in conjunction with the motor, or the upper surface side (the side not in contact with the wavelength conversion member) of the pressing surface is moved in a pressurized atmosphere, thereby changing the wavelength. The conversion member can be pressed and deformed.

  The holding member may be provided not only above the wavelength conversion member but also on the side. At this time, the support part which supports the holding member above the wavelength conversion member may also serve as the holding member.

  In addition, the light emitting device may be, for example, a combination of a plurality of light emitting elements that emit light of different colors and a phosphor. Specifically, light green (whiteish green) light is obtained from a light-emitting device using a light-emitting element that emits blue light and a phosphor that absorbs blue light and emits green light. Light from a light emitting device having a light emitting element may be mixed to obtain white region light.

  Note that variation in chromaticity of the light emitting device occurs due to various causes. For example, the amount and distribution of the phosphor, the emission wavelength of the light emitting element, the mixing ratio of the phosphor, the viscosity variation of the resin containing the phosphor, the consumption and the variation of various devices such as the manufacturing device and the measuring device, etc. Caused by a cause.

  As mentioned above, although the form for implementing this invention was demonstrated about the chromaticity adjustment method of a light-emitting device, this invention is not limited to the said embodiment, Based on these description, various changes, a modification | change, etc. were carried out. Needless to say, these are also included in the spirit of the present invention.

  In addition, the configuration described in one embodiment of the present specification can be applied to another embodiment unless particularly difficult.

DESCRIPTION OF SYMBOLS 11 Substrate 12 Recess 13 on substrate surface Light emitting element 15 Wavelength conversion member 17 Holding member 18 Pressing surface 19 Deformation member 20, 20 '

Claims (8)

A wavelength conversion member including a light-emitting element and a wavelength conversion material that emits light of different wavelengths by absorbing light emitted from the light-emitting element;
A light emitting device comprising: a deformable member capable of deforming a shape of the wavelength converting member; and a holding member that maintains a surface shape of the wavelength converting member at the time of the deformation on an upper surface of the wavelength converting member. apparatus. The wavelength conversion member is provided on a light emitting surface side of the light emitting element, and the holding member is a translucent member having a shape corresponding to a surface shape of the wavelength conversion member. The light emitting device described. The light emitting device according to claim 1, wherein the holding member also serves as the deformation member. The light emitting device according to claim 3, further comprising a support portion that supports the holding member. The light emission according to any one of claims 1 to 3, wherein the holding member is also provided on a side of the wavelength conversion member. 6. The light emitting device according to claim 5, wherein the holding member provided on a side of the wavelength conversion member moves outward from the center of the light emitting device during the deformation. The light emitting device according to claim 1, wherein the wavelength conversion member is in a liquid state. 8. The light emitting device according to claim 1, wherein the light emission color of the light emitting device can be changed by changing the shape of the wavelength conversion member by the deformable member. 9. .

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