JP3153795U - Light emitting diode - Google Patents

Abstract

A light emitting diode capable of changing the irradiation range of light emitted from an LED chip is realized. An LED chip, a translucent elastic body disposed above the LED chip, and a spherical surface disposed above the translucent elastic body and facing the translucent elastic body. The light-emitting diode 10 includes a translucent dome-shaped member 48 having an outer surface 46, and the spherical outer surface 46 of the dome-shaped member 48 is translucent elastic body by moving the dome-shaped member 48 in the vertical direction. The transparent elastic body 38 is elastically deformed into a concave shape to form a concave lens, and the contact area of the spherical outer surface 46 that contacts and presses the transparent elastic body 38 is changed. [Selection] Figure 1

Description

  The present invention relates to a light emitting diode capable of changing an irradiation range of light emitted from an LED chip.

FIG. 12 shows a light emitting diode according to Japanese Patent Application Laid-Open No. 2006-60099 proposed by the present applicant. This LED 70 is formed by connecting and fixing an LED chip 74 on a substrate 72 made of an insulating material. A pair of external electrodes 76a and 76b extending from the front surface of the substrate 72 through the side surface to the back surface are formed in a state of being insulated from each other.
One electrode (not shown) on the upper surface of the LED chip 74 is connected to one external electrode 76a via a bonding wire 78, and the other electrode (not shown) on the upper surface of the LED chip 74 is bonded. The wire 78 is connected to the other external electrode 76b.

On the LED chip 74, a sheet-like nonwoven fabric 82 carrying a phosphor 80 is disposed.
The LED chip 74 is surrounded by a frame member 84 having a predetermined height disposed on the substrate 72, and is formed by filling the frame member 84 with a translucent material such as an epoxy resin. It is sealed with a translucent lid member 86.

In the LED 70, when a voltage is applied to the LED chip 74 through the pair of external electrodes 76a and 76b, the LED chip 74 emits light, such as ultraviolet light or blue visible light that excites the phosphor 80. Light is emitted. This light is wavelength-converted to visible light of a predetermined color by the phosphor 80 carried on the nonwoven fabric 82 disposed on the LED chip 74, and is transmitted to the outside through the translucent lid member 86. is there.
JP 2006-60099 A

  By the way, in the above-described conventional LED 70, the irradiation range of the light transmitted through the translucent cover member 86 and radiated to the outside is always constant and cannot be changed.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to realize a light emitting diode capable of changing the irradiation range of light emitted from an LED chip.

In order to achieve the above object, the light-emitting diode according to claim 1 comprises:
LED chip, translucent elastic body disposed above LED chip, translucent dome shape having spherical outer surface disposed above translucent elastic body and opposed to translucent elastic body A light emitting diode comprising a member,
By moving the dome-shaped member in the vertical direction, the spherical outer surface of the dome-shaped member contacts and presses the translucent elastic body, and the translucent elastic body is elastically deformed into a concave shape to form a concave lens. The contact area of the spherical outer surface that contacts and presses the elastic elastic body is changed.

  The light-emitting diode according to claim 2 is the light-emitting diode according to claim 1, wherein the translucent elastic body is made of silicon rubber.

The light-emitting diode according to claim 3 is the light-emitting diode according to claim 1 or 2,
A phosphor that arranges a fiber assembly between the LED chip and the translucent elastic body, and converts the light emitted from the LED chip into light of a predetermined wavelength and emits the fiber aggregate to the fiber assembly. Is supported.

  A light-emitting diode according to a fourth aspect is the light-emitting diode according to the third aspect, wherein the aggregate of fibers is a nonwoven fabric, and a phosphor is supported on the fibers constituting the nonwoven fabric.

  In the light-emitting diode of the present invention, a light-transmitting elastic body is disposed above the LED chip, and the light-transmitting light has a spherical outer surface facing the light-transmitting elastic body above the light-transmitting elastic body. The dome-shaped member is arranged in a vertical direction so that the spherical outer surface of the dome-shaped member contacts and presses the translucent elastic body so that the translucent elastic body becomes concave. The lens is elastically deformed to form a concave lens, and the contact area of the spherical outer surface that contacts and presses the translucent elastic body is changed. Therefore, the contact area of the spherical outer surface is changed to make the translucent elastic body a concave lens. By changing the region, the irradiation range of the light emitted from the LED chip can be changed.

  Further, as in the light-emitting diode according to claim 3, a fiber assembly is disposed between the LED chip and the translucent elastic body, and light emitted from the LED chip is given to the fiber assembly in a predetermined manner. When a phosphor that converts and emits light of a wavelength is supported, the aggregate of fibers has a large surface area of the fiber per unit volume, so that a large amount of phosphor is supported and a large surface area per unit volume. Thus, a light-emitting diode with high brightness can be realized.

  Furthermore, the light-emitting diode according to claim 3, such as the light-emitting diode according to claim 4, wherein a non-woven fabric in which a large number of fibers are three-dimensionally entangled is used as a fiber assembly, and the fibers constituting the non-woven fabric When the phosphor is supported on the non-woven fabric, the nonwoven fabric has a very large surface area of the fiber per unit volume. A light emitting diode can be realized.

Hereinafter, embodiments of an LED according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view schematically showing an LED 10 according to the present invention. The LED 10 according to the present invention surrounds an LED chip 12 with a ring-shaped frame 14 and is exposed in the frame 14. The LED chip 12 is die-bonded to the leading end portion 16a of one lead frame 16, thereby electrically connecting the first lead frame 16 and one electrode (not shown) on the bottom surface of the LED chip 12. .
The rear end portion 16b of the first lead frame 16 passes through the frame body 14 and is taken out in the horizontal direction.

Further, the tip end portion 18a of the second lead frame 18 exposed in the frame body 14 and the other electrode (not shown) on the upper surface of the LED chip 12 are electrically connected via a bonding wire 20. Become.
The rear end portion 18b of the second lead frame 18 penetrates the frame body 14 and is taken out in the horizontal direction.
Note that the distal end portion 16a of the first lead frame 16 and the distal end portion 18a of the second lead frame 18 are insulated from each other by being disposed facing each other with a predetermined gap in the vertical direction.

  A first step portion 22 is formed on the frame body 14, and a sheet-like non-woven fabric 26 is placed on the first step portion 22 as an aggregate of fibers carrying a phosphor 24. Has been. As a result, the nonwoven fabric 26 carrying the phosphor 24 is disposed above the LED chip 12.

As shown in FIGS. 2 to 5, the nonwoven fabric 26 is formed by intertwining a large number of fibers 28, and a large number of voids 30 (see FIG. 4) are formed between the fibers 28. Since many fibers 28 are entangled three-dimensionally, the surface area of the fibers 28 per unit volume is extremely large.
The total surface area of the fibers 28 constituting the nonwoven fabric 26 can be increased or decreased by several to several hundred times by appropriately adjusting the fiber density of the fibers 28, the thickness of the nonwoven fabric 26, the basis weight, and the like.

The nonwoven fabric 26 is impregnated with a translucent liquid binder in which the phosphor 24 is dispersed and added, and then cured, whereby the phosphor 24 is bonded to the surface of the fibers 28 constituting the nonwoven fabric 26 via the binder 32. At the same time, the gaps 30 between the fibers 28 are filled with the binder 32 to which the phosphor 24 is added.
3 and 4, the amount of the phosphor 24 deposited on the surface of the fiber 28 is larger than the amount of the phosphor 24 in the binder 32 filled in the gap 30. Furthermore, in the distribution state of the phosphors 24 in the binder 32 filled in the gaps 30, the amount of the phosphors 24 increases as the fibers 28 are approached.

As the translucent binder 32, for example, various organic materials such as silicone resin, epoxy resin, and acrylic resin, and various inorganic materials such as sol-gel glass and water glass can be used.
The fibers 28 are made of resin fibers such as nylon, polyester, acrylic, and polypropylene, cellulose-based chemical fibers such as rayon, and short fibers such as glass fibers, alumina fibers, and metal fibers, and the diameter is 1 to 20 μm and the length. Is about 0.5 to 20 mm, but it is of course possible to use fibers 28 made of long fibers having a length of about 50 to 100 mm.
From the viewpoint of light transmittance, it is preferable that the fiber 28 is made of a light transmissive material.

When the phosphor 24 is irradiated with light such as ultraviolet rays or blue visible light emitted from the LED chip 12, the phosphor 24 converts the wavelength of the light into light such as visible light having a predetermined wavelength. Can be used.
As a phosphor 24 for red light emission that converts ultraviolet light into red visible light, M ₂ O ₂ S: Eu (M is one of La, Gd, and Y), 0.5 MgF ₂ .3.5MgO.GeO ₂ : _{Mn, 2MgO · 2LiO 2 · Sb} 2 O 3: Mn, Y (P, V) O 4: Eu, YVO 4: Eu, (Sr, Mg) 3 (PO 4): Sn, Y 2 O 3: Eu, CaSiO ₃ : Pb, Mn, etc.
Further, as a phosphor 24 for green light emission that converts ultraviolet light into green visible light, BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn, Zn ₂ SiO ₄ : Mn, (Ce, Tb, Mn) MgAl ₁₁ O ₁₉ , LaPO ₄ : Ce, Tb, (Ce, Tb) MgAl ₁₁ O ₁₉ , Y ₂ SiO ₅ : Ce, Tb, ZnS: Cu, Al, ZnS: Cu, Au, Al, (Zn, Cd) S: Cu, Al, SrAl ₂ O ₄ : Eu, SrAl ₂ O ₄ : Eu, Dy, Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy, Y ₃ Al ₅ O ₁₂ : Tb, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, Y ₃ Al ₅ O ₁₂ : Ce, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, and the like.
Furthermore, as a phosphor 24 for blue light emission that converts ultraviolet light into blue visible light, (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, BaMg ₂ Al ₁₆ O ₂₇ : Eu, (Sr, Mg) ₂ P ₂ O ₇ : Eu, Sr ₂ P ₂ O ₇ : Eu, Sr ₂ P ₂ O ₇ : Sn, Sr ₅ (PO ₄ ) ₃ Cl: Eu, BaMg ₂ Al ₁₆ O ₂₇ : Eu, CaWO ₄ , CaWO ₄ : Pb, ZnS: Ag, Cl, ZnS: Ag, Al, (Sr, Ca, Mg) 10 (PO 4) 6 Cl 2: there is Eu and the like.
Further, in the case of obtaining white light using the LED chip 12 that emits blue visible light as a light source, etc., as a phosphor 24 for green light emission that converts blue visible light emitted from the LED chip 12 into green visible light, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, SrGa ₂ S ₄ : Eu, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, α-SiAlON: Eu, β-SiAlON: Eu, and the like.
Further, when the LED chip 12 that emits blue visible light is used as a light source, the phosphor 24 for red light emission that converts the blue visible light emitted from the LED chip 12 into red visible light is (Sr, Ca ) S: Eu, (Ca, Sr) ₂ Si ₅ N ₈ : Eu, CaSiN ₂ : Eu, CaAlSiN ₃ : Eu, and the like.
Various colors can be generated by appropriately selecting and mixing the phosphor 24 for red light emission, the phosphor 24 for green light emission, and the phosphor 24 for blue light emission.
The phosphor 24 includes organic and inorganic fluorescent dyes and organic and inorganic fluorescent pigments.

  Thus, in the LED 10 of the present invention, a large number of fibers 28 are entangled three-dimensionally, and the phosphor 24 is supported on the nonwoven fabric 26 having a very large surface area of the fibers 28 per unit volume. A large carrying amount and surface area of the phosphor 24 per unit volume can be secured.

A second step portion 34 is formed above the first step portion 22 of the frame body 14, and a light-transmitting bottomed cylindrical body 36 made of resin or the like is formed on the second step portion 34. The bottomed cylindrical body 36 is filled with a cylindrical translucent elastic body 38 made of silicon rubber.
A plurality of protrusions 40 are formed in the vertical direction of the outer surface of the bottomed cylindrical body 36 to engage with protrusions 44 of the lid portion 42 described later.

In FIG. 1, reference numeral 42 denotes a dome-shaped cylindrical lid portion made of resin or the like and having translucency. A plurality of protrusions 44 to be engaged are formed.
Further, the inner diameter of the lid portion 42 is slightly smaller than the outer shape of the bottomed cylindrical body 36, and the projection 44 on the inner surface of the lid portion 42 is engaged with the projection 40 on the outer surface of the bottomed cylindrical body 36. Thus, the upper end opening of the bottomed cylindrical body 36 is closed.
Note that a plurality of protrusions 44 on the inner surface of the lid portion 42 and protrusions 40 on the outer surface of the bottomed cylindrical body 36 are formed in the vertical direction. By changing the alignment position, the lid 42 can be moved in the vertical direction.

Further, a translucent dome-shaped member 48 (see FIGS. 6 to 8) having a spherical outer surface 46 facing the translucent elastic body 38 is disposed above the translucent elastic body 38.
FIG. 1 shows a state in which the dome-shaped member 48 is disposed between the lid 42 and the translucent elastic body 38 without the translucent elastic body 38 being deformed. When the engagement position of the projection 44 of the lid portion 42 and the projection 40 of the bottomed cylindrical body 36 is changed and the lid portion 42 is moved downward, the dome-shaped member 48 is also moved downward, As a result, when the spherical outer surface 46 of the dome-shaped member 48 contacts and presses the translucent elastic body 38, the translucent elastic body 38 is elastically deformed into a concave shape to form a concave lens.
That is, the dome-shaped member 48 can be moved in the vertical direction by moving the lid portion 42 in the vertical direction. Then, by moving the dome-shaped member 48 in the vertical direction, the spherical outer surface 46 of the dome-shaped member 48 contacts and presses the translucent elastic body 38, and the translucent elastic body 38 is elastically deformed to form a concave lens. In addition, the contact area of the spherical outer surface 46 that contacts and presses the translucent elastic body 38 can be changed.

  Thus, by changing the contact area of the spherical outer surface 46 that contacts and presses the translucent elastic body 38, the region of the translucent elastic body 38 that is formed into a concave lens changes. That is, if the contact area of the spherical outer surface 46 that contacts and presses the translucent elastic body 38 is increased, the area of the translucent elastic body 38 that becomes a concave lens also increases, while the translucent elastic body 38 is contact-pressed. If the contact area of the spherical outer surface 46 is reduced, the area of the translucent elastic body 38 to be a concave lens is reduced.

  When a voltage is applied to the LED chip 12 via the first lead frame 16 and the second lead frame 18, the LED 10 emits light having a wavelength that excites the phosphor 24 from the LED chip 12. This light is converted into light such as visible light having a predetermined wavelength by the phosphor 24 carried on the nonwoven fabric 26 arranged on the LED chip 12, and the bottomed cylindrical body 36 → the translucent elastic body 38 → the dome shape The member 48 is radiated to the outside through the lid 42.

  In the LED 10 of the present invention, a translucent elastic body 38 is disposed above the LED chip 12, and a spherical outer surface 46 facing the translucent elastic body 38 above the translucent elastic body 38. A translucent dome-shaped member 48 is disposed, and by moving the dome-shaped member 48 in the vertical direction, the spherical outer surface 46 of the dome-shaped member 48 contacts and presses the translucent elastic body 38; The translucent elastic body 38 is elastically deformed into a concave shape to form a concave lens, and the contact area of the spherical outer surface 46 that contacts and presses the translucent elastic body 38 is changed. By changing the above, and changing the concave lens area of the translucent elastic body 38, the irradiation range of the light emitted from the LED chip 12 can be changed.

That is, as shown in FIG. 10, when the dome-shaped member 48 is disposed above the translucent elastic body 38 without making the translucent elastic body 38 into a concave lens, the light emitted from the LED chip 12 is In this case, the light irradiation range is the narrowest.
On the other hand, as shown in FIG. 11, when the spherical outer surface 46 of the dome-shaped member 48 is pressed against the translucent elastic body 38, and the translucent elastic body 38 is elastically deformed to form a concave lens, an LED chip is used. The light emitted from 12 diffuses by passing through the concave lens region, and the light irradiation range can be widened.

  In the LED 10 of the present invention, a large number of fibers 28 are three-dimensionally entangled between the LED chip 12 and the translucent elastic body 38, and the surface area of the fibers 28 per unit volume is extremely large. Since the non-woven fabric 26 is disposed and the phosphor 24 is supported on the non-woven fabric 26, a large amount and surface area of the phosphor 24 can be secured per unit volume, and a high-brightness LED 10 can be realized.

  In the above description, the case where the nonwoven fabric 26 is used as an assembly of fibers has been described as an example. However, the present invention is not limited to this, and a woven fabric formed by weaving a large number of fibers is used. The phosphor 24 may be supported on the fibers constituting the woven fabric. Although this woven fabric also does not reach the non-woven fabric 26, since the surface area of the fiber per unit volume is large, it is possible to ensure a large carrying amount and surface area of the phosphor 24 per unit volume, and the high-brightness LED 10 Obtainable.

It is a schematic sectional drawing which shows typically the light emitting diode which concerns on this invention. It is a perspective view which shows typically the sheet-like nonwoven fabric which carry | supported fluorescent substance. It is the elements on larger scale which show typically the sheet-like nonwoven fabric which carry | supported fluorescent substance. It is an enlarged view which shows typically the fiber which comprises the sheet-like nonwoven fabric which carry | supported fluorescent substance. It is sectional drawing which shows typically the fiber which comprises the sheet-like nonwoven fabric which carry | supported fluorescent substance. It is sectional drawing which shows the translucent dome-shaped member which has a spherical outer surface. It is a bottom view which shows the translucent dome-shaped member which has a spherical outer surface. It is a top view which shows the translucent dome-shaped member which has a spherical outer surface. It is a schematic sectional drawing which shows the state which elastically deformed the translucent elastic body with the dome-shaped member. It is explanatory drawing which shows the irradiation range of the light in case a translucent elastic body is undeformed. It is explanatory drawing which shows the irradiation range of the light at the time of making a translucent elastic body elastically deform with a dome-shaped member. It is a schematic sectional drawing which shows the conventional light emitting diode typically.

10 Light emitting diode
12 LED chip
14 Frame
16 First lead frame
18 Second lead frame
20 Bonding wire
22 First step of the frame
24 phosphor
26 Nonwoven fabric
28 fibers
30 Air gap
32 binder
34 Second step of frame
36 Bottomed cylinder
38 Translucent elastic body
40 Protrusion of bottomed cylinder
42 Lid
44 Lid projection
46 Spherical outer surface
48 Dome-shaped member

Claims (4)

LED chip, translucent elastic body disposed above LED chip, translucent dome shape having spherical outer surface disposed above translucent elastic body and opposed to translucent elastic body A light emitting diode comprising a member,
By moving the dome-shaped member in the vertical direction, the spherical outer surface of the dome-shaped member contacts and presses the translucent elastic body, and the translucent elastic body is elastically deformed into a concave shape to form a concave lens. A light emitting diode characterized in that the contact area of a spherical outer surface that contacts and presses the elastic elastic body is changed.   The light-emitting diode according to claim 1, wherein the translucent elastic body is made of silicon rubber.   A phosphor that arranges a fiber assembly between the LED chip and the translucent elastic body, and converts the light emitted from the LED chip into light of a predetermined wavelength and emits the fiber aggregate to the fiber assembly. The light emitting diode according to claim 1, wherein the light emitting diode is supported.   4. The light emitting diode according to claim 3, wherein the aggregate of fibers is a nonwoven fabric, and a phosphor is supported on the fibers constituting the nonwoven fabric.

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