JP6597809B2 - Light source device - Google Patents

Description

  The present invention relates to a wavelength conversion member and a light source device.

As a light source device in which a semiconductor laser element and a phosphor-containing member are combined, there is a device that irradiates a laser beam on a substrate having a phosphor-containing member on a substrate to obtain, for example, white reflected light (
Patent Document 1).

JP 2012-243624 A

In such a light source device, in order to improve the strength of the phosphor-containing member, the phosphor-containing member itself may be thickened. In addition, the phosphor generates heat due to laser light irradiation. In order to dissipate this heat, the area of the surface of the phosphor-containing member on the substrate side may be increased.
On the other hand, when using a thick and large area phosphor-containing member to improve strength and heat dissipation,
Laser light is likely to spread in it, and the luminance is lowered.

An object of this invention is to provide the wavelength conversion member which can improve a brightness | luminance while improving intensity | strength and heat dissipation, and a light source device using the same.

The present application includes the following inventions.
(1) A light reflecting member that reflects laser light and a phosphor-containing layer provided on the light reflecting member,
The phosphor-containing layer has one or more protrusions irradiated with laser light,
The wavelength conversion member, wherein the convex portion is larger than a spot of laser light irradiated on the convex portion.
(2) the wavelength conversion member described above;
One or more laser elements for irradiating the phosphor-containing layer with laser light,
The said wavelength conversion member is a light source device arrange | positioned in the position where the laser beam irradiated from the said laser element is irradiated to the said convex part.

ADVANTAGE OF THE INVENTION According to this invention, the wavelength conversion member which can improve a brightness | luminance while improving intensity | strength and heat dissipation, and a light source device using the same can be provided.

It is a top view of the wavelength conversion member concerning a 1st embodiment. It is A-A 'line sectional drawing of FIG. 1A. It is a top view of the wavelength conversion member concerning a 2nd embodiment. It is A-A 'line sectional drawing of FIG. 2A. It is a top view of the wavelength conversion member concerning a 3rd embodiment. It is a top view of the wavelength conversion member concerning a 4th embodiment. It is sectional drawing of the wavelength conversion member which concerns on 5th Embodiment. It is sectional drawing of the wavelength conversion member which concerns on 6th Embodiment. It is sectional drawing of the wavelength conversion member which concerns on 7th Embodiment. It is a schematic diagram for demonstrating the structure of the light source device which concerns on 8th Embodiment.

Hereinafter, the wavelength conversion member and the light source device according to the present embodiment will be described with reference to the drawings.

(Wavelength conversion member)
As shown in FIGS. 1A and 1B, the wavelength conversion member of one embodiment includes a light reflection member for reflecting laser light and a phosphor-containing layer provided on the light reflection member. The light reflecting member is provided on the substrate.
The phosphor-containing layer has one or more convex portions that are irradiated with laser light. Specifically, the phosphor-containing layer has a base portion and a convex portion continuous with the base portion from the substrate side. A convex part is larger than the spot of the laser beam irradiated to a convex part.
Thereby, since a base part larger than a convex part can be fixed to a substrate or the like, the strength can be improved, and since such a base part can be used as a heat dissipation path to the substrate or the like, The heat dissipation can be improved. In addition, since the convex portion can suppress the spread of the laser light irradiated to the convex portion inside the phosphor-containing layer, the luminance of the light emitting device that irradiates the wavelength conversion member with the laser light can be improved. .

(substrate)
The substrate is a member to which the phosphor-containing layer is fixed via a light reflecting member. Various materials such as conductivity and insulation can be used for the substrate. For example, the material of the substrate includes metal, ceramics, glass, or a combination thereof. Examples of metals include Ag and C.
u, Al, Au, Rh, or an alloy containing one or more of these, and the ceramic is, for example, alumina. The substrate may be either a single layer or a laminated structure of these materials.
The substrate is preferably formed of a material having a higher thermal conductivity than the phosphor-containing layer described later. Thereby, the heat | fever of a fluorescent substance content layer can be thermally radiated efficiently. Examples of such a material include aluminum, an aluminum alloy, copper, and a copper alloy.
The phosphor-containing layer is typically fixed to the substrate via a light reflecting member and a bonding layer so that a heat dissipation path from the phosphor-containing layer to the substrate is secured. Each member may not be in direct contact, and an adhesion layer, a barrier layer, or the like can be provided between the members. In top view,
The area of the substrate is preferably larger than the area of the phosphor-containing layer. Thereby, almost the entire surface of the phosphor-containing layer can be fixed to the substrate via the light reflecting member or the like, so that it can be firmly fixed and heat can be efficiently radiated. The top view or the plan view is
This refers to the case when viewed from a direction substantially perpendicular to the main surface of the substrate.
The substrate has only to have a thickness that can ensure a desired strength. For example, the thickness is about 500 μm or more. Moreover, the thickness of a board | substrate shall be 5 mm or less, for example. Usually, the substrate is thicker than the phosphor-containing layer.

(Light reflecting member)
The light reflecting member is preferably capable of reflecting the irradiated laser beam at least in a region facing the phosphor-containing layer. For example, a film-like light reflecting member is formed on one main surface side (lower surface side) of the phosphor-containing layer. What is necessary is just to arrange | position a board | substrate on the opposite side to the fluorescent substance content layer of a light reflection member. The light reflecting member only needs to be disposed at least directly below the convex portion of the phosphor-containing layer,
It is preferably provided on almost the entire lower surface of the phosphor-containing layer. The light reflecting member preferably has a reflectance of 60% or more, more preferably 90% or more, with respect to the irradiated laser beam. The light reflecting member preferably has a reflectance of 60% or more, and more preferably 90% or more, of the phosphor with respect to wavelength-converted light. In order to obtain a relatively high reflectance in a wide wavelength band, the light reflecting member preferably includes a metal layer. For example, the light reflecting member includes an Ag layer or an Al layer. The thickness of the light reflecting member is preferably thick enough to obtain the above-described reflectance, for example, 100 nm or more. The thickness of the light reflecting member can be set to 3 μm or less, for example.

When the metal layer is directly provided on the phosphor-containing layer, a part of light is absorbed by the metal layer. Therefore, it is preferable to have a translucent film made of a dielectric between the metal layer and the phosphor-containing layer. In this case, the light from the phosphor-containing layer is first reflected at the interface due to the refractive index difference between the phosphor-containing layer and the translucent film, and the light not reflected there is reflected by the metal film. . In this way, the translucent film made of a dielectric material hardly absorbs light, so that the reflectance can be improved as a whole. The translucent film may be a single-layer dielectric film or a dielectric multilayer film. Examples of the material for the translucent film include SiO ₂ and materials having better thermal conductivity than phosphors, such as Al ₂ O ₃ and MgO. When the translucent film is a dielectric multilayer film, for example, S
A multilayer film in which an iO ₂ film and an Nb ₂ O ₅ film are repeatedly stacked can be formed.

(Phosphor-containing layer)
The phosphor-containing layer is a layer used for wavelength conversion of laser light emitted from the laser element. Therefore, a phosphor that can convert the wavelength of laser light emitted from the laser element is included. Examples of the phosphor include a YAG phosphor, a LAG phosphor, and a TAG phosphor. Two or more kinds of phosphors may be included in one phosphor-containing layer 12. In particular, when a laser element whose active layer is made of a GaN-based material is used, a YAG-based phosphor is preferable.
This is because the durability against laser light is high and white light can be obtained in combination with a blue laser.

The phosphor-containing layer may be formed only of the phosphor, but is preferably formed of the phosphor and a holding body for holding the phosphor. In the former case, the uneven distribution of the phosphor can be reduced. On the other hand, in the latter case, the holding body is preferably an inorganic material. Thereby, deterioration, discoloration, etc. of the holding body due to light emitted from the laser element can be suppressed. Examples of the inorganic material include Al ₂ O ₃ and Y ₂ O ₃ .

The phosphor-containing layer has a base portion and a convex portion continuous with the base portion from the light reflecting member side. The convex portion only has to protrude upward from the base portion, that is, in a direction away from the light reflecting member. A convex part is larger than the spot of the laser beam irradiated to a fluorescent substance content layer. That is, when viewed from the upper surface side, the outer edge of the convex portion is larger than the laser beam spot. As a result, the laser beam is
Even when diffused and spread in the phosphor-containing layer, the spread can be limited at the convex portion, so that the luminance can be improved. In addition, the light generated when the phosphor is excited by the laser light can be limited in the convex portion, so that the luminance can be improved. In particular, the light generated in the phosphor has almost no directivity and is likely to spread in all directions in the vertical and horizontal directions inside the phosphor-containing layer. In addition, the restriction | limiting of the spread of the light by a convex part can be performed by reflecting a part of light by the refractive index difference of a convex part and the outer side (for example, air | atmosphere), for example. By limiting the spread of light in this way, the convex portion can be made to emit the strongest light in the phosphor-containing layer when observed from above during irradiation with the laser beam.
It is preferable that the area of the convex portion in the top view is large enough to completely include the spot of the irradiated laser beam and small enough to obtain a desired luminance. For example, the area of the convex part in the top view is preferably not more than twice the spot area of the laser beam. That is, the area of the convex portion is preferably about 100% to 200% of the area of the laser beam spot, and 110% to 15%.
About 0% is preferable. Note that the unit of luminance is cd / m ² , and the luminance is the luminous intensity per unit area. Therefore, the luminance decreases as the area of the convex portion increases and the light emitting surface increases. In order to avoid this, specifically, the area of the convex portion is preferably 1 mm ² or less, and more preferably 0.5 mm ² or less. By setting the size of the convex portion in such a range, the advantage of the laser diode having higher luminance than the LED can be further utilized. Moreover, the area of a convex part is 0.01 mm < ² > or more, for example, and 0.25 mm < ² > or more may be sufficient as it. In addition, the spot of a laser beam refers to the shape when a laser beam reaches | attains the surface of a convex part. The far-field image (FFP) of the laser beam has a substantially elliptical shape. For example, if the laser beam is irradiated from the direction intersecting the main surface of the substrate as will be described later, the spot of the laser beam has a deformed ellipse shape. It becomes.

Examples of the shape of the projection in plan view include various shapes such as a substantially polygonal shape, a substantially circular shape, and a substantially elliptical shape. From the viewpoint of ease of manufacture, a substantially polygonal shape such as a triangle or a quadrangle is advantageous. On the other hand, if the shape is close to the spot of the laser beam, the size of the convex portion can be made closer to the size of the spot of the laser beam, so that the luminance can be further improved. Examples of such a shape include a substantially circular shape and a substantially elliptical shape.
The convex portion has a top surface, that is, a surface on the laser beam irradiation side. The top surface may be a curved surface (dome shape or bowl shape), but is preferably a substantially flat surface. In this case, the convex part also has a side surface extending in the direction from the top surface toward the light reflecting member. Such a convex part can be formed more easily than a convex part consisting of a curved surface.

The substantially flat surface may be flat when viewed macroscopically, and may be a rough surface.
Since such a rough surface can diffusely reflect the laser light, it is considered that the wavelength-converted light and the laser light can be mixed more efficiently. A light source device capable of obtaining such mixed light is advantageous as a light source for applications that require high color rendering properties to some extent, such as for vehicle headlights.

In another embodiment, a function of suppressing reflection of laser light may be added to the surface of the phosphor-containing layer, particularly to the top surface of the convex portion. For example, an antireflection film may be provided on the top surface of the convex portion. Further, in the wavelength range of the laser light, a film having a function of mainly transmitting at the angle where the laser light is incident on the phosphor-containing layer and reflecting mainly at the other angle may be provided on the top surface of the convex portion. Good. The film functions as a transmission film for the wavelength-converted light of the phosphor. Thereby, only the wavelength-converted light can be substantially extracted from the phosphor-containing layer, which is advantageous for use as a light source for a projector, for example.

Moreover, when the top surface of a convex part is a substantially polygon, it is preferable that the area of a top surface is larger than the area of each side surface (surface extended toward a light reflection member from a top surface) of a convex part. Thereby, the top surface of a convex part can be made into the main light emission surface of a wavelength conversion member. The top surface of the convex portion is, for example, a surface substantially parallel to the main surface of the light reflecting member.
Only one convex portion may be arranged with respect to the base portion. In this case, it is preferable that the convex portion is disposed at substantially the center of the base portion. Thereby, since the heat generated in the convex portion can be spread from the substantially center of the base portion, the heat can be efficiently radiated.
Further, the convex portion may be partitioned by a groove (for example, 12c in FIGS. 1A and 1B). That is, the surface of the phosphor-containing layer may be partitioned by the grooves. In this case, the bottom surface of the groove corresponds to the surface of the base portion. Further, a plurality of convex portions may be arranged with a groove interposed therebetween. When a plurality of convex portions are arranged, at least one convex portion 12a only needs to have the size described above. Such convex portions 12a are irradiated with laser light. The other protrusions 12a ′ that are not irradiated with laser light may be the same as or different from the shape and size of at least one protrusion 12a having the above-described size. In addition, since a structure with such convex part 12a 'can be produced if a groove is formed by a dicing apparatus or the like, it can be easily manufactured.

The groove only needs to have a depth of, for example, 30% or more of the thickness of the phosphor-containing layer, preferably 50% or more, and more preferably about 50 to 80%. By setting it as this range, a fluorescent substance content layer cannot be separated easily and integration can be maintained. Specifically, the depth of the groove is, for example, about 60 μm or less. However, the bottom of the groove is preferably disposed at a distance of 20 μm or more in the thickness direction from the surface of the phosphor-containing layer on the light reflecting member side, and may be disposed at a distance of 40 μm or more. Thereby, isolation | separation in the groove | channel of a fluorescent substance content layer can be suppressed. The depth of the groove can be restated as the height of the convex portion. A reflective film may be provided in the groove. For example, after forming the groove, a reflective film is formed on almost the entire exposed surface of the phosphor-containing layer, and then the reflective film is removed from the upper surface of the convex portion by polishing or the like from the upper surface side of the convex portion. A structure in which a reflective film is formed in the groove can be obtained. Since the bottom of the groove does not reach the surface of the phosphor-containing layer on the light reflecting member side, the bonding area with the substrate is large as compared with the case where the groove is reached. For this reason, it is possible to reduce the possibility of the protrusions being scattered or damaged when a load is applied to the phosphor-containing layer by polishing or the like. As the reflective film, a dielectric multilayer film, a single-layer or multilayer metal film, or the like can be used. Niobium oxide or the like can be used as the dielectric, and Al or the like can be used as the metal. The reflective film is atomic layer D
(eposition: ALD) method may be used. Further, a light absorbing material that absorbs light may be disposed in the groove, or both a light reflecting material and a light absorbing material may be disposed.

It is preferable that the groove has a width larger than the wavelength of the laser light irradiated on the phosphor-containing layer. Thereby, even when the laser light diffuses and spreads in the phosphor-containing layer, the spread is easily divided by the grooves. Therefore, it is possible to suppress a decrease in luminance when the wavelength conversion member is caused to emit light. Furthermore, the width of the groove is preferably larger than the wavelength of the light emitted from the phosphor contained in the phosphor-containing layer, that is, the light emitted when the phosphor is excited by laser light. Thereby, the spread of the wavelength-converted light by the phosphor can be easily divided by the groove, and the reduction in luminance can be further suppressed. In this way, by setting the width of the groove to be equal to or greater than the wavelength of the light to be confined in the convex portion, the light is blocked at these interfaces due to the refractive index difference between the convex portion and the one filled in the groove (typically the atmosphere). Can be reflected. The width of the groove is, for example, 3 mm or less.
The width of the groove is, for example, 0.1 mm so that it can be easily processed when formed using a blade or the like.
That's it. Furthermore, it is good also as 0.4 mm or more. The width of the groove means the main surface of the light reflecting member (surface on the phosphor-containing layer side) of the distance from one side surface of the groove to the other side surface in a direction substantially perpendicular to the extending direction of the groove. And the distance in a direction substantially parallel to. For example, the width of the uppermost portion of the groove is set within the above range. More preferably, when the groove is cut in a direction substantially perpendicular to the extending direction of the groove, the groove is formed so that the width of the groove is within the above-described range in a region more than half of the depth direction of the groove. To do.
In addition, although it is preferable that all the groove | channels are the same depth and / or width | variety, the convex part 12 mentioned above is mentioned.
As long as the groove that defines a has the above-described width and depth, the groove that defines the convex portion 12a ′ other than the above-described convex portion 12a has the above-described width and / or depth. Also good.

The cross-sectional shape of the groove may be, for example, a quadrangle (for example, 12c in FIG. 1A), a semi-elliptical shape or a semi-circular shape (for example, 72c in FIG. 7), and narrow at the bottom side. (For example, 62c in FIG. 6) or V-shape (for example, FIG. 5).
52c). In any of these cross-sectional shapes, the maximum width and maximum depth of the grooves may correspond to the above-described width and depth.
2A and 2B, when there is only one protrusion 22a, the base 2
The region exposed from the convex portion 22a in 2b can have the same shape as the above-described groove.

As the thickness of the phosphor-containing layer becomes thinner, the phosphor-containing layer becomes more easily broken and becomes difficult to handle. On the other hand, if the film thickness is too thick, the distance from the vicinity of the top surface of the convex portion, which is the main heat generation area, to the substrate becomes long, and the heat dissipation is deteriorated. Therefore, the thickness of the phosphor-containing layer is preferably 50 μm to 300 μm, more preferably 80 μm to 200 μm, as the total thickness of the convex portion and the base portion.

The phosphor-containing layer can be formed using, for example, discharge plasma sintering (SPS), hot isostatic pressing (HIP), cold isostatic pressing (CIP), or the like.
The groove can be formed by, for example, a dicing or machining center.
The groove may be formed by patterning using a photolithography and etching process, a lift-off method, or the like. Especially, it is preferable to form a groove | channel with the dicing apparatus using a blade or a laser. Thereby, a groove | channel can be formed easily. For example, a blade or a laser may be scanned vertically and horizontally with respect to the phosphor-containing layer. In this case, seeing from the top side
The groove may reach the end of the phosphor-containing layer. The groove may be formed after the phosphor-containing layer is fixed to the substrate. In this way, it is considered that the separation of the phosphor-containing layer by the grooves can be more easily suppressed.

[Light emitting device]
As shown in FIG. 8, the light emitting device 100 according to one embodiment includes one or more laser elements 80 for irradiating the phosphor-containing layer 12 with laser light. The wavelength conversion member 10 is disposed at a position where the laser beam A irradiated from the laser element 80 is irradiated to the convex portion 12 a of the wavelength conversion member 10.
With such a configuration, by securing the area of the phosphor-containing layer in the base portion, the strength and heat dissipation of the phosphor-containing layer can be improved, and the laser inside the phosphor-containing layer is formed by the convex portion. The spread of light or the like can be suppressed. As a result, since the light emitting surface can be mainly limited to the convex portion, the luminance of the light source device can be improved.

In this light emitting device, a wavelength conversion member having one convex portion may be used for one laser element, or a wavelength conversion member having a plurality of convex portions may be used. Moreover, the wavelength conversion member which has one convex part may be used with respect to a several laser element, and the wavelength conversion member which has a several convex part may be used. In the case of using a plurality of laser elements, for example, a plurality of laser beams emitted from the plurality of laser elements are condensed and used as one beam.

(Laser element)
The laser element is used as a light source of the light source device. Since the laser light emitted from the laser element is light having high directivity, the brightness is generally higher than that of the light emitted from the light emitting diode (LED). Therefore, by using a laser element as a light source, it is possible to realize a light source device with higher brightness than when using an LED.

Laser light A emitted from the laser element travels toward the wavelength conversion member in the atmosphere or via an optical member or the like. A part of the laser light A irradiated to the convex portion of the phosphor-containing layer is taken into the phosphor-containing layer. At this time, a part of the laser light A may be reflected on the surface depending on the surface state of the phosphor-containing layer. For example, the surface state of the phosphor-containing layer is adjusted so that more light is incident on the phosphor-containing layer than the reflected light. The light taken into the phosphor-containing layer becomes light whose wavelength has been converted by partially exciting the phosphor. The other part is reflected by the light reflecting member, the wavelength is not converted during that time, and the laser light A may be extracted outside while maintaining the wavelength. The light B extracted outside may be only the wavelength-converted light, or may be a mixed light of the laser light A and the wavelength-converted light. Laser light A
Is scattered by the phosphor-containing layer, and thus may not be laser light after passing through the phosphor-containing layer. However, the light of the wavelength of the laser light A is in the direction of the light B even after passing through the phosphor-containing layer.
That is, when the surface of the convex portion is a reflection surface, the light tends to have maximum intensity in the direction in which the laser light A is reflected. Since the light emitted from the phosphor has almost no directivity, the direction in which the wavelength-converted light travels is not limited to the direction of light B in FIG. The light distribution of the wavelength-converted light is considered to depend on the incident angle of the laser light A and the shape of the phosphor-containing layer. For example, if the convex portion has a substantially flat top surface as shown in FIG. 8, it is considered that light is mainly extracted in the upward direction from the top surface. The laser element is provided at a position separated from the phosphor-containing layer. Thereby, since the heat dissipation path from the laser element and the heat dissipation path from the phosphor-containing layer can be made different paths, the heat of each member can be efficiently removed.

In particular, among the laser light, the light taken into the wavelength conversion member is taken into the convex portion of the wavelength conversion member. The spread of is suppressed. As a result, the spread of the laser light taken into the convex portion can be suppressed, and the spread of the light emitted by the phosphor excited by the laser light can be suppressed, so that the light is efficiently guided and extracted in a predetermined direction. be able to. As a result, the light emitting surface when the wavelength conversion member is observed from the outside can be generally limited to the convex portion and its periphery, that is, the area of the light emitting surface can be reduced compared to the case where the convex portion is not formed. it can.
Thereby, the brightness | luminance of a light source device can be improved.

It is preferable that the spot of the laser beam emitted from the laser element has a size that can be accommodated in the above-described convex portion. Specifically, it is preferably 1 mm ² or less, and more preferably 0.5 mm ² or less. The size of the laser beam spot is, for example, 0.007 mm ² or more. The spot size of the laser beam has a width of, for example, 0.1 mm or more. The width refers to the diameter in the case of a substantially circular shape, and refers to the long diameter (the length of the major axis) in the case of a substantially elliptical shape. The spot of the laser beam can be adjusted by using an optical member such as a lens or fiber. The incident angle of the laser light on the wavelength conversion member can be appropriately set depending on the intended light extraction direction, the type of laser light, and the like. For example, a direction perpendicular to the top surface of the convex portion is avoided so that the incident direction of the laser beam does not coincide with the reflection direction.
The laser element is used in a state of being accommodated in a package, for example. It is preferable that the laser element be hermetically sealed by the package, whereby dust collection by the laser light emitted from the laser element can be suppressed.
A plurality of laser elements may be arranged. In this case, it is preferable that the plurality of laser elements are arranged at positions where the laser beams emitted from the laser elements are respectively applied to the same convex portion of the wavelength conversion member. Thereby, it is possible to irradiate high-density laser light with one convex portion, and it is possible to further increase the brightness.
The laser element emits laser light having a peak wavelength in the range of 430 to 470 nm, for example. Laser light in such a wavelength band is suitable for exciting a YAG phosphor. Further, as a laser element that emits laser light of such a wavelength band, a GaN-based laser element can be mentioned.

(Other parts)
In the light emitting device, for example, members such as a light control member, a lens (such as a condensing lens and a collimating lens), a dichroic mirror, and a fiber may be used alone or in combination. Examples thereof include JP2013-250321A and JP2012-243624A. By utilizing such a member, the size and shape of the laser beam spot can be adjusted. Further, the light after passing through the phosphor-containing layer may be condensed using a lens or the like.

Hereinafter, the wavelength conversion member and the light source device according to Embodiments 1 to 8 will be described with reference to the drawings. However, the form shown below is the illustration for materializing the technical idea of this invention, Comprising: This invention is not limited to the following. In addition, the positions, sizes, and the like of members shown in each drawing may be exaggerated for clarity of explanation. About the same name and code | symbol, the same or the same member is shown in principle, and the duplicate description is abbreviate | omitted.

Embodiment 1: Wavelength Conversion Member As shown in FIGS. 1A and 1B, the wavelength conversion member 10 of Embodiment 1 is provided on a light reflection member 13 for reflecting laser light and the light reflection member 13. And a phosphor-containing layer 12. The light reflecting member 13 is provided on the substrate 11.
The phosphor-containing layer 12 includes a base portion 12b and a convex portion 12a continuous with the base portion 12b from the substrate 11 side. The convex part 12a is larger than the spot of the laser beam irradiated to the convex part 12a.

The board | substrate 11 is the structure by which the Ni layer and Au layer were provided in order from the copper plate side on the surface of the copper plate.
The outer shape of the substrate 11 is a plate-like body having a square planar shape, and has a size of about 10 mm × 20 mm and a thickness of about 2 mm.
The phosphor-containing layer 12 is fixed to the central portion of the substrate 11 in plan view. Base part 1
The outer shape of 2b has a quadrangular plan shape, a size of about 3 mm × 3 mm, and a thickness of about 100 μm. That is, the distance from the lower surface of the phosphor-containing layer 12 to the lower end of the groove 12c is 4
It is about 0 μm. The total thickness of the base portion 12b and the convex portion 12a is about 100 μm.
On the surface of the phosphor-containing layer 12, two linear grooves 12c (with a width of about 0.5 mm) are arranged at regular intervals in the vertical and horizontal directions, whereby the central portion of the phosphor-containing layer 12 is defined. Thus, the planar shape is a quadrangular convex portion 12a. Accordingly, a plurality of convex portions 12a ′ are disposed adjacent to the convex portion 12a in a slanted manner in the vertical and horizontal directions through the groove 12c. The depth of the groove 12c is 60 μm
m.
The size of the top surface of the convex portion 12a is smaller than 1 mm ² . Specifically, 0.7 mm x 0.7
It is a square of about mm.
The top surfaces of the convex portions 12a and 12a ′ are flat.
A light reflecting member 13 is provided under the phosphor-containing layer 12, and the light reflecting member 13 is fixed to the substrate 11 by a bonding layer 14. The light reflecting member 13 includes a dielectric multilayer film in which an SiO ₂ film and an Nb ₂ O ₅ film are repeatedly laminated in order from the phosphor-containing layer 12 side, and an Ag layer. The reflectance of the laser beam with respect to the light having a wavelength of 400 to 800 nm of the light reflecting member 13 is 95 to 9.
About 9%.

Thereby, in the base part, the strength of the phosphor-containing layer can be improved, and the strength of the phosphor-containing layer can be supported by the substrate and a heat dissipation path can be secured. Moreover, the spread of the laser beam or the like inside the phosphor-containing layer can be suppressed by the convex portion. As a result, heat dissipation and strength can be improved, and when used with a laser element, the luminance of the light source device can be improved.

Such a wavelength conversion member can be manufactured by the following method, for example.
First, a YAG phosphor [Y _2.95 Ce _0.05 ] Al ₅ O ₁ having an average particle size of about 10 μm.
_A powder made of ₂ and a support made of aluminum oxide (Al ₂ O ₃ ) are mixed and sintered using an SPS sintering method to produce a massive fluorescent member.

Next, the massive fluorescent member is sliced into a plate having a thickness of 0.3 mm with a wire saw. Then, use # 800 diamond abrasive to grind both sides of the plate, polish and CM
P treatment is performed to make the fluorescent member have a thickness of 100 μm. By this step, a plate-like fluorescent member having a mirror surface is obtained.
Thereafter, the fluorescent member is separated into pieces having a size of about 3 mm × 3 mm and bonded to the upper surface of the substrate 11 by the bonding layer 14. The bonding layer 14 mainly includes an AuSn eutectic alloy. Then, the wavelength conversion member 10 provided with the fluorescent substance containing layer 12 is produced by forming the groove | channel 12c.

Embodiment 2: Wavelength Conversion Member As shown in FIGS. 2A and 2B, the wavelength conversion member 20 of Embodiment 2 is provided on a light reflection member 23 for reflecting laser light and the light reflection member 23. And a phosphor-containing layer 22.
The phosphor-containing layer 22 has the same configuration as that of the wavelength conversion member 10 of Embodiment 1 except that the phosphor-containing layer 22 has one convex portion 22a that is continuous with the base portion 22b at the approximate center of the base portion 22b.
Also in this embodiment, the same effect as the wavelength conversion member 10 of Embodiment 1 is acquired. Moreover, since the light emitted from the side surface of the convex portion 22a does not easily enter the phosphor-containing layer 22, light emission in a region other than the convex portion 22a can be suppressed.

Embodiment 3: Wavelength Conversion Member As shown in FIG. 3, the wavelength conversion member 30 of Embodiment 3 includes a light reflecting member for reflecting laser light and a phosphor-containing layer provided on the light reflecting member. 32.
In plan view, the size of the substrate 11 is about 20 mm × 40 mm, and the size of the phosphor-containing layer 32 is about 6 mm × 6 mm. In the phosphor-containing layer 32, the width is 0.5 mm.
The convex portions 32a are arranged in three columns and three rows through the grooves 32c, and are integrally arranged on the base portion 32b at the central portion of the phosphor-containing layer 32, and the convex portions 32a are arranged on the outer periphery thereof through the grooves 32c. It has the same configuration as that of the wavelength conversion member 10 of Embodiment 1 except that 'is arranged so as to be adjacent.
Also in this embodiment, the same effect as the wavelength conversion member 10 of Embodiment 1 is acquired.
Moreover, the convex part 32a is arrange | positioned so that it may respond | correspond to the case where a several different position is irradiated with a laser beam. The laser beam may be applied to each convex portion 32a one by one in a predetermined order.

Embodiment 4: Wavelength Conversion Member As shown in FIG. 4, the wavelength conversion member 40 of Embodiment 4 includes a light reflecting member for reflecting laser light and a phosphor-containing layer provided on the light reflecting member. 42.
The phosphor-containing layer 42 has one convex portion 42a that is continuous with the base portion 42b and has a circular planar shape at the approximate center of the base portion 42b, and a groove 42c is formed on the outer periphery of the convex portion 42a. ,
The wavelength conversion member 1 according to Embodiment 1 except that the convex portion 42a ′ is disposed on the outer periphery of the groove 42c.
It has the same configuration as 0.
Also in this embodiment, the same effect as the wavelength conversion member 10 of Embodiment 1 is acquired. In addition, since the shape of the convex portion in plan view is circular, the approximation with the spot shape of the laser light is Embodiment 1.
Higher than the wavelength conversion member 10. Thereby, the area of the part which is not irradiated with laser light can be reduced, and the luminance can be further improved.

Embodiment 5: Wavelength Conversion Member As shown in FIG. 5, the wavelength conversion member 50 of Embodiment 5 includes a phosphor-containing layer 52 having a convex portion 52a continuous with the base portion 52b at the approximate center of the base portion 52b. Prepare.
Except for the cross-sectional shape of the groove 52c defining the convex portion 52a being V-shaped, it has the same configuration as the wavelength conversion member 10 of the first embodiment.

Embodiment 6: Wavelength Conversion Member As shown in FIG. 6, the wavelength conversion member 60 of Embodiment 6 includes a phosphor-containing layer 62 having a convex portion 62a continuous with the base portion 62b at the approximate center of the base portion 62b. Prepare.
The cross-sectional shape of the groove 62c that partitions the convex portion 62a is a narrow taper shape on the bottom side,
It has the same configuration as the wavelength conversion member 10 of the first embodiment.

Embodiment 7: Wavelength Conversion Member As shown in FIG. 7, the wavelength conversion member 70 of Embodiment 7 includes a phosphor-containing layer 72 having a convex portion 72a that is continuous with the base portion 72b at the approximate center of the base portion 72b. Prepare.
It has the same configuration as the wavelength conversion member 10 of Embodiment 1 except that the cross-sectional shape of the groove 72c that partitions the convex portion 72a is a semi-elliptical shape.

Embodiment 8: Light-Emitting Device As shown in FIG. 8, the light-emitting device 100 of Embodiment 8 includes a wavelength conversion member 10 and one or more laser elements 80 for irradiating the phosphor-containing layer 12 with laser light. . The wavelength conversion member 10 is disposed at a position where the laser beam A irradiated from the laser element 80 is irradiated to the convex portion 12 a of the wavelength conversion member 10.
The laser element 80 can emit laser light having a peak wavelength of about 450 nm, and the FFP of the laser light has a substantially elliptical shape. As shown in FIG. 8, since the laser light is incident on the top surface of the convex portion 12a from an oblique direction, the spot shape of the laser light on the top surface of the convex portion 12a is substantially elliptical. As for the size of the spot, for example, the length in the longitudinal direction is 0.5 mm, and the length in the lateral direction is 0.3 mm.

With such a configuration, it is possible to improve the strength and heat dissipation of the phosphor-containing layer by securing the area of the phosphor-containing layer in the base portion. Further, the base part of the phosphor-containing layer can secure a heat dissipation path to the substrate or the like with a relatively large area, and enables efficient heat dissipation. Furthermore, the spread of the laser beam or the like inside the phosphor-containing layer can be suppressed by the convex portion. As a result, the luminance of the light source device can be improved.

The light source device of the present invention can be used in accordance with various uses such as a projector device, various in-vehicle light sources including a headlight, a backlight light source of a liquid crystal display, and various lighting fixtures.

10, 20, 30, 40, 50, 60, 70 Wavelength conversion member 11 Substrate 12, 22, 32, 42, 52, 62, 72 Phosphor-containing layer 12a, 22a, 32a, 42a, 52a, 62a, 72a Projection 12a ', 32a', 42a 'Convex part 12b, 22b, 32b, 42b, 52b, 62b, 72b Base part 12c, 32c, 42c, 52c, 62c, 72c Groove 13, 23 Light reflecting member 14 Bonding layer 80 Laser element 100 Light emitting device A Laser light B Light

Claims (10)

One or more laser elements that emit laser light;
A light reflecting member capable of reflecting the laser light and a wavelength conversion member having a phosphor-containing layer provided on the light reflecting member,
The phosphor-containing layer, in order from the light reflecting member side, a base portion, protruding from the base portion, anda plurality of convex portions partitioned by the groove,
One or more convex portions of the plurality of convex portions are convex portions irradiated with the laser beam,
The light source device characterized in that the convex portion irradiated with the laser light is larger than the spot of the laser light irradiated on the convex portion irradiated with the laser light. 2. The light source according to claim 1, wherein the convex portion irradiated with the laser light has a substantially flat top surface, and the area of the top surface is smaller than twice the spot area of the laser light. Equipment . 3. The light source device according to claim 1, wherein the convex portion irradiated with the laser light has a substantially flat top surface, and an area of the top surface is 1 mm ² or less. The light source device according to claim 1, wherein the groove has a depth of 50 to 80% of a thickness of the phosphor-containing layer. 5. The light source device according to claim 1, wherein the groove is disposed at a distance of 20 μm or more in a thickness direction from a surface of the phosphor-containing layer on the light reflecting member side. It said groove to a light source device according to claim 1 having a width greater than the wavelength of the irradiated laser light. The light source device according to any one of claims 1 to 6, a substrate is provided below the light reflecting member. The light source device according to claim 7 , wherein the substrate is made of a material having a higher thermal conductivity than the phosphor-containing layer. The light source device according to any one of claims 1 to 8 , wherein the phosphor-containing layer includes a plurality of protrusions irradiated with the laser light . A plurality of the laser elements are arranged, and laser beams emitted from the plurality of laser elements are respectively arranged at positions where the convex portions of the wavelength conversion member irradiated with the same laser lights are irradiated . the light source device according to any one of claims 1 to 9.