JP5661886B2 - Light emitting device, vehicle headlamp and lighting device - Google Patents

Description

  The present invention relates to a light-emitting device that uses fluorescence generated by irradiating a phosphor (light-emitting unit) with laser light as illumination light, a vehicle headlamp including the light-emitting device, and an illumination device.

  In recent years, research on light-emitting devices using semiconductor light-emitting elements such as light-emitting diodes (LEDs) and semiconductor lasers (LDs) as excitation light sources has become active.

  As an example of a technique related to such a light emitting device, there are lamps disclosed in Patent Documents 1 and 2. In the lamps described in Patent Documents 1 and 2, excitation light generated from a single or a plurality of excitation light sources is condensed onto a single small phosphor using a lens.

JP 2005-150041 A (released on June 09, 2005) JP 2004-241142 A (published Aug. 26, 2004)

  However, in the lamps disclosed in Patent Documents 1 and 2, when a semiconductor laser is used as the excitation light source, the laser light is condensed on the light emitting portion using a lens. For example, as shown in FIG. Thus, when the focal point F of the condensing lens L is on the light emitting part, there is a problem that the light density of the laser light at the position of the focal point F may become too high.

  Further, in order to solve such a problem, even if the light emitting unit is arranged by shifting the distance g from the focal point F so as to reduce the light density of the laser light on the light emitting unit (see FIG. 9B), When a deviation or the like occurs in the optical arrangement between the semiconductor laser and the light emitting unit due to vibration or aging deterioration, the light density of the laser light on the light emitting unit easily fluctuates greatly. Further, for example, when the optical arrangement is shifted in the direction in which the focal point F approaches the light emitting unit, the optical density of the laser light on the light emitting unit may eventually become excessively high.

  On the other hand, if the light density of the laser light on the light emitting portion becomes too high, the phosphor particles themselves contained in the light emitting portion or the surrounding sealing material may be damaged (deteriorated) that cannot be recovered by heat or light. Arise.

  Further, even when damage that cannot be restored by heat or light does not occur, the temperature rise due to the heat of the phosphor particles causes a decrease in light emission efficiency (temperature quenching), resulting in a decrease in light emission efficiency of the light emitting portion.

  An object of the present invention is to provide a light emitting device and the like that can prevent deterioration of the light emitting portion and decrease in light emission efficiency due to temperature rise.

  In order to solve the above-described problems, a light-emitting device of the present invention includes a light-emitting unit that generates fluorescence when irradiated with laser light, and a reflecting mirror that has a curved surface that reflects the fluorescence generated from the light-emitting unit on an inner wall. A part of the reflecting mirror is disposed at a position facing the light emitting surface on the opposite side of the light irradiation surface irradiated with the laser light in the light emitting unit, and on the light irradiation surface side Is characterized in that the reflecting mirror surface is not arranged.

  As described above, the light-emitting device according to the present invention includes a light-emitting unit that generates fluorescence when irradiated with laser light, and a reflecting mirror that has a curved surface on the inner wall that reflects the fluorescence generated from the light-emitting unit, In the light emitting part, a part of the reflecting mirror is arranged at a position facing a light emitting surface which is a surface opposite to the light irradiation surface irradiated with the laser light, and the light irradiation surface side has the above-mentioned The reflecting mirror is not arranged.

  Therefore, there is an effect that it is possible to prevent deterioration of the light emitting portion and decrease in light emission efficiency due to temperature rise.

It is sectional drawing which shows schematic structure of the headlamp which is one Embodiment of this invention. It is a schematic diagram for demonstrating the function of a light irradiation part regarding the said headlamp, (a) shows the mode at the time of a normal use state (at the time of a normal state), (b) is by vibration etc. A state when the relative positional relationship between the light emitting unit and the light emitting unit is shifted (in an abnormal state) is shown. It is a figure which shows the structure of the laser element which is other embodiment of this invention, (a) is a perspective view which shows the external appearance of the said laser element, (b) is a structure of the cap part of the said laser element. It is sectional drawing shown. It is a schematic diagram for demonstrating the function of the said laser element. (A) is sectional drawing which shows schematic structure of the headlamp which is further another embodiment of this invention, (b) is a half parabolic which shows an example of the arrangement | positioning method of the said light irradiation part with respect to a half parabolic reflector. It is an upper surface (front side with respect to the paper surface) of the reflecting mirror. (A) is sectional drawing which shows schematic structure of the headlamp which is further another embodiment of this invention, (b) shows another example of the arrangement method of the said light irradiation part with respect to a half parabolic reflector. It is a top view of a half parabolic reflector. It is sectional drawing which shows schematic structure of the headlamp which is further another embodiment of this invention. It is sectional drawing which shows schematic structure of the headlamp which is further another embodiment of this invention. It is a schematic diagram for demonstrating the problem at the time of condensing a laser beam on a light emission part using a lens, (a) shows the mode at the time of a normal use state (at the time of a normal state). (B) shows the state when the relative positional relationship between the light emitting unit and the light emitting unit is shifted due to vibration or the like (in an abnormal state). It is a schematic diagram for demonstrating the problem at the time of condensing a laser beam on a light emission part using a lens, (a) arrange | positions a condensing lens between the said laser element and a light emission part. It is a figure which shows a mode when a laser beam is condensed on the light emission part, and shows a mode that the light emission part is damaged by irradiation of the laser beam in (b) and (a). It is a graph which shows the relationship between a light density and light emission intensity (illuminance).

  An embodiment of the present invention will be described with reference to FIGS. Descriptions of configurations other than those described in the following specific items may be omitted as necessary. However, in the case where they are described in other items, the configurations are the same. For convenience of explanation, members having the same functions as those shown in each item are given the same reference numerals, and the explanation thereof is omitted as appropriate.

[1. Configuration of headlamp 10]
First, a schematic configuration of a headlamp (light emitting device, vehicle headlamp) 10 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view schematically showing the configuration of the headlamp 10. As shown in FIG. 1, the headlamp 10 includes a light irradiation unit (light irradiation unit, laser element) 1, a light emitting unit 4, a half parabolic mirror (reflecting mirror) 5, a window unit 6, and a metal base (heat conducting member) 7. , Fins 8 are provided.

(Light irradiation unit 1)
The light irradiation unit 1 irradiates the light irradiation surface (not shown) of the light emitting unit 4 with laser light whose beam diameter monotonously increases in the propagation direction (laser light). Therefore, according to the light irradiation unit 1, the location where the light density of a laser beam becomes too high on the light irradiation surface of the light emission part 4 does not arise. Thereby, deterioration of the light emission part 4 and the fall of the light emission efficiency by a temperature rise can be prevented. The “light irradiation surface” may be one of a plurality of surfaces constituting the light emitting unit 4 or may be a plurality of surfaces.

  In the headlamp 10 of this embodiment, as shown in FIG. 1, two light irradiation units 1 are provided. However, the number of light irradiation units 1 is not limited to this, and may be only one or three or more. However, it is preferable to provide a plurality of light irradiation units 1. In this case, laser light is oscillated from each of the plurality of light irradiation units 1. In order to obtain high-power laser light, it is easier to use a plurality of light irradiation units 1.

Here, the “beam diameter” is the maximum diameter of the region where the light intensity is 1 / e ² or less of the maximum intensity. Further, “the beam diameter increases monotonously with respect to the propagation direction” means that the increase rate of the beam diameter with respect to the propagation distance of the laser beam is positive or 0 at any position on the optical path. It is not necessary to have a constant value at any position on the optical path.

  Further, the light irradiation unit 1 of the present embodiment includes a laser package (housing) 2 and a magnifying lens (an increase rate changing element, a lens) 3.

(Laser package 2)
The laser package 2 stores and protects a later-described laser chip LC (laser light source), and details thereof will be described later.

  Further, a magnifying lens 3 is mounted on the tip side of the cap portion of the laser package 2, and the laser package 2 and the magnifying lens 3 are integrated. The laser package 2 and the magnifying lens 3 do not necessarily have to be integrated, but if they are integrated, the relative positional relationship between the laser chip LC and the magnifying lens 3 may be reduced due to vibration / aging of the light irradiation unit 1 or the like. There is no deviation. Moreover, the number of parts of the light irradiation unit 1 can be reduced, and the overall size of the light irradiation unit 1 can be reduced.

(Magnifying lens 3)
Here, based on FIG. 10 and FIG. 11, a problem when the laser beam is condensed on the light emitting unit 4 using the condenser lens L will be described. The problems (1) and (2) described below are problems found by the inventors of the present application for the first time, and are problems that have not been pointed out in the prior art including the above-mentioned Patent Documents 1 and 2. .

  (1) First, as shown in FIG. 10A, a condenser lens L is arranged between the light irradiation unit 1 described above and the light emitting unit 4, and the light emitting unit 4 is actually on the light irradiation surface. The relationship between the light density when irradiated with laser light and the state of the light irradiation surface of the light emitting unit 4 was examined.

At this time, it was found that irreparable damage occurred in the light emitting portion 4 in the portion irradiated with the laser light having an optical density of 2000 mW / mm ² or more (however, this characteristic depends on the material of the light emitting portion 4). .

  (2) Next, FIG. 10B shows an example in which the relationship between the light density on the light irradiation surface of the light emitting unit 4 and the light emission intensity (illuminance) is examined.

As shown in FIG. 10B, the emission intensity monotonously increases until the light density on the light irradiation surface of the light emitting unit 4 reaches 800 mW / mm ² , and thereafter, the light density on the light irradiation surface increases. It was found that the emission intensity decreased monotonously as it increased. This is presumably because a decrease in light emission efficiency (temperature quenching) occurs due to a temperature increase due to heat of the phosphor particles contained in the light emitting section 4. This characteristic depends on the material of the light emitting unit 4.

  In consideration of the above problems, the magnifying lens 3 of the present embodiment employs a lens (divergent lens) that can emit laser light while reducing the increase rate of the beam diameter with respect to the propagation direction of the laser light. Accordingly, the laser beam with respect to the light irradiation surface can be reduced by reducing the increase rate of the beam diameter after the emission, in addition to the distance between the laser chip LC and the light emitting unit 4 and the area of the light irradiation surface of the light emitting unit 4. Can be prevented from becoming larger than the area of the light irradiation surface.

  In the present embodiment, the shape of the magnifying lens 3 is a biconvex lens, but is not limited thereto. For example, a biconcave lens, a planoconvex lens, a planoconcave lens, a convex meniscus lens, a concave meniscus lens, and the like can be exemplified.

  Another example of the lens is a GRIN lens (Gradient Index lens).

  The GRIN lens is a lens that produces a lens action due to a refractive index gradient inside the lens even if the lens is not convex or concave.

  Therefore, when the GRIN lens is used, the lens action can be generated while the end surface of the GRIN lens is kept flat.

In addition, it is preferable that the optical density of the laser beam in the arbitrary positions in the light irradiation surface of the light emission part 4 is smaller than 2000 mW / mm < ² >.

As described above, in this example, when the light density of the laser light at an arbitrary position on the light irradiation surface of the light emitting unit 4 is 2000 mW / mm ² or more, it is impossible to restore the portion irradiated with the laser light. Damage (degradation) may occur. Therefore, as in the above configuration, if the light density of the laser light at an arbitrary position on the light irradiation surface of the light emitting unit 4 is smaller than 2000 mW / mm ² , deterioration of the light emitting unit 4 can be reliably prevented.

Further, the optical density of the laser beam at an arbitrary position of the light irradiation surface of the light emitting section 4, 500 mW / mm ² or more, more preferably 1300 mW / mm ² or less.

Light density of the laser beam at an arbitrary position in a light irradiation surface of the light emitting portion 4, or less than 500 mW / mm ^2, exceeds 1300mW / mm ^2, 85% or less when the light emission efficiency of the light emitting portion is maximum There is a possibility of becoming.

Therefore, as in the above-described configuration, the optical density of the laser beam at an arbitrary position in a light irradiation surface of the light emitting portion 4, 500 mW / mm ² or more, if 1300 mW / mm ² or less, deterioration of the light emitting portion and the light emitting portion It is possible to reliably prevent a decrease in light emission efficiency due to the temperature rise.

  The material of the magnifying lens 3 is BK (borosilicate crown) 7, and the lens surface is coated with AR (Anti-Reflection).

  Next, the function of the headlamp 10 (especially the light irradiation unit 1) of this embodiment is demonstrated based on FIG.

  FIG. 2 is a schematic diagram for explaining the function of the headlamp 10 (particularly, the light irradiation unit 1). FIG. 2A shows a state in a normal use state (in a normal state). FIG. 2B shows a state when the relative positional relationship between the light emitting unit and the light emitting unit is shifted due to vibration or the like (in an abnormal state).

  As shown in FIG. 2A, the light irradiation unit 1 has a spot area (irradiation area) of a laser beam incident on the magnifying lens 3 from the laser chip LC more than the area of the light irradiation surface of the light emitting unit 4. small.

  As a result, the laser light after passing through the magnifying lens 3 diverges, and the laser light is irradiated with a wide irradiation area on the light irradiation surface of the light emitting unit 4, so that the laser light is condensed on the light irradiation surface. There is no such a situation that the light density of the laser beam becomes too high.

  Further, even if the normal state in FIG. 2A shifts to the abnormal state in FIG. 2B, the laser light after passing through the magnifying lens 3 is diverged, so There is no possibility that the light density is excessively increased on the surface.

  From the above, it can be seen that the headlamp 10 (particularly the light irradiation unit 1) can prevent the light emitting unit 4 from deteriorating and the light emitting efficiency from being lowered due to temperature rise.

  Instead of the magnifying lens 3, it is also conceivable to irradiate the light emitting unit 4 with laser light (collimated light) collimated with a collimator lens. However, since it is not preferable that the collimated light leaks to the outside even in the unlikely case, it is better to use the laser light while diverging it without using the collimated light as in the light irradiation unit 1 of the present application.

(Light emitting part 4)
The light emitting unit 4 generates fluorescence by receiving laser light emitted from the light irradiation unit 1 and includes a phosphor that emits light by receiving laser light. Specifically, the light emitting unit 4 is one in which a phosphor is dispersed inside a sealing material, or a phosphor is solidified. The light emitting unit 4 can be said to be a wavelength conversion element because it converts laser light into fluorescence.

  In the headlamp 10, the light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

  In the present embodiment, the shape of the light emitting unit 4 is a cylindrical shape (disk shape) having a diameter of the bottom circle of 2 mmφ. However, the size and shape are not limited to this, and any size and various shapes can be used. You can choose. Examples of shapes other than the disc shape include a prismatic shape and an elliptical column shape.

  The light emitting unit 4 is disposed on the metal base 7 and at a substantially focal position of the half parabolic mirror 5. For this reason, the fluorescence emitted from the light emitting unit 4 is reflected on the reflection curved surface (reflection surface) of the half parabolic mirror 5 to control the optical path. An antireflection structure for preventing reflection of laser light may be formed on the upper surface of the light emitting unit 4 (above the paper surface).

  Next, as the phosphor of the light emitting unit 4, for example, an oxynitride phosphor (for example, sialon phosphor) or a III-V compound semiconductor nanoparticle phosphor (for example, indium phosphorus: InP) is used. Can do. These phosphors have high heat resistance against high-power (and / or light density) laser light emitted from the light irradiation unit 1 and are optimal for the headlamp 10. However, the phosphor of the light emitting unit 4 is not limited to the above-described phosphor, and may be another phosphor such as a nitride phosphor.

  In addition, the law stipulates that the illumination light of the headlamp 10 must be white having a predetermined range of chromaticity. For this reason, the light emitting unit 4 includes a phosphor selected so that the illumination light is white.

  For example, when blue, green, and red phosphors are included in the light emitting unit 4 and irradiated with laser light of 405 nm, white light is generated. Alternatively, a yellow phosphor (or green and red phosphor) is included in the light-emitting portion 4, and a so-called blue laser having a peak wavelength in a wavelength range of 450 nm (blue) to 450 nm (blue) or 440 nm to 490 nm. White light can also be obtained by irradiating light.

  The sealing material of the light emitting unit 4 is, for example, a glass material (inorganic glass or organic-inorganic hybrid glass) or a resin material such as silicone resin. Low melting glass may be used as the glass material. The sealing material is preferably highly transparent, and when the laser beam has a high output, a material having high heat resistance is preferable.

(Half parabolic mirror 5)
The half parabolic mirror 5 reflects the fluorescence generated by the light emitting unit 4 on the reflection surface, and forms a light bundle (illumination light) that travels within a predetermined solid angle. The half parabolic mirror 5 may be, for example, a member having a metal thin film formed on the surface thereof or a metal member.

  The opening of the half parabolic mirror 5 (right side with respect to the paper surface) is a semicircle having a radius of 30 mm, and the depth of the half parabolic mirror 5 (width in the left-right direction with respect to the paper surface) is 30 mm. The light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

  The half parabolic mirror 5 is a partial curved surface obtained by cutting a parabolic surface formed by rotating the parabola with the parabolic axis of symmetry as a rotational axis, along a plane including the rotational axis. At least a part of the reflective surface. Thereby, the fluorescence of the light emission part 4 can be efficiently projected within a narrow solid angle, and as a result, the utilization efficiency of the fluorescence can be increased. In addition, a structure other than the parabola can be arranged in a portion corresponding to the other half of the parabola.

  Furthermore, according to the half parabolic mirror 5, most of the fluorescence that could not be controlled by the reflecting surface is emitted to the parabolic side. By utilizing this characteristic, a wide range on the parabolic side of the headlamp 10 can be illuminated.

(Window part 6)
Next, the light irradiation unit 1 is disposed outside the half parabolic mirror 5, and the half parabolic mirror 5 is formed with a window portion 6 that transmits or passes laser light. The window 6 may be an opening or may include a transparent member that can transmit laser light. For example, a transparent plate provided with a filter that transmits laser light and reflects white light (fluorescence of the light emitting section 4) may be provided as the window section 6. In this configuration, the fluorescence of the light emitting unit 4 can be prevented from leaking from the window unit 6.

  According to the above configuration, the light emitting unit 4 can be irradiated with laser light from the outside of the half parabolic mirror 5 through the window 6 provided in the half parabolic mirror 5. Therefore, the degree of freedom of arrangement of the light irradiation unit 1 can be increased, and for example, it becomes easy to set the irradiation angle of the laser light with respect to the light irradiation surface of the light emitting unit 4 to a preferable angle.

  Next, one common window portion 6 may be provided for the plurality of light irradiation units 1, or a plurality of window portions 6 corresponding to each light irradiation unit 1 may be provided.

  In the half parabolic mirror 5 of the present embodiment, as an example of the shape of the reflecting mirror, the parabolic shape is a half parabolic shape which is a partial curved surface obtained by cutting along a plane including the rotation axis. Is not limited to this.

  For example, the shape of the reflecting mirror may be a parabola, or may be a partial curved surface or a hemispherical surface of a part of a spheroid. That is, the reflecting mirror only needs to include at least a part of a curved surface formed by rotating a figure (ellipse, circle, parabola) about the rotation axis on the reflecting surface.

(Metal base 7)
The metal base 7 is a plate-like support member that supports the light emitting unit 4 and is made of metal (for example, copper or iron). Therefore, the metal base 7 has high thermal conductivity, and can efficiently dissipate heat generated by the light emitting unit 4. In addition, the member which supports the light emission part 4 is not limited to what consists of metals, The member containing substances (glass, sapphire, etc.) with high heat conductivity other than a metal may be sufficient. However, it is preferable that the surface of the metal base 7 in contact with the light emitting unit 4 functions as a reflecting surface. Since the surface is a reflecting surface, the laser light incident from the upper surface of the light emitting unit 4 is converted into fluorescence, and then reflected by the reflecting surface and can be directed to the half parabolic mirror 5. Alternatively, the laser light incident from the upper surface of the light emitting unit 4 can be reflected by the reflecting surface and again directed to the inside of the light emitting unit 4 to be converted into fluorescence.

  In the headlamp 10 of the present embodiment, the metal base 7 is made of copper, and aluminum is vapor-deposited on the surface on the side where the light emitting unit 4 is disposed. On the back side, fins 8 having a length of 30 mm and a width of 1 mm described later are provided at intervals of 5 mm. Note that the metal base 7 and the fins 8 may be integrally formed.

  Since the metal base 7 is covered with the half parabolic mirror 5, it can be said that the metal base 7 has a surface facing the reflecting surface of the half parabolic mirror 5. It is preferable that the surface of the metal base 7 on the side where the light emitting unit 4 is provided is substantially parallel to the rotation axis of the paraboloid of the half parabolic mirror 5 and substantially includes the rotation axis.

(Fin 8)
The fin 8 functions as a cooling unit (heat dissipation mechanism) that cools the metal base 7. The fin 8 has a plurality of heat radiating plates, and increases the heat radiation efficiency by increasing the contact area with the atmosphere. The cooling unit that cools the metal base 7 may have a cooling (heat radiation) function, and may be a heat pipe, a water cooling method, or an air cooling method.

(Details of the light irradiation unit 1)
Next, based on FIG. 3 and 4, the detail of the light irradiation unit 1 mentioned above is demonstrated. FIG. 3 is a diagram showing the configuration of the light irradiation unit 1, FIG. 3A is a perspective view showing the appearance of the light irradiation unit 1, and FIG. It is sectional drawing which shows the structure of a cap part.

  As shown in FIG. 3B, the light irradiation unit 1 has a magnifying lens 3 mounted on the tip side of the cap portion of a 5.6 mmφ laser package 2.

  In addition, a laser chip LC fixed on the stem ST exists inside the laser package 2. The laser chip LC is a semiconductor laser element that functions as a laser light source that emits laser light. This laser chip LC may have one light emitting point P per chip, or may have a plurality of light emitting points P per chip. The oscillation wavelength of the laser chip LC is 405 nm and the output is 1 W.

  As the magnifying lens 3, a lens suitable for exciting the light emitting unit 4 having the diameter of the circle on the bottom surface of 2 mmφ may be selected. The lens diameter d of the magnifying lens 3 is 1.5 mm, and the effective lens diameter er is 1.0 mm.

  Here, the distance d1 is a distance from the cap bottom B to the light emitting point P of the laser chip LC, and is 1.5 mm. The distance d2 is a distance from the light emitting point P to the lens center C of the magnifying lens 3, and is 1.5 mm. Of course, the laser chip LC and the magnifying lens 13 are optically adjusted. The cap height h is 3.0 mm, and the cap thickness t is 0.12 mm.

  Next, the function of the light irradiation unit 1 is demonstrated based on FIG.

  As shown in FIG. 4, the light irradiation unit 1 emits laser light while the laser light gradually spreads (while the beam diameter monotonously increases), and W = 2 mmφ even at a distance D = 60 mm away. It was found that a small area can be irradiated.

  In this case, energy of 90% or more of the light output from the laser chip LC can reach the 2 mmφ region 60 mm away, which shows that the efficiency is very high.

  In the light irradiation unit 1 described above, laser light is not excessively collected on the light emitting unit 4, unlike the case where the condenser lens L as shown in FIG. .

  Further, in the light irradiation unit 1, the alignment between the laser chip LC and the magnifying lens 3 at the time of manufacture and the optical axis adjustment can be performed with high accuracy.

  For example, in manufacturing (cap alignment), a manufacturing method using active alignment that determines the position of a lens-attached cap while monitoring the spot diameter and position of light emitted through the magnifying lens 3 while weakly emitting laser light. Is used, the positional relationship between the laser chip LC and the magnifying lens 3 provided on the cap can be determined more precisely.

  In the light irradiation unit 1, the area (irradiation area) of the spot of the laser light irradiated on the light irradiation surface of the light emitting unit 4 is larger than the light emission area of the light emission point P of the laser chip LC that emits the laser light. Is preferred.

  In particular, since the light emitting unit 4 of the present embodiment has a cylindrical shape with a circle having a diameter of 2 mmφ as a bottom surface, the area (irradiation area) of the spot of the laser beam irradiated on the light irradiation surface of the light emitting unit 4 is 0. It is preferable that it is 1 mmφ or more and 2 mmφ or less.

  Thereby, since the diverged laser light is irradiated onto the light irradiation surface of the light emitting unit 4, there is no place where the light density of the laser light becomes too high on the light irradiation surface of the light emitting unit 4.

  The magnifying lens 3 is a lens disposed on the optical path of the laser light emitted from the laser chip LC, and it is preferable that the beam diameter of the laser light after passing through the lens monotonously increases. Thereby, since the laser light after passing through the lens is diverged, the laser light is not condensed on the light irradiation surface of the light emitting unit 4, and a portion where the light density of the laser light becomes too high does not occur.

  In the light irradiation unit 1, it is preferable that the area of the spot of the laser light incident on the magnifying lens 3 from the laser chip LC (irradiation area with respect to the lens surface) is smaller than the area of the light irradiation surface of the light emitting unit 4. As a result, the laser light after passing through the magnifying lens 3 diverges, so that the laser light is not condensed on the light irradiation surface of the light emitting unit 4, and there are places where the light density of the laser light becomes too high. Absent.

[2. Configuration of headlamp 20]
Next, FIG. 5 is a schematic diagram showing a configuration of a headlamp (vehicle headlamp, lighting device) 20 according to another embodiment of the present invention. The headlamp 20 is an illumination device that projects fluorescence generated from the light emitting unit 4.

  As shown in FIG. 5B, the headlamp 20 mainly includes (1) a total of eight light irradiation units 1 described above, and (2) three from the left side with respect to the paper surface-2. It differs from the headlamp 10 in that it is a three-dimensional arrangement in which the three-piece arrangement (hereinafter referred to as a three-stage arrangement) is packed most closely. In the headlamp 20 of the present embodiment, the fins 8 included in the headlamp 10 are not provided, but whether or not the fins 8 are provided can be selected as appropriate.

(Details of the light irradiation unit 1)
As described above, the light irradiation unit 1 has a 1 W output for emitting 405 nm laser light, and a total of eight light irradiation units are provided. Therefore, the total output of the laser beam is 8W.

  The light irradiation unit 1 irradiates the light emitting unit 4 with laser light through the window 6 via the magnifying lens 3. More specifically, the light spot is expanded so that the laser beam is irradiated in the vicinity of the center of the light emitting unit 4 (to be described later) (the focal position of the half parabolic mirror 5) with an area of 2 mmΦ. Laser light emitted from each of the three-stage light irradiation units 1 is applied to the light emitting unit 4 through the window 6 in the range of an incident angle of 30 to 70 °.

(Details of the light emitting unit 4)
The light emitting unit 4 is mixed with three types of RGB phosphors so as to emit white light. The red phosphor is CaAlSiN ₃ : Eu, the green phosphor is β-SiAlON: Eu, and the blue phosphor is (BaSr) MgAl ₁₀ O ₁₇ : Eu.

  These phosphor powders are uniformly mixed in a resin (for example, silicone resin) and applied onto the metal base 7.

  The shape of the light emitting unit 4 is, for example, a cylindrical shape (disc shape) having a diameter of 10 mmΦ of a bottom circle and a thickness of 0.1 mm.

(Details of half parabolic mirror 5)
The opening of the half parabolic mirror 5 (right side with respect to the paper surface) is a semicircle having a radius of 30 mm, and the depth of the half parabolic mirror 5 (width in the left-right direction with respect to the paper surface) is 30 mm. The light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

(Details of metal base 7)
The metal base 7 is made of copper, and aluminum is vapor-deposited on the surface on the side where the light emitting unit 4 is disposed. Thereby, the light emission part 4 can be cooled with the metal base 7, and it can prevent that the light emission efficiency of the light emission part 4 falls by the temperature rise by a laser beam.

(Effect of the headlamp 20)
In the headlamp 20, the half parabolic mirror 5 is installed so as to cover the upper part of the light emitting unit 4, so that the ratio of the fluorescence that can control the course of the fluorescence emitted from the light emitting unit 4 can be increased. Most of the fluorescence from the light emitting unit 4 can be controlled by the half parabolic mirror 5.

  Even in this case, the fluorescence emitted from the side surface of the light emitting unit 4 (side emission fluorescence) can be controlled, and there is a high possibility that the light is projected outside the front surface.

  However, since the area of the light emitting surface of the light emitting unit 4 is larger than the area of the laser light spot, the side emission fluorescence is reduced. Therefore, with the above configuration, fluorescence that cannot be controlled by the half parabolic mirror 5 can be reduced, and the use efficiency of fluorescence can be increased.

  Further, the light emitting unit 4 can be irradiated with laser light from the outside of the half parabolic mirror 5 through the window 6 provided in the half parabolic mirror 5. Therefore, the degree of freedom of arrangement of the light irradiation unit 1 can be increased, and for example, it becomes easy to set the irradiation angle of the laser light with respect to the light irradiation surface of the light emitting unit 4 to a preferable angle.

[3. Configuration of headlamp 30]
Next, FIG. 6 is a schematic diagram showing a configuration of a headlamp (vehicle headlamp, illumination device) 30 which is still another embodiment of the present invention. The headlamp 30 is an illumination device that projects fluorescence generated from the light emitting unit 4.

  As shown in FIG. 6B, the headlamp 30 mainly includes (1) a total of five light irradiation units 1 described above, and (2) along the outer surface of the half parabolic mirror 5 ( Different from the above-described headlamp 10 in that each light irradiation unit 1 is arranged (from the upper side to the lower side with respect to the paper surface) and the light emitting unit 4 is irradiated with laser light through a plurality of windows 6. .

(Details of the light irradiation unit 1)
The light irradiation unit 1 has a 1 W output for emitting 405 nm laser light, and a total of five light irradiation units are provided. Therefore, the total output of the laser beam is 5W.

  The light irradiation unit 1 irradiates the light emitting unit 4 with laser light through the magnifying lens 3 and through a total of five window portions 6 corresponding to the respective light irradiation units 1. More specifically, the laser light is applied to the entire light emitting section 4 having a cylindrical shape with a diameter of a circle on the bottom surface of 2 mmΦ, in the vicinity of the center of the light emitting section 4 described later (the focal position of the half parabolic mirror 5). So that the light spot is enlarged.

(Details of the light emitting unit 4)
The constituent material of the light emitting unit 4 is the same as that described in the headlamp 20, but the size of the light emitting unit 4 is different.

  The shape and size of the light emitting unit 4 of the headlamp 20 of the present embodiment are, for example, a cylindrical shape (disk shape) having a diameter of 2 mmΦ of a circle on the bottom surface and a thickness of 0.1 mm.

(Details of half parabolic mirror 5)
The opening (right side with respect to the paper surface) of the half parabolic mirror 5 of the headlamp 20 of the present embodiment is a semicircle having a radius of 25 mm, and the depth (width in the left-right direction with respect to the paper surface) of the half parabolic mirror 5 is 45 mm. It is. The light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

(Details of metal base 7)
The metal base 7 is made of copper, and aluminum is vapor-deposited on the surface on the side where the light emitting unit 4 is disposed. On the back side, fins 8 having a length of 25 mm and a width of 1 mm are provided at intervals of 5 mm. Thereby, the heat from the light emitting unit 4 and the heat derived from the laser light are radiated.

  Thereby, the light emission part 4 can be cooled with the metal base 7, and it can prevent that the light emission efficiency of the light emission part 4 falls by the temperature rise by a laser beam. Note that the metal base 7 and the fins 8 may be integrally formed.

(Effect of headlamp 30)
In the headlamp 30, by installing the half parabolic mirror 5 so as to cover the upper part of the light emitting unit 4, it is possible to increase the ratio of the fluorescence that can control the course of the fluorescence emitted from the light emitting unit 4, Most of the fluorescence from the light emitting unit 4 can be controlled by the half parabolic mirror 5.

  Moreover, in the headlamp 30, since the whole light emission part 4 is irradiated with a laser beam from another direction, the light emission efficiency of the light emission part 4 can be improved more.

  Further, the light emitting unit 4 can be irradiated with laser light from the outside of the half parabolic mirror 5 through the window 6 provided in the half parabolic mirror 5. Therefore, the degree of freedom of arrangement of the light irradiation unit 1 can be increased, and for example, it becomes easy to set the irradiation angle of the laser light with respect to the light irradiation surface of the light emitting unit 4 to a preferable angle.

[4. Configuration of headlamp 40]
Next, FIG. 7 is a schematic diagram showing a configuration of a headlamp (vehicle headlamp, lighting device) 40 which is still another embodiment of the present invention. The headlamp 40 is an illumination device that projects fluorescence generated from the light emitting unit 4.

  As shown in FIG. 7, the headlamp 40 includes a light irradiation unit (light irradiation unit) 1 a, a light emitting unit 4, a half parabolic mirror 5, a metal base 7, and fins 8.

  The light irradiation unit 1 a includes a set of a plurality of LD (laser elements) 2 a and a condenser lens 11, a plurality of optical fibers 12, a magnifying lens (increasing rate changing element, lens) 13, and a reflection mirror 14. The light irradiation unit 1a of this embodiment is an example when a light irradiation part is comprised with several optical components. Like the light irradiation unit 1a of the present embodiment, the magnifying lens 3 is not limited to the one that directly receives the laser light from the LD 2a, but may be any one that controls the laser light irradiated to the light emitting unit 4. good.

  The condensing lens 11 is a lens for causing the laser light oscillated from the LD 2 a to enter an incident end which is one end of the optical fiber 12. A set of the LD 2a and the condenser lens 11 is associated with each of the plurality of optical fibers 12 on a one-to-one basis. That is, the LD 2 a is optically coupled to the optical fiber 12 through the condenser lens 11.

  The optical fiber 12 is a light guide member that guides the laser light oscillated by the LD 2 a to the light emitting unit 4. The optical fiber 12 has a two-layer structure in which the core of the core is covered with a clad having a refractive index lower than that of the core, and the laser light incident from the incident end passes through the inside of the optical fiber 12 and the other side. The light is emitted from the emission end which is the end of the. The exit end of the optical fiber 12 is bundled with a ferrule or the like.

  The laser beam emitted from the emission end of the optical fiber 12 is enlarged by the magnifying lens 13 so as to be applied to the entire light emitting unit 4 having a light irradiation surface with a diameter of 2 mmΦ. The expanded laser beam is reflected by the reflection mirror 14 to change the optical path, and is guided to the light emitting unit 4 through the window unit 6 of the half parabolic mirror 5. The laser light is applied to the light emitting unit 4 at an angle of 45 °.

(Details of LD2a)
The LD 2 a is a normal 5 mmΦ semiconductor laser package not equipped with the magnifying lens 3 provided at the tip of the cap portion of the light irradiation unit 1. The LD 2a has a 1W output for emitting 405 nm laser light, and a total of eight LDs 2a are provided. Therefore, the total output of the laser beam is 8W.

(Details of the light emitting unit 4)
The constituent material of the light emitting unit 4 is the same as that described in the headlamp 20, but the size of the light emitting unit 4 is different. The shape and size of the light emitting unit 4 are, for example, a cylindrical shape (disc shape) having a diameter of 2 mmΦ and a thickness of 0.2 mm.

(Details of half parabolic mirror 5)
The opening of the half parabolic mirror 5 is a semicircle having a radius of 30 mm, and the depth of the half parabolic mirror 5 is 30 mm. The light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

(Details of metal base 7)
The metal base 7 is made of copper, and aluminum is vapor-deposited on the surface on the side where the light emitting unit 4 is disposed. Thereby, the light emission part 4 can be cooled with the metal base 7, and it can prevent that the light emission efficiency of the light emission part 4 falls by the temperature rise by a laser beam. On the back side of the metal base 7, fins 8 having a length of 30 mm and a width of 1 mm are provided at intervals of 5 mm. Note that the metal base 7 and the fins 8 may be integrally formed.

(Effect of headlamp 40)
In the headlamp 40, since the half parabolic mirror 5 is installed so as to cover the upper part of the light emitting unit 4, the ratio of the fluorescence that can control the course of the fluorescence emitted from the light emitting unit 4 can be increased. Most of the fluorescence from the light emitting unit 4 can be controlled by the half parabolic mirror 5.

  Further, the light emitting unit 4 can be irradiated with laser light from the outside of the half parabolic mirror 5 through the window 6 provided in the half parabolic mirror 5. Therefore, the degree of freedom of arrangement of the light irradiation unit 1a can be increased, and for example, it becomes easy to set the irradiation angle of the laser light with respect to the light irradiation surface of the light emitting unit 4 to a preferable angle.

[5. Configuration of headlamp 50]
Next, FIG. 8 is a schematic diagram showing a headlamp (vehicle headlamp, lighting device) 50 according to still another embodiment of the present invention. The headlamp 50 is an illumination device that projects fluorescence generated from the light emitting unit 4.

  As shown in FIG. 8, the headlamp 50 includes a light irradiation unit (light irradiation unit) 1 b, a light emitting unit 4, a half parabolic mirror 5, and a metal base 7.

  The light irradiation unit 1b includes a set of a total of ten LDs 2a and a condenser lens 11, ten optical fibers 12, a magnifying lens 13, and a reflection mirror 14.

  In the headlamp 50, an opening 7 a is provided in the metal base 7, and laser light is irradiated from the bottom side to the paper surface of the light emitting unit 4 through the opening 7 a.

  Therefore, it is not necessary to form the window portion 6 in the half parabolic mirror 5, the area of the reflection surface of the half parabolic mirror 5 can be substantially increased, and the amount of fluorescence that can be controlled can be increased. Like the light irradiation unit 1b of the present embodiment, the light irradiation surface of the light emitting unit 4 is not only a surface facing the half parabolic mirror 5, but also a hidden surface that is not visible from the half parabolic mirror 5 side. good.

  In addition, the light emission part 4 may be arrange | positioned so that the opening part 7a of the metal base 7 may be larger than the opening part 7a of the metal base 7, as shown in FIG. 8, and the light emission of the magnitude | size substantially the same as the opening part 7a. The part 4 may be fitted into the opening 7a.

  The condenser lens 11 and the optical fiber 12 are as described above.

  The laser beam emitted from the emission end of the optical fiber 12 is irradiated to the light emitting unit 4 through the opening 7 a via the magnifying lens 13. More specifically, the light spot is expanded so that the laser beam is irradiated in the vicinity of the center of the light emitting unit 4 (to be described later) (the focal position of the half parabolic mirror 5) with an area of 2 mmΦ.

  The expanded laser light is reflected by the reflection mirror 14 to change the optical path, and is guided to the light emitting unit 4 through the opening 7 a of the metal base 7. The laser light is applied to the light emitting unit 4 at an angle of 90 °.

  In the headlamp 50 of the present embodiment, the area of the light emitting surface of the light emitting unit 4 is larger than the area of the spot of the laser beam, so that the side emission fluorescence is reduced. Therefore, with the above configuration, fluorescence that cannot be controlled by the half parabolic mirror 5 can be reduced, and the use efficiency of fluorescence can be increased.

(Details of LD2a)
The LD 2a is a normal semiconductor laser package of 5 mmΦ in which the magnifying lens 13 is not attached to the cap portion described above. Further, the LD 2a has a 1 W output for emitting a laser beam of 405 nm, and a total of ten LDs 2a are provided. Therefore, the total output of the laser light is 10W.

(Details of the light emitting unit 4)
The constituent material of the light emitting unit 4 is the same as that described in the headlamp 20, but the size of the light emitting unit 4 is different. The shape and size of the light emitting unit 4 are, for example, a cylindrical shape (disc shape) having a diameter of 5 mmΦ and a thickness of 0.1 mm.

  The light emitting unit 4 is made by sintering and hardening the phosphor.

(Details of half parabolic mirror 5)
The opening of the half parabolic mirror 5 is a semicircle having a radius of 30 mm, and the depth of the half parabolic mirror 5 is 30 mm. The light emitting unit 4 is disposed at the focal position of the half parabolic mirror 5.

(Details of metal base 7)
The metal base 7 is a metal mirror whose surface is coated with silver. On the back side of the metal base 7, fins 8 having a length of 30 mm and a width of 1 mm are provided at intervals of 5 mm. Note that the metal base 7 and the fins 8 may be integrally formed.

(Effect of headlamp 50)
In the headlamp 40, since the half parabolic mirror 5 is installed so as to cover the upper part of the light emitting unit 4, the ratio of the fluorescence that can control the course of the fluorescence emitted from the light emitting unit 4 can be increased. Most of the fluorescence from the light emitting unit 4 can be controlled by the half parabolic mirror 5.

  Moreover, it is not necessary to form an opening for transmitting the laser beam in the half parabolic mirror 5, the area of the reflecting surface of the half parabolic mirror 5 can be substantially increased, and the amount of fluorescence that can be controlled can be increased.

[Additional Notes]
The present invention is not limited to the above-described embodiments and examples, and various modifications can be made within the scope shown in the claims, and obtained by appropriately combining technical means disclosed in different examples. Such embodiments are also included in the technical scope of the present invention.

[Summary]
A light-emitting device according to aspect 1 of the present invention includes a light-emitting unit that generates fluorescence when irradiated with laser light, and a reflecting mirror that has a curved surface that reflects fluorescence generated from the light-emitting unit on an inner wall, and the light-emitting device. A part of the reflecting mirror is disposed at a position facing a light emitting surface which is a surface opposite to the light irradiation surface irradiated with the laser light, and the reflecting mirror is disposed on the light irradiation surface side. Is not arranged.

  Further, in the light emitting device according to aspect 2 of the present invention, in the aspect 1, the laser light applied to the light irradiation surface has a positive beam diameter increase rate with respect to the propagation direction of the laser light. It may be.

  The light-emitting device according to aspect 3 of the present invention further includes an increase rate changing element that emits light by decreasing the increase rate of the beam diameter with respect to the propagation direction of the laser light emitted from the laser light source. Also good.

  In the light emitting device according to aspect 4 of the present invention, in the aspect 3, the increase rate changing element may be a lens disposed on an optical path of laser light emitted from the laser light source.

  Moreover, the light-emitting device which concerns on aspect 5 of this invention WHEREIN: The circumference | surroundings of the said light emission part may be supported by the heat conductive member in the said aspects 1-4.

  The vehicle headlamp according to the sixth aspect of the present invention may include the light emitting device according to the first to fifth aspects.

  The lighting device according to aspect 7 of the present invention may include the light-emitting device according to aspects 1 to 5 described above.

[Supplement]
The present invention can also be expressed as follows. That is, the light emitting device of the present invention irradiates the light emitting surface of the light emitting portion with the light emitting portion that generates fluorescence when irradiated with the laser light and the laser light whose beam diameter monotonously increases in the propagation direction. And a light irradiation unit.

  According to the above configuration, the light irradiation surface of the light emitting unit is irradiated with laser light whose beam diameter monotonously increases in the propagation direction (laser light). Therefore, the location where the light density of the laser beam becomes too high does not occur on the light irradiation surface of the light emitting portion. As a result, it is possible to prevent degradation of the light emitting portion and a decrease in light emission efficiency due to temperature rise.

Note that the “light irradiation surface” may be one of a plurality of surfaces constituting the light emitting unit, or may be a plurality of surfaces. The “beam diameter” is the maximum diameter of a region where the light intensity is 1 / e ² or less of the maximum intensity. “The beam diameter monotonously increases in the propagation direction” means that the value of the rate of increase of the beam diameter with respect to the propagation distance of the laser beam is positive or 0 at any position on the optical path (however, at all positions). It is not necessary to have a constant value at any position on the optical path.

  Further, in the light emitting device of the present invention, in addition to the above configuration, the area of the laser light spot irradiated on the light irradiation surface of the light emitting unit is greater than the light emitting area of the light emitting point of the laser light source that emits the laser light. Is also preferably large.

  In the above configuration, the spot area (irradiation area) of the laser beam irradiated on the light irradiation surface of the light emitting unit is larger than the light emission area of the light emission point of the laser light source. Thereby, since the diverged laser light is irradiated on the light irradiation surface of the light emitting unit, a portion where the light density of the laser light is too high does not occur on the light irradiation surface of the light emitting unit.

  In addition to the above-described configuration, the light emitting device of the present invention further includes an increase rate changing element that emits the light irradiation unit while decreasing the increase rate of the beam diameter with respect to the propagation direction of the laser light emitted from the laser light source. You may have.

  According to the above configuration, the laser beam with respect to the light irradiation surface can be reduced by reducing the increase rate of the beam diameter after the emission, in addition to the distance between the laser light source and the light emitting unit and the area of the light irradiation surface of the light emitting unit. Can be prevented from becoming larger than the area of the light irradiation surface.

  Further, in the light emitting device of the present invention, in addition to the above configuration, the increase rate changing element is a lens disposed on an optical path of laser light emitted from the laser light source, and the laser after passing through the lens It is preferable that the beam diameter of light increases monotonously.

  According to the above configuration, since the laser light after passing through the lens diverges, the laser light is not condensed on the light irradiation surface of the light emitting unit, and there is a portion where the light density of the laser light becomes too high. Absent.

  In addition to the above configuration, the light emitting device of the present invention preferably has an area of a spot of laser light incident on the lens from the laser light source smaller than an area of the light irradiation surface of the light emitting unit.

  According to the above configuration, since the laser light after passing through the lens diverges, the laser light is not condensed on the light irradiation surface of the light emitting unit, and there is a portion where the light density of the laser light becomes too high. Absent.

  In the light emitting device of the present invention, in addition to the above configuration, the light irradiation unit may include a housing for storing the laser light source, and the housing and the increase rate changing element may be integrated. .

  According to the above configuration, the relative positional relationship between the laser light source and the increase rate changing element does not shift due to vibration / aging deterioration of the light irradiation unit. In addition, the number of parts of the light irradiation unit can be reduced, and the overall size of the light irradiation unit can be reduced.

  In addition to the above configuration, the light emitting device of the present invention includes a reflecting mirror that reflects the fluorescence generated from the light emitting unit, and a part of the reflecting mirror is disposed above the light irradiation surface of the light emitting unit. The area of the spot of the laser beam irradiated on the light irradiation surface of the light emitting unit may be smaller than the light irradiation surface.

  According to the said structure, since the light irradiation surface of a light emission part has opposed the reflective mirror, the ratio of the fluorescence which can control the course among the fluorescence radiate | emitted from the light emission part can be raised.

  Even in this case, the fluorescence emitted from the side surface of the light emitting unit (side emission fluorescence) can be controlled, and there is a high possibility that the light is projected outside the front surface.

  However, since the area of the light irradiation surface is larger than the area of the laser light spot, the side emission fluorescence is reduced. Therefore, with the above configuration, it is possible to reduce fluorescence that cannot be controlled by the reflecting mirror, and it is possible to increase the use efficiency of fluorescence.

  In addition to the above-described structure, the light-emitting device of the present invention includes a rotating paraboloid formed by rotating the parabola with the parabolic symmetry axis as a rotation axis, and a plane including the rotation axis. You may have as a reflective surface at least one part of the partial curved surface obtained by cut | disconnecting by.

  According to the above configuration, the reflecting mirror has a part of a partial curved surface obtained by cutting the paraboloid on the plane including the rotation axis as the reflecting surface. Can be efficiently projected within a narrow solid angle, and as a result, the utilization efficiency of fluorescence can be increased. In addition, a structure other than the parabola can be arranged in a portion corresponding to the other half of the parabola.

  Furthermore, in the above configuration, most of the fluorescence that could not be controlled by the reflecting mirror is emitted to the parabolic side. By utilizing this characteristic, a wide range on the parabolic side of the light emitting device can be illuminated.

  In the light emitting device of the present invention, in addition to the above configuration, the laser light source is disposed outside the reflecting mirror, and a window portion through which the laser light is transmitted or passed is provided in the reflecting mirror. Also good.

  According to the said structure, a laser beam can be irradiated to a light emission part from the exterior of a reflective mirror through the window part provided in the reflective mirror. Therefore, the degree of freedom of arrangement of the laser light source can be increased, and for example, it becomes easy to set the irradiation angle of the laser light with respect to the light irradiation surface of the light emitting unit to a preferable angle.

  The window portion may be an opening portion or may have a transparent member that can transmit laser light.

  In the light emitting device of the present invention, in addition to the above configuration, the light emitting unit may be supported by a heat conducting member.

  According to the said structure, a light emission part can be cooled with a heat conductive member, and it can prevent that the light emission efficiency of a light emission part falls by the temperature rise by a laser beam.

  In addition to the above configuration, in the light emitting device of the present invention, an opening may be formed in the heat conducting member, and the laser light may be applied to the light emitting portion through the opening.

  According to the above configuration, it is not necessary to form an opening for transmitting the laser light to the reflecting mirror, the area of the reflecting surface of the reflecting mirror can be substantially increased, and the amount of fluorescence that can be controlled can be increased.

  Further, the vehicle headlamp and the lighting device including the light emitting device are also included in the technical scope of the present invention.

  The laser element of the present invention includes a laser light source that emits laser light, and a lens that is disposed on the optical path of the laser light emitted from the laser light source, and the propagation of the laser light after passing through the lens. And a lens whose beam diameter with respect to the direction increases monotonously.

  Since it is possible to provide a laser element capable of emitting laser light whose beam diameter with respect to the propagation direction monotonously increases (diverges), it is a component suitable for the light emitting device.

  In addition to the above configuration, the laser element of the present invention preferably includes a housing for storing the laser light source, and the housing and the lens are integrated.

  According to the above configuration, the relative positional relationship between the laser light source and the lens does not shift due to vibration / aging deterioration of the laser element. Further, the number of parts of the laser element can be reduced, and the size of the entire laser element can be reduced.

  The laser element and the light emitting device of the present invention can be applied not only to a vehicle headlamp but also to other lighting devices. An example of the other lighting device is a downlight. A downlight is a lighting device installed on the ceiling of a structure such as a house or a vehicle. In addition, the illumination device of the present invention may be realized as a headlamp of a moving object other than a vehicle (for example, a human, a ship, an aircraft, a submersible, a rocket), a searchlight, a projector, a down You may implement | achieve as indoor lighting fixtures (stand lamp etc.) other than a light.

1 Light irradiation unit (light irradiation unit, laser element)
1a Light irradiation unit (light irradiation unit)
1b Light irradiation unit (light irradiation unit)
2 Laser package (housing)
2a LD (laser element)
3 Magnifying lens (Increasing rate changing element, lens)
4 Light-emitting part 5 Half parabolic mirror (reflecting mirror)
6 Window 7 Metal base (heat conduction member)
7a Opening 10 Headlamp (light emitting device, vehicle headlamp)
13 Magnifying lens (Increasing rate changing element, lens)
20 Headlamp (light emitting device, vehicle headlamp)
30 Headlamp (light emitting device, vehicle headlamp)
40 Headlamp (light emitting device, vehicle headlamp)
50 Headlamp (light emitting device, vehicle headlamp)
LC laser chip (laser light source)
P luminous point

Claims (7)

A light-emitting unit that generates fluorescence when irradiated with laser light;
A reflecting mirror having an inner wall with a curved surface that reflects the fluorescence generated from the light emitting unit,
In the light emitting unit, a part of the reflecting mirror is disposed at a position facing a light emitting surface which is a surface opposite to a light irradiation surface irradiated with the laser light,
The reflecting mirror is not arranged on the light irradiation surface side ,
The light emitting unit is supported by a heat conducting member,
The light emitting device , wherein the light irradiation surface is irradiated with laser light through an opening provided in the heat conducting member .   2. The light emitting device according to claim 1, wherein the laser light applied to the light irradiation surface has a positive value of an increase rate of a beam diameter with respect to a propagation direction of the laser light. A light-emitting unit that generates fluorescence when irradiated with laser light;
A reflecting mirror having an inner wall with a curved surface that reflects the fluorescence generated from the light emitting unit,
In the light emitting unit, a part of the reflecting mirror is disposed at a position facing a light emitting surface which is a surface opposite to a light irradiation surface irradiated with the laser light,
The reflecting mirror is not arranged on the light irradiation surface side,
The laser beam irradiated to the light irradiation surface has a positive value of the increase rate of the beam diameter with respect to the propagation direction of the laser beam,
Light emission device you further comprising a growth rate change device emitting reduces the rate of increase of the beam diameter to the propagation direction of the laser beam emitted from the laser light source.   4. The light emitting device according to claim 3, wherein the increase rate changing element is a lens disposed on an optical path of laser light emitted from the laser light source.   The light emitting device according to any one of claims 1 to 4, wherein a periphery of the light emitting unit is supported by a heat conductive member.   A vehicle headlamp comprising the light emitting device according to any one of claims 1 to 5.   An illuminating device comprising the light emitting device according to claim 1.