JP6085204B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device, and more particularly to a light emitting device using a phosphor.

  In recent years, a light emitting diode (LED) or the like is provided as an excitation light source, and the light generated by irradiating the light emitting member (wavelength conversion member) including the phosphor with the excitation light emitted from the excitation light source is irradiated. A light emitting device is known.

  In such a light emitting device using a phosphor, a configuration has been proposed in which the excitation light source and the light emitting member are separated from each other in order to avoid deterioration of the phosphor due to heat generated in the excitation light source. In this configuration, the light emitting member is different in its light emission method, and the light emitting member that emits light mainly from the surface facing the irradiation surface irradiated with the excitation light (hereinafter referred to as a transmissive light emitting member) and the excitation light. Are classified into light emitting members that emit light mainly from the irradiated surface (hereinafter referred to as reflective light emitting members).

  As shown in FIG. 15A, in the transmissive light emitting member 203, excitation light incident from the irradiation surface 232 is transmitted through the light emitting member 203 and includes fluorescence from the emission surface 233 facing the irradiation surface 232. Mainly emitted as light. On the other hand, as shown in FIG. 15B, in the reflective light emitting member 203, the excitation light incident from the irradiation surface 232 is reflected by a reflection member (not shown) provided on the bottom surface of the irradiation surface 232, It is emitted mainly from the irradiation surface 232 as light containing fluorescence.

  For example, Patent Literature 1 discloses a light emitting device 301 including a reflective light emitting member 303. As shown in FIG. 16, the light emitting device 301 has a configuration in which a light emitting member 303 containing a phosphor is applied over the inner surface of the reflector 304 and the light emitting member 303 is excited by the LED 302. According to the light emitting device 301, there is no color unevenness, and mutual absorption can be suppressed by separately applying the light emitting member 303. Moreover, the reflector 304 has a heat dissipation function, and the heat of the LED 302 can be efficiently dissipated.

JP 2009-76494 A (released on April 9, 2009)

  Here, in a conventional light emitting device such as Patent Document 1, a phosphor having a particle diameter of about several microns is usually used. For this reason, as shown in FIG. 17A, most of the excitation light irradiated to the light emitting member 403 is scattered by the phosphor 431 existing in the vicinity of the irradiation surface 432. Therefore, the excitation efficiency of the phosphor 431 existing inside the light emitting member 403 away from the irradiation surface 432 is greatly reduced.

  Therefore, in order to maintain the excitation efficiency of the phosphor 431, it is necessary to reduce the thickness of the light emitting member 403 and increase the area of the irradiation surface 432 as shown in FIG. Further, it is necessary to limit the content of the phosphor 431 dispersed in the light emitting member 403 so that the excitation light is not scattered by the phosphor 431 existing in the vicinity of the irradiation surface 432.

  On the other hand, in order to increase the luminance of the light emitting member 403 while keeping the volume constant, the area of the light emitting surface is reduced while maintaining the luminous intensity, or the content of the phosphor 431 included in the light emitting member 403 is increased. It is necessary to let

  Therefore, the conventional light emitting device in which the shape of the light emitting member 403 and the content of the phosphor 431 are limited has a problem that sufficient luminance cannot be obtained.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a light-emitting device with improved luminance.

  In order to solve the above problems, a light-emitting device according to one embodiment of the present invention includes a light source that emits excitation light, and a nanoparticle phosphor that emits fluorescence in response to the excitation light emitted from the light source. A light emitting member that emits light containing the fluorescence, an inner surface that reflects the light emitted from the light emitting member, and a reflective member that has an opening for emitting the light, the light source comprising: The light emitting member is irradiated with the excitation light from the opening side, and the light emitting member has an irradiation surface on which the excitation light is irradiated, and the inner surface is configured to mainly emit the light from the irradiation surface. It is arranged on the side.

  According to one embodiment of the present invention, the luminance of a light-emitting member that functions as a main light-emitting surface can be increased because an irradiation surface irradiated with excitation light can be provided, and thus a light-emitting device with improved luminance can be provided. There is an effect.

FIG. 1 is a cross-sectional view showing a configuration of a light emitting device according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view for explaining the operation of the light emitting device shown in FIG. 3A and 3B are cross-sectional views for explaining the luminance of the wavelength conversion member shown in FIG. FIG. 4 is a top view showing a modification of the number of LEDs arranged in FIG. FIG. 5 is a perspective view showing a modification of the reflector shown in FIG. FIG. 6 is a cross-sectional view showing a modification of the arrangement position of the LEDs shown in FIG. FIG. 7 is a cross-sectional view showing a configuration of a light emitting device according to Embodiment 2 of the present invention. FIG. 8 is a cross-sectional view showing a modification of the heat dissipation member shown in FIG. FIG. 9A is a perspective view showing the appearance of the outdoor lighting device provided with the light emitting device shown in FIG. 1, and FIG. 9B shows the inside of the main body shown in FIG. FIG. FIG. 10 is a perspective view showing an arrangement state of the plurality of light emitting devices and the light projecting lens shown in FIG. FIG. 11 is a perspective view showing an external appearance of a projector using a combination of the plurality of light emitting devices and the projection lens shown in FIG. FIG. 12 is a side view showing an example of a combination of the light-emitting device and the optical fiber shown in FIG. FIG. 13 is a perspective view showing an appearance of a lighting device using a combination of the light emitting device and the optical fiber shown in FIG. It is a perspective view which shows an example of the combination of the light-emitting device and light guide member which are shown by FIG. FIG. 15A and FIG. 15B are cross-sectional views for explaining the light emission method of the wavelength conversion member. FIG. 16 is a cross-sectional view illustrating a configuration of a conventional light emitting device. FIGS. 17A and 17B are cross-sectional views for explaining the relationship between the thickness of the wavelength conversion member and the excitation efficiency.

Embodiment 1
An embodiment according to an aspect of the present invention will be described below with reference to FIGS. In the present embodiment, a light emitting device 1 that emits light of a desired color by mixing excitation light and fluorescence will be described.

[Configuration of Light Emitting Device 1]
First, the configuration of the light emitting device 1 will be described with reference to FIG.

  FIG. 1 is a cross-sectional view illustrating a configuration of a light emitting device 1 according to the present embodiment. As shown in FIG. 1, the light emitting device 1 includes an LED (light source) 2, a wavelength conversion member (light emitting member) 3, a reflector (reflecting member) 4, a light distribution lens 5, and a base 6. . Hereinafter, the structure of each part with which the light-emitting device 1 is provided is demonstrated.

(LED2)
The LED 2 is an excitation light source that emits excitation light L1 for exciting the nanoparticle phosphor 31 included in the wavelength conversion member 3. The LED 2 may have one light emitting point on one chip, or may have a plurality of light emitting points on one chip.

  The emission wavelength of the LED 2 is, for example, 450 nm (blue), but an LED having a wavelength in the blue region of 420 nm to 490 nm can be selected. Moreover, the emission wavelength of LED2 should just be suitably selected according to the kind of nanoparticle fluorescent substance 31 contained in the wavelength conversion member 3, and is good also as a wavelength different from blue. The LED 2 may use another excitation light source such as a laser.

  In the present embodiment, two LEDs 2 are arranged in the vicinity of the opening 41 of the reflector 4. More specifically, the two LEDs 2 are attached to the inner surface 42 of the reflector 4 so as to be separated from each other in the diameter direction of the opening 41 of the reflector 4. Further, the angles of the two LEDs 2 are adjusted so that the wavelength conversion member 3 is irradiated with the excitation light (L1). Thereby, the LED 2 can irradiate the wavelength conversion member 3 with the excitation light L <b> 1 from the opening 41 side of the reflector 4.

  By arranging the LED 2 in this way, the excitation light L1 can be suitably irradiated from the opening 41 side of the reflector 4 to the wavelength conversion member 3. Moreover, since it becomes possible to arrange | position LED2 inside the reflector 4, the light-emitting device 1 can be reduced in size.

  In addition, the number and arrangement position of LED2 are not limited to this structure, It can select suitably. For example, one LED 2 may be arranged in the light emitting device 1, or three or more LEDs 2 may be arranged. Moreover, LED2 should just be arrange | positioned in the position which can irradiate the excitation light L1 to the irradiation surface 32 of the wavelength conversion member 3, and may be arrange | positioned outside the reflector 4. FIG.

(Wavelength conversion member 3)
The wavelength conversion member 3 is a light emitting member that receives the excitation light L1 emitted from the LED 2 and emits light. The wavelength conversion member 3 includes a nanoparticle phosphor 31 that emits fluorescence upon receiving the excitation light L1, and emits light L2 including fluorescence when irradiated with the excitation light L1.

  The wavelength conversion member 3 has an irradiation surface 32 to which the excitation light L1 is irradiated, and is disposed on the inner surface 42 side of the reflector 4 so as to mainly emit light L2 from the irradiation surface 32. That is, the wavelength conversion member 3 is a reflective light emitting member in which the irradiation surface 32 functions as a main light emitting surface.

  In the present embodiment, the wavelength conversion member 3 is disposed on the bottom surface 42 a of the reflector 4 with the irradiation surface 32 facing the opening 41 of the reflector 4. Further, the wavelength conversion member 3 is disposed so that the surfaces other than the irradiation surface 32 are in contact with the bottom surface 42 a of the reflector 4. Therefore, the light L <b> 1 directed toward the joint surface between the wavelength conversion member 3 and the inner surface 42 can be reflected by the bottom surface 42 a toward the irradiation surface 32 of the wavelength conversion member 3, and the light L <b> 2 can be emitted from the irradiation surface 32. Thereby, the irradiation surface 32 can be functioned as a light emission surface with a simple structure.

  In the wavelength conversion member 3, a nanoparticle phosphor 31 is dispersed inside an acrylic resin as a sealing material. However, the sealing material is not limited to acrylic resin, and may be silicone resin, so-called organic-inorganic hybrid glass, or inorganic glass.

  Preferable examples of the nanoparticle phosphor 31 dispersed in the sealing material include binary nanocrystalline compound semiconductors composed of II-VI group compound semiconductors and III-V group compound semiconductors. Examples of the II-VI group compound semiconductor include CdSe, ZnS, ZnSe, and examples of the III-V group compound semiconductor include InN, InP, GaN, and the like. Further, a ternary or quaternary compound in which a II-VI group compound or a III-V group compound is combined may be used.

  Even if compound semiconductors having the same composition (for example, indium phosphide: InP) are used, it is possible to change the emission size by changing the particle size of the nanoparticle phosphor 31. One of the features. For example, InP emits red light when the particle size is about 3 to 4 nm.

  Since the nanoparticle phosphor 31 is based on a semiconductor, the fluorescence lifetime is short, and the excitation energy absorbed from the excitation light L1 can be quickly emitted as fluorescence, so that the nanoparticle phosphor 31 is also resistant to the high-power excitation light L1. This is because the emission lifetime of the nanoparticle phosphor 31 is about 10 nanoseconds, which is five orders of magnitude shorter than that of a normal phosphor having a rare-earth emission center.

  As a result, high efficiency can be maintained with respect to the strong excitation light L1, and heat generation from the nanoparticle phosphor 31 is reduced. Therefore, deterioration (discoloration or deformation) due to heat generated in the wavelength conversion member 3 can be suppressed.

  Thus, by using the nanoparticle phosphor 31 having a particle size of the order of nanometers, the ratio of the excitation light L1 irradiated to the irradiation surface 32 of the wavelength conversion member 3 being scattered in the vicinity of the irradiation surface 32 is reduced. Can do. Therefore, as will be described later, it is possible to increase the thickness of the wavelength conversion member 3 as compared with the conventional case, and it is possible to reduce the area of the irradiation surface 32 that functions as the light emitting surface. Moreover, by using the nanoparticle phosphor 31, it becomes possible to contain more phosphor particles in the wavelength conversion member 3, and the content of the phosphor contained in the wavelength conversion member 3 can be increased.

(Reflector 4)
The reflector 4 is a reflecting member that projects light L2 emitted from the wavelength conversion member 3 in a predetermined direction. More specifically, the reflector 4 reflects the light L2 emitted from the wavelength conversion member 3 to form a light bundle that travels within a predetermined solid angle.

  The reflector 4 has an inner surface 42 that reflects the light L2 emitted from the wavelength conversion member 3, and an opening 41 for emitting the light L2 to the outside. The inner surface 42 of the reflector 4 includes a closed bottom surface 42a located on the side opposite to the opening 41, and the wavelength conversion member 3 is disposed on the bottom surface 42a.

  In the present embodiment, a parabolic mirror having a circular opening 41 is used as the reflector 4. In other words, the reflector 4 has at least a part of a partial curved surface obtained by cutting a curved surface formed by rotating the parabola about the axis of symmetry of the parabola as a rotational axis along a plane including the rotational axis. Is included.

  However, the reflector 4 is not limited to a parabolic mirror, and may be, for example, an elliptical mirror, a free-form curved mirror, or a multi-mirror, and can be changed as appropriate.

  As a material of the reflector 4, for example, a metal (for example, Al, Cu) having a high reflectance of the light L <b> 2 emitted from the wavelength conversion member 3 and a higher thermal conductivity than the LED 2 and the wavelength conversion member 3 is used. It is preferable to adopt. Thereby, the heat generated in the LED 2 and the wavelength conversion member 3 can be efficiently radiated.

  When Cu is employed as the material of the reflector 4, it is preferable to metallize a reflective layer such as a Ni layer / Ag layer or a Ni layer / Al layer on the inner surface 42.

  In addition, the material of the reflector 4 is not limited to metal, and a resin or ceramic having a higher thermal conductivity than the LED 2 and the wavelength conversion member 3 may be employed. In this case, for example, when a resin is used, it is preferable to deposit a copper foil on the inner surface 42 and metallize a reflective layer such as a Ni layer / Ag layer or a Ni layer / Al layer on the copper foil.

(Light distribution lens 5)
The light distribution lens 5 is an optical member for making the light L2 emitted from the reflector 4 substantially parallel light. The light distribution lens 5 is a plano-convex lens in which the light incident surface side on which the light L2 is incident is formed in a flat shape, and the light emitting surface from which the light L2 is emitted is formed in a convex curved surface shape. The light distribution lens 5 is disposed at the end of the reflector 4 so as to close the opening 41 of the reflector 4.

(Base 6)
The base 6 is a holding member that holds the reflector 4. The base 6 is preferably made of a metal or the like having a thermal conductivity equal to or higher than that of the reflector 4. Thereby, the heat of the reflector 4 can be efficiently conducted to the base 6 and radiated.

[Operation of Light Emitting Device 1]
Next, the operation of the light emitting device 1 will be described with reference to FIG.

  FIG. 2 is a cross-sectional view for explaining the operation of the light emitting device 1 shown in FIG. As shown in FIG. 2, the excitation light L <b> 1 emitted from the LED 2 enters the wavelength conversion member 3 from the irradiation surface 32, and a part of the excitation light L <b> 1 is fluorescent by the nanoparticle phosphor 31 included in the wavelength conversion member 3. Is converted to And the light L2 containing excitation light L1 and fluorescence is radiate | emitted from the irradiation surface 32 of the wavelength conversion member 3, and is projected in a predetermined direction.

  As described above, the light emitting device 1 mixes the excitation light L1 emitted from the LED 2 and the fluorescence generated by the nanoparticle phosphor 31 to generate and irradiate light L2 having a desired color. is there.

  For example, by irradiating the wavelength conversion member 3 including the green nanoparticle phosphor 31a and the red nanoparticle phosphor 31b with 450 nm (blue) excitation light L1, green light from the green nanoparticle phosphor 31a is emitted. The light emitting device 1 can irradiate white light L2 in which fluorescence, red fluorescence from the red nanoparticle phosphor 31b, and blue excitation light are mixed.

(Details of wavelength conversion member 3)
Next, the details of the wavelength conversion member 3 will be described with reference to FIG.

  FIG. 3A and FIG. 3B are cross-sectional views for explaining the luminance of the wavelength conversion member 3. As described above, in the conventional light emitting device, since a phosphor having a particle size of about several microns was used, the shape of the wavelength conversion member and the phosphor content were limited, and sufficient luminance could not be obtained. .

  Luminance is the luminous intensity per unit area. Therefore, in order to increase the luminance of the wavelength conversion member while keeping the volume constant, the area of the light emitting surface is reduced while maintaining the luminous intensity, or the content of the phosphor contained in the wavelength conversion member is increased. There is a need.

  Therefore, the light emitting device 1 includes the wavelength conversion member 3 including the nanoparticle phosphor 31 having a particle size of the order of nanometers. Since the nanoparticle phosphor 31 has a smaller particle size than that of a conventionally used phosphor, the rate at which the excitation light L1 irradiated to the irradiation surface 32 of the wavelength conversion member 3 is scattered in the vicinity of the irradiation surface 32 is reduced. Can be made.

  Therefore, even when the thickness of the wavelength conversion member 3 (width in the direction perpendicular to the irradiation surface 32) is increased, excitation of the nanoparticle phosphor 31 existing inside the wavelength conversion member 3 away from the irradiation surface 32 Excitation can be done without significantly reducing efficiency.

  Therefore, according to the light emitting device 1, it is possible to increase the thickness of the wavelength conversion member 3 (width in the direction perpendicular to the irradiation surface 32) compared to the conventional case. Therefore, as shown in FIG. 3A, the area of the irradiation surface 32 functioning as the light emitting surface can be reduced, and therefore the luminance of the wavelength conversion member 3 can be increased.

  In addition, by using the nanoparticle phosphor 31, it becomes possible to include more phosphor particles in the wavelength conversion member 3. Therefore, as shown in FIG. 3B, the content of the phosphor contained in the wavelength conversion member 3 can be increased, so that the luminance of the wavelength conversion member 3 can be increased.

  As described above, by using the nanoparticle phosphor 31, the luminance of the wavelength conversion member 3 can be increased, and the luminance of the light emitting device 1 can be improved.

  In addition, it is preferable that the wavelength conversion member 3 is disposed with the irradiation surface 32 facing the opening 41 of the reflector 4. Thereby, since the emission direction of the light L1 of the light emitting device 1 and the thickness direction of the wavelength conversion member 3 can be made to coincide, the wavelength conversion unit is applied to the wavelength conversion part over the inner surface of the reflector as in the past. It becomes possible to make the thickness of the conversion member 3 sufficiently large. Therefore, the luminance of the light emitting device 1 can be effectively improved.

  In addition, since the wavelength conversion member 3 is disposed with the irradiation surface 32 facing the opening 41 of the reflector 4, it is possible to control the alignment of the light L <b> 1 with the reflector 4 with high accuracy. Characteristics can be improved.

  Moreover, the wavelength conversion member 3 should just be arrange | positioned so that the light L1 may mainly be emitted from the irradiation surface 32 with which the excitation light L1 is irradiated, and does not necessarily need to contact | abut the inner surface 42 of the reflector 4. FIG. For example, the wavelength conversion member 3 may be arranged so that a slight gap exists between the wavelength conversion member 3 and the inner surface 42 of the reflector 4. Alternatively, the wavelength conversion member 3 may be mounted on a mounting table or the like whose surface is mirror-finished, and the mounting table may be fixed to the bottom surface 42 a of the reflector 4 or the like.

[Effect of light-emitting device 1]
As described above, the light emitting device 1 according to the present embodiment includes the LED 2 that emits the excitation light L1, and the nanoparticle phosphor 31 that emits fluorescence by receiving the excitation light L1 emitted from the LED 2, and includes the fluorescence. The LED 2 includes a wavelength conversion member 3 that emits light L2, an inner surface 42 that reflects the light L2 emitted from the wavelength conversion member 3, and a reflector 4 that has an opening 41 for emitting the light L2. The wavelength conversion member 3 is irradiated with excitation light L1 from the opening 41 side, and the wavelength conversion member 3 has an irradiation surface 32 on which the excitation light L1 is irradiated, and the light L2 is mainly emitted from the irradiation surface 32. It arrange | positions at the inner surface 42 side of the reflector 4 so that it may radiate | emit.

  In the light emitting device 1, the LED 2 irradiates the wavelength conversion member 3 with the excitation light L1 from the opening 41 side of the reflector 4, and the wavelength conversion member 3 emits the light L2 from the irradiation surface 32 irradiated with the excitation light L1. Is arranged on the inner surface 42 side of the reflector 4 so as to emit mainly. That is, in the wavelength conversion member 3, the irradiation surface 32 irradiated with the excitation light L1 functions as a main light emitting surface.

  Here, the light emitting device 1 includes a wavelength conversion member 3 having a nanoparticle phosphor 31. Since the nanoparticle phosphor 31 has a smaller particle size than that of a conventionally used phosphor, the proportion of the excitation light L1 irradiated to the irradiation surface 32 of the wavelength conversion member 3 is scattered in the vicinity of the irradiation surface 32. Can be reduced.

  Therefore, excitation can be performed without greatly reducing the excitation efficiency of the nanoparticle phosphor 31 existing inside the wavelength conversion member 3 away from the irradiation surface 32. Therefore, according to the light emitting device 1, it is possible to increase the thickness of the wavelength conversion member 3 as compared with the conventional case. Therefore, since the area of the irradiation surface 32 that functions as the main light emitting surface can be reduced, the luminance, which is the luminous intensity per unit area, can be increased.

  In addition, by using the nanoparticle phosphor 31, it becomes possible to include more phosphor particles in the wavelength conversion member 3. Therefore, according to the light-emitting device 1, since the content of the phosphor contained in the wavelength conversion member 3 can be increased, the luminance of the wavelength conversion member 3 can be increased.

  Thus, according to the present embodiment, the luminance of the wavelength conversion member 3 that functions as the main light emitting surface can be increased by the irradiation surface 32 irradiated with the excitation light L1, and thus the light emitting device with improved luminance. 1 can be realized.

[Modification]
Next, with reference to FIGS. 4-6, the modification regarding the light-emitting device 1 is demonstrated.

(Modification 1)
FIG. 4 is a top view showing a modification of the number of LEDs 2 arranged. In the above-described embodiment, the two LEDs 2 are arranged on the reflector 4, but the present invention is not limited to this.

  As shown to (a) of FIG. 4, the light-emitting device 1 may be the structure by which three or more (4 in the figure) LED2 is arrange | positioned. In this case, the four LEDs 2 may be attached to the inner surface 42 so as to be equally spaced along the circumference of the opening 41 of the reflector 4.

  Thus, since the excitation efficiency of the nanoparticle phosphor 31 can be increased by arranging three or more LEDs 2, the luminance of the light emitting device 1 can be further improved.

  As shown in FIG. 4B, the light emitting device 1 may have a configuration in which one LED 2 is arranged. Thereby, since the number of parts of the light-emitting device 1 can be reduced, the manufacturing cost of the light-emitting device 1 can be reduced.

(Modification 2)
FIG. 5 is a perspective view showing a modification of the reflector 4. In the above-described embodiment, the parabolic reflector 4 having the circular opening 41 is used, but the present invention is not limited to this. The shape of the reflector 4 can be appropriately changed according to the purpose and application of the light emitting device 1.

  For example, as shown in FIG. 5, a reflector 4a having a reverse trapezoidal cross-sectional tendency when cut along a plane perpendicular to the longitudinal direction may be used. In the reflector 4a, the wavelength conversion member 3 is disposed on the inner surface 42 on the short side of the inverted trapezoid, and a rectangular opening 41a is formed on the long side.

  In the reflector 4a, a plurality of LEDs 2 are arranged at equal intervals along the longitudinal direction of the opening 41a of the reflector 4a, and are attached to the inner surface 42 in the vicinity of the opening 41a.

  Thus, the shape of the reflector 4 is not limited, and may be a shape having an inner surface 42 composed of a plurality of planes.

(Modification 3)
FIG. 6 is a cross-sectional view showing a modified example of the arrangement position of the LED 2. In the above-described embodiment, the LED 2 is attached to the inner surface 42 of the reflector 4, but the present invention is not limited to this.

  As in the light emitting device 1 a illustrated in FIG. 6, the LED 2 may be arranged in a state where it is embedded in the reflector 4 so that a part of the LED 2 is exposed to the outside of the reflector 4. Thereby, the heat generated in the LED 2 can be efficiently radiated to the outside.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. In the present embodiment, the light emitting device 11 further including a heat radiating member will be described.

  For convenience of explanation, members having the same functions as those described in the embodiment are given the same reference numerals, and descriptions thereof are omitted.

[Configuration of Light Emitting Device 11]
FIG. 7 is a cross-sectional view showing a configuration of the light emitting device 11 according to the present embodiment. As shown in FIG. 7, the light emitting device 11 is mainly different from the light emitting device 1 according to the first embodiment in that the light emitting device 11 further includes a heat radiating member 7 in addition to the light emitting device 1.

(Heat dissipation member 7)
The heat radiating member 7 is a heat conducting member for radiating the heat generated by the LED 2 to the outside of the light emitting device 11. The heat dissipating member 7 is provided between the LED 2 and the reflector 4 and the light distribution lens 5, and releases heat received from the joint surface of the LED 2 from the end exposed to the outside.

  The heat radiating member 7 is made of a material having a high thermal conductivity, and can be formed of, for example, a thin film of a metal (for example, Al, Ag) material having a high thermal conductivity.

[Effect of light-emitting device 11]
As described above, the light emitting device 11 includes the heat radiating member 7 for radiating the heat generated in the LED 2, and a part of the heat radiating member 7 is joined to the LED 2. Therefore, the heat radiating member 7 can directly receive the heat generated in the LED 2 from the joint surface and radiate the received heat to the outside of the light emitting device 11.

  Therefore, according to the present embodiment, it is possible to realize the light emitting device 11 having a high heat dissipation effect and improved luminance.

[Modification]
Next, with reference to FIG. 8, the modification regarding the light-emitting device 11 is demonstrated.

  FIG. 8 is a cross-sectional view showing a modification of the heat dissipating member 7 shown in FIG. In the above-described embodiment, a part of the heat dissipation member 7 is bonded to the LED 2, but the present invention is not limited to this.

  As shown in FIG. 8, a configuration in which a part of the heat radiating member 7 is embedded in the outer surface of the reflector 4 may be used. In this case, the heat radiating member 7 can receive the heat generated in the LED 2 and the wavelength converting member 3 through the reflector 4 and radiate the heat to the outside.

  In the present configuration, it is preferable that the heat radiating member 7 is made of a metal having a thermal conductivity equivalent to or higher than that of the reflector 4. Thereby, the heat of the reflector 4 can be efficiently conducted to the heat radiating member 7 to be radiated.

[Embodiment 3]
The following will describe still another embodiment of the present invention with reference to FIGS. In the present embodiment, a lighting device including the light emitting device 1 according to the first embodiment will be described.

  For convenience of explanation, members having the same functions as those described in the embodiment are given the same reference numerals, and descriptions thereof are omitted.

[Configuration of Outdoor Lighting Device 101]
First, with reference to FIG. 9 and FIG. 10, the structure of the outdoor illuminating device (illuminating device) 101 provided with the light-emitting device 1 is demonstrated.

  FIG. 9A is a perspective view showing an appearance of the outdoor lighting device 101 including the light emitting device 1, and FIG. 9B is a perspective view showing the inside of the main body 102 shown in FIG. 9A. FIG.

  As shown in FIG. 9A and FIG. 9B, the outdoor lighting device 101 includes a main body 102, a light projecting lens 103, and a support base 104. A plurality of light emitting devices 1 are arranged side by side.

(Main body 102)
The main body 102 is a housing that encloses the light emitting device 1. The main body 102 has a cylindrical shape with only one end opened, and a plurality of light emitting devices 1 are arranged in a matrix in the main body 102. In this way, by arranging a plurality of light emitting devices 1 that are small and have high brightness, high output illumination can be realized.

(Projecting lens 103)
The light projecting lens 103 is an optical member for condensing light emitted from the plurality of light emitting devices 1 disposed inside the main body 102 and projecting the light in a predetermined direction.

  FIG. 10 is a perspective view showing an arrangement state of the plurality of light emitting devices 1 and the light projecting lens 103. As shown in FIG. 10, the light projecting lens 103 is disposed so as to close the opening 102 a of the main body 102, and a plurality of light emitting devices 1 are arranged on the incident surface side of the light projecting lens 103. By using the light projecting lens 103, light emitted from the plurality of light emitting devices 1 can be refracted and projected within a predetermined angle range. Therefore, by combining the plurality of light emitting devices 1 and the light projecting lens 103, it is possible to project light far away by controlling the optical path of the light emitted from the plurality of light emitting devices 1 with high accuracy.

[Effect of outdoor lighting device 101]
As described above, the outdoor lighting device 101 includes a plurality of light emitting devices 1 and projects light emitted from the plurality of light emitting devices 1 using the light projecting lens 103. Since the light emitting device 1 can be easily downsized, a large number of light emitting devices 1 can be arranged in a limited arrangement space. Therefore, according to this embodiment, the high-intensity outdoor lighting device 101 can be realized.

  Next, the configuration of the projector (illumination device) 111 including the light emitting device 1 will be described with reference to FIG.

[Configuration of Projector 111]
FIG. 11 is a perspective view showing an external appearance of a projector 111 using a combination of the plurality of light emitting devices 1 and the light projecting lens 103 shown in FIG. As shown in FIG. 11, the projector 111 includes a housing 112 and a light projecting lens 103, and a plurality of light emitting devices 1 (not shown) are arranged in the opening 112 a of the housing 112.

(Case 112)
The housing 112 is a housing that encloses the light emitting device 1, and has an opening 112 a on one side surface. The projection lens 103 is fitted into the opening 112a, and a plurality of light emitting devices 1 are arranged in a matrix on the incident surface side of the projection lens 103.

[Effect of projector 111]
As described above, the combination of the plurality of light emitting devices 1 and the projection lens 103 can be suitably applied not only to the outdoor lighting device 101 but also to the projector 111 and the like, and the projector 111 with high brightness can be realized. it can.

[Other application examples]
Next, other application examples of the light-emitting device 1 will be described with reference to FIGS.

(Application example 1)
FIG. 12 is a side view showing an example of a combination of the light emitting device 1 and the optical fiber 114 shown in FIG.

(Optical fiber 114)
The optical fiber 114 is a light guide member that guides light emitted from the light emitting device 1. The optical fiber 114 has an incident end face 114a on which light emitted from the light emitting device 1 is incident, and an outgoing end face 114b (see FIG. 13) that emits light incident from the incident end face 114a.

  The optical fiber 114 has a two-layer structure in which an inner core is covered with a clad having a refractive index lower than that of the core. The core is mainly composed of quartz glass (silicon oxide) having almost no light absorption loss. The clad is mainly composed of quartz glass or a synthetic resin material having a refractive index lower than that of the core.

  Such a combination of the light emitting device 1 and the optical fiber 114 can be suitably applied to a soft endoscope (soft endoscope) such as a gastric camera, and thus a high-brightness endoscope can be obtained. Can be realized.

[Configuration of Lighting Device 121]
FIG. 13 is a perspective view showing an external appearance of a lighting device 121 using a combination of the light emitting device 1 and the optical fiber 114 shown in FIG. As illustrated in FIG. 13, the illumination device 121 includes the light emitting device 1, a condenser lens 122, an optical fiber 114, and a tip portion 123.

(Condensing lens 122)
The condensing lens 122 is an optical member that condenses the light emitted from the light emitting device 1 and guides it to the incident end surface 114 a of the optical fiber 114.

(Tip portion 123)
The tip portion 123 is for emitting light guided through the optical fiber 114. The distal end portion 123 is connected to the emission end face 114b of the optical fiber 114, and radiates light emitted from the emission end face 114b within a predetermined angular range. Therefore, the front end portion 123 may include a lens for controlling the angle of light emitted from the emission end surface 114b.

[Effect of lighting device 121]
In this way, by combining the light emitting device 1 and the optical fiber 114, it is easy to dispose the distal end portion 123 away from the LED 2 of the light emitting device 1. Therefore, the heat generation at the distal end portion 123 can be suppressed.

  Therefore, by applying the illumination device 121 to an endoscope, a safe and high-brightness endoscope can be realized.

(Application example 2)
FIG. 14 is a perspective view showing an example of a combination of the light emitting device 1 and the light guide member 115 shown in FIG.

(Light guide member 115)
The light guide member 115 guides the light emitted from the light emitting device 1. The light guide member 115 has an incident end face 115a for allowing the light emitted from the light emitting device 1 to enter, and an exit end face 115b for emitting the light incident from the incident end face 115a. The light guide member 115 totally reflects the light incident from the incident end surface 115a on the inner surface and emits the light from the output end surface 115b. Therefore, the emission end face 115b can function as a light emitting point.

  By combining the light emitting device 1 and the light guide member 115, it becomes easy to dispose the emission end face 115 b functioning as a light emitting point away from the LED 2 of the light emitting apparatus 1, thereby suppressing heat generation at the emission end face 115 b. It becomes possible.

  Such a combination of the light emitting device 1 and the light guide member 115 can be suitably applied to a rigid endoscope (rigid endoscope) and the like, whereby a safe and high brightness endoscope. Can be realized.

[Summary]
A light-emitting device according to aspect 1 of the present invention includes a light source (LED 2) that emits excitation light and a nanoparticle phosphor that emits fluorescence in response to excitation light emitted from the light source, and includes light including the fluorescence. A light emitting member (wavelength converting member 3) that emits light, an inner surface that reflects the light emitted from the light emitting member, and a reflective member (reflector 4) that has an opening for emitting the light, the light source Irradiates the light emitting member with the excitation light from the opening side, and the light emitting member has an irradiation surface on which the excitation light is irradiated, and mainly emits the light from the irradiation surface. It is arrange | positioned at the said inner surface side.

  In the above configuration, the light source irradiates the light emitting member with excitation light from the opening side of the reflecting member, and the light emitting member emits light mainly from the irradiation surface irradiated with the excitation light. It is arranged on the inner surface side. That is, the light emitting member functions as a main light emitting surface where the irradiation surface irradiated with excitation light is irradiated.

  In the present invention, “mainly emitting light from the irradiated surface” means that the most light is emitted from the irradiated surface among the surfaces constituting the light emitting member.

  Here, the light-emitting device includes a light-emitting member having a nanoparticle phosphor. Since the nanoparticle phosphor has a particle size smaller than that of conventionally used phosphors, it is possible to reduce the rate at which the excitation light irradiated on the irradiation surface of the light emitting member is scattered in the vicinity of the irradiation surface.

  Therefore, excitation can be performed without significantly reducing the excitation efficiency of the nanoparticle phosphor existing inside the light emitting member away from the irradiation surface. Therefore, according to said structure, it becomes possible to enlarge the thickness (width | variety of a direction perpendicular | vertical to an irradiation surface) of a light emitting member compared with the past. Therefore, since the area of the irradiation surface that functions as the main light emitting surface can be reduced, the luminance that is the luminous intensity per unit area can be increased.

  Further, by using the nanoparticle phosphor, it becomes possible to contain more phosphor particles in the light emitting member. Therefore, according to said structure, since the content of the fluorescent substance contained in a light emitting member can be increased compared with the past, the brightness | luminance of a light emitting member can be raised.

  As described above, according to the above configuration, since the luminance of the light emitting member that functions as the main light emitting surface can be improved, the light emitting device with improved luminance can be realized. Can do.

  In the light-emitting device which concerns on aspect 2 of this invention, in the said aspect 1, it is preferable that the said light emission member is arrange | positioned with the said irradiation surface facing the said opening part.

  In the above configuration, since the light emitting member is disposed with the irradiation surface functioning as the main light emitting surface facing the opening of the reflecting member, the light emission direction of the light emitting device matches the thickness direction of the light emitting member. Can be made.

  Therefore, according to the above configuration, the thickness of the light emitting member can be sufficiently increased as compared with the conventional configuration in which the wavelength conversion member is applied over the inner surface of the reflecting member. It can be improved effectively.

  In addition, since the light emitting member is arranged with the irradiation surface functioning as the main light emitting surface facing the opening of the reflecting member, it becomes possible to control the alignment of light with high accuracy by the reflecting member. Characteristics can be improved.

  In the light emitting device according to aspect 3 of the present invention, in the above aspect 1 or 2, the inner surface includes a closed bottom surface located on the side opposite to the opening, and the light emitting member is disposed on the bottom surface. It is preferable.

  According to said structure, since the light emitting member is arrange | positioned at the bottom face of a reflective member, the light inside a light emitting member which goes to the joint surface of a light emitting member and a bottom face is reflected in a bottom face, and it is on the irradiation surface of a light emitting member. Can be directed.

  Therefore, according to said structure, the light emitting member which mainly emits light from an irradiation surface can be obtained easily.

  In the light-emitting device which concerns on aspect 4 of this invention, it is preferable in the said aspect 3 that the surface except the said irradiation surface is contacting the said inner surface.

  According to said structure, since the surface of the light emission member except an irradiation surface is in contact with the inner surface of a reflection member, light can be radiate | emitted only from the irradiation surface of a light emission member.

  Therefore, according to the above configuration, the luminance of the light emitting member can be further increased.

  In the light emitting device according to aspect 5 of the present invention, in any of the above aspects 1 to 4, the light source is preferably disposed on the inner surface in the vicinity of the opening of the reflecting member.

  In said structure, since the light source is arrange | positioned at the inner surface of the opening part vicinity of a reflection member, a light source and a light emitting member can be arrange | positioned in a reflection member.

  Therefore, according to said structure, excitation light can be irradiated suitably from an opening part side with respect to a wavelength conversion member, and a light-emitting device can be reduced in size.

  In the light-emitting device which concerns on aspect 6 of this invention, in any one of the said aspects 1-5, it is preferable to further provide the heat radiating member for radiating the heat which arose in the said light source or the said light-emitting member.

  In said structure, since the heat radiating member for radiating the heat | fever generated with the light source or the light emitting member is further provided, the heat dissipation effect of a light source or a light emitting member can be improved.

  Therefore, according to the above configuration, a highly reliable light-emitting device having excellent heat resistance can be obtained.

  An illumination device (outdoor illumination device 101 / projector 111) according to aspect 7 of the present invention includes the light-emitting device according to any one of aspects 1 to 6.

  Therefore, according to said structure, the illuminating device which improved the brightness | luminance is realizable.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

  The present invention can be applied to various illumination devices such as an outdoor illumination device, a projector, and an endoscope.

DESCRIPTION OF SYMBOLS 1 Light-emitting device 1a Light-emitting device 2 LED (light source)
3 Wavelength conversion member (light emitting member)
4 reflector (reflective member)
7 Radiating member 31 Nanoparticle phosphor 31a Green nanoparticle phosphor 31b Red nanoparticle phosphor 32 Irradiation surface 41 Opening portion 41a Opening portion 42 Inner surface 42a Bottom surface 101 Outdoor illumination device (illumination device)
111 Projector (lighting device)
121 Illuminator L1 Excitation light L2 light

Claims (6)

A light source that emits excitation light;
A nanoparticle phosphor that emits fluorescence in response to the excitation light emitted from the light source, and a light emitting member that emits light including the fluorescence;
An inner surface for reflecting the light emitted from the light emitting member, and a reflecting member having an opening for emitting the light,
The light source irradiates the light emitting member with the excitation light from the opening side,
The light emitting member has an irradiation surface irradiated with the excitation light, and is disposed on the inner surface side so as to mainly emit the light from the irradiation surface .
The light emitting device according to claim 1, wherein a thickness of the light emitting member in a direction perpendicular to the irradiation surface is larger than a width of the irradiation surface in a direction perpendicular to the thickness direction of the light emitting member . A light source that emits excitation light;
A nanoparticle phosphor that emits fluorescence in response to the excitation light emitted from the light source, and a light emitting member that emits light including the fluorescence;
An inner surface for reflecting the light emitted from the light emitting member, and a reflecting member having an opening for emitting the light,
The light source irradiates the light emitting member with the excitation light from the opening side,
The light emitting member has an irradiation surface irradiated with the excitation light, and is disposed on the inner surface side so as to mainly emit the light from the irradiation surface.
The light emitting device, wherein a part of the light source is embedded in the reflecting member so as to be exposed outside a space defined by the inner surface of the reflecting member. The light emitting member is the light-emitting device according to claim 1 or 2, characterized in that the irradiation surface is disposed toward the opening. The inner surface includes a closed bottom surface located opposite the opening;
The light emitting member is the light-emitting device according to any one of claims 1 to 3, characterized in that it is arranged on the bottom surface. The light emitting device according to claim 4 , wherein a surface of the light emitting member is in contact with the inner surface except for the irradiation surface. The light emitting device according to any one of claims 1 to 5 , further comprising a heat radiating member for radiating heat generated by the light source or the light emitting member.

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