JP2004266030A - Lighting apparatus and display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting apparatus and a display apparatus which can radiate an almost constant amount of fluorescence without being affected by the ambient temperature. <P>SOLUTION: The lighting apparatus is provided with a semiconductor laser element (100) which radiates induced emitted light, a layer (102) including a semiconductor which absorbs such induced emitted light and radiates spontaneously emitted light, and a layer (103) which includes a fluorescent material in which an emission center is added to a mother crystal in order to absorb the spontaneously emitted light and radiate fluorescent light of different wavelength. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lighting device and a display device, and more particularly to a lighting device including a phosphor in which a luminescent center is added to a host crystal so as to convert the wavelength of light emitted from a semiconductor laser element to emit fluorescence of various colors. The present invention relates to a device and a display device.
[0002]
[Prior art]
An illuminating device using a phosphor capable of absorbing visible light by absorbing laser light emitted from a semiconductor laser element is disclosed in Japanese Patent Application Laid-Open No. Hei 7-282609 of Patent Document 1. Also, a light emitting device using a phosphor capable of absorbing laser light and emitting visible light outside the clad portion of an optical fiber optically connected to a semiconductor laser element is disclosed in Japanese Patent Application Laid-Open No. 2002-148442 of Patent Document 2. It is disclosed in the gazette.
[0003]
As described above, when a semiconductor laser element is used as a basic light source, (1) power / light conversion efficiency is better, (2) high light output is possible, and (3) radiation Since such light has strong directivity, the advantage is obtained that the light diameter can be narrowed down. That is, in the semiconductor laser device, the excitation light is incident on a lighting device of Patent Document 1 in which emission of excitation light in a predetermined direction toward the phosphor is desired, or a light guide such as an optical fiber having a small diameter as in Patent Document 2. Suitable as a basic light source for
[0004]
Further, an example of a display device using a laser element and a phosphor is disclosed in Japanese Patent Application Laid-Open No. 7-20818 of Patent Document 3.
[0005]
As shown in the above prior art documents, the optical configuration using a phosphor that can emit a fluorescent light of various colors by converting the wavelength of the laser light emitted from the semiconductor laser element as a basic light source, The present invention can be preferably applied to a lighting device and a display device.
[0006]
[Patent Document 1]
JP-A-7-282609
[0007]
[Patent Document 2]
JP-A-2002-148442
[0008]
[Patent Document 3]
JP-A-7-20818
[0009]
[Problems to be solved by the invention]
The inventor of the present invention has disclosed a lighting device and a display device which include a combination of a semiconductor laser element and a phosphor capable of emitting a fluorescent light of various colors by converting the wavelength of the laser light as described above. It was found that the environmental temperature dependence of the amount of fluorescence was large.
[0010]
In view of such a problem, an object of the present invention is to provide a lighting device and a display device that can emit a substantially constant amount of fluorescence without being affected by the environmental temperature.
[0011]
[Means for Solving the Problems]
A lighting device according to one embodiment of the present invention is a semiconductor laser element that emits stimulated emission light, a layer that includes a semiconductor that absorbs the stimulated emission light and emits spontaneous emission light, and absorbs the spontaneous emission light. And a layer containing a phosphor in which an emission center is added to a base crystal so as to emit fluorescence of different wavelengths.
[0012]
Note that the semiconductor laser device can be mounted on a frame, a semiconductor that emits spontaneous emission light can be included in a first cap material that covers the semiconductor laser device, and the phosphor has a first cap material. It can be included in the covering second cap material. Further, the lighting device may further include a light guide for propagating the stimulated emission light and irradiating the semiconductor with at least a part of the light. In this way, it is possible to obtain a point-like or planar lighting device in which the amount of fluorescence from the phosphor is less dependent on the environmental temperature.
[0013]
A display device according to another aspect of the present invention includes a semiconductor laser element that emits stimulated emission light, a layer that includes a semiconductor that absorbs the stimulated emission light and emits spontaneous emission light, and a layer that absorbs the spontaneous emission light. A layer containing a phosphor in which a luminescent center is added to a matrix crystal arranged in a matrix so as to emit fluorescence of different wavelengths, and a light modulation means for modulating the light intensity of at least one of the spontaneous emission light and the fluorescence And is characterized by including.
[0014]
Note that the display device may further include a light guide for propagating the stimulated emission light and irradiating the semiconductor with at least a part of the light. Further, a semiconductor that absorbs stimulated emission light and emits spontaneous emission light may be in the form of particles or a plate. Thus, it is possible to obtain a display device in which the amount of light from the phosphor is less dependent on the environmental temperature.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
(Embodiment 1)
A lighting device according to a first embodiment of the present invention will be described with reference to FIGS. In the drawings of the present application, the same reference numerals represent the same or corresponding parts.
[0016]
In the lighting device shown in the schematic cross-sectional view of FIG. 1, a concave portion is formed at the tip of the left frame of the pair of lead frames 104. A GaN-based semiconductor laser device 100 that emits light having a wavelength of 400 nm is mounted on the bottom surface of the recess. A wiring 105 is connected between the upper surface of the GaN-based semiconductor laser device and the lead frame on the right side. The semiconductor laser device 100 absorbs the laser light and emits spontaneous emission light. _x Ga _1-x The dome of the first transparent acrylic resin 101 in which the N particles 102 are dispersed is covered. Here, this In _x Ga _1-x The mixed crystal ratio x of the N particles is set so as to absorb stimulated emission light having a wavelength of 400 nm emitted from the semiconductor laser device and emit spontaneous emission light having a wavelength of 430 nm serving as excitation light for the phosphor.
[0017]
Further, the dome of the first transparent acrylic resin 101 is red (Y ₂ O ₂ S: Eu ³⁺ ), Green (ZnS: Cu, Al) and blue ((Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) 6Cl ₂ : Eu ²⁺ 2) is covered with a dome of the second transparent acrylic resin 103 in which the phosphor is dispersed. Then, these phosphors are irradiated with excitation light and mixed with fluorescent light emitted from the phosphors, whereby a shell-type white lighting device can be obtained. Here, the parent crystal (Y ₂ O ₂ S) during the emission center (Eu ³⁺ In the case where a semiconductor laser element is used as a basic light source for a general phosphor to which a transition metal or the like is added, the schematic graph of FIG. 2 shows the environmental temperature dependence of the amount of fluorescence emitted from the phosphor. It will be described using FIG.
[0018]
The graph of FIG. 2 shows the relationship between the absorption spectrum of the phosphor and the oscillation spectrum of the semiconductor laser device that excites the phosphor. The horizontal axis of the graph indicates the wavelength (nm), the right vertical axis indicates the light intensity (arb .: arbitrary unit) of the semiconductor laser device, and the left vertical axis indicates the light absorption coefficient (%) of the phosphor. ing. In the graph, the solid curve (a) represents the oscillation spectrum of the semiconductor laser device, the arrow (b) represents the fluctuation range of the oscillation spectrum, and the dashed-dotted curve (c) represents the absorption spectrum of the phosphor. ing.
[0019]
Parent crystal (Y ₂ O ₂ ) During the emission center (Eu ³⁺ In the phosphor to which is added, a number of band structures are formed between the levels of the 4f electron orbital of the emission center and other orbitals. Due to such a band structure, the absorption spectrum of the phosphor has a shape having almost no flat region with respect to the wavelength as shown by the dashed line (c). Sex is almost nonexistent.
[0020]
On the other hand, the spectrum width of the oscillation wavelength of the semiconductor laser device is usually about several nm as shown by the solid line (a). The oscillation wavelength of the semiconductor laser device changes with a temperature dependency of about 0.3 to 0.5 nm / ° C. Therefore, in an environmental temperature range of 80 ° C. (−20 ° C. to 60 ° C.) in a general use state, the oscillation wavelength can change by about 30 to 40 nm.
[0021]
Due to such fluctuations in the oscillation wavelength of the semiconductor laser element, the amount of laser light absorbed by the phosphor as excitation light (corresponding to the integral of the overlap between the absorption spectrum of the phosphor and the oscillation spectrum of the semiconductor laser) decreases to about 20%. I can do it. As a result, the amount of fluorescence emitted from the phosphor also decreases to about 20% according to the amount of excitation light absorbed by the phosphor.
[0022]
On the other hand, the graph of FIG. 3 is similar to FIG. 2, but illustrates the operation and effect of the lighting device according to the first embodiment. That is, also in FIG. 3, the horizontal axis indicates the wavelength (nm), the right vertical axis indicates the light intensity (arb .: arbitrary unit) of the semiconductor laser device, and the left vertical axis indicates the absorption coefficient of the phosphor. (%). In the graph, the solid line curve (a) is the oscillation spectrum of the semiconductor laser, the one-dot chain line curve (c) is the absorption spectrum of the phosphor, and the two-dot chain line curve (d) is the spontaneous emission light emitted from the semiconductor. The spectrum and the arrow (e) represent the fluctuation range of the spectrum of the spontaneous emission emitted from the semiconductor.
[0023]
As can be seen from this graph, the laser light (a) from the semiconductor laser element is absorbed and In _x Ga _1-x The spectral width (e) of the spontaneous emission light (d) emitted from the N particles is much wider than the spectral width of the laser light. The spectrum width of the spontaneous emission light (d) is wider than the width of the absorption spectrum (c) of the phosphor. Therefore, even if the peak wavelength of the spontaneous emission light spectrum from a semiconductor that absorbs laser light changes depending on the environmental temperature, the amount of light absorbed by the phosphor changes by only about 10%. Fluctuations in the amount of emitted fluorescent light can be suppressed to a maximum of about 10%.
[0024]
That is, compared with the case where the laser light is directly absorbed by the phosphor as in the prior art illustrated in FIG. 2, the illumination device of the first embodiment shown in FIG. Then, the spontaneous emission light therefrom is absorbed by the phosphor, so that the environmental temperature dependency of the change in the amount of fluorescence from the phosphor can be remarkably reduced as illustrated in FIG.
[0025]
The semiconductor material that absorbs laser light and emits spontaneous emission light is In _x Ga _1-x The semiconductor is not limited to N, and may be any semiconductor having a band gap that emits light that the phosphor can absorb as excitation light, and a ZnMgSSe-based mixed crystal may be used. In addition, the illumination device may have a configuration in which a large number of the shell-shaped elements shown in FIG. 1 are arranged in an array, whereby a planar illumination device is obtained. In addition, a plurality of elements that emit light of a single color are arranged in a matrix by individually including phosphors that emit blue, green, and red fluorescent light, and a dimming unit that controls light emission intensity of each element is provided. Thus, a display device can be obtained.
[0026]
(Embodiment 2)
An example of the linear lighting device according to the second embodiment of the present invention is illustrated in the schematic perspective view of FIG. 4A and the corresponding schematic cross-sectional view of FIG. 4B. This lighting device comprises a polymethyl methacrylate core 400, a fluoropolymer cladding 401 covering the core, _x Ga _1-x A plastic fiber structure including a fluorine-based polymer layer 405 in which N semiconductor particles 403 are dispersed, and a fluorine-based polymer layer 402 which covers the polymer layer and in which phosphors emitting red, green, and blue fluorescent lights are dispersed; ing.
[0027]
A semiconductor laser device (not shown) is optically coupled to one end face of the plastic fiber. As the laser light incident on the plastic fiber propagates through the core 400 as indicated by the arrow in FIG. 4A, a part of the laser light is converted into an alumina provided on a part of the core 400. The light is scattered by the light scattering structure 404 including metal oxide particles. This scattered light is In _x Ga _1-x After being absorbed by the N semiconductor particles 403 and converted into spontaneous emission light, the light is emitted to the polymer layer 402 containing the phosphor. Then, white light is radiated out of the fiber as shown by the arrow in FIG. 4B due to the color mixture of the fluorescent light radiated from each phosphor.
[0028]
By installing such a fibrous light-emitting body, for example, on a ceiling in a room, a linear indoor lighting device can be realized.
[0029]
Another example of the linear lighting device according to the second embodiment is illustrated in the schematic perspective view of FIG. 5A and the schematic cross-sectional view of FIG. 5B corresponding thereto. This lighting device is _x Ga _1-x A polymethyl methacrylate core 400 containing N semiconductor particles 403, a fluoropolymer cladding 401 covering the core, and a fluoropolymer layer 402 covering the cladding and dispersing phosphors emitting red, green, and blue fluorescence. It has.
[0030]
Also in this lighting device, a semiconductor laser element (not shown) is optically coupled to one end face of the plastic fiber. As the laser light incident into the plastic fiber propagates through the core 400, a portion of the light _x Ga _1-x It is absorbed by the N semiconductor particles 403 and converted into spontaneous emission light and emitted. Then, the spontaneous emission light is applied to the phosphor-containing polymer layer 402, and white light due to the color mixture of the fluorescence emitted from each phosphor is emitted out of the fiber.
[0031]
In addition, In in FIG. _x Ga _1-x The N semiconductor particles 403 also have a function of a scattering structure for scattering spontaneous emission light emitted from the particles.
[0032]
The schematic sectional view of FIG. 6 illustrates still another example of the linear lighting device according to the second embodiment. This illuminating device includes a polymethyl methacrylate core 400 and a near-field light (evanescent light) region (shown by a broken line) in which a part of the propagating light seeps from the core. _x Ga _1-x The semiconductor device includes a fluoropolymer clad 401 in which N semiconductor particles 403 are dispersed, and a fluoropolymer layer 402 that covers the clad and contains a phosphor that emits red, green, and blue fluorescent light.
[0033]
In the case of FIG. 6, of the laser light propagating in the plastic fiber core 400, only a relatively small light component that seeps into the cladding 401 (in the area shown by the broken line) is In. _x Ga _1-x Interacts with N semiconductor particles. Therefore, In _x Ga _1-x Compared with the fiber of FIG. 5 in which the N semiconductor particles 403 are dispersed, the fiber of FIG. 6 can reduce the propagation loss of the laser light, and thus is suitable for a longer linear illumination device.
[0034]
By using the plastic fiber as in the second embodiment, it is possible to realize a linear lighting device in which the variation in the amount of fluorescent light emitted from the fluorescent material is less dependent on the environmental temperature. The type of fiber is not limited to plastic fiber, and quartz fiber or the like can be used.
[0035]
(Embodiment 3)
The schematic perspective view of FIG. 7 illustrates an example of the planar lighting device according to Embodiment 3 of the present invention. This lighting device is _x Ga _1-x A light guide 701 made of an acrylic resin plate in which N semiconductor particles 403 are dispersed and whose thickness changes in a tapered shape; a semiconductor laser element 700 joined to a thick side end surface of the light guide; An aluminum reflective film 702 for preventing the laser light and the spontaneous emission light from the semiconductor particles from being emitted and lost at the bottom surface of the light body, and the same phosphor as that of the first embodiment is dispersed on the upper surface of the light guide 701. Fluoropolymer layer 402 provided.
[0036]
In the lighting device of FIG. 7, as the laser light incident on the light guide 701 made of the acrylic resin propagates through the light guide, a part of the light is dispersed in the light guide. _x Ga _1-x It is absorbed by the N semiconductor particles 403. And this In _x Ga _1-x The spontaneous emission light from the N semiconductor particles is emitted to the phosphor-containing polymer layer 402, and white light due to the color mixture of the fluorescence emitted from each phosphor is emitted upward. Note that this In _x Ga _1-x The N semiconductor particles 403 are formed by laser light or In which propagates in the light guide 701. _x Ga _1-x It also has a function of scattering spontaneous emission light from N semiconductor particles.
[0037]
The schematic perspective view of FIG. 8 illustrates another example of the planar lighting device according to the third embodiment of the present invention. This illuminating device has a light guide 701 having a curved bottom surface and made of an acrylic resin plate having a continuously changing thickness, and a light guide that scatters a portion of light propagating in the light guide upward and emits light. An aluminum reflection film 702 provided on the bottom surface of the light guide so as to prevent the laser light from being emitted downward from the body and causing a loss, and an In film provided on the top surface of the light guide. _x Ga _1-x N semiconductor layer 800 and this In _x Ga _1-x A fluorine-based polymer layer 402 in which the same phosphor as that of the first embodiment is dispersed is provided on the N semiconductor layer. The semiconductor laser element 700 is optically coupled to the thicker side end face of the light guide 701.
[0038]
As the laser light incident on the light guide 701 made of acrylic resin propagates through the light guide, a part of the light is reflected by the aluminum reflection film 701 and becomes In. _x Ga _1-x The N semiconductor layer 800 is irradiated. This laser light is In _x Ga _1-x The phosphor-containing polymer layer 402 is absorbed by the N semiconductor layer, converted into spontaneous emission light, and irradiated to the phosphor-containing polymer layer 402. As a result, white light due to the color mixture of the fluorescent light emitted from each phosphor is emitted upward from the phosphor-containing polymer layer 402.
[0039]
As in the third embodiment, In _x Ga _1-x Even when an N semiconductor layer is used, In _x Ga _1-x As in the case where the N semiconductor particles are used, a planar illumination device in which the variation in the amount of fluorescent light emitted from the phosphor is less dependent on environmental temperature can be obtained.
[0040]
(Embodiment 4)
The schematic perspective view of FIG. 9 illustrates a planar lighting device according to Embodiment 4 of the present invention. This lighting device includes a light guide including a waveguide structure including an epoxy resin core layer 901 and epoxy resin clads 900 and 902 sandwiching the core layer and having a different refractive index from the core. In this light guide, the light component in the vertical direction is confined inside the core layer by the refractive index distribution formed by the core layer 901 and the cladding layers 900 and 901. An aluminum reflective film 702 is provided on the bottom surface of the lower cladding layer 900 to prevent laser light from being emitted from the light guide portion and causing loss. On the top surface of the light guide, In _x Ga _1-x An N semiconductor layer 703 and a fluorine-based polymer layer 402 in which a phosphor similar to that of the first embodiment is dispersed are provided thereon. The semiconductor laser device 700 is optically coupled to the core layer 901 at one end face of the light guide.
[0041]
As the laser light incident on the core 901 in the light guide made of epoxy resin propagates through the core, a part of the light is caused by the refractive index distribution due to the uneven shape provided on the lower surface of the core. _x Ga _1-x The N semiconductor layer 703 is irradiated. And this laser light is In _x Ga _1-x The light is absorbed by the N semiconductor layer 703, converted into spontaneous emission light, and emitted. The spontaneous emission light is applied to the phosphor-containing polymer layer 402, and white light due to the color mixture of the fluorescence emitted from each phosphor is emitted upward.
[0042]
Also in the fourth embodiment, for the same reason as in the first embodiment, it is possible to obtain a planar lighting device in which the variation in the amount of fluorescent light emitted from the phosphor is less dependent on the environmental temperature.
[0043]
Note that the waveguide structure included in the light guide according to the fourth embodiment is not limited to the three-layer slab structure, and various structures can be used. In addition, by dispersing InGaN particles in the core, a lighting device including a waveguide structure in which laser light propagating in the core is absorbed by the InGaN particles and converted into spontaneous emission light may be manufactured. It is possible.
[0044]
(Embodiment 5)
10 and 11 schematically illustrate a display device according to Embodiment 5 of the present invention. FIG. 10A is a cross-sectional view of the display device, FIG. 10B is a top view of an optical fiber included therein, and FIG. 11 is a cross-sectional view of the fiber. In this display device, a plastic fiber 1000 having a semiconductor laser element 700 connected at one end includes a core 400 through which laser light propagates and a clad 401 covering the core 400, and light exudes into the clad in a propagating light component. In the region (shown by a broken line) _x Ga _1-x N semiconductor particles 403 are dispersed. The plastic fiber is arranged as shown in FIGS. 10A and 10B, and is fixed to the housing by the base 1003.
[0045]
The laser light propagating through such a plastic fiber 1000 is reflected by this In _x Ga _1-x N semiconductor particles 403 absorb this In _x Ga _1-x Spontaneous emission light from the N semiconductor particles 403 is emitted as excitation light of the phosphor. Then, as shown in FIG. 10A, the active matrix drive type sandwiched between the polarizing plates is controlled so that the light intensity of the excitation light emitted from the plastic fiber 1000 is controlled corresponding to each pixel. A liquid crystal light modulation element layer 1001 including a TFT (thin film transistor) is provided.
[0046]
Further, on the liquid crystal light modulation element layer 1001, phosphors 1002 that emit red, green, and blue fluorescent light similar to those of the first embodiment are arranged in a pixel shape corresponding to each pixel. The display device is operated by controlling the light intensity of the excitation light applied to each of the red, green, and blue phosphors by the liquid crystal light modulation element layer 1001 in this manner. With the configuration of the fifth embodiment, for the same reason as in the first embodiment, it is possible to obtain a display device in which the variation in the amount of fluorescence emitted from the phosphor is less dependent on the environmental temperature.
[0047]
(Embodiment 6)
FIG. 12 is a schematic perspective view illustrating an example of a display device according to Embodiment 6 of the present invention. This display device has a light guide shown in FIG. 7 of the third embodiment and In on the light guide. _x Ga _1-x A liquid crystal light modulation element layer 1001 including an active matrix driving type TFT (thin film transistor) sandwiched between polarizing plates so as to control the light intensity of the excitation light emitted from the N semiconductor particles corresponding to each pixel. . Further, on the liquid crystal light modulation element layer 1001, phosphors 1002 that emit red, green, and blue fluorescent light similar to those of the first embodiment are arranged in a pixel shape corresponding to each pixel. The semiconductor laser element 700 is optically coupled to the thicker side end face of the light guide 701.
[0048]
FIG. 13 illustrates another example of the display device according to Embodiment 6 of the present invention in a schematic perspective view. In this display device, In provided on the upper surface of the light guide including the optical waveguide structure of the fourth embodiment. _x Ga _1-x N semiconductor layer 703 and this In _x Ga _1-x A liquid crystal light modulation element layer 1001 including an active matrix drive type TFT (thin film transistor) sandwiched between polarizing plates is provided so as to control the intensity of spontaneous emission light from the N semiconductor film corresponding to each pixel. Further, on the liquid crystal light modulation element layer 1001, phosphors 1002 that emit red, green, and blue fluorescent light similar to those of the first embodiment are arranged in a pixel shape corresponding to each pixel. The semiconductor laser device 700 is optically coupled to the core layer 901 at the end face of the light guide.
[0049]
As described above, the display device can be operated by controlling the light intensity of the excitation light applied to each of the red, green, and blue phosphors by the liquid crystal light modulation element layer 1001. Also, according to the configuration of the sixth embodiment, it is possible to obtain a display device in which the variation in the amount of fluorescence from the phosphor is less dependent on the environmental temperature for the same reason as in the first embodiment.
[0050]
Note that the optically disposed portion of the liquid crystal light modulation element layer 1001 is In as in this embodiment. _x Ga _1-x Not limited to between the N semiconductor layer 703 and the phosphor layer 1002, the upper cladding 902 and the In _x Ga _1-x It may be provided between the N semiconductor layer 703 and the phosphor layer 1002.
[0051]
(Embodiment 7)
FIG. 14 illustrates a display device according to Embodiment 7 of the present invention in a schematic sectional view. This display device includes an acrylic resin layer 1002 in which respective phosphors emitting red, green, and blue fluorescent light arranged in a pixel shape corresponding to each pixel are individually dispersed, and these individual phosphors are provided. Are provided. Further, In between the phosphor 1002 and the semiconductor laser element 700, In _x Ga _1-x An acrylic resin layer 703 in which N semiconductor particles are dispersed is arranged. A control circuit 1400 is provided to modulate the injection current of these semiconductor laser elements 700.
[0052]
Thus, In _x Ga _1-x The control circuit 1400 directly controls the amount of light of the semiconductor laser element 700 irradiated to the N semiconductor particles, _x Ga _1-x The display device can be operated by controlling the light intensity of the excitation light emitted from the N semiconductor particles to each of the red, green, and blue phosphors. Further, with the configuration of the seventh embodiment, it is possible to obtain a display device in which the variation in the amount of fluorescence from the phosphor is less dependent on the environmental temperature for the same reason as in the first embodiment.
[0053]
The semiconductor laser element 700 can be either an edge emitting type or a vertical cavity type. However, in the display device according to the seventh embodiment, a vertical resonance type laser element that emits light in the vertical direction is used. More preferred.
[0054]
【The invention's effect】
As described above, according to the present invention, in a lighting device and a display device using a semiconductor laser element and a phosphor, the amount of fluorescence from the phosphor caused by the resonance wavelength fluctuation of the semiconductor laser element caused by the environmental temperature fluctuation is reduced. Can be suppressed.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a lighting device according to a first embodiment of the present invention.
FIG. 2 is a schematic graph showing a relationship between an oscillation spectrum of a semiconductor laser and an absorption spectrum of a phosphor when the semiconductor laser is used as a basic light source.
FIG. 3 shows the relationship between the emission spectrum of InGaN and the absorption spectrum of the phosphor when the stimulated emission light from the semiconductor laser is absorbed by InGaN and the spontaneous emission emitted from InGaN is used as the excitation light source of the phosphor. It is a schematic graph.
4A is a schematic perspective view illustrating an example of a lighting device according to Embodiment 2 of the present invention, and FIG. 4B is a schematic cross-sectional view corresponding to FIG.
5A is a schematic perspective view showing another example of the illumination device according to Embodiment 2 of the present invention, and FIG. 5B is a schematic sectional view corresponding to FIG.
FIG. 6 is a schematic sectional view showing still another example of the lighting device according to the second embodiment of the present invention.
FIG. 7 is a schematic perspective view showing an example of a lighting device according to Embodiment 3 of the present invention.
FIG. 8 is a schematic perspective view showing another example of the lighting device according to Embodiment 3 of the present invention.
FIG. 9 is a schematic perspective view showing a lighting device according to Embodiment 4 of the present invention.
FIG. 10A is a schematic cross-sectional view illustrating a lighting device according to Embodiment 5 of the present invention, and FIG. 10B is a schematic plan view illustrating a fiber included in FIG.
FIG. 11 is a schematic cross-sectional view of the optical fiber in FIG.
FIG. 12 is a schematic perspective view showing an example of a display device according to Embodiment 6 of the present invention.
FIG. 13 is a schematic perspective view showing another example of the display device according to Embodiment 6 of the present invention.
FIG. 14 is a schematic sectional view showing a display device according to Embodiment 7 of the present invention.
[Explanation of symbols]
Reference Signs List 100 semiconductor laser element, 101 acrylic resin, 102 In _x Ga _1-x NN particles, 103 acrylic resin containing phosphor, 104 lead frame, 105 wiring, 400 core, 401 clad, 402 fluoropolymer part, 403 In _x Ga _1-x N semiconductor particles, 404 light scattering structure, 405 fluorine-based polymer part, 700 semiconductor laser element, 701 light guide, 702 aluminum reflective film, 800 In _x Ga _1-x N semiconductor film, 900, 902 clad, 901 core, 1000 plastic fiber, 1001 liquid crystal light modulator, 1002
Acrylic resin containing phosphor, 1003 pedestal, 1400 circuits.

Claims (7)

A semiconductor laser device that emits stimulated emission light,
A layer containing a semiconductor that absorbs the stimulated emission light and emits spontaneous emission light,
A layer containing a phosphor in which an emission center is added to a base crystal so as to absorb the spontaneous emission light and emit fluorescence of a different wavelength. The semiconductor laser device is mounted on a frame, the semiconductor is included in a first cap material covering the semiconductor laser device, and the phosphor is a second cap covering the first cap material. The lighting device according to claim 1, wherein the lighting device is included in a material. The lighting device according to claim 1, further comprising a light guide that propagates the stimulated emission light and irradiates the semiconductor with at least a part of the light. The lighting device according to claim 1, wherein the semiconductor has a particle shape or a plate shape. A semiconductor laser device that emits stimulated emission light,
A layer containing a semiconductor that absorbs the stimulated emission light and emits spontaneous emission light,
A layer containing a phosphor to which a luminescent center is added to a host crystal arranged in a matrix so as to absorb the spontaneous emission light and emit fluorescence of a different wavelength,
A display device comprising: a light modulating unit that modulates the intensity of at least one of the spontaneous emission light and the fluorescence. The display device according to claim 5, further comprising a light guide that propagates the stimulated emission light and irradiates the semiconductor with at least a part of the light. The display device according to claim 5, wherein the semiconductor is in a particle shape or a plate shape.

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