JP2007180415A - Light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device available as a general illuminating light source that uses a semiconductor laser chip, by enhancing a radiation property of light emitted from the semiconductor laser chip so as to be spread uniformly. <P>SOLUTION: Scattered light, emitted from a semiconductor chip and having a predetermined wavelength and an elliptical cross section, is converted into a light of a wavelength that is different from the predetermined wavelength by a wavelength converting member, after adjusting the cross-sectional shape of the scattered light using the arrangement of at least one of a barrel-like lens and a planar concave lens. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

The following two inventions are listed as conventional techniques related to this invention.
Each of these conventional technologies is a technology related to a light emitting device that emits white light by using a light emitted from a semiconductor light emitting element as excitation light to generate light having a long wavelength.
Japanese Patent No. 2927279 JP 2004-140185 A

  In recent years, light-emitting devices using LEDs have begun to be used as light-emitting devices that replace conventional light bulbs in display of traffic lights and instrument panels, and are also being used in lighting equipment for general households.

However, it is difficult for the LED chip to obtain an output larger than this in the range of several mW to about 10 mW. On the other hand, the semiconductor laser chip can obtain a large output of 30 mW to 10 W compared with the LED chip.
While the semiconductor laser chip has the advantage of high output, the light radiation pattern is narrower in the direction parallel to the active layer and narrower in the direction perpendicular to the active layer. There was a problem that occurred.

  The present invention has been made in consideration of the above-described circumstances. By improving the radiation characteristics of light emitted from a semiconductor laser chip so as to spread uniformly, a general semiconductor laser chip is used. A light-emitting device that can be used as a light source for illumination is provided.

  The present invention provides a semiconductor laser chip that emits diffused light having a predetermined wavelength and an elliptical cross section, a lens that adjusts the cross-sectional shape of the diffused light, and receives light that has been adjusted into light having a wavelength different from the predetermined wavelength. A wavelength conversion member that converts and emits at least, and the lens is disposed so as to shorten the major axis of the cross section of the diffused light, and is disposed so as to increase the minor axis of the cross section of the diffused light. The present invention provides a light emitting device characterized by being at least one of plano-concave lenses.

  According to the present invention, the wavelength conversion member is obtained by adjusting the cross-sectional shape of the diffused light emitted from the semiconductor laser chip and having an elliptical cross section at a predetermined wavelength by adjusting at least one of the kamaboko lens and the plano-concave lens. Therefore, it is possible to improve the radiation characteristic of the light emitted from the semiconductor laser chip so as to spread evenly.

  A light-emitting device according to the present invention has a semiconductor laser chip that emits diffused light having a predetermined wavelength and an elliptical cross section, a lens that adjusts the cross-sectional shape of the diffused light, and the adjusted light that is different from the predetermined wavelength At least a wavelength conversion member that converts the light into a wavelength and emits the light, and the lens is arranged so as to shorten the long diameter of the cross section of the diffused light, and the short diameter of the cross section of the diffused light is increased. It is characterized by being at least one of the plano-concave lenses arrange | positioned in this way.

In the light emitting device according to the present invention, the semiconductor laser chip uses the electroluminescence (EL) effect in the light emission principle, and resonates light generated when a voltage is applied in the forward direction by a cleavage plane or the like to generate laser oscillation. Any semiconductor may be used. The semiconductor structure is not particularly limited, and examples thereof include a PN junction, a double hetero structure, and a quantum well structure.

The lens is not particularly limited as long as it can adjust the diffused light having an elliptical cross section, and examples thereof include a kamaboko lens and a plano-concave lens.
The kamaboko lens indicates a convex cylindrical lens having a kamaboko shape, and the plano-concave lens indicates a concave cylindrical lens.

The wavelength conversion member is not particularly limited as long as it is a member containing a substance that generates light having a wavelength different from that of light received as excitation light. For example, a substance such as a phosphor May be kneaded or coated light-transmitting members.
The wavelength conversion member may generate light having a wavelength different from the emission wavelength of the semiconductor laser chip, which is excitation light, using light emitted from the semiconductor laser chip as excitation light, and the generated light is coherence like laser light. It is not necessary to have. The wavelength conversion member may have a function of reducing the coherence of the laser light emitted from the semiconductor laser chip.
For example, the wavelength conversion member may be applied to a window member of a package that hermetically seals the semiconductor laser chip, or may be kneaded to the window member.
The light emitting device according to the present invention may include a member other than the semiconductor laser chip, the lens, and the wavelength conversion member.

In the light emitting device according to the present invention, the lens may be a kamaboko type lens that approximates a diffused light section to a circle.
According to such a configuration, the major axis of the elliptical diffused light emitted from the semiconductor laser chip can be shortened to approximate the cross section of the diffused light to a circle.

In the light emitting device according to the present invention, the lens may be a plano-concave lens that approximates a circular cross section of the diffused light.
According to such a configuration, the minor axis of the elliptical diffused light emitted from the semiconductor laser chip can be lengthened, and the cross section of the diffused light can be approximated to a circle.

In the light emitting device according to the present invention, the semiconductor laser chip has a P-type electrode and an N-type electrode, and is parallel to the PN junction surface and emits purple to blue laser light in two opposite directions. A light emitting laser chip may be used.
Here, the purple to blue laser light includes, for example, laser light having a wavelength of 320 to 480 nm.
The material and the junction structure of the semiconductor laser chip are not particularly limited as long as the laser beam having the above wavelength can be emitted. Examples of the material include gallium nitride (GaN) and indium gallium nitride. (InGaN) etc. are mentioned, As a junction structure, a double hetero coupling, a quantum well type, etc. are mentioned.

In the light emitting device according to the present invention, the semiconductor laser chip has two end faces for emitting laser light, of which the end face reflectance on the side facing the wavelength conversion member is set to 20% or less, and the end face reflectance on the opposite side is set. May be set to 60% or more.
According to such a configuration, the laser light output on the wavelength conversion member side can be further increased, and a brighter light emitting device can be manufactured.
Here, the end face reflectivity includes the reflectivity of the cleavage plane of the semiconductor laser chip. The reflectance can be adjusted by the material and thickness of the coating material and the multilayer structure of a plurality of materials.

In the light emitting device according to the present invention, the wavelength conversion member may be excited by laser light emitted from the semiconductor laser chip and generate light having a wavelength longer than the wavelength of the laser light.
According to such a configuration, the wavelength conversion member excited by the purple to blue laser light is, for example, light having a wavelength longer than the wavelength of the laser light, such as yellow, green, blue, or red, depending on the material used for the member. Can be issued.

In this case, the substance used for the wavelength conversion member includes a base, an activator, and a flux.
The substrate is, for example, an oxide such as a rare earth element such as zinc, cadmium, magnesium, silicon, yttrium, an inorganic phosphor such as sulfide, silicate, vanadate, or fluorescein, eosin, oils (mineral oil) Are selected from organic phosphors.
The activator is selected from, for example, silver, copper, manganese, chromium, eurobium, zinc, aluminum, lead, phosphorus, arsenic, gold and the like.
The flux is selected from, for example, sodium chloride, potassium chloride, magnesium carbonate, barium chloride and the like.

In the light emitting device according to the present invention, the wavelength conversion member may be excited by laser light emitted from the semiconductor laser chip to generate white visible light.
According to such a configuration, it becomes possible to manufacture a light emitting device that emits white light using a semiconductor laser chip.

Here, the phosphor used in the wavelength conversion member that emits white light when excited by the laser light is not particularly limited. For example, a YAG (yttrium, aluminum, garnet) activated by cerium is used. A yellow phosphor, specifically Y ₃ Al ₅ O ₁₂ : Ce, Y ₃ (Al _0.6 Ga _0.4 ) ₅ O ₁₂ : Ce or Y ₃ (Al _0.5 Ga _0.5 ) ₅ O ₁₂ : Ce. .

Further, according to the present invention, a plurality of light emitting devices are arranged in a straight line or a lattice at equal intervals so that light is emitted in a certain direction, covered with a light transmissive protective plate, and diffused with respect to the light transmissive protective plate. Provided are illumination light sources adjacent to each other so that the light irradiation areas are in contact with each other.
According to such a configuration, a plurality of light emitting devices in which the diffused light emission angle is adjusted by approximating the cross section of the diffused light to a circular shape by a kamaboko lens or a plano-concave lens are arranged in a straight line or a lattice pattern. This makes it possible to produce a light source that is brighter and has less light emission unevenness on a wider surface.
In the illumination light source according to the present invention, the light-transmitting protective plate is not particularly limited in terms of material, color, etc. as long as it covers a plurality of light emitting devices and transmits light.

In the illumination light source according to the present invention, a plurality of adjacent light emitting devices may be closely arranged.
According to such a configuration, a light source having a brighter light emitting surface can be manufactured.
Note that the close arrangement here means not only an arrangement in which a plurality of adjacent light-emitting devices are in contact with each other, but also an arrangement close to the extent that they are not in physical and electrical contact.

In addition, the present invention receives a plurality of semiconductor laser chips that emit diffused light having a predetermined wavelength and an elliptical cross section, and receives the diffused light emitted from the plurality of semiconductor laser chips and converts the light to a wavelength different from the predetermined wavelength. The semiconductor laser chips are arranged in a single row or in a plurality of parallel rows, the irradiation regions with respect to the wavelength conversion member are in contact with each other, and the short diameter portion of the irradiation region is straight. An illumination light source arranged continuously on a line is provided.
According to such a configuration, since the laser light emitted from the plurality of semiconductor laser chips is received by the common wavelength conversion member, a surface light source with less light emission unevenness can be manufactured.

In the illumination light source according to the present invention, a plurality of semiconductor laser chips may be arranged in a lattice pattern.
According to such a configuration, a surface light source with little light emission unevenness can be efficiently manufactured.

In the illumination light source according to the present invention, the semiconductor laser chip emits purple to blue laser light, and the wavelength conversion member is excited by the purple to blue laser light to generate long-wavelength light. It may be emitted.
According to such a configuration, the common wavelength conversion member is excited by the violet to blue laser light emitted from the plurality of semiconductor laser chips and emits white visible light in a wide range, so there is little emission unevenness. A white light source with a large area can be manufactured and has many possibilities.

  Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Example 1
FIG. 1 is a perspective view showing an appearance of a semiconductor laser light emitting device according to the first embodiment. FIG. 2 is a diagram showing a part cut out from the perspective view of FIG. 1 for explaining the structure of the semiconductor laser light emitting device according to the first embodiment.

As shown in FIG. 2, in the semiconductor laser light emitting device 100, the semiconductor laser chip 1 has a P-type electrode connected to a lead pin 7 with a metal wire 10, and an N-type electrode connected to a common via a submount 5, a metal wire 10 and a stem 12. The lead pin 8 is electrically connected.
In the photodiode chip 6, the N-type electrode is electrically connected to the other lead pin 7 by the metal wire 10, and the P-type electrode is electrically connected to the common lead pin 8 through the stem 12.
The two lead pins 7 are bonded to the semiconductor laser light emitting device 100 via an insulating hermetic glass 9 so as not to be directly electrically connected to the stem 12.
A kamaboko lens 2 is placed on the laser beam emitting side of the semiconductor laser chip 1.
The semiconductor laser chip 1, the kamaboko type lens 2, the photo die auto chip 6, and the like are hermetically sealed by a can 11 and a stem 12 provided with a light-transmitting protective plate 3.
A fluorescent layer 4 is formed on the light-transmissive protective plate 3.
The light-transmitting protective plate 3 is bonded to the can 11 via an insulating hermetic glass 9.
The hermetic glass 9 also has a function of keeping hermeticity in the package.

In the semiconductor laser chip 1, the surface on which the kamaboko lens 2 is placed and the opposite surface are cleaved surfaces, and laser light is emitted from the active layers of the two cleaved surfaces.
The semiconductor laser chip 1 emits violet to blue laser light having a wavelength of 320 nm to 480 nm.
With respect to the chip end face which oscillates, the reflectivity of the end face on which the kamaboko lens 2 is placed is lowered to 20% or less, and the opposite side is raised to 60% or more so that the kamaboko lens 2 is placed. The effective radiation power of the placed end face is strengthened.
In order to detect the output of the semiconductor laser chip 1, the photodiode chip 6 is installed on an extension line of the end surface of the semiconductor laser chip 1 opposite to the side on which the kamaboko lens 2 is placed.

The radiation pattern of the laser light emitted from the semiconductor laser chip 1 is diffused light having an elliptical cross-sectional shape, and is greatly spread in the vertical direction with respect to the active layer, and is also in the horizontal direction with respect to the active layer. The way of spreading is getting smaller.
Although not shown, the active layer is a layer that forms the semiconductor laser chip 1, and is a layer parallel to the surface where the semiconductor laser chip 1 and the metal wire 10 are connected and the surface that is in contact with the submount 5. It is. Laser oscillation is performed in the active layer.
When used as a light source for illumination, it is desirable that the diffused light spreads in a circular shape. Therefore, by placing a kamaboko type lens (convex cylindrical lens) 2 on the laser light emitting surface of the semiconductor laser chip 1 and refracting the laser light spreading in the direction perpendicular to the active layer to shorten the long diameter portion of the cross-sectional shape. The diffuse light is approximated to a circle.

The laser beam whose cross-sectional shape approximates a circle by the kamaboko lens 2 is wavelength-converted by the fluorescent layer 4 and is emitted to the outside as visible light.
The fluorescent layer is a YAG (yttrium, aluminum, garnet) yellow phosphor activated by cerium, specifically Y ₃ Al ₅ O ₁₂ : Ce, Y ₃ (Al _0.6 Ga _0.4 ) ₅ O ₁₂ : Ce. Alternatively, Y ₃ (Al _0.5 Ga _0.5 ) ₅ O ₁₂ : Ce or the like is used.
The fluorescent layer 4 generates violet or blue laser light emitted from the semiconductor laser chip 1 as excitation light and generates yellow light having a longer wavelength than the excitation light. The light generated by the fluorescent layer 4 has no coherence.
The coherence of the violet to blue laser light is reduced by the phosphor of the fluorescent layer 4, and as a result, the fluorescent layer 4 emits white visible light.
As described above, the purple to blue laser light emitted from the semiconductor laser chip 1 is radiated to the fluorescent layer 4 formed on the light-transmissive protective plate 3 after the cross-sectional shape of the diffused light is adjusted by the kamaboko lens 2. As a result, white light whose cross-sectional shape approximates a circle is emitted to the outside. This makes it possible to manufacture a light-emitting device suitable for use as an illumination light source.

(Example 2)
FIG. 1 is a perspective view showing an appearance of a semiconductor laser light emitting device according to a second embodiment. FIG. 3 is a diagram showing a part cut out from the perspective view of FIG. 1 for explaining the structure of the semiconductor laser light emitting device according to the second embodiment. The semiconductor laser light emitting device of Example 2 is the same as that of Example 1 in appearance.

As shown in FIG. 3, in the semiconductor laser light emitting device 200, the semiconductor laser chip 1 has a P-type electrode connected to the lead pin 7 by the metal wire 10, and an N-type electrode connected to the common via the submount 5, the metal wire 10 and the stem 12. The lead pin 8 is electrically connected.
In the photodiode chip 6, the N-type electrode is electrically connected to the other lead pin 7 by the metal wire 10, and the P-type electrode is electrically connected to the common lead pin 8 through the stem 12.
The two lead pins 7 are bonded to the semiconductor laser light emitting device 200 through an insulating hermetic glass 9 so as not to be directly electrically connected to the stem 12.
A plano-concave lens 13 is placed on the laser light emitting side of the semiconductor laser chip 1.
The semiconductor laser chip 1, the plano-concave lens 13, the photo die auto chip 6 and the like are hermetically sealed by a can 11 and a stem 12 provided with a light-transmitting protective plate 3.
A fluorescent layer 4 is formed on the light-transmissive protective plate 3.
The light-transmitting protective plate 3 is bonded to the can 11 via an insulating hermetic glass 9.

The structural difference between the second embodiment and the first embodiment described above is that the kamaboko lens 2 placed on the semiconductor laser chip 1 in the first embodiment is a plano-concave lens (concave cylindrical lens) 13 in the second embodiment. It was only replaced with.
The diffused light having an elliptical cross-sectional shape emitted from the semiconductor laser chip 1 is refracted by the plano-concave lens 13 placed on the laser light emitting surface of the semiconductor laser chip 1, and the short axis of the cross-sectional shape becomes long. The cross-sectional shape approximates a circle.
Except for the above, the diffused light whose cross-sectional shape is adjusted so as to approximate a circular shape by the plano-concave lens 13 is radiated to the fluorescent layer 4 formed on the light-transmitting protective plate 3, as in Example 1. White light whose cross-sectional shape approximates a circle is emitted to the outside. This makes it possible to manufacture a light-emitting device suitable for use as an illumination light source.

Further, a modified example in which a plano-concave lens and a kamaboko type lens are combined will be described with reference to FIG.
FIG. 14 is a diagram for explaining an example in which the kamaboko lens 2a is placed on the concave side of the plano-concave lens 13a. FIG. 14 is a diagram for explaining the arrangement of the plano-concave lens 13a and the kamaboko lens 2a on the semiconductor laser chip 1, and the other portions are not shown.

In the case of the kamaboko type lens 2 according to the first embodiment only, the long diameter portion cannot be shortened to such an extent that the cross sectional shape of the diffused light is approximated to a circle. When the short diameter portion cannot be made long enough to approximate the circle, the plano-concave lens 13a and the kamaboko lens 2a are combined and placed on the light emitting surface of the semiconductor laser chip 1 as shown in FIG.
By combining the plano-concave lens 13a and the kamaboko type lens 2a, it becomes possible to adjust both the long diameter part and the short diameter part of the elliptical diffused light emitted from the semiconductor laser chip 1, and approximate the diffused light to a circular shape. There are plenty of options for making it happen.
In the modification shown in FIG. 14, the kamaboko lens 2a and the plano-concave lens 13a may be lenses having different refractive indexes from those of the kamaboko lens 2 and the plano-concave lens 13 used in the first and second embodiments.

(Example 3)
FIG. 4 is a view showing an illumination light source constituted by the semiconductor laser light emitting device 100 of the first embodiment and the like from the light emitting surface side according to the third embodiment. FIG. 5 is a side view of the illumination light source according to the third embodiment. FIG. 6 is a view showing a cross-sectional shape of light emitted from the plurality of semiconductor laser light emitting devices 100 of FIG. 4 to the light-transmissive protective plate.

  As shown in FIG. 4, the illumination light source 300 includes a plurality of semiconductor laser light emitting devices 100 according to the first embodiment arranged in a lattice pattern, and a light-transmissive protective plate 14 that covers the plurality of semiconductor laser light emitting devices 100. Etc. (components other than the above are not shown). Further, as shown in the side view of FIG. 5, each semiconductor laser light emitting device 100 is arranged on the substrate 19 without tilting so that light is emitted in a certain direction.

Each semiconductor laser light emitting device 100 shown in FIG. 4 shows the semiconductor laser light emitting device 100 shown in FIG. 1 as viewed from the light emitting surface side. The fluorescent layer 4, the light-transmitting protective plate 3, the metal wire 10 and the like are omitted so as to make it easy to grasp the angles at which they are arranged.
The light-transmitting protection plate 14 may be any light-transmitting plate, and the material, color, etc. are not particularly limited.

As shown in FIG. 6, the diffused light emitted from the plurality of semiconductor laser light emitting devices 100 arranged in a lattice shape to the light-transmissive protective plate 14 has a cross-sectional shape that approximates a circle and is adjacent to each other. The matching sections are arranged so as to be close to each other. By arranging a plurality of semiconductor laser light emitting devices 100 in a lattice shape in this way, it is possible to manufacture an illumination light source with little emission unevenness.
Since each semiconductor laser light emitting device 100 is adjusted by the kamaboko lens 2 so that the cross-sectional shape of the diffused light approximates a circle, it is only necessary to arrange them at the same interval. As shown in FIG. The apparatus 100 does not have to be arranged so that the internal semiconductor laser chip 1 is parallel when viewed from the light emitting surface side.

In the illumination light source 300 according to the third embodiment, the semiconductor laser light emitting device 200 according to the second embodiment may be used instead of the semiconductor laser light emitting device 100.
In this case, since the diameter of the cross section of the diffused light that approximates a circle is larger than the diameter of the diffused light of the semiconductor laser light emitting device 100, the intervals at which the semiconductor laser light emitting devices 200 are arranged are each semiconductor laser light emitting device in FIG. It may be wider than 100 intervals.

Example 4
FIG. 7 is a view showing an illumination light source constituted by the semiconductor laser light emitting device 100 of Example 1 from the light emitting surface side according to Example 4. FIG.

  As illustrated in FIG. 7, the illumination light source 400 includes a plurality of semiconductor laser light emitting devices 100 according to the first embodiment arranged in a lattice pattern, and a light-transmissive protective plate 15 that covers the plurality of semiconductor laser light emitting devices 100. Etc. (components other than the above are not shown).

The illumination light source 400 of the fourth embodiment is an illumination light source in which a plurality of semiconductor laser light emitting devices 100 arranged in a grid pattern in the illumination light source 300 of the above-described third embodiment are brought close to each other to the extent that they are not physically contacted. It is.
As shown in FIG. 7, by bringing a plurality of semiconductor laser light emitting devices 100 closer to each other, it is possible to manufacture a bright illumination light source with less emission unevenness.
Each semiconductor laser light emitting device 100 is adjusted so that the cross-sectional shape of the diffused light approximates a circular shape by the kamaboko type lens, so it is only necessary to arrange them at the same interval. As shown in FIG. 100 need not be arranged at the same angle so that the internal semiconductor laser chip 1 is parallel when viewed from the light emitting surface side.

  In the illumination light source 400 according to the fourth embodiment, the semiconductor laser light emitting device 200 according to the second embodiment may be used instead of the semiconductor laser light emitting device 100.

(Example 5)
FIG. 8 is a diagram showing an illumination light source from the light emitting surface side according to the fifth embodiment. FIG. 9 is a diagram showing a cross-sectional shape of light emitted from the plurality of semiconductor laser devices of FIG. 8 to the light-transmissive protective plate.

As shown in FIG. 8, in the illumination light source 600, a plurality of semiconductor laser devices 500 having a structure in which the kamaboko lens 2 and the fluorescent layer 4 are removed from the structure of the semiconductor laser illuminating device 100 in the first embodiment are arranged in a line at equal intervals. And a light-transmitting protective plate 16 covering the plurality of semiconductor laser devices 500 (other components are not shown).
The light-transmitting protective plate 16 is provided with a uniform fluorescent layer over the entire surface (the fluorescent layer is not shown).

Each semiconductor laser device 500 shows a state in which the kamaboko lens 2 and the fluorescent layer 4 are removed from the semiconductor laser light emitting device 100 shown in the perspective view of FIG. It should be noted that the light-transmitting protective plate 3 and the metal wire 10 are omitted so as to make it easier to grasp the angle at which each is disposed.
The semiconductor laser device 500 emits purple or blue laser light to the outside.
The fluorescent layer provided on the light-transmitting protection plate 16 generates yellow light having a wavelength longer than that of the excitation light using the purple to blue laser light emitted from the semiconductor laser device 500 as the excitation light. The light generated by the fluorescent layer has no coherence. The coherence of the violet to blue laser light is reduced by the phosphor in the phosphor layer. As a result, the light-transmissive protective plate 16 provided with the fluorescent layer emits white visible light.

The laser light emitted from the semiconductor laser device 500 to the light-transmissive protective plate 16 has an elliptical cross-sectional shape that is long in the vertical direction with respect to the active layer and short in the parallel direction.
The semiconductor laser device 500 having such radiation characteristics is arranged so that the minor axis portions of the cross-sectional shape are continuously arranged in a straight line as shown in FIG. White visible light with little emission unevenness is emitted from the layer.
As described above, it is possible to manufacture an illumination light source that can radiate widely in the vertical direction of a column and has little unevenness of light emission using the difference between the lengths of the major axis portion and the minor axis portion of the cross-sectional shape.

(Example 6)
FIG. 10 is a view showing an illumination light source from the light emitting surface side according to the sixth embodiment. FIG. 11 is a view showing a cross-sectional shape of light emitted from the plurality of semiconductor laser devices of FIG. 10 to the light-transmitting protective plate.

As shown in FIG. 10, the illumination light source 700 includes the semiconductor laser devices 500 arranged in a row in Example 5 arranged in a plurality of parallel rows, and the light-transmissive protective plate 17 covering the plurality of semiconductor laser devices 500. Etc. (components other than the above are not shown).
The light-transmitting protective plate 17 is provided with a uniform fluorescent layer over the entire surface (the fluorescent layer is not shown).

The laser light emitted from the semiconductor laser device 500 to the light-transmissive protective plate 17 has an elliptical cross-sectional shape that is long in the vertical direction and short in the parallel direction with respect to the active layer.
The semiconductor laser devices 500 having such radiation characteristics are configured in a plurality of parallel rows, and the cross-sectional shapes with respect to the light-transmissive protective plate 17 are in contact with each other as shown in FIG. By arranging the short-diameter portions of the shape so as to be continuously arranged in a straight line, white visible light with little uneven emission is emitted from the fluorescent layer provided on the light-transmitting protective plate 17.
As described above, it is possible to manufacture an illumination light source with less light emission unevenness over a wider surface using the difference between the lengths of the major axis portion and the minor axis portion of the cross-sectional shape.

(Example 7)
FIG. 12 is a view showing the illumination light source from the light emitting surface side according to the seventh embodiment. FIG. 13 is a view showing a cross-sectional shape of light emitted from the plurality of semiconductor laser devices of FIG. 12 to the light-transmitting protective plate.

As shown in FIG. 12, the illumination light source 800 includes a plurality of semiconductor laser devices 500 according to the fifth embodiment arranged in a lattice pattern, a light-transmissive protective plate 18 that covers the plurality of semiconductor laser devices 500, and the like. (It is not shown about components other than the above.).
The light-transmissive protective plate 18 is provided with a uniform fluorescent layer over the entire surface (the fluorescent layer is not shown).

The laser light emitted from the semiconductor laser device 500 to the light-transmissive protective plate 18 has an elliptical cross-sectional shape that is long in the vertical direction with respect to the active layer and short in the parallel direction.
The semiconductor laser device 500 having such a radiation characteristic is arranged in a lattice shape so that the cross-sectional shapes with respect to the light transmissive protective plate 18 are in contact with each other as shown in FIG. White visible light with little uneven emission is emitted from the provided fluorescent layer.
As described above, it is possible to manufacture an illumination light source with less unevenness of light emission over a wider surface by using the difference between the length of the major axis and the minor axis of the cross-sectional shape with a simple arrangement.

1 is a perspective view of a semiconductor laser light emitting device according to embodiments 1 and 2 of the present invention. FIG. FIG. 2 is a partial cutaway view of FIG. 1 for explaining the structure of the semiconductor laser light emitting device according to the first embodiment of the present invention. FIG. 3 is a partial cutaway view of FIG. 1 for explaining the structure of a semiconductor laser light emitting device according to Embodiment 2 of the present invention. It is the top view which looked at the light source for illumination by Example 3 of this invention from the light emission surface side. It is a side view of the light source for illumination by Example 3 of this invention. It is the figure which showed the cross-sectional shape of the light radiated | emitted from the some semiconductor laser light-emitting device of FIG. 4 to the light-transmissive protective board by Example 3 of this invention. It is the top view which looked at the light source for illumination by Example 4 of this invention from the light emission surface side. It is the top view which looked at the light source for illumination by Example 5 of this invention from the light emission surface side. It is the figure which showed the cross-sectional shape of the light radiated | emitted from the several semiconductor laser apparatus of FIG. 8 to the light transmissive protection board by Example 5 of this invention. It is the top view which looked at the light source for illumination by Example 6 of this invention from the light emission surface side. It is the figure which showed the cross-sectional shape of the light radiated | emitted from the some semiconductor laser apparatus of FIG. It is the top view which looked at the light source for illumination by Example 7 of this invention from the light emission surface side. It is the figure which showed the cross-sectional shape of the light radiated | emitted from the several semiconductor laser apparatus of FIG. 12 to the light transmissive protection board by Example 7 of this invention. It is the figure which showed the arrangement | positioning form of the lens on a semiconductor laser chip in the semiconductor laser light-emitting device by the modification of Example 1 and 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Semiconductor laser chip 2, 2a ... Kamaboko type lens 3, 14, 15, 16, 17, 18 ... Light-transmitting protective plate 4 .... Fluorescent layer 5 .... ··· Submount 6 ··· Photodiode chip 7 ··· Lead pin 8 ··· Common lead pin 9 ··· Hermetic glass 10 ··· Metal wire DESCRIPTION OF SYMBOLS 11 ... Can 12 ... Stem 13,13a ... Plano-concave lens 19 ... Substrate 100, 200 ... Semiconductor laser light emitting device 300, 400, 600, 700, 800 ... For illumination Light source 500... Semiconductor laser device

Claims (12)

  A semiconductor laser chip that emits diffused light having a predetermined wavelength and an elliptical cross section, a lens that adjusts the cross-sectional shape of the diffused light, and receives the adjusted light and converts it into light having a wavelength different from the predetermined wavelength. A kamaboko-shaped lens disposed so as to shorten the long diameter of the cross section of the diffused light, and a plano-concave lens disposed so as to increase the short diameter of the cross section of the diffused light. At least one of the light-emitting devices.   The light-emitting device according to claim 1, wherein the lens is a semi-cylindrical lens that approximates a diffused light cross section to a circle.   The light-emitting device according to claim 1, wherein the lens is a plano-concave lens that approximates a diffused light section to a circle.   The semiconductor laser chip is an edge-emitting laser chip that has a P-type electrode and an N-type electrode, emits purple to blue laser light in two opposite directions parallel to the PN junction surface. The light emitting device according to claim 1, wherein the light emitting device is provided.   The semiconductor laser chip has two end faces for emitting laser light, of which the end face reflectance on the side facing the wavelength conversion member is set to 20% or less, and the opposite end face reflectance is set to 60% or more. The light-emitting device according to claim 4.   The said wavelength conversion member is excited by the laser beam radiate | emitted from the said semiconductor laser chip | tip, and produces | generates the light of a wavelength longer than the wavelength of a laser beam. Light-emitting device.   The light emitting device according to claim 1, wherein the wavelength conversion member is excited by laser light emitted from the semiconductor laser chip to generate white visible light.   A plurality of light emitting devices, wherein the plurality of light emitting devices are arranged in a straight line or a lattice at equal intervals so that light is emitted in a fixed direction, covered with a light transmissive protective plate, The light source for illumination which adjoins so that the irradiation area | region of a diffused light may mutually contact, and each light-emitting device is a light-emitting device as described in any one of Claims 1-7.   The illumination light source according to claim 8, wherein a plurality of adjacent light emitting devices are closely arranged.   A plurality of semiconductor laser chips that emit diffused light having a predetermined wavelength and an elliptical cross section, and wavelength conversion that receives the diffused light emitted by the plurality of semiconductor laser chips, converts the light into light having a wavelength different from the predetermined wavelength, and emits the light The semiconductor laser chips are arranged in one row or in a plurality of parallel rows, the irradiation regions for the wavelength conversion member are in contact with each other, and the short diameter portions of the irradiation regions are continuously arranged in a straight line. A light source for illumination characterized by being made.   The illumination light source according to claim 10, wherein the semiconductor laser chips are arranged in a grid pattern.   The semiconductor laser chip emits violet to blue laser light, and the wavelength conversion member is excited by the violet to blue laser light to generate long wavelength light to emit white visible light. Item 12. The illumination light source according to Item 10 or 11.

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