JP2005268323A - Semiconductor light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device capable of suppressing change in hue of light with an observation angle. <P>SOLUTION: This semiconductor light emitting device 1 has an LED 5 which emits 1st light L<SB>1</SB>; and a fluorescent plate 7 which has a light incidence surface 71 receiving the 1st light L<SB>1</SB>and a light projection surface 72, converts part of the 1st light L<SB>1</SB>into 2nd light having a longer wavelength than the 1st light, and emits the 2nd light and 1st light L<SB>1</SB>from the light projection surface 72. The light incidence surface 71 and light emission surface 72 of the fluorescent plate 7 have unevenness. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor light emitting device.

In recent years, white LEDs using short-wavelength LEDs such as blue light-emitting diodes (LEDs) and ultraviolet LEDs and phosphors that emit fluorescence by light from these LEDs have been actively developed and put into practical use. FIG. 8 is a cross-sectional view showing an example of a white LED. A white LED 100 shown in FIG. 8 includes a light emitting element 101 that contains a nitride semiconductor and emits blue light, a case 102 that houses the light emitting element 101 in the recess 102a, and covers the recess 102a, and the blue light from the light emitting element 101 part of L _B and a plate-like phosphor 103 for converting the fluorescent yellow. Then, the yellow light generated in the blue light L _B and the phosphor 103 from the light emitting element 101 is synthesized white light L _W is emitted from the phosphor 103.

In addition to the structure shown in FIG. 8, for example, Patent Documents 1 and 2 disclose a configuration in which a light emitting element is covered with a resin containing a phosphor. Moreover, the structure which apply | coated the fluorescent substance on the light emitting element is disclosed by patent document 3 and 4. FIG. Further, Patent Document 5 discloses a configuration in which a phosphor film is formed on a light emitting element by using a sputtering method.
Japanese Patent Application Laid-Open No. 07-99345 Japanese Patent Laid-Open No. 10-93146 JP-A-11-31845 Japanese Patent Laid-Open No. 11-46019 Japanese Patent Laid-Open No. 11-46015

  The present inventors have found that the white LED disclosed in each of the above patent documents or the white LED shown in FIG. 8 causes the following problems. Here, FIG. 9A is a graph showing the change in light intensity according to the observation angle of the blue light and the yellow light contained in the white light from these white LEDs with reference to the emission central axis direction. . In FIG. 9A, the central axis direction of the light emitted from the white LED is set to an observation angle of 0 degree. Moreover, FIG.9 (b) is a figure which shows the difference in the hue by the observation angle of these white LED.

As shown in FIG. 9A, the intensity of the blue light emitted from the light emitting element and transmitted through the phosphor (graph B ₂ in the figure) increases at a relatively small observation angle, and the observation angle is large. It decreases rapidly as it becomes. This is because the ratio of blue light emitted from the light extraction surface of the light emitting element to the light extraction surface in a direction substantially perpendicular to the light extraction surface is high, and is emitted obliquely with respect to the light extraction surface. This is due to the low proportion of blue light emitted. On the other hand, yellow light generated in the phosphor emits light in various directions in the phosphor. As a result, the intensity of yellow light emitted from the phosphor gradually decreases as the observation angle increases. Therefore, as shown in FIG. 9B, when the observation angle is small (X in the figure), the blue light component contained in the white light is increased, and the image looks bluish white. Further, when the observation angle is large (Y in the figure), the yellow light component included in the white light increases, and the image looks yellowish white.

  As described above, the conventional white LED has a problem that the hue of white light varies depending on the observation angle. The present invention has been made in view of such problems, and an object of the present invention is to provide a semiconductor light-emitting device capable of suppressing a change in light color depending on an observation angle.

  In order to solve the above-described problem, a semiconductor light emitting device according to the present invention emits first light including a wavelength component in a first wavelength range and has a light extraction surface for extracting the first light. And a light incident surface that receives the first light, and a light exit surface, and a part of the first light includes a wavelength component in a second wavelength range that is longer than the first wavelength range. A fluorescent portion that converts the light into two light and emits the first and second light from the light emitting surface, and at least one of the light incident surface and the light emitting surface of the fluorescent portion has an uneven shape. It is characterized by.

  In the semiconductor light emitting device described above, at least one of the light incident surface and the light emitting surface of the fluorescent part has an uneven shape. Thereby, since the 1st light radiate | emitted from the semiconductor light-emitting element is refracted by this uneven | corrugated shape, 1st light will be spread | diffused and radiate | emitted from a fluorescence part. Therefore, since the first light emitted in a direction substantially perpendicular to the light extraction surface of the light emitting element diffuses when passing through the fluorescent portion, the ratio of the intensity of the first light at a relatively small observation angle is set to the conventional value. While suppressing it smaller than white LED, the ratio of the intensity | strength of the 1st light in a comparatively big observation angle can be made larger than conventional white LED. Therefore, according to this semiconductor light emitting device, the intensity distribution of the first light can be brought close to the intensity distribution of the second light, and therefore the observation angle of the light obtained by combining the first light and the second light It is possible to reduce the change in hue due to.

  In addition, the semiconductor light emitting device may be characterized in that the height of the convex portion or the depth of the concave portion in the concavo-convex shape of the fluorescent portion is 40 nm or more and 10 μm or less. Thereby, the 1st light radiate | emitted from the semiconductor light-emitting element can be diffused effectively in a fluorescence part.

  The semiconductor light emitting device may be characterized in that the area of the light incident surface of the fluorescent part is larger than the area of the light extraction surface of the semiconductor light emitting element. Accordingly, the first light emitted in the oblique direction from the light extraction surface of the semiconductor light emitting element can be preferably incident on the fluorescent part, so that the first light generated in the semiconductor light emitting element can be efficiently used.

  The semiconductor light emitting device may be characterized in that the uneven shape of the fluorescent part includes a plurality of columnar shapes. When the uneven shape on the light incident surface of the fluorescent part includes a plurality of columnar shapes, the incident efficiency of the first light emitted from the semiconductor light emitting element to the fluorescent part can be increased. Moreover, the uneven | corrugated shape in the light-projection surface of a fluorescence part can improve the taking-out efficiency of the 1st light which permeate | transmitted the fluorescence part, and the 2nd light generate | occur | produced in the fluorescence part by including several pillar shape. Therefore, according to this semiconductor light emitting device, the light emission efficiency of the semiconductor light emitting device can be increased.

  In the semiconductor light emitting device, the height of the plurality of columnar shapes is preferably 5 μm or less.

  Further, in the semiconductor light emitting device, the average inclination angle of the concavo-convex shape of the region including the projection of the light extraction surface on at least one of the light incident surface and the light output surface of the fluorescent portion is the concavo-convex of the other region of the surface. It may be characterized by being larger than the average inclination angle of the shape. In addition, the semiconductor light emitting device has a concavo-convex shape finer than the concavo-convex shape on the surface of the concavo-convex shape in the region including the projection of the light extraction surface on at least one of the light incident surface and the light output surface of the fluorescent part. Furthermore, it may be characterized by having. With at least one of these configurations, the first light emitted from the light extraction surface of the semiconductor light emitting element in the substantially vertical direction is more effectively diffused as compared with the first light emitted in the oblique direction. Therefore, the ratio of the intensity of the first light at a relatively small observation angle can be further reduced, and the ratio of the intensity of the first light at a relatively large observation angle can be further increased.

  The semiconductor light emitting device may further include a light reflecting film in which a plurality of openings are formed on the light emitting surface of the fluorescent part. The semiconductor light emitting device may further include a plurality of light reflecting films on the light emitting surface of the fluorescent part. With at least one of these configurations, a part of the first light which is about to pass through the fluorescent part is reflected by the light reflecting film provided on the light emitting surface of the fluorescent part and returned to the fluorescent part. Therefore, the ratio of the first light converted into the second light in the fluorescent part is increased, and the second light having an intensity distribution close to the intensity distribution of the first light depending on the observation angle can be suitably generated. . Accordingly, it is possible to further suppress a change in hue due to the observation angle of the light obtained by combining the first light and the second light.

  Further, the semiconductor light emitting device is characterized in that a coverage ratio of the region including the projection of the light extraction surface on the light emitting surface is larger than a coverage ratio of the light reflecting surface of the other region on the light emitting surface. Good. As a result, the first light having a high light intensity emitted from the light extraction surface of the semiconductor light emitting element in a substantially vertical direction is allowed to pass through the fluorescent portion for a long time, and is converted into the second light among the first light. Since the ratio can be increased, the change in hue due to the observation angle can be further suppressed.

  The semiconductor light emitting device may be characterized in that the average thickness of the fluorescent part facing the light extraction surface of the semiconductor light emitting element is thicker than the average thickness of the other part of the fluorescent part. As described above, the intensity of the first light emitted in the substantially vertical direction from the light extraction surface of the semiconductor light emitting element tends to be larger than the intensity of the first light emitted in the oblique direction. In this semiconductor light emitting device, the optical path in the fluorescent part of the first light emitted in the substantially vertical direction is longer than the optical path in the fluorescent part of the first light emitted in the oblique direction. Therefore, according to this semiconductor light emitting device, the first light having a high light intensity emitted from the light extraction surface of the semiconductor light emitting element in a substantially vertical direction is allowed to pass through the fluorescent portion for a long time. Since the rate of conversion into the light of 2 can be increased, the change in hue due to the observation angle can be further suppressed.

  The semiconductor light emitting device further includes a container having a mounting surface on which the semiconductor light emitting element is mounted, and an inclined surface that is formed obliquely with respect to the mounting surface and is provided so as to surround the mounting surface. The end surface of the part may be formed obliquely with respect to the light incident surface, and the inclined surface of the container may support the end surface of the fluorescent part. Thereby, the area of the surface for transferring heat from the fluorescent part to the container can be increased, and the heat radiation efficiency in the fluorescent part can be increased.

  According to the semiconductor light emitting device of the present invention, it is possible to suppress a change in light shade due to an observation angle.

  Hereinafter, embodiments of a semiconductor light emitting device according to the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

(Embodiment)
FIG. 1 is a side sectional view showing a configuration of an embodiment of a semiconductor light emitting device according to the present invention. Referring to FIG. 1, the semiconductor light emitting device 1 of this embodiment includes a case 3, an LED 5, a fluorescent plate 7, and a lead terminal 11.

Case 3 is a container for housing LED 5. The case 3 has a placement surface 3a on which the LED 5 is placed, and a slope 3b that is formed obliquely with respect to the placement surface 3a and is provided so as to surround the placement surface 3a. The case 3 includes a conductive material such as metal, for example, and serves to electrically connect a cathode electrode of the LED 5 described later and an external wiring of the semiconductor light emitting device 1. Further, at least one surface of the mounting surface 3a and the inclined surface 3b, so as to suitably reflect the light L ₁ from the LED 5, preferably has a light reflecting film is formed by, for example, silver plating.

The LED 5 is a semiconductor light emitting element in the present embodiment. The LED 5 has a light emitting layer made of a nitride semiconductor such as Al _x In _y Ga _1-xy N (1 ≧ x ≧ 0, 1 ≧ y ≧ 0), and is included in a wavelength range of 370 nm to 480 nm. The first light L ₁ including the wavelength component in the first wavelength range is emitted. The first light L ₁ is extracted from the light extraction surface 5 a of the LED 5. A large part of the total light amount of the first light L ₁ is emitted from the light extraction surface 5 a in a substantially vertical direction and enters the fluorescent plate 7. In addition, a portion of the first light L ₁ that is emitted obliquely from the light extraction surface 5 a or the side surface of the LED 5 is reflected by the inclined surface 3 b of the case 3 and then enters the fluorescent plate 7.

  The LED 5 is mounted on the mounting surface 3a so that the surface 5b opposite to the light extraction surface 5a and the mounting surface 3a of the case 3 face each other. A first electrode (not shown) is provided on the surface 5b of the LED 5, and the first electrode and the mounting surface 3a are joined together by a conductive adhesive (not shown) such as AuSn solder. In addition, a second electrode (not shown) is provided on the light extraction surface 5 a, and this second electrode is electrically connected to the lead terminal 11 via the bonding wire 15. The lead terminal 11 is made of a conductive material such as metal and is provided so as to penetrate the case 3. The lead terminal 11 and the case 3 are insulated from each other by an insulating member 13. The lead terminal 11 is electrically connected to the external wiring of the semiconductor light emitting device 1, and a voltage for driving the LED 5 is applied between the case 3 and the lead terminal 11.

The fluorescent plate 7 is a fluorescent part in this embodiment. The fluorescent plate 7 is formed of a fluorescent material such as ZnSSe to which Cu and I are added, for example, in a plate shape. The fluorescent plate 7 has a light incident surface 71 that faces the light extraction surface 5 a of the LED 5, and a light emitting surface 72 that is located on the opposite side of the LED 5 with respect to the light incident surface 71. The fluorescent plate 7 receives the first light L ₁ from the LED 5 on the light incident surface 71. The fluorescent plate 7 is excited by a part of the first light L ₁ and includes a wavelength component in the second wavelength range that is longer than the first wavelength range and is included in the wavelength range of 550 nm to 610 nm. The second light is emitted. Specifically, the second light includes a broad emission spectrum component having a peak in the second wavelength range and a tail in the wavelength range of 450 nm to 750 nm. The fluorescent plate 7 emits white light L ₃ including the generated second light and the remaining first light L ₁ that excites the fluorescent plate 7 from the light emitting surface 72.

Each of the light incident surface 71 and the light emitting surface 72 of the fluorescent plate 7 has an uneven shape. Here, the concavo-convex shape of the light incident surface 71 and the light exit surface 72 refers to the concavo-convex shape with respect to the first light L ₁ from the LED 5, and is formed so that the first light L ₁ is refracted by the concavo-convex shape. It is a thing. Further, the uneven shape of the light incident surface 71 and the light emitting surface 72 means that a flat surface or curved surface having a convex portion or a concave portion having a height (depth) of, for example, about 40 nm to 10 μm, or both, is disordered or regularly. It means the arranged shape. Here, the height (depth) of the concavo-convex shape is preferably in the range of 40 nm or more and 10 μm or less, as described above, and this effectively refracts visible light having a wavelength of about 400 nm to 800 nm. it can. In addition, when a fine uneven | corrugated shape is further formed in the uneven | corrugated shaped surface, it is preferable that the height (depth) of a fine uneven | corrugated shape exists in the said range.

  Further, the area of the light incident surface 71 of the fluorescent plate 7 is preferably set larger than the area of the light extraction surface 5a of the LED 5. In other words, the light incident surface 71 is preferably provided in such a size that the projection surface when the light extraction surface 5a of the LED 5 is projected onto the light incident surface 71 of the fluorescent plate 7 is included in the light extraction surface 5a. Here, the area of the light incident surface 71 refers to the size of the region determined by the outer dimensions of the light incident surface 71.

  Further, the end surface 81 of the fluorescent plate 7 is formed obliquely with respect to the light incident surface 71. Strictly speaking, the end surface 81 of the fluorescent plate 7 is formed so as to cross obliquely with respect to the surface when the uneven shape of the light incident surface 71 is smoothed or the surface when the uneven shape of the light incident surface 71 is smoothed. Has been. The fluorescent plate 7 is fitted into the case 3 so that the end surface 81 and the inclined surface 3b of the case 3 face each other, the end surface 81 is supported by the inclined surface 3b, and the end surface 81 and the inclined surface 3b are bonded by the adhesive 17. They are fixed to each other.

Although not shown, a region surrounded by the light incident surface 71 of the fluorescent plate 7, the mounting surface 3a and the inclined surface 3b of the case 3, and the surface of the LED 5 is filled with a resin that transmits the _first light L1. It is preferable. As a result, the refractive index difference inside and outside the light extraction surface 5a of the LED 5 and the refractive index difference inside and outside the light incident surface 71 of the fluorescent plate 7 are alleviated, and the incidence efficiency of the first light L ₁ from the LED 5 to the fluorescent plate 7 is increased. Can do. Moreover, it is preferable that the light emission surface 72 of the fluorescent plate 7 is covered with a resin that transmits the white light L ₃ . Thereby, the difference in refractive index between the inside and outside of the light emitting surface 72 of the fluorescent plate 7 can be relaxed, and the emission efficiency of the white light L ₃ can be increased. Further, if the resin covering the light emitting surface 72 is molded into a lens shape, it can have a function as a condensing lens for condensing the white light L ₃ . In addition, as said resin, an epoxy resin, a silicone resin, etc. are illustrated.

The semiconductor light emitting device 1 having the above configuration operates as follows. That is, when a driving voltage is applied between the lead terminal 11 and the case 3 via the wiring provided outside the semiconductor light emitting device 1, the first light L ₁ is emitted from the light extraction surface 5 a of the LED 5. The Most of the first light L ₁ is emitted from the light extraction surface 5 a in a substantially vertical direction and enters the light incident surface 71 of the fluorescent plate 7. Further, the other part of the first light L ₁ is emitted obliquely from the light extraction surface 5 a, is reflected by the inclined surface 3 b of the case 3, and then enters the light incident surface 71 of the fluorescent plate 7. When the first light L ₁ is incident on the light incident surface 71 of the fluorescent plate 7, the first light L ₁ varies in various directions (mainly with respect to the normal direction of the light extraction surface 5 a of the LED 5) depending on the uneven shape formed on the light incident surface 71. Incident while being refracted in the direction in which the angle widens.

When the first light L ₁ is incident on the light incident surface 71 of the fluorescent plate 7, a part of the first light L ₁ excites the fluorescent material in the fluorescent plate 7. Then, second light is generated in the fluorescent screen 7. On the other hand, the first light L _{1 that} has passed through the fluorescent plate 7 without exciting the fluorescent material is emitted from the light exit surface 72 of the fluorescent plate 7. When the first light L ₁ is emitted from the light emitting surface 72 of the fluorescent plate 7, the first light L ₁ is varied in various directions (mainly with respect to the normal direction of the light extraction surface 5 a of the LED 5) depending on the uneven shape formed on the light emitting surface 72. The light is emitted while being refracted in the direction in which the angle widens. Then, the second light and the first light L ₁ emitted from the light emitting surface 72 of the fluorescent screen 7 is synthesized, a white light L _3. The white light L ₃ is extracted outside the semiconductor light emitting device 1.

The semiconductor light emitting device 1 according to the present embodiment described above has the following effects. That is, in the semiconductor light emitting device 1 of the present embodiment, the light incident surface 71 and the light emitting surface 72 of the fluorescent plate 7 have an uneven shape. As a result, the first light L ₁ emitted from the LED 5 is refracted by the uneven shape, so that the first light L ₁ is diffused and emitted from the fluorescent plate 7.

Here, FIG. 2 shows the emission center of the first light L ₁ (graph B ₁ in the figure) and the second light (graph Y ₁ in the figure) included in the white light L ₃ emitted from the fluorescent plate 7. It is a graph which shows distribution of the light intensity according to the observation angle on the basis of an axial direction. As shown in this graph, in the semiconductor light emitting device 1 of the present embodiment, the first light L ₁ emitted from the light extraction surface 5 a of the LED 5 in the substantially vertical direction is diffused in the fluorescent plate 7, whereby the first light L ₁ is diffused. The light quantity ratio at a small observation angle out of the total light quantity of the light L ₁ can be reduced as compared with the conventional white LED (see FIG. 9), and the light quantity ratio at a large observation angle can be made larger than that of the conventional white LED. As a result, the intensity distributions according to the observation angles of the first light L ₁ and the second light can be made closer to each other.

Therefore, according to the semiconductor light emitting device 1 of the present embodiment, it is possible to suppress a change in the hue due to the observation angle of the white light L ₃ formed by combining the first light L ₁ and the second light.

In the semiconductor light emitting device 1 of the present embodiment, both the light incident surface 71 and the light emitting surface 72 have an uneven shape, but only one of the light incident surface 71 and the light emitting surface 72 has an uneven shape. Even if it is the structure which has, the said effect can be acquired suitably. In particular, since the light incident surface 71 has a concavo-convex shape, the first light L ₁ is hardly totally reflected on the light incident surface 71, and the first light L ₁ can be efficiently taken into the fluorescent plate 7. Further, if the light emitting surface 72 has an uneven shape, the first light L ₁ and the second light can be efficiently emitted from the light emitting surface 72.

Further, as in this embodiment, the area of the light incident surface 71 of the fluorescent plate 7 is preferably larger than the area of the light extraction surface 5a of the LED 5. Since this makes it possible to suitably enters the first light L ₁ emitted in an oblique direction of the first light L ₁ emitted from LED5 of the light extraction surface 5a to the fluorescent screen 7, it occurred at LED5 The first light L ₁ can be used efficiently.

Further, as in the present embodiment, it is preferable that the end surface 81 of the fluorescent plate 7 is formed obliquely with respect to the light incident surface 71 and the end surface 81 is supported by the inclined surface 3 b of the case 3. In the fluorescent plate 7, when a part of the _first light L1 is converted into the second light, heat is generated due to energy loss caused by the Stokes shift. The end surface 81 of the fluorescent plate 7 is supported by the inclined surface 3 b of the case 3, so that heat generated in the fluorescent plate 7 can be suitably transmitted from the fluorescent plate 7 to the case 3. Further, the end surface 81 of the fluorescent plate 7 is formed obliquely, and the end surface 81 is supported by the inclined surface 3b, so that a large area of the surface for transmitting heat from the fluorescent plate 7 to the case 3 can be secured. Heat dissipation efficiency can be increased. Further, for example, as compared with the case where the light incident surface of the fluorescent plate and the upper surface of the case are bonded, there is no need for a bonding allowance for bonding to the fluorescent plate, so that the external dimensions of the fluorescent plate 7 can be reduced. Moreover, it is preferable that the end surface 81 of the fluorescent plate 7 is covered with a light shielding member (for example, the case 3 of the present embodiment). Thus, it is possible to prevent the light from leaking from the end face 81 of the fluorescent screen 7, further reducing the change in the hue of the white light L ₃ by viewing angle.

In the semiconductor light emitting device 1, it is preferable that the light extraction surface 5a of the LED 5 also has an uneven shape. Thus, it is possible to increase the first light extraction efficiency of the light L ₁ from the LED 5, since the first light L ₁ is incident on the fluorescent plate 7 diffuses the observation angle of the first light L ₁ The intensity change can be further suppressed. Further, a resin that fills a region surrounded by the light incident surface 71 of the fluorescent plate 7, the mounting surface 3a and the inclined surface 3b of the case 3, and the surface of the LED 5, and a resin that covers the light emitting surface 72 of the fluorescent plate 7 are, for example, glass beads. and SiO _2, preferably contains TiO ₂ such as an optical diffusing material. As a result, the white light L ₃ is further diffused, so that a change in hue due to the observation angle can be further suppressed.

Further, in the semiconductor light emitting device having the light emitting layer made of a nitride semiconductor like the LED 5 of the present embodiment, the first light L ₁ is not only blue light but also light of the peripheral wavelength (for example, ultraviolet light, near ultraviolet light). May be included. Such light such as ultraviolet light and near ultraviolet light tends to deteriorate the resin. On the other hand, in the semiconductor light emitting device 1 of the present embodiment, when the first light L ₁ from the LED 5 passes through the fluorescent plate 7, ultraviolet light or near ultraviolet light contained in the first light L ₁ is applied to the fluorescent plate 7. Since it is absorbed, deterioration of the resin provided so as to cover the fluorescent screen 7 can be suppressed.

(First modification)
Next, a modification of the semiconductor light emitting device 1 of the above embodiment will be described. FIG. 3A is a side sectional view showing the configuration of the semiconductor light emitting device 1a according to the first modification. FIG. 3B is an enlarged view of the light incident surface 73 of the fluorescent screen 7a. The difference between the semiconductor light emitting device 1a of the present modification and the semiconductor light emitting device 1 of the above embodiment is the surface shape of the light incident surface 73 of the fluorescent plate 7a. Since the other configuration of the semiconductor light emitting device 1a is the same as that of the above embodiment, a detailed description thereof is omitted.

Referring to FIGS. 3A and 3B, the uneven shape on the light incident surface 73 of the fluorescent plate 7a of the present modification is such that a plurality of minute cylinders 19 are arranged in the plane direction of the light incident surface 73. It also exhibits a so-called photonic crystal structure. The pitch p between the cylinders 19 is, for example, 2 μm, the diameter d of the cylinders 19 is, for example, 1 μm, and the height h of the cylinders 19 is, for example, 1 μm. In order to be incident efficiently first light L ₁ from LED5 the fluorescent plate 7a, the height h of the cylinder 19 is preferably 40nm or more 5μm or less.

The semiconductor light emitting device 1a according to this modification has the following effects. That is, according to the semiconductor light emitting device 1a, by irregularities in the light incident surface 73 of the fluorescent screen 7a exhibits a photonic crystal structure comprising a plurality of cylindrical 19, the first light L ₁ is fluorescent plate 7a emitted from LED5 In addition, the incident efficiency of the first light L _{1 on} the fluorescent plate 7 a can be increased.

In this modification, the uneven shape of the light incident surface 73 includes a plurality of cylinders 19, but the uneven shape of the light exit surface 72 may include a plurality of cylinders 19. As a result, it is possible to increase the extraction efficiency of the first light L ₁ transmitted through the fluorescent plate 7a and the second light generated in the fluorescent plate 7a from the light emitting surface 72, so that the light emission efficiency of the semiconductor light emitting device 1a is increased. Can do. Further, the uneven shape of the light incident surface 73 (light emitting surface 72) may include a column shape other than a cylinder such as a square column or a hexagonal column instead of the column 19.

(Second modification)
FIG. 4A is a side sectional view showing the configuration of the semiconductor light emitting device 1b according to the second modification. The difference between the semiconductor light emitting device 1b of the present modification and the semiconductor light emitting device 1 of the above embodiment is the shape of the light emission surface 74 of the fluorescent plate 7b. The other configuration of the semiconductor light emitting device 1b is the same as that in the above embodiment.

  Referring to FIG. 4A, in the light emitting surface 74 of the fluorescent plate 7b of this modification, the average inclination angle of the uneven shape of the region 74a including the projection of the light extraction surface 5a of the LED 5 is the uneven shape of the other region. The concavo-convex shape is formed so as to be larger than the average inclination angle. In other words, the concavo-convex shape in the region 74a is formed with a steeper side surface than the concavo-convex shape in other regions. As an uneven shape having a large average inclination angle, for example, the shape in which the interval between the apexes of adjacent convex portions (or the interval between the bottoms of adjacent concave portions) is formed narrower than other regions, or adjacent convex portions The shape etc. in which the height (or the depth of an adjacent recessed part) is formed higher (deeper) than another area | region are illustrated.

  Here, the region 74a including the projection of the light extraction surface 5a of the LED 5 includes a region corresponding to the projection surface when the light extraction surface 5a is projected onto the light emission surface 74 by the normal line of the light extraction surface 5a. It shall refer to an area.

The semiconductor light emitting device 1b according to this modification has the following effects. That is, in the semiconductor light-emitting device 1b, of the first light L ₁ emitted from LED5 of the light extraction surface 5a, the first light L ₁ is diffused by the large unevenness of the tilt angle to be emitted in a substantially vertical direction Since the first light L ₁ emitted in the oblique direction is diffused by the unevenness having a small inclination angle, the first light L ₁ emitted in the vertical direction is more than the first light L ₁ emitted in the oblique direction. Diffuses over a wide angle. Therefore, according to the semiconductor light-emitting device 1b, while suppressing a first intensity ratio of the light L ₁ in a small viewing angle effectively, it is possible to increase the first intensity ratio of the light L ₁ in a large viewing angle The intensity distributions according to the observation angles of the first light L ₁ and the second light can be made closer to each other, and the change in hue due to the observation angle of the white light L ₃ can be more effectively suppressed.

In this modification, the average inclination angle of the unevenness on the light exit surface 74 varies depending on the region, but the average inclination angle of the unevenness on the light incident surface may vary depending on the region. Specifically, the uneven shape of the light incident surface is such that the average inclination angle of the unevenness in the region including the projection of the light extraction surface 5a of the LED 5 on the light incident surface is larger than the average inclination angle of the unevenness in the other regions. May be formed. Accordingly, the first of the light L ₁ incident on the fluorescent plate, while the first light L ₁ emitted substantially vertically from the light extraction surface 5a is diffused more wide angle by a relatively large irregularities of the tilt angle Since the light enters the fluorescent plate, the same effect as that obtained when the average inclination angle of the unevenness on the light exit surface 74 varies depending on the region can be obtained.

Further, in this modification, the first light L ₁ is diffused at a wider angle by varying the average inclination angle of the unevenness on the light exit surface 74 (or light incident surface) depending on the region. As shown in b), the surface of the unevenness 75a in the region including the projection of the light extraction surface 5a on the light exit surface 75 (or the light incident surface) further has unevenness 75b finer than the unevenness 75a. The first light L ₁ can be diffused at a wider angle. By having such a concavo-convex shape on at least one of the light incident surface and the light emitting surface of the fluorescent plate, the same effect as in this modification can be obtained.

(Third Modification)
FIG. 5A is a side sectional view showing a configuration of a semiconductor light emitting device 1c according to a third modification. The semiconductor light emitting device 1c of this modification is different from the semiconductor light emitting device 1 of the above embodiment in that the light reflecting film 21 is provided on the light emitting surface 72 of the fluorescent plate 7. The other configuration of the semiconductor light emitting device 1c is the same as that in the above embodiment.

  In this modification, the light reflecting film 21 on the light emitting surface 72 is formed so as to cover a part of the light emitting surface 72. Here, FIG. 5B is an enlarged plan view showing the light reflecting film 22 as an example of the shape of the light reflecting film 21 provided on the light emitting surface 72 of the fluorescent plate 7. Referring to FIG. 5B, the light reflecting film 22 has a plurality of openings 22a, and the light emission surface 72 of the fluorescent plate 7 is exposed in the openings 22a. FIG. 5C is an enlarged plan view showing a light reflecting film 23 as another example of the shape of the light reflecting film 21. Referring to FIG. 5C, a plurality of light reflecting films 23 are provided on the light emitting surface 72 of the fluorescent plate 7 so as to be separated from each other.

  Further, the coverage of the light reflecting films 21 to 23 with respect to the light emitting surface 72 is preferably relatively large in the region including the projection of the light extraction surface 5a on the light emitting surface 72 and relatively small in the other regions.

  The light reflecting films 21 to 23 are preferably formed by forming a metal such as Ag on the light emitting surface 72 by vapor deposition or the like through a resist pattern and removing the resist pattern.

The semiconductor light emitting device 1c according to this modification has the following effects. That is, in the semiconductor light emitting device 1 c, a part of the first light L ₁ that is about to pass through the fluorescent plate 7 is the light reflecting film 21 (or the light reflecting films 22 and 23) provided on the light emitting surface 72 of the fluorescent plate 7. And is returned into the fluorescent screen 7. Therefore, the ratio of the first light L ₁ converted into the second light in the fluorescent plate 7 is increased, and the second light having an intensity distribution close to the intensity distribution of the first light L ₁ according to the observation angle is preferably used. Can be generated. Accordingly, it is possible to further suppress the change in the hue due to the observation angle of the white light L ₃ obtained by combining the first light L ₁ and the second light.

Further, as in the present modification, the coverage by the light reflecting film 21 (or the light reflecting films 22, 23) in the region including the projection of the light extraction surface 5 a of the light emitting surface 72 is the other region of the light emitting surface 72. It is preferable that the coverage is greater than Thus, longer passed through the fluorescent plate in 7 large first light L ₁ of the light intensity emitted substantially perpendicularly from LED5 of the light extraction surface 5a, the first second light of the light L ₁ Therefore, the change in hue due to the observation angle can be further suppressed.

  Further, as shown in FIG. 5B, in the configuration in which the light reflecting film 22 has a plurality of openings 22a, the light reflecting film 22 is integrally connected, so that heat generated in the fluorescent plate 7 is reflected by light. It can be efficiently released through the membrane 22. At this time, the light reflecting film 22 is preferably made of a material having high thermal conductivity such as metal.

(Fourth modification)
FIG. 6 is a side sectional view showing a configuration of a semiconductor light emitting device 1d according to a fourth modification. The semiconductor light emitting device 1d of the present modification is different from the semiconductor light emitting device 1 of the above embodiment in that the thickness of the fluorescent plate 7d differs depending on the part. Other configurations of the semiconductor light emitting device 1d are the same as those in the above embodiment.

  Referring to FIG. 6, the fluorescent plate 7d of the present modification has the following characteristics. That is, the average thickness of the portion 76 of the fluorescent plate 7d facing the light extraction surface 5a of the LED 5 is formed to be thicker than the average thickness of other portions of the fluorescent plate 7d. Here, the average thickness of the fluorescent plate 7d refers to the average value of the distance between the uneven surface of the light incident surface 71 and the uneven surface of the light exit surface 72 in the thickness direction of the fluorescent plate 7d. To do.

The effect of the semiconductor light emitting device 1d according to this modification will be described. As described above, a large part of the total amount of the first light L ₁ generated in the LED 5 is emitted from the light extraction surface 5 a in a substantially vertical direction and enters the fluorescent plate 7. In the semiconductor light emitting device 1d according to the present modification, the average thickness of the portion 76 of the fluorescent plate 7d facing the light extraction surface 5a is larger than the average thickness of the other portions, so that the light is emitted from the light extraction surface 5a in the vertical direction. optical path in the first in fluorescent plate 7d of the optical L ₁ is longer than the optical path of the first in fluorescent plate 7d of the light L ₁ emitted in an oblique direction. Therefore, according to the semiconductor light emitting device 1d of the present modification, the first light L ₁ having a large light intensity emitted from the light extraction surface 5a of the LED 5 in the substantially vertical direction is allowed to pass through the fluorescent plate 7 for a long time. Since the conversion efficiency of the _first light L ₁ into the second light can be increased, a change in hue due to the observation angle can be further suppressed.

In this modification, the fluorescent plate 7 can also be formed in a convex lens shape. As a result, the fluorescent plate 7 can have both a lens function for condensing the white light L ₃ and a fluorescent function, so that the number of parts can be reduced.

  In the embodiment and each modification described above, a configuration including a plurality of LEDs 5 may be used. That is, by mounting a plurality of LEDs 5 on the mounting surface 3a of the case 3, a semiconductor light emitting device with higher brightness can be realized. FIG. 7A and FIG. 7B are cross-sectional views showing configurations when the semiconductor light emitting devices according to the second and fourth modifications described above each include a plurality of LEDs 5. As illustrated in FIG. 7A, when the semiconductor light emitting device according to the second modification includes a plurality of LEDs 5, a plurality of regions of the light emission surface 78 including projections of the light extraction surfaces 5 a of the plurality of LEDs 5. The fluorescent plate 7e may be formed so that the average inclination angle of the uneven shape in each of the 78a is larger than the average inclination angle of the uneven shape in the region other than the region 78.

  As shown in FIG. 7B, when the semiconductor light emitting device according to the fourth modification includes a plurality of LEDs 5, a plurality of portions 77 of the fluorescent plate 7f facing the light extraction surface 5a of each of the plurality of LEDs 5. The fluorescent plate 7f may be formed so that the average thickness in each portion is larger than the average thickness in other portions. When the semiconductor light emitting device according to the third modification includes a plurality of LEDs 5, the coverage by the light reflecting film in each of the plurality of regions of the light emitting surface including the projection of the light extraction surface 5a of each of the plurality of LEDs 5 However, it is preferable to form the light reflecting film so as to be larger than the coverage in other regions.

  Next, examples corresponding to the embodiment and each modification will be described.

(First embodiment)
In this example, the semiconductor light emitting device 1 according to the above embodiment was created. First, as LED 5, a blue LED in which a light emitting layer was provided on an n-type conductive GaN substrate was prepared. That is, the surface of the n-type conductive GaN substrate is cleaned, TMG (trimethyl gallium) gas, TMI (trimethyl indium) gas, nitrogen gas and dopant gas are flowed on the substrate surface together with the carrier gas, and the GaN compound semiconductor is formed by MOCVD. A light emitting layer (including an n-type cladding layer, an active layer, and a p-type cladding layer) was formed on the substrate surface. Then, an anode electrode was formed on the p-type cladding layer, and a cathode electrode was formed on the back surface of the n-type conductive GaN substrate, respectively, by EB (Electron Beam) evaporation. Thereafter, scribing and braking were performed on the substrate on which the light emitting layer was formed, and the substrate was divided into 2 mm squares.

  Subsequently, Case 3 was formed. A mounting surface 3a and a slope 3b having a diameter of 4 mm were formed on the material of the case 3, and the mounting surface 3a and the slope 3b were subjected to Ag plating having a high reflection coefficient in the visible light region. Then, a through hole was formed in the case 3 and the lead terminal 11 was inserted, and then fixed by the insulating member 13.

  Subsequently, the formed LED 5 was placed at substantially the center on the placement surface 3a so that the anode electrode and the placement surface 3a face each other. At this time, the anode electrode and the mounting surface 3a were joined by AuSn solder.

Subsequently, the cathode electrode of the LED 5 and the lead terminal 11 of the case 3 were connected by a bonding wire 15. At this time, a gold wire having a diameter of 75 μm was used as the bonding wire 15 so that a relatively large current can be passed through the LED 5 to increase the intensity of the first light L ₁ .

  Subsequently, the fluorescent plate 7 was formed. That is, a bulk ZnSSe crystal in which I was diffused by a halogen transport method was formed, and this bulk ZnSSe crystal was heated in a Zn, Cu atmosphere to diffuse Cu into the ZnSSe. Subsequently, the lump ZnSSe crystal was polished to a thickness of 0.5 mm using a rough polishing disk to form the light incident surface 71 and the light emitting surface 72, and then cut into a shape that fits in the case 3. The surface roughness of the light incident surface 71 and the light emitting surface 72 of the fluorescent plate 7 formed in this way was the maximum height Rmax = 1 μm.

  Subsequently, after injecting a transparent resin into a recess formed by the mounting surface 3 a and the inclined surface 3 b of the case 3, a resin adhesive added with a conductive filler is applied to the end surface 81 of the fluorescent plate 7, and the end surface 81 and the case 3 are applied. The slope 3b was bonded and fixed. Then, an epoxy resin was molded into a lens shape on the fluorescent plate 7 by a casting method. Thus, the semiconductor light emitting device 1 was completed.

When a driving voltage is applied to the semiconductor light emitting device 1, the first light L ₁ generated in the LED 5 and the second light generated in the fluorescent screen 7 complement each other, and the white light L ₃ can be observed. It was. Furthermore, when the observation angle was changed, the white light L ₃ exhibited substantially uniform chromaticity (white) regardless of the observation angle.

(Second embodiment)
In this example, the semiconductor light emitting device 1a according to the first modified example was produced. First, in the same manner as in Example 1, the LED 5 and the case 3 were prepared, and the LED 5 was mounted on the case 3.

  Subsequently, a fluorescent plate 7a was formed. That is, a bulk ZnSSe crystal in which I was diffused by a halogen transport method was formed, and Cu was diffused inside ZnSSe. Subsequently, the lump ZnSSe crystal was mirror-polished to a thickness of 0.5 mm using a polishing disk to form a light incident surface and a light output surface. Then, a resist was applied to the light incident surface and the light emitting surface, and exposure and RIE (reactive ion etching) were performed to form a photonic crystal structure having a plurality of cylindrical shapes. At this time, the diameter of the cylinder was 1 μm, the height was 1 μm, and the pitch between the cylinders was 2 μm. The ZnSSe crystal was cut into a shape that fits in case 3.

  Subsequently, after injecting a transparent resin into the recess formed by the mounting surface 3a and the inclined surface 3b of the case 3, the end surface of the fluorescent plate 7a and the inclined surface 3b of the case 3 are bonded and fixed, and an epoxy resin is placed on the fluorescent plate 7 as a lens. Molded into a shape. Thus, the semiconductor light emitting device 1a was completed.

When a driving voltage is applied to the semiconductor light emitting device 1a, the first light L ₁ generated in the LED 5 and the second light generated in the fluorescent plate 7b complement each other, and the white light L ₃ can be observed. It was. Furthermore, when the observation angle was changed, the white light L ₃ exhibited substantially uniform chromaticity (white) regardless of the observation angle.

(Third embodiment)
In this example, the semiconductor light emitting device 1b according to the second modified example was created. First, in the same manner as in Example 1, the LED 5 and the case 3 were prepared, and the LED 5 was mounted on the case 3.

Subsequently, a fluorescent plate 7b was formed. That is, a bulk phosphor was prepared by press molding and sintering Ce-activated YAG powder (YAlO ₃ : Ce). Then, after the light emitting surface 71 and the light emitting surface 74 are formed by polishing the massive phosphor to a thickness of 0.7 mm using a rough polishing disk, the surface roughness near the center of the light emitting surface 74 is compared. The outer periphery of the light exit surface 74 was further polished so that the surface roughness near the outer periphery was relatively fine and cut into a shape that fits in the case 3. The surface roughness of the light exit surface 74 of the fluorescent plate 7b formed in this way was a maximum height Rmax = about 2 μm near the center and a maximum height Rmax = about 0.5 μm near the outer periphery.

  Subsequently, after injecting a transparent resin into the recess formed by the mounting surface 3a and the inclined surface 3b of the case 3, a resin adhesive is applied to the end surface of the fluorescent screen 7b, and the end surface 81 and the inclined surface 3b of the case 3 are bonded and fixed. did. At this time, the fluorescent plate 7 was fixed to the case 3 so that the light extraction surface 5a of the LED 5 and the center of the light incident surface 71 of the fluorescent plate 7b face each other. Then, an epoxy resin was molded into a lens shape on the fluorescent plate 7b by a casting method. Thus, the semiconductor light emitting device 1b was completed.

When a driving voltage is applied to the semiconductor light emitting device 1b, the first light L ₁ generated in the LED 5 and the second light generated in the fluorescent plate 7b complement each other, and the white light L ₃ can be observed. It was. Furthermore, when the observation angle was changed, the white light L ₃ exhibited substantially uniform chromaticity (white) regardless of the observation angle, and the light intensity was substantially constant regardless of the observation angle. .

(Fourth embodiment)
In this example, a semiconductor light emitting device 1c according to the third modification was produced. First, in the same manner as in Example 1, the LED 5 and the case 3 were prepared, and the LED 5 was mounted on the case 3. In addition, the diameter of the gold wire which connects the cathode electrode of LED5 and the lead terminal 11 was 50 micrometers.

  Subsequently, the fluorescent plate 7 was formed. That is, a bulk ZnSSe crystal in which I was diffused by a halogen transport method was formed, and this bulk ZnSSe crystal was heated in a Zn, Cu atmosphere to diffuse Cu into the ZnSSe. Subsequently, the lump ZnSSe crystal was polished to a thickness of 0.4 mm by using a coarse polishing disk to form the light incident surface 71 and the light emitting surface 72, and then cut into a shape that fits in the case 3. The surface roughness of the light incident surface 71 and the light emitting surface 72 of the fluorescent plate 7 formed in this way was the maximum height Rmax = 1.5 μm.

  Subsequently, the light reflecting film 21 was formed by vapor-depositing Ag on the light emitting surface 72 of the fluorescent plate 7. At this time, the light reflecting film 21 was formed so that the coverage by the light reflecting film 21 near the center of the light emitting surface 72 was relatively large and the coverage by the light reflecting film 21 near the outer periphery was relatively small. Then, after injecting a transparent resin into the recess formed by the mounting surface 3a and the inclined surface 3b of the case 3, the end surface of the fluorescent plate 7 and the inclined surface 3b of the case 3 are bonded and fixed, and an epoxy resin is formed on the fluorescent plate 7 in a lens shape. Molded into. At this time, the fluorescent plate 7 was fixed to the case 3 so that the light extraction surface 5a of the LED 5 and the center of the light incident surface 71 of the fluorescent plate 7 face each other. Thus, the semiconductor light emitting device 1c was completed.

When a driving voltage is applied to the semiconductor light emitting device 1c, the first light L ₁ generated in the LED 5 and the second light generated in the fluorescent plate 7b complement each other, and the white light L ₃ can be observed. It was. Furthermore, when the observation angle was changed, the white light L ₃ exhibited substantially uniform chromaticity (white) regardless of the observation angle, and the light intensity was substantially constant regardless of the observation angle. .

(Fifth embodiment)
In this example, the semiconductor light emitting device 1d according to the fourth modification was produced. First, in the same manner as in Example 1, the LED 5 and the case 3 were prepared, and the LED 5 was mounted on the case 3. In this example, when the substrate on which the light emitting layer was formed was divided, the substrate was divided into 3 mm squares. Moreover, the diameter of the mounting surface 3a of the case 3 was 5 mm. Moreover, the diameter of the gold wire which connects the cathode electrode of LED5 and the lead terminal 11 was 30 micrometers.

  Subsequently, a fluorescent plate 7d was formed. That is, a powdery raw material in which Cu and I were mixed with ZnSSe was sintered by an imprint technique. At this time, the surface to be the light incident surface 71 and the light emitting surface 72 was molded so as to have a rough uneven shape. Further, the fluorescent plate 7d was formed so that the average thickness near the center of the fluorescent plate 7d was larger than the average thickness near the outer periphery. Specifically, the average thickness at the center of the fluorescent plate 7d was 0.5 mm, and the average thickness at the outer periphery was 0.3 mm.

  Subsequently, after injecting transparent resin into the recess formed by the mounting surface 3a and the inclined surface 3b of the case 3, the end surface of the fluorescent plate 7d and the inclined surface 3b of the case 3 are bonded and fixed, and an epoxy resin is formed on the fluorescent plate 7 with a lens. Molded into a shape. At this time, the fluorescent plate 7d was fixed to the case 3 so that the light extraction surface 5a of the LED 5 and the center of the light incident surface 71 of the fluorescent plate 7d face each other. Thus, the semiconductor light emitting device 1d was completed.

When a driving voltage is applied to the semiconductor light emitting device 1d, the first light L ₁ generated in the LED 5 and the second light generated in the fluorescent plate 7b complement each other, and the white light L ₃ can be observed. It was. Furthermore, when the observation angle was changed, the white light L ₃ exhibited substantially uniform chromaticity (white) regardless of the observation angle, and the light intensity was substantially constant regardless of the observation angle. .

(Comparative example)
Here, in order to verify the effects of the above embodiments, a white LED having the configuration shown in FIG. 8 was created. First, in the same manner as in Example 1, the LED 5 and the case 3 were prepared, and the LED 5 was mounted on the case 3.

  Subsequently, a bulk ZnSSe crystal in which I was diffused by a halogen transport method was formed, and Cu was diffused inside the ZnSSe. Subsequently, the bulk ZnSSe crystal was mirror-polished using a polishing disc to form a light incident surface and a light output surface, and then cut into a shape that fits in the case 3. Thereafter, the fluorescent plate was fixed to the case 3 in the same manner as in the first example to complete a white LED.

  When a driving voltage was applied to the white LED, white light could be observed. However, when the observation angle was changed, white light that was slightly bluish was observed at a small observation angle, and yellowish white light was observed at a large observation angle.

  The semiconductor light emitting device according to the present invention is not limited to the above-described embodiments, modifications, and examples, and various other modifications are possible. For example, in the above embodiment, the fluorescent plate is configured as a single layer and receives the first light and generates the second light. However, the fluorescent plate may be configured by a plurality of layers that emit fluorescence having different wavelengths. Good. At this time, the fluorescent plate layer may be plate-shaped or film-shaped. As described above, when the fluorescent plate emits fluorescent light having a plurality of wavelengths different from each other, the semiconductor light emitting device can emit light having excellent color rendering properties.

FIG. 1 is a side sectional view showing a configuration of an embodiment of a semiconductor light emitting device according to the present invention. FIG. 2 is a graph showing the change in light intensity according to the observation angle of the first light and the second light included in the white light emitted from the fluorescent plate with reference to the emission central axis direction. FIG. 3A is a side sectional view showing the configuration of the semiconductor light emitting device according to the first modification. FIG. 3B is an enlarged view of the light incident surface of the fluorescent plate. FIG. 4A is a side sectional view showing the configuration of the semiconductor light emitting device according to the second modification. FIG. 4B is a diagram illustrating an example of the uneven shape on the light emitting surface (or the light incident surface). FIG. 5A is a side sectional view showing a configuration of a semiconductor light emitting device according to a third modification. FIG. 5B and FIG. 5C are enlarged plan views showing an example of the shape of the light reflecting film provided on the light emitting surface of the fluorescent plate. FIG. 6 is a side sectional view showing a configuration of a semiconductor light emitting device according to a fourth modification. FIG. 7A and FIG. 7B are cross-sectional views showing the configuration in the case where the semiconductor light emitting device according to the second and fourth modified examples includes a plurality of LEDs, respectively. FIG. 8 is a cross-sectional view showing an example of a white LED. FIG. 9A is a graph showing a change in light intensity according to an observation angle of blue light and yellow light included in white light from the white LED shown in FIG. . FIG. 9B is a diagram showing a difference in hue depending on the observation angle of the white LED shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1a-1d ... Conductor light-emitting device, 3 ... Case, 3a ... Mounting surface, 3b ... Slope, 5a ... Light extraction surface, 7, 7a-7f ... Fluorescent screen, 11 ... Lead terminal, 13 ... Insulating member, 15 DESCRIPTION OF SYMBOLS ... Bonding wire, 17 ... Adhesive, 19 ... Cylinder, 21-23 ... Light reflection film, 71, 73 ... Light incident surface, 72, 74, 75, 78 ... Light emission surface, 81 ... End surface.

Claims (12)

A semiconductor light-emitting element having a light extraction surface that emits first light including a wavelength component in the first wavelength range and extracts the first light;
A light incident surface for receiving the first light; and a light exit surface, wherein a part of the first light includes a wavelength component in a second wavelength range that is longer than the first wavelength range. A fluorescent part that converts the light into second light and emits the first and second light from the light exit surface;
The semiconductor light emitting device according to claim 1, wherein at least one of the light incident surface and the light emitting surface of the fluorescent portion has an uneven shape.   2. The semiconductor light emitting device according to claim 1, wherein a height of the convex portion or a depth of the concave portion in the concavo-convex shape of the fluorescent portion is 40 nm or more and 10 μm or less.   3. The semiconductor light emitting device according to claim 1, wherein an area of the light incident surface of the fluorescent portion is larger than an area of the light extraction surface of the semiconductor light emitting element.   The semiconductor light-emitting device according to claim 1, wherein the uneven shape of the fluorescent part includes a plurality of columnar shapes.   The semiconductor light emitting device according to claim 4, wherein a height of the plurality of columnar shapes is 5 μm or less.   The average inclination angle of the concavo-convex shape of the region including the projection of the light extraction surface on at least one of the light incident surface and the light output surface of the fluorescent portion is the concavo-convex shape of the other region of the surface. The semiconductor light-emitting device according to claim 1, wherein the semiconductor light-emitting device is larger than an average inclination angle.   The surface of the concavo-convex shape of the region including the projection of the light extraction surface on at least one of the light incident surface and the light exit surface of the fluorescent portion further has a concavo-convex shape finer than the concavo-convex shape. The semiconductor light-emitting device according to claim 1, wherein   The semiconductor light emitting device according to claim 1, further comprising a light reflecting film in which a plurality of openings are formed on the light emitting surface of the fluorescent portion.   The semiconductor light emitting device according to claim 1, further comprising a plurality of light reflecting films on the light emitting surface of the fluorescent part.   The coverage of the region including the projection of the light extraction surface on the light emitting surface with the light reflecting film is larger than the coverage of the other region on the light emitting surface with the light reflecting film. Item 10. The semiconductor light emitting device according to Item 8 or 9.   The average thickness of the part of the fluorescent part facing the light extraction surface of the semiconductor light emitting element is thicker than the average thickness of the other part of the fluorescent part. The semiconductor light emitting device according to one item. A container having a mounting surface on which the semiconductor light emitting element is mounted, and an inclined surface that is formed obliquely with respect to the mounting surface and is provided so as to surround the mounting surface;
The end surface of the fluorescent part is formed obliquely with respect to the light incident surface, and the inclined surface of the container supports the end surface of the fluorescent part. A semiconductor light-emitting device according to claim 1.

Images