JP5052397B2 - Light emitting device and light emitting apparatus - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention can be applied to a wide range of applications, such as lighting devices for various types of small to large types using LED (Lighting Emitting Diode), display lighting devices such as advertising lights, sign lights, and liquid crystal backlights. This relates to a simple light source device.

  There have been many inventions of white light emitting systems using LEDs so far, for example, a structure based on a mixed color of light emission colors of three kinds of RGB LED chips, or a yellow phosphor such as a blue LED and YAG that emits light by excitation. A combination of these is well known. However, because the former has three narrow-band light emission and the intermediate wavelength component is small, and the latter has a small red wavelength component, the color rendering properties for all object colors are not necessarily high when it is used as illumination light. There was a problem. In order to improve it, there are not a few inventions that are configured by a combination of LEDs of a plurality of light colors and phosphors. For example, a blue LED and a yellow phosphor that emits light by excitation, and a configuration using a red LED in addition to that have also been proposed for a long time. Proposal 2 has been made. In both of these documents, color reproducibility (color rendering of red objects) is improved by strengthening the redness component, and in Document 1, color mixing is achieved by making a structure that corrects the difference in thickness between the two types of LED elements. It is said that the sex will also improve.

JP 2004-356116 A (pages 5-7, FIG. 1, FIG. 6) Japanese Patent Laying-Open No. 2006-80334 (pages 4-7, FIGS. 1-2, FIGS. 4-6)

  However, in the conventional methods described in Patent Documents 1 and 2, two types of LEDs that are point light sources are arranged in parallel in the light emitting region. For this reason, in the light emitting region, the two colors of the emitted light are not sufficiently mixed and are spatially color separated and are recognized as color unevenness on the light emitting part, or when the irradiation surface is irradiated with the light, the space is obtained. There is a problem that uneven color occurs. In Reference 1, the color mixing property in the resin is improved by adjusting the height of the two types of LED elements shown therein, but two types of LEDs having greatly different emission wavelengths are arranged in parallel. The spatial separation image of the two light colors with the LED chip as the light emission center cannot be sufficiently canceled while maintaining the light emission efficiency.

  Therefore, especially when used in lighting applications, even with a light source that seems to have good color rendering properties in terms of the emission spectrum, color unevenness due to this structure often appears on the object to be illuminated, and the quality is not necessarily high. It could not be said that high lighting was realized. Further, when a lens system is used for light projection or the like, the point light source images having greatly different wavelengths are often projected on the illuminated surface and are often recognized as uneven color. On the other hand, in order to reduce such color unevenness in the device configuration, there is often a means of thickening the sealing resin layer mixed with the phosphor or providing a thick diffusing material as a color mixing means as shown in Reference 2. However, there are problems that it is difficult to reduce the thickness of the device and that the light emission efficiency is lowered.

  An object of the present invention is to solve the above-described problems, and to obtain a light emitting device and a light emitting apparatus that can cope with thinning with excellent color rendering or color reproduction with excellent spatial color mixing and little color unevenness. is there.

A light emitting device according to the present invention is mounted and disposed in a housing having a cavity formed therein, a blue LED chip emitting a first light emission wavelength mounted and disposed approximately in the center of the cavity, and a peripheral portion of the cavity. A red LED chip that emits a second emission wavelength different from the first emission wavelength; a surface cover that is disposed on an upper surface of the housing and has a light emission opening as a light exit at the center; and the cavity A wavelength conversion material that is provided on the inner side or near the outer side of the light emitting opening and that excites and emits light according to the light emitting wavelength of the blue LED chip, and is lowered from the end of the light emitting opening of the surface cover toward the cavity. Only the blue LED chip is mounted and disposed in the cavity region surrounded by the vertical line, and only the blue LED chip is sealed with a translucent resin material. And further sealed with a sealing resin made of a light-transmitting resin material so as to widely cover the red LED chip and the sealed blue LED chip, and the blue LED chip was sealed The refractive index of the sealing resin is larger than the refractive index of the sealing resin sealing the red LED chip.

  According to this invention, the light source light of the second LED chip is not directly emitted, but is diffused around the rear surface of the front cover and emitted from the front cover light emitting opening through the translucent material. When the light emitting component of the second LED chip is added to almost the entire space in the sealing resin to the light color produced by the phosphor, a light emitting device with good color mixing can be obtained when the light emitting surface is directly expected. . In particular, when the second LED chip has a strong reddish light color, the overlap region between the light emission distribution and the standard relative luminous efficiency curve is small and the visible efficiency is low in the first place. Even in the case where the direct component is suppressed and diffused light (or indirect light) is frequently used, the light emission efficiency of the entire apparatus is hardly lowered. Therefore, it is possible to obtain a high color rendering device capable of maintaining a high luminous efficiency with good color mixing and little color unevenness.

Embodiment 1 FIG.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 (b) shows a side sectional view of the light emitting device, and the first LED chip 1 having the first emission wavelength and the second LED chip having the second emission wavelength in the device casing 5 and the cavity 7 in the casing. 2 is implemented. Hereinafter, the first LED chip 1 is a blue LED chip that emits about blue light having a peak wavelength of about 450 to 470 nm, and the second LED chip 2 is a red LED chip that emits about red light having a peak wavelength of about 600 to 700 nm. This will be described as an example used. Although not shown in the figure, a conductive path is formed in or around the cavity in the casing, and after the face-up LED chip is die-bonded on the cavity, wire bonding is performed so that the LED can be energized. . Note that the LED chip may be of a flip chip type. In that case, the LED chip is connected to the conductive path with a metal bump or the like, or once mounted on the submount and then connected to the wire bond.

  The device casing is made of ceramic, metal, heat-resistant resin, or a ceramic material or glass epoxy material made of a metal or other highly heat-conductive material from the cavity to the back of the casing. With this configuration, heat generated from the LED can be efficiently transmitted to the outside, and a light-emitting device with little output decrease due to temperature can be obtained even when a light-emitting device with a large electric input is realized. Further, the inner surface of the cavity 7 is formed as a highly diffusive or specular reflective surface such as coating, plating, vapor deposition, etc. in order to avoid light absorption, or is made of an alumina ceramic substrate having good heat dissipation and good reflection characteristics.

  Here, two types of LED chips mounted on the cavity are sealed with a light-transmitting sealing resin 3 such as silicone, and the efficiency of extracting light from the chips is enhanced simultaneously with the protection of the chips. In FIG. 1, two types of LED chips are sealed with the same sealing resin 3, but the second LED chip emitted light diffusely reflected on the back surface of the surface cover and the cavity 7 having the characteristics described later is sealed. While the light propagates widely in the resin, the light emitted to the side of the first LED chip emitted light propagates in the sealing resin. Therefore, the effect of increasing the color mixing effect of the two colored light beams inside the sealing resin is obtained.

  Further, a fluorescent sheet 4 that emits and emits light according to the emission wavelength of the first LED chip 1 is mounted on the top of the sealing resin 3, and the upper surface thereof is covered with a surface cover 6 provided with a light emitting opening 8. Here, only the first LED chip 1 is mounted and disposed in a cavity region surrounded by a perpendicular line extending from the light emitting opening end of the surface cover 6 on the surface of the apparatus housing to the cavity side. In addition, a configuration example in which a light distribution control lens is mounted as the light control member 9 outside the apparatus. The surface cover 6 corresponds to the upper surface portion of the housing, but is formed of a material such as resin, ceramic, or metal. At least the back side of the front cover 6 is formed as a highly reflective surface having a diffusive or specularity like the inner surface of the cavity described above in order to reduce the light loss and efficiently diffuse and utilize the LED light on the cavity side.

  The fluorescent sheet 4 is separately prepared as a material of about several tens of μm to several mm in which a phosphor is mixed in a translucent resin such as silicone, and is attached thereto. Since the phosphor is configured using a material that exhibits a light color such as yellow-green, yellow, or orange that is excited by the emission wavelength of the first LED chip (blue LED) 1 (for example, YAG, silicate, etc.), Wavelength conversion is performed to a yellowish light color by the light emitted from the first LED chip emitted from the inside of the sealing resin. At this time, if the phosphor in the phosphor sheet is composed of one having no wavelength conversion with respect to the emission wavelength of the second LED chip (red LED) 2 or having a small conversion amount, the LED itself emits light. It simply has an irregular reflection effect on light, and diffuses and transmits through the translucent region of the main sheet material. Here, the surface of the sheet may be processed to have minute irregularities, and in that case, a light diffusion effect can be provided on the surface of the fluorescent sheet 4.

With such a configuration, it is possible to obtain white light of approximately the light emission color of the first LED chip 1 (blue), the light emission color of the second LED chip 2 (red), and a mixed color of approximately yellow that has undergone fluorescence conversion. Since this emission wavelength has a strong reddish component as compared with white by the conventional blue LED + yellow phosphor system, it becomes colored light with excellent red reproducibility. Further, since the white light is configured such that the light emission image of the red LED cannot be directly seen, it is not recognized as color separation of red and blue point light sources having different wavelengths at least as in the conventional example. In addition, the white light emitting area of the blue LED + yellow phosphor centered around the center of the cavity is overlaid with the red wavelength approximately through the sealing resin, resulting in a spatially good color mixing effect. become.
In particular, when the second LED chip 2 has a strong reddish light color (for example, a light emission distribution with a peak of 600 to 700 nm and a half-value width of about 20 nm), there is little overlap area between the light emission distribution and the standard relative luminous sensitivity curve. Visible efficiency is low. On the other hand, the combined light of the first LED chip 1 and the light obtained by wavelength conversion of the first LED chip 1 has a large area overlapping with the standard relative luminous sensitivity curve, and becomes a dominant factor with respect to the light emission efficiency of the present device configuration. Therefore, even when the direct component of the second LED chip 2 is suppressed and a large amount of diffused light (or indirect light) is used as in the present configuration, the device emission efficiency is remarkably increased by ensuring a large light emitting aperture area. The decrease can be suppressed and maintained high. Therefore, it is possible to obtain a high color rendering device capable of maintaining a high luminous efficiency with good color mixing and little color unevenness.

FIG. 1A shows a configuration example in which the outer shape of the top surface of the light emitting device casing of this configuration is a quadrangle and the opening is a circle. In FIG. 1 (a), the second LED chip 2 is arranged at the four corners of the housing 5. As another configuration example, the second LED chip 2 is circular as shown in FIG. It is good also as a structure arrange | positioned circularly along. In any configuration, direct light emission from the second LED chip 2 can be prevented, and the light diffused in the space between the back surface cover and the cavity is mixed with the emitted light of the first LED chip 1. Since the alignment is good, a light source device with good color mixing can be obtained.
In addition, this embodiment and the form demonstrated below do not restrict | limit the difference in chip size and shape of 1st LED and 2nd LED. For example, a large chip (1 mm ² class) with high output is used for the first LED, and a small chip (0.3 mm ² ) is used for the second LED in consideration of device compactness and light diffusibility (uniform emission intensity in the opening). Class) and middle size chips (middle area between small and large). In particular, considering the uniform emission intensity of the second LED, it is possible to mount a plurality of second LEDs with a higher spatial density and to use them while reducing the input power.

  Hereinafter, different forms are shown in the configuration of the wavelength conversion material. In FIG. 3, the surface of the first LED chip 1 is arranged by applying or coating a material obtained by mixing a phosphor in a translucent bind resin or the like as a fluorescent material 11 on the chip. In this configuration, the wavelength of the first LED chip emission light (blue light) is converted in the sealing resin, and the blue light, the converted light, and the second LED chip emission light are mixed. FIG. 4 shows an example in which the phosphor 12 is mixed in the sealing resin as another configuration example. In this configuration, the phosphor is a diffuse reflector having no wavelength conversion function when viewed from the second LED emission light, and can promote the diffusion of the second LED chip emission light inside the sealing resin, resulting in light emission with good color mixing. Obtainable.

  Moreover, the shape of the cavity 7 is good also as a shape which changed the installation height of the installation surface of the 1st LED chip 1 and the installation surface of the 2nd LED chip 2 like FIG.5 and FIG.6. FIG. 5 shows an example in which the installation surface of the second LED chip 2 is a recess 13, and in FIG. 6, the installation surface is a projection 14 and the installation height is changed. In FIG. 5, the red light of the second LED chip 2 is sufficiently diffused in the recess and proceeds in the sealing resin. On the other hand, in FIG. 6, since the resin thickness is thick around the first LED chip emission light (blue light), the degree of light diffusion in that region is high, and the second LED chip emission light is spread throughout the cavity. It becomes the composition added. Accordingly, even in the case of these configurations, a light emitting device with good color reproducibility or high color rendering can be obtained.

Further, as shown in FIG. 7, the first LED chip 1 is sealed with the first LED sealing resin 20, and the sealing surface of the first LED sealing resin 20 is used as a boundary surface with the second LED sealing resin 21. You may comprise so that sealing may be performed. Here, for example, by making the refractive index of the first LED sealing resin 20 larger than that of the second LED sealing resin 21, partial reflection occurs at the boundary surface of the first LED sealing resin 20, There is an effect that light diffusion proceeds in the first LED sealing resin. Further, since the refractive index change of the peripheral member including itself as viewed from the first LED chip 1 is converted stepwise from large to small, a large amount of light can be extracted from the first LED chip 1. Further, after the first LED chip 1 is sealed with the first LED sealing resin 20 as shown in FIG. 8, a translucent material 16 is installed on the upper surface so as to be positioned in the middle of the second LED chip 2, The LED chip 2 may be configured to be sealed. In this case, since the light once incident on the translucent material 16 is likely to be partially totally reflected at the translucent material interface, the translucent material is used. The color mixing property of the light emitted through 16 is improved.

  Further, as shown in FIG. 9, a dam is formed of a light-transmitting or diffusing resin so as to surround the first LED chip 1 group in a flat cavity, and the second LED chip 2 is made liquid dripping using the dam. Then, the entire sealing region of the first LED chip 1 and the second LED chip 2 may be sealed. In this configuration, since the diffusion effect is once enhanced in the sealing region of the second LED chip 2 and the diffused light is propagated into the first LED sealing resin 20, light emission with good color mixing can be obtained. In addition, the second LED sealing resin 21 uses a resin whose refractive index is higher than that of the sealing resin that seals the whole, so that part of the light emitted from the second LED chip is entirely between the second LED sealing resins. As a result, the light diffusibility in the resin increases. As a result, the second LED chip emission light and the first LED chip emission light having high diffusibility are spatially added, so that the color mixing property is improved.

  As described above, the first LED chip 1 is an LED having a light emission wavelength in a blue region, the second LED chip 2 is an LED having a light emission wavelength in an orange or red region, and light is emitted according to the light emission wavelength of the first LED chip 1. By configuring the wavelength conversion material to be a material containing at least green and yellow light-emitting components, it is possible to achieve white light with good color mixing and excellent color reproducibility of reddish objects. . Further, the first LED chip 1 is made of ultraviolet light or near ultraviolet light, and the wavelength conversion material is made of a material mixed with phosphors such as blue, green, yellow, and red to be excited thereby, and further strong in a specific wavelength range according to the purpose. By using the second LED chip 2 that realizes the emission intensity, it is possible to create light with good color mixing that improves the color rendering (color reproducibility) of an object having a specific object color.

  Furthermore, the triangular area formed by the straight line connecting the chromaticity points of the main wavelength of each of the first LED chip 1 and the second LED chip 2 and the wavelength conversion material has a color temperature of about 5000 K or less in the JIS illumination light color area. It is configured to include a warm white region or a light bulb color region. As shown in FIG. 25, for example, in the light emitting device having the configuration using the first LED chip 1 (blue), the phosphor (yellowish green), and the second LED chip 2 (red), the inside of a triangle connecting approximately three points abc in the figure. Can be produced. In this case, it is possible to achieve a light bulb color and warm white even by mixing two colors connecting a and b (spectrum has no emission wavelength component of the second LED chip 2 emitting light in the red region in FIG. 26, and the blue region and the yellow region) However, considering the color rendering properties, the standard light source in the color temperature region below 5000K is the A light source (FIG. 26 shows a spectrum example of the 3000 K A light source). Therefore, in the spectrum obtained by the mixed color connecting a and b, the deviation from the standard light becomes large. The color rendering of white by the two-color mixture (equivalent to the conventional blue LED + yellow phosphor) has an average color rendering index Ra of Ra≈70, and a special color rendering index R9 showing red reproducibility is about R9≈-10. .

Therefore, by configuring so as to add the second LED chip emission light (point C), a light color having a reddish intensity as shown in the color mixture example of FIG. 26 can be obtained. The white light in this example has a high average color rendering property of Ra.apprxeq.91 and a red color rendering property of R9.apprxeq.97, which is particularly good for lighting applications. Therefore, by using the second LED chip emission light, the material is selected so that the three abc points in FIG. 25 include warm white and at least a part of the light bulb color region, so that the color rendering property is excellent and the color mixing property is low. White color can be realized.
In other JIS illumination areas, the color rendering standard light is D65 because the color temperature is approximately 5000K or higher. In this case, even in the conventional two-color mixture of blue LED + yellow phosphor that connects the points ab in FIG. 25, the relative wavelength intensity is relatively close to the standard light (intensities in the short, medium, and long wavelength regions). Therefore, it is possible to realize a light color having a color rendering index that has a relatively high value for Ra.apprxeq.

The description up to this point has been made with the configuration using only the fluorescent material that emits excitation light according to the emission wavelength of the first LED. However, the second LED emits light inside the light emitting device or near the outside of the light emitting opening. You may use the structure of carrying out excitation light emission by a wavelength. For example, the second LED chip sealing resin is mixed, the second LED chip is coated, and the first LED chip excitation phosphor is mixed with a fluorescent sheet to be bound. With such a configuration, a wavelength longer than that of the second LED light emission component is usually obtained as the second LED excitation light emission wavelength component, but the light quality and light emission efficiency are improved by continuous wavelength component using the component, It is possible to achieve the desired high color rendering.
Further, for the purpose of enhancing the light diffusibility in the sealing resin, a minute translucent filler such as silica beads or titanium oxide may be mixed. Mixing increases the proportion of diffused light in the device, so that a color mixing effect can be obtained, and depending on conditions, it has the effect of increasing luminous efficiency. In addition, application of these fluorescent substance corresponding to 2nd LED chip and a translucent filler is not restricted to the range of this embodiment, For example, it can also apply in the form demonstrated below.

Embodiment 2. FIG.
Hereinafter, other embodiments of the present invention will be described with reference to the drawings. FIG. 11B shows a side sectional view of the light emitting device, in which the first LED chip 1 having the first emission wavelength is mounted and sealed in the device housing 5 and the cavity 7 in the housing. In addition, the second LED chip 2 is mounted and arranged around the opening on the back surface of the front cover 6 and is arranged so that the light emission direction faces the cavity 7 side. Further, a fluorescent sheet 4 that emits and emits light according to the emission wavelength of the first LED chip 1 is mounted on the upper part of the sealing resin, and the upper surface thereof is covered with a surface cover 6 provided with a light emitting opening 8. At this time, the first LED chip 1 is mounted and arranged only in a cavity region surrounded by a perpendicular line extending from the light emitting opening 8 on the surface cover 6 of the light emitting device toward the cavity 7. Here, the configurations and surface characteristics of the cavity 7 and the surface cover 6 are the same as those described in the first embodiment. FIG. 11A shows a top view of a configuration example in the case where the upper surface outer shape of the light emitting device housing 5 of this configuration is a quadrangle and the opening is a circle. In this figure, the second LED chip 2 is arranged at the four corners of the housing 5. As another configuration, it is also possible to arrange the second LED chip 2 in a circular shape along the circular opening as shown in FIG.

Moreover, in such a structure, you may make it comprise the thickness of the fluorescent sheet 4 to the sealing height of the 2nd LED sealing resin 21 grade. The amount of phosphor to be contained in the phosphor sheet is determined to some extent by the desired white chromaticity, but the content per unit volume is reduced by increasing the sheet thickness. Therefore, by setting the sheet thickness to about the sealing height of the second LED sealing resin 21, the light emitted from the second sealing resin 21 and repeatedly subjected to diffuse reflection on the back surface of the cavity 7 and the front cover 6 is efficiently fluorescent sheet. 4 is incident. Furthermore, since the probability that the light hits the phosphor is lowered, color mixing of the light emitted from the first LED chip and the light whose wavelength is converted in the fluorescent sheet is performed through the fluorescent sheet 4 without significantly reducing the translucency. Thus, a light emitting device with good color mixing can be obtained. In addition, the incident efficiency of light emitted from the second LED chip is further improved by forming the surface of the side cross section of the sheet so as to be as uneven as possible.
Although not shown, the fluorescent sheet 4 is a thin material, and a translucent material is laid on the top (a fine unevenness may be added to the surface), and a thin diffusion is made on the surface of the translucent material. Even in a configuration in which sheets are arranged, a good color mixing effect can be obtained.

  At this time, the second LED chip 2 may be sealed as shown in FIGS. 11 and 12, but each LED chip may be sealed. However, as shown in FIG. The cross section may be sealed in a semicircular shape. With this configuration, the second LED chip emission light is widely guided into the sealing resin, so that the substantially uniform second LED chip emission light is directed along the vicinity of the opening and toward the center of the cavity. As a result, a good color mixing effect can be obtained in the fluorescent sheet.

  Further, as shown in FIG. 14, a configuration in which a fluorescent material is disposed on the top of the first LED chip 1, a configuration in which a phosphor is mixed inside the first LED sealing resin 20, and a configuration in FIG. In addition, spatial color mixing can be improved even with a configuration in which a translucent material is installed on top of the first LED sealing resin 20. The first LED sealing resin 20 in FIG. 14 and FIG. 15 has a shape with a flat surface. However, the shape of the first LED sealing resin 20 is raised as shown in FIG. It is good also as a structure which touches an edge part. With such a configuration, the second LED chip light emitted directly from the light emitting opening 8 can be eliminated, and once diffused in the first LED sealing resin 20 to emit light, a good color mixing effect can be obtained.

Further, as shown in FIG. 18, the air layer region generated between the surface side horizontal surface of the surface cover 6 and the bottom surface of the cavity 7 is configured to be sealed or filled with a translucent resin 50. In FIG. 18, the intermediate layer of the first LED sealing resin 20 and the second LED sealing resin 21 is filled with resin, but by using this configuration, for example, multiplexing between the second LED sealing resin and the cavity reflection surface is possible. Light reflection loss can be reduced, and the total reflection ratio generated at each sealing resin interface can also be suppressed. Therefore, the amount of light loss caused by the refractive index difference in the light emitting device can be reduced, and a device with high light emission efficiency can be obtained. Here, if the refractive index of the translucent resin 50 is a characteristic value close to the refractive indexes of the first sealing resin and the second sealing resin, light loss at the resin interface can be extremely reduced.
Furthermore, by using this configuration, the first LED emission light, the second LED emission light, and the fluorescence conversion light by the fluorescence conversion material 11 travel (scatter) in the direction through the translucent resin. Therefore, as a result, the color mixing property as the light emitting device can be improved. From such a viewpoint, the translucent resin 50 may be configured to partially fill the upper portion of the first LED sealing resin and the opening side region of the second LED sealing resin, for example.

Embodiment 3 FIG.
FIG. 19B is a side sectional view of another light-emitting device of the present invention. The first LED chip 1 is mounted and disposed at the substantially center of the LED mounting substrate 32, and the sealing side face is substantially vertical with respect to the substrate 32. The first LED sealing body 30 sealed with a translucent sealing resin so as to have the second LED chip 2 mounted and sealed in the vicinity of the side surface of the first LED sealing body 30, A reflection plate 35 whose tip is erected toward the first LED sealing body so as to form a light-emitting opening that is an exit of light in the portion, and a cavity constituted by the substrate 32 and the reflection plate 35 A wavelength conversion material that excites and emits light by the emission wavelength of the first LED chip 1 is provided inside or near the outside of the light emitting opening. Further, only the first LED chip is mounted and disposed in the cavity region formed by a perpendicular line extending from the light emitting opening end portion of the reflection plate 35 toward the cavity side. With this configuration, a part of the light emitted from the second LED chip is directly incident on the first LED sealing body 30, and another part is reflected by the reflecting plate 35 and is similarly sealed by the first LED. Incident on the body 30. And it has the effect that 1st LED emitted light and 2nd LED chip emitted light are mixed favorably within the 1st LED sealing resin which comprises the 1st LED sealing body 30. FIG.
Here, the LED mounting substrate is composed of a thermally conductive substrate based on ceramic or metal (aluminum, copper base). In the case of ceramic, the one having a mounting pattern formed on the surface thereof and the metal substrate having a mounting pattern or conductive pattern formed by surface insulation processing are used. Further, the reflecting plate material is composed of at least an inner surface having a highly reflective mirror surface or diffusibility.

Here, the surface of the first LED sealing body 30 is a flat surface, and the wavelength conversion material is disposed on the surface of the first LED sealing body 30 as a fluorescent sheet 4 in which the phosphor is resin-bound. The wavelength of light emitted through the conductive sealing resin is converted in a wide fluorescent sheet region on the entire surface of the first LED sealing resin. The wavelength conversion material may be mixed in the sealing resin as in the other embodiments described above, or may be formed by applying or spraying a binding material containing the same on the surface of the first LED chip 1.
Furthermore, you may comprise so that the fine unevenness | corrugation 33 may be provided in the surface of the 1st LED sealing body 30 like a figure. This configuration has the effect of diffusing the emitted light of the first LED chip 2 and the effect of propagating the second LED chip emitted light while diffusing the emitted light of the first LED chip, resulting in improved color mixing.

FIG. 20B is a side sectional view of another light emitting device of the present invention. The basic configuration is mounting the LED mounting substrate 32 on which the first LED chip 1 having the first emission wavelength is mounted, and the second LED chip 2 having an emission wavelength different from the first emission wavelength located around the emission opening. And a reflecting plate 35 extending from the end of the surface cover to the LED substrate so as to cover the second LED.
The first LED chip 1 is mounted almost at the center of the LED mounting substrate 32, and the first LED chip 1 is sealed with a translucent resin as the first LED sealing body 30 so as to have a rising side surface with respect to the substrate. . Further, the surface cover 6 is positioned approximately on the end side of the first LED sealing body 30 so that the radiation direction of the second LED chip 2 and the radiation direction of the first LED chip 1 are opposite in the vertical direction. Arranged to be.
Here, there is no gap between the tip of the reflecting plate 35 and the LED mounting substrate 32 so that no light leakage occurs. Here, the material of the reflecting plate 35 and the LED mounting substrate 32 is made of the same material as described in FIG. 18, but the reflecting plate 35 and the LED mounting substrate 32 are integrated with, for example, a metal plate, and necessary surface processing is performed. You may comprise with such a member.
With this configuration, the light emitted from the first LED chip 2 is diffused and propagated in the first LED encapsulating body under the light control effect of the fine unevenness 33 shape on the surface, and emitted to the surface, and also reflected on the reflector surface. Similarly, the second LED chip light emitted into the first LED sealing resin also has the effect of diffusing and propagating in the first LED sealing body 30 and emitting light on the surface thereof. There is an effect that two kinds of light within 30 are added, and the color mixing property is improved.
In addition, in the structure of FIG. 19, FIG. 20, although it showed in the example at the time of forming the 1st LED sealing body 30 in the square, for example, it is set as the circular shape like the structure of FIG. Depending on the shape, the second LED may be arranged. Further, in the configuration of FIG. 19, the shape of the opening surrounded by the top surface of the reflector and the surface cover 6 in FIG. 20 may be configured to be circular or polygonal according to these shapes, and such a configuration meets the needs. Thus, a light emitting device having an arbitrary opening shape can be realized.

Embodiment 4 FIG.
In the apparatus configuration of the embodiment described above, the LED light source can be configured even if an LED package is used so that the arrangement relationship of the two types of LED chips is maintained as it is. Hereinafter, an example in which at least one of the light emitting bodies of the first LED chip 1 and the second LED chip 2 is constituted by an LED package will be shown. FIG. 21 shows an example in which the second LED chip 2 is used as the second LED package 41 and a side view type package is used. FIG. 21 shows an example in which the mounting surface is mounted on the back side of the front cover, and FIG. 22 is configured to be mounted on the cavity so that the light emission direction of the package faces the fluorescent sheet 4 side. Yes. In the side view package, light emitted from the side view package efficiently propagates through the fluorescent sheet, so that a light emitting device with very good color mixing can be obtained.

  FIG. 23 shows an example in which the first LED chip 1 is also the first LED package 40 and the fluorescent sheet 4 is used as the wavelength conversion material, and FIG. 24 shows white light emission that includes the first LED chip 1 and the wavelength conversion material. It is an example configured as a package 42, and any of them can obtain a spatial color mixing effect. Here, between the installations of the plurality of LED packages emitting the second emission wavelength, a configuration in which they are closed with a highly reflective surface so as not to leak light is adopted. With such a structure, there is no light leakage between packages, and a light-emitting device with high light emission efficiency can be obtained by using a high-reflectance material as an inter-installation material. Note that existing products can be used for the second LED package 41, the first LED package 40, and the white light emitting package 42 shown in the above example.

Embodiment 5 FIG.
Further, it is possible to realize a light emitting apparatus as shown in FIGS. 10 and 16 by using this apparatus as a light source. In FIG. 10, the light-emitting device 23 is configured by using the light-emitting device 22 of FIG. 1 and in FIG. 16 using the light-emitting device 25 of FIG. A portion of the light emitting device 23 excluding the surface cover portion of the light emitting device is used as a light source element, and a device surface cover 24 serving as the surface cover 6 in FIG. Prepared and assembled. Here, at least a portion corresponding to a region covering the second LED chip 2 of the instrument surface cover 24 has high reflectivity. In the configuration of FIG. 16, the second LED chip 2 is mounted on the surface cover side that has been subjected to wiring processing in advance, so that the light emitting device 23 can be easily assembled by simply combining it with the device housing body. It is possible. At this time, the front cover 24 is made of a material having high thermal conductivity, and the light emitted from the second LED chip 2 can be efficiently emitted to the outside, or can be emitted to the outside through the housing, thereby improving luminous efficiency. An excellent light emitting device 23 can be obtained.

  Moreover, although the structural example provided with the optical control member outside the light emitting device has been described so far, the light distribution control may be performed with a simple configuration in which an integrated optical control member is provided outside the light emitting device. The optical control member is composed of an optical lens, an optical film, an optical sheet, and the like that control the light distribution and spectral transmittance of the light emitting device according to the required light quality. Furthermore, it is possible to increase the efficiency and extend the service life by adopting a configuration in which the housing of the appliance is formed of a highly heat conductive material and heat radiation of the LED heat is promoted by attaching a heat radiating fin or the like on the back surface.

  In addition, the light-emitting device or light-emitting device of the present invention described above is provided with a light detection member such as a photodiode or a color sensor, or a temperature detection member such as a thermistor, and the electric light according to the light amount or temperature of the device or the device. An external terminal that performs output may be provided. With this configuration, it is possible to detect the light output state and temperature state of the light-emitting device or fixture, to estimate whether the target light output has been reached, and to control the light state by providing a control calculation unit etc. Is possible.

  In addition, in the light emitting device or the light emitting apparatus capable of monitoring the state of the light quantity and temperature as in this configuration, the function for setting the thresholds related to the state quantities and the difference between the set threshold and the state quantities are calculated. And a function for cutting off the supply of power when the state quantity reaches a set threshold value. In addition to the above configuration, by providing a fuse and an LED for notification, for example, when the light state becomes 70% or 50% of the initial luminous flux, the lifetime of the device is estimated and the fuse is cut and the light is completely extinguished. It is possible to prompt the user to check or replace the apparatus or the instrument by controlling the state or making the notification LED blink.

  As described above, the present invention provides a light-emitting device that can cope with low color temperature white light emission with good color rendering properties and has little color unevenness on the light-emitting portion and the irradiated surface, and a light-emitting device using the same. Therefore, it can be used for a wide range of applications such as small to large luminous flux illumination and liquid crystal backlight regardless of indoor or outdoor installation.

It is the upper side figure and side sectional drawing of the light-emitting device of this invention. It is a top view of the light-emitting device of other composition of the present invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is an example of 1 structure of the light-emitting fixture using the light-emitting device of the structure of FIG. It is the upper side figure and side sectional drawing of the light-emitting device of the other structure of this invention. It is a top view of the light-emitting device of other composition of the present invention. It is a top view of the light-emitting device of other composition of the present invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is an example of 1 structure of the light-emitting fixture using the light-emitting device of the structure of FIG. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of the light-emitting device of the other structure of this invention. It is the upper side figure and side sectional drawing of the light-emitting device of the other structure of this invention. It is the upper side figure and side sectional drawing of the light-emitting device of the other structure of this invention. It is side sectional drawing of one light-emitting device of this invention using a LED package. It is side sectional drawing of the light-emitting device of the other structure of this invention using an LED package. It is side sectional drawing of the light-emitting device of the other structure of this invention using an LED package. It is side sectional drawing of the light-emitting device of the other structure of this invention using an LED package. It is the figure which showed the example of the color mixing area | region which consists of two types of LED and fluorescent substance in the light-emitting device of this invention. It is an example of the emission spectrum of the light-emitting device of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 1st LED chip, 2 2nd LED chip, 3 sealing resin, 4 fluorescent sheet, 5 housing | casing, 6 surface cover, 7 cavity, 8 light emission opening part, 9 light control member, 11 fluorescent material, 12 fluorescent substance, 13 Concave part, 14 Convex part, 16 Translucent material, 20 1st LED sealing resin, 21 2nd LED sealing resin, 22 Light-emitting device of FIG. 1, 23 Light-emitting device, 24 Device surface cover, 25 Light emission of FIG. Device, 30 1st LED sealing body, 32 LED mounting substrate, 33 fine unevenness, 35 reflector, 40 1st LED package, 41 2nd LED package, 42 white light emitting package, 50 translucent resin.

Claims (34)

A housing with a cavity formed inside;
A blue LED chip emitting a first emission wavelength mounted and disposed approximately in the center of the cavity;
A red LED chip that emits a second light emission wavelength different from the first light emission wavelength, which is mounted and arranged at the periphery of the cavity;
A surface cover disposed on the upper surface of the housing and having a light emitting opening as a light exit at the center;
A wavelength conversion material that is provided on the inside of the cavity or in the vicinity of the outside of the light emitting opening, and that emits excitation light according to the light emission wavelength of the blue LED chip,
Only the blue LED chip is mounted and disposed in a region of the cavity formed by surrounding a perpendicular line that extends downward from the light emitting opening end of the surface cover toward the cavity,
Only the blue LED chip is sealed with a sealing resin made of a translucent resin material, and further made of a translucent resin material so as to cover the red LED chip and the sealed blue LED chip widely. Seal with sealing resin,
The light emitting device, wherein the sealing resin encapsulating the blue LED chip has a refractive index higher than that of the sealing resin encapsulating the red LED chip.   The wavelength conversion material is a sheet-like material in which a phosphor that is excited and emitted by the emission wavelength of the blue LED chip is bound to a translucent resin, and at least the surface cover rear surface side so as to cover the entire light emission opening of the surface cover Alternatively, the light-emitting device according to claim 1, wherein the light-emitting device is disposed on a surface side.   The light emitting device according to claim 1, wherein the wavelength conversion material is a material obtained by mixing a phosphor binding material such as a translucent resin and a phosphor, and is provided on a surface of the blue LED chip.   The light emitting device according to claim 1, wherein the wavelength conversion material is a phosphor mixed in the sealing resin.   5. The light emitting device according to claim 1, wherein an installation surface of the blue LED chip is different from an installation surface of the red LED chip. A housing with a cavity formed inside;
A blue LED chip that emits a first emission wavelength mounted and arranged at approximately the center of the cavity;
A surface cover disposed on the upper surface of the housing and having a light emitting opening as a light exit at the center;
A wavelength conversion material that is provided on the inside of the cavity or in the vicinity of the outside of the light emitting opening, and that emits excitation light according to the light emission wavelength of the blue LED chip,
Only the blue LED chip is mounted and disposed in a region of the cavity formed by surrounding a perpendicular line extending from the light emitting opening end of the surface cover to the cavity side,
Further, a red LED chip that emits a second light emission wavelength different from the first light emission wavelength around the light emission opening on the back surface of the front cover has a radiation direction opposite to the radiation direction of the blue LED chip. So as to implement and arrange
A light-emitting device, wherein the blue LED chip and the red LED chip are sealed with a translucent resin material.   The wavelength conversion material is a sheet-like material in which a phosphor is bound to a translucent resin material, and is disposed on the back surface side or the front surface side of the front cover so as to cover at least the entire light emitting opening of the front cover. The light emitting device according to claim 6.   The sheet material has a thickness equal to or higher than the height of the red LED chip sealing resin, and is arranged on the upper surface of the blue LED chip sealing resin so that the red LED chip sealing resin body is positioned in the vicinity of the sheet side surface. The light-emitting device according to claim 7.   The light emitting device according to claim 6, wherein the wavelength conversion material is a material obtained by mixing a phosphor binding material such as a translucent resin and a phosphor, and is provided on a surface of a blue LED chip.   The light emitting device according to claim 6, wherein the wavelength conversion material is a phosphor mixed in a sealing resin for sealing the blue LED chip.   The plurality of red LED chips mounted and arranged near the light emitting opening on the back surface of the front cover are continuously sealed with a translucent resin so as to follow the shape of the light emitting opening. The light emitting device according to any one of the above.   The sealing resin for sealing the blue LED chip is formed to be convex toward the outside of the light emitting opening, and the side surface of the convex portion is configured to be in contact with the entire end of the light emitting opening. The light emitting device according to any one of claims 6 to 11.   The air layer formed between the surface side horizontal surface of the surface cover and the bottom surface of the cavity is sealed or filled with a translucent resin in a part or all of the air layer. The light-emitting device of description. An LED mounting board;
A blue LED chip that emits a first emission wavelength, which is mounted and arranged at substantially the center of the substrate;
A blue LED sealing body having a rising side surface with respect to the substrate and sealing the blue LED chip with a translucent resin;
A red LED chip emitting a second light emission wavelength different from the first light emission wavelength is mounted on the back surface and sealed with a translucent resin so as to form a light emission opening. A surface cover made of one or more members,
A reflecting plate covering the red LED chip of the front cover,
The emission direction of the red LED chip is opposite to the emission direction of the blue LED chip, and no light is generated between the tip of the reflector and the LED substrate. apparatus. The blue LED sealing body has a flat surface facing the blue LED chip,
The light emitting device according to claim 14, wherein the wavelength conversion material is formed of a fluorescent sheet in which a phosphor is bound with a translucent resin or the like, and is disposed on a flat surface of the blue LED sealing body.   The light-emitting device according to claim 15, wherein the blue LED sealing body includes fine irregularities on a back surface of the flat surface.   The light emitting device according to claim 1, wherein at least one of the light emitting bodies of the blue LED chip and the red LED chip is configured by an LED package in which an LED chip is packaged in advance.   The light-emitting device according to claim 1, wherein the blue LED chip and a wavelength conversion material that emits and emits light according to its emission wavelength are configured as a white LED package.   The light emitting device according to claim 17 or 18, wherein the red LED chip is a side view type LED package, and the light emitting direction is the direction of the blue LED chip.   The light emitting device according to any one of claims 17 to 19, wherein a space between each of the plurality of LED packages emitting the second emission wavelength is closed with a highly reflective surface.   21. The light-emitting device according to claim 1, wherein the wavelength conversion material that emits and emits light according to the emission wavelength of the blue LED chip is a material that includes at least a green or yellow light-emitting component.   The light emitting device according to any one of claims 1 to 21, further comprising a wavelength conversion material that excites and emits light to the red LED chip inside the light emitting device or in the vicinity of the outside of the light emitting opening.   The light-emitting device according to claim 1, wherein a light-transmitting filler is mixed in a light-transmitting resin material for sealing the LED chip of the light-emitting device.   24. The light emitting device according to claim 1, wherein a side surface inside the device is made of a highly reflective material.   The light-emitting device according to claim 1, wherein at least a part of the rear surface of the light-emitting device housing is made of a highly thermally conductive material such as a ceramic or a metallic material.   The triangular region that connects the chromaticity points of the main wavelengths of the blue LED chip, the red LED chip, and the wavelength conversion material with a straight line includes a warm white region or a light bulb color region in the JIS illumination light color region. The light-emitting device according to claim 1, which is configured as described above.   27. The light emitting device according to any one of claims 1 to 26, wherein a base material of the surface cover is made of a highly heat conductive material such as ceramic or metallic material.   A light-emitting apparatus comprising a plurality of the light-emitting devices according to claim 1.   29. The light emitting device according to claim 28, wherein a surface cover of the light emitting device is made of an integral material.   The light emitting device according to claim 28, wherein an external light control member is integrally formed.   31. The light emitting apparatus according to claim 30, wherein the light control member is any one of an optical lens, an optical film, and an optical sheet that control light distribution and spectral transmittance of the light emitting device. A light detection member such as a photodiode;
29. The light emitting device according to claim 28, further comprising means for performing an electrical output in accordance with a light amount of the light emitting device detected by the light detection member. Storage means storing a threshold;
33. The light emitting device according to claim 32, further comprising means for stopping the supply of electric power when the amount of light detected by the light detection member reaches a threshold value stored in the storage means. A temperature detection member such as a thermistor;
29. The light emitting device according to claim 28, further comprising means for performing an electrical output in accordance with the temperature detected by the temperature detection member.

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