CN102644864A - Light-emitting device and lighting fixture using the same - Google Patents

Abstract

The invention relates to a light-emitting device and a lighting fixture using the same. In the light-emitting device, a plurality of LEDs with different color degrees emitted from the substrate form a group. The light-emitting device has a plurality of groups. Each group comprises at least the LED emitting the white light; the distance (d1) between each group is greater than the distance (d2) between the adjacent LEDs in the group. Therefore, compared with the condition that preset number of the LEDs are intervally arranged on the substrate, the colored lights from the LEDs in each group are easy to be color-mixed so that the hue unevenness of the emitted lights is difficult to happen. Besides, the LED with the white light is contained so that the white light without hue unevenness is easy to get.

Description

Light-emitting device and lighting fixture using the light-emitting device

technical field

The present invention relates to a light-emitting device and a lighting fixture using the light-emitting device, in which a plurality of LEDs (Light Emitting Diodes: Light Emitting Diodes) with different light-emitting colors are mixed and irradiated.

Background technique

8( a ) to ( d ) show an example of a light-emitting device that mixes and irradiates a plurality of LEDs having different light-emitting colors. In FIGS. 8( a ) and ( b ), the light emitting device 100 is configured by mounting and arranging a plurality of LEDs 102 and 103 emitting lights of different chromaticities alternately and linearly at equal intervals of a distance dx on a substrate 101 . In this light-emitting device 100, for example, the light of two colors from the LEDs 102 and 103 for emitting arbitrary colors of R, G, and B is located at a predetermined distance h on the light-transmitting panel serving as a cover above the substrate 101. Intersect to mix the irradiation.

In addition, as such a light-emitting device, there is known a light-emitting device in which a plurality of solid-state light-emitting devices composed of LEDs and phosphors are densely arranged on a substrate, light of different luminous colors is emitted from each solid-state light-emitting device, and the light is mixed to form a solid-state light-emitting device. injection (for example, refer to Patent Document 1). In this light-emitting device, LEDs emitting light of three colors of R, G, and B are alternately arranged in a matrix at equal intervals on a substrate to obtain mixed light.

However, in recent years, as light beams from single LED elements have increased, even if the number of LED packages mounted side by side on a substrate is reduced, a desired amount of light can be obtained. On the other hand, the condition that the area of the substrate on which the LEDs are mounted must reach a certain level for heat dissipation of the LEDs has not changed. Therefore, as shown in Fig. 8(c) and (d), the number of LEDs 102 and 103 is reduced compared to the case shown in Fig. 8(a) and (b), and they are arranged at equal intervals on a substrate of the same size. Next, each LED is arranged such that the interval dy is greater than the interval dx.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2009-238729

The problem to be solved by the invention

However, as shown in FIGS. 8( c ) and ( d ), if the interval dy between the LEDs is increased, the lights from the LEDs 102 and 103 do not cross each other at the same predetermined distance h above the substrate 101 . Therefore, in a light-emitting device in which LEDs are arranged at equal intervals, light from a plurality of LEDs emitting light of different colors is less likely to mix colors, and color unevenness (Japanese: 色むら) tends to occur in irradiated light. In addition, when the light-emitting device that mixes the three colors of R, G, and B described in Patent Document 1 is used for a lighting fixture, white light cannot be irradiated unless the three colors are uniformly mixed.

Contents of the invention

The present invention was made in order to solve the above problems, and an object of the present invention is to provide a light-emitting device that mixes and irradiates light from a plurality of LEDs having different light-emitting colors, which is less likely to cause uneven hue of the emitted light and can A white light-emitting device free from color unevenness was obtained.

method used to solve the problem

In order to achieve the above object, a light-emitting device of the present invention is characterized in that a group is formed of a plurality of solid light-emitting elements that emit light of different chromaticities, the light-emitting device has a plurality of groups, and each group in the above-mentioned groups is at least The solid light emitting elements that emit white light are included, and the distance between the groups is set to be larger than the distance between the solid light emitting elements in the groups.

Preferably, in the light emitting device, each of the above-mentioned groups includes a solid light emitting element that emits incandescent light.

Preferably, in the light-emitting device, each of the above-mentioned groups includes solid-state light-emitting elements that respectively emit light of at least two chromaticities of red, blue, and green.

In this light-emitting device, each of the above-mentioned groups preferably has an optical member that mixes colors of light from each solid-state light-emitting element.

In this light-emitting device, preferably, the optical member is a reflective member that reflects light derived from the solid-state light-emitting element.

In this light emitting device, preferably, the optical member is a lens that mixes colors of light emitted from the solid light emitting element.

Preferably, in the light-emitting device, the distance between the light-emitting centers of the closest adjacent solid-state light-emitting elements in the group is within 15 mm, and the light beams of each of the above-mentioned solid-state light-emitting elements are 10 lumens to 600 lumens when they are 100% lit. .

Preferably, the light emitting device further includes a diffusing member for commonly diffusing the light emitted from each of the above-mentioned groups, and the distance between the above-mentioned groups or the solid angle of the light derived from the light-emitting group is configured such that from the above-mentioned The light emitted by the solid light emitting element is adjacent to or overlaps with each other around the projected portion on the diffusion member.

Furthermore, a lighting fixture of the present invention includes the above-mentioned light-emitting device.

Invention effect

According to the light-emitting device of the present invention, compared with the case where a predetermined number of solid-state light-emitting elements are arranged at equal intervals, the light from each light-emitting element in each group is easy to cross and mix colors, so it is possible to reduce the irradiation light of different chromaticities, and it is difficult to produce Uneven hue. In addition, since the solid light-emitting element emitting white light is included in the group, it is possible to emit white color without uneven hue.

Description of drawings

FIG. 1 is a configuration diagram of a light emitting device according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view showing an irradiation state of light from each LED of the light emitting device.

Fig. 3 is a configuration diagram when the arrangement interval of LEDs is changed between light emitting groups of the above light emitting device.

Fig. 4 is a configuration diagram of a modified example of the light emitting device.

5 is a cross-sectional configuration diagram of a light emitting device according to a second embodiment of the present invention.

Fig. 6 is a cross-sectional structural view of a modified example of the light emitting device.

7( a ) is a cross-sectional structural view of a light emitting device according to a third embodiment of the present invention, and FIG. 7( b ) is a diagram showing a projection pattern of irradiation light from the light emitting device in FIG. 7( a ) on a diffusion member. picture.

Fig. 8 (a) is a structural diagram of a conventional light-emitting device, Fig. 8 (b) is a sectional view showing the irradiation state of light from each LED of the light-emitting device of Fig. 8 (a), and Fig. 8 (c) is an enlarged view 8( a ) is a configuration diagram showing the interval between LEDs of the light emitting device, and FIG. 8( d ) is a cross-sectional view showing the irradiation state of light from each LED of the light emitting device of FIG. 8( c ).

Detailed ways

(first embodiment)

A light emitting device according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2 . As shown in FIG. 1 , the light-emitting device 1 has a substrate 2 and a plurality of LEDs 31 and 32 (solid-state light-emitting elements, collectively referred to as 3 ) that are mounted side by side on the substrate 2 and emit lights of different chromaticities. In addition, in the light-emitting device 1 , LEDs 31 and 32 constitute one light-emitting group 4 a , 4 b , and 4 c (group, generally referred to as 4 ), and each light-emitting group 4 includes at least an LED that emits white light. In addition, the light-emitting device 1 is used, for example, as a lighting fixture mounted on a ceiling with a mounting jig (not shown), or as a downlight embedded in a ceiling wall.

In this embodiment, the LEDs 31 and 32 respectively include a solid light emitting element that emits white light and a solid light emitting element that emits incandescent light (Japanese: electric ball color), and are alternately arranged along the center line 20 in the longitudinal direction of the substrate 2 . The LED mounting surface of the substrate 2 is disposed upwardly and the irradiation light is emitted upward. In addition, the solid-state light-emitting element that emits white light can be composed of a white LED or the like. The white LED is formed, for example, of a blue LED element that emits blue light and a yellow phosphor that emits yellow light when excited by light from the blue LED element. . In addition, the solid state light-emitting element which emits the light of incandescent light uses the element which converts the light of a blue LED element into incandescent light by a fluorescent substance. In addition, each LED and phosphor may be embedded in a package such as ceramics and mounted on the substrate 2 . In addition, each solid light-emitting element may be formed by mounting an LED element on a ceramic or aluminum substrate and covering it with a phosphor. At this time, multiple light colors are emitted by coating different types of phosphors on each element.

Each light-emitting group 4 includes LED31, 32 respectively, and is constructed adjacent to each other along the length direction of the substrate 2. The distance d1 between adjacent light-emitting groups 4 is set to be greater than the shortest distance between LED3 in each group 4. distance d2. Here, the distance d1 between each light emission group 4 is the distance between the light emission centers of the irradiation light which the light from each LED31 and 32 of each group 4 forms. Moreover, the distance d2 between LED31 and 32 in each light emission group 4 is the distance between the emission centers of the irradiation light of each LED3. The distance d1 between the groups may not be equal, and the same applies to the distance d2. The distances d1 and d2 can be set arbitrarily according to the shape of the installation portion where the substrate 2 is installed and the shape of the transmissive cover covering the LED 3 .

When arranging the LEDs, the distance d2 between the LEDs 31 and 32 on the substrate 2 is shorter than the distance dy between the LEDs arranged at equal intervals on the substrate of the same size shown in FIG. close to each other. Therefore, each light emitting group 4 is densely arranged on the substrate 2 according to categories, and each category is based on a combination of each color light (here, white and incandescent light) from LEDs 31 and 32 .

Moreover, the distance d2 between each LED31, 32 shall be within 15 mm, and the light flux of said LED31, 32 shall be 10-600 lumens at the time of 100% lighting. In addition, the substrate 2 uses a printed circuit board, a ceramic substrate, or the like for mounting LEDs and the like, and its shape is not limited to the illustrated rectangle, and may be circular, polygonal, or the like. Moreover, power is supplied to each LED3 via the wiring pattern on the board|substrate 2, for example by the power supply circuit (not shown) formed in the board|substrate 2. In addition, each LED31,32 can adjust the mixing ratio of the said color light by controlling the emitted light individually by a power supply circuit.

设为彼此相同，例如将覆盖发光装置1的扩散用的乳白色面板、罩面板等设为混合光的等效的出射面，根据该出射面与基板2之间的距离来确定预定的距离h。FIG. 2 shows an irradiation state of light from the respective LEDs 31 and 32 of the light-emitting groups 4 a and 4 b when the light-emitting device 1 is viewed from the side surface of the substrate 2 . In each light-emitting group 4, each LED 31, 32 is close to each other at a distance d2 from each other, so the white and incandescent lights from each LED 31, 32 intersect at a predetermined distance h above the substrate 2, forming a pattern based on The light of the above-mentioned color light is mixed and irradiated. In addition, the three-dimensional angle viewed from each emission center of the irradiation light of each LED31, 32 may be

Assuming that they are identical to each other, for example, a milky white panel for diffusion covering the light emitting device 1, a cover panel, etc. are used as an equivalent output surface of the mixed light, and the predetermined distance h is determined according to the distance between the output surface and the substrate 2 .

According to this embodiment, compared with the case where a predetermined number of LEDs 3 are arranged at equal intervals, the light from each LED 3 in each group 4 is more likely to cross and mix colors, so it is possible to reduce the irradiated light of different chromaticities, and it is difficult to generate uneven hue. Moreover, since LED3 which emits white light is included in each group 4, it can emit white color without unevenness of hue.

In addition, since the distance (d2) between the light emitting centers of each LED3 is within 15 mm, for example, if the solid angle When it is 90 degrees or more, the distance h of the intersection position of the light from LED31, 32 can be brought close to within 7.5 mm, and mixed light can be formed at a relatively low height. In addition, the light beams of the LEDs 31 and 32 are set at 10 to 600 lumens when turned on 100%, and therefore do not become less than 10 lumens when turned on, so that the irradiation becomes dark and the color light does not mix. In addition, since the lighting does not exceed 600 lumens, it is possible to avoid the situation where the mixed color cannot be distinguished due to glare due to excessively bright irradiation.

In addition, in the present embodiment, a structure in which one light emitting group includes LEDs 31 and 32 each emitting white light and incandescent light is shown, but at least one of the plurality of LEDs 3 in each group 4 emits white light. The light LED31 can be. For example, there may be two or more LEDs 31 in each group 4, or two or more LEDs 32 emitting incandescent light.

In addition, the arrangement of each LED 3 in each light emitting group 4 does not need to be arranged regularly. Thereby, also can for example as shown in Figure 3, the LED spacing of each light-emitting group 4, in the central part of the substrate 2 where heat is easy to concentrate, expand the spacing to a certain extent and evenly arrange, in the peripheral part of the substrate 2, each LED3 Configured densely by category. In this case, the LEDs 31 and 32 of the light-emitting groups 4a and 4c form a category and are densely arranged on the peripheral portion of the substrate 2, and the LEDs 31 and 32 in the group 4b in the central portion of the substrate 2 are larger than the light-emitting groups 4a and 4c. configured at intervals.

(Modification)

A modified example of the light emitting device of the above embodiment will be described with reference to FIG. 4 . In the light-emitting device 1 of this modified example, each light-emitting group 4 includes LEDs that emit light of at least two chromaticities of red, blue, and green in addition to LEDs that emit white light. . In this light-emitting device 1, the light-emitting groups 4d to 4f each include an LED 31 that emits white (W) light and LEDs 33 and 34 that emit light of each chromaticity of red (R), green (G), and blue (B). and 35.

The above-mentioned LEDs 31 and 33-35 are respectively arranged on the four vertices of the square along the center line 20 on the substrate 2 according to each light-emitting group 4, and the distance d2 between the nearest adjacent LEDs is within 15 mm, which is greater than that of each light-emitting group. The distance d1 between 4 (4d-4f) is short. Here, the light emitting device 1 is configured such that in each group 4, four LEDs 31, 33 to 35 are densely packed for each category consisting of white, red, green, and blue. Each light emitting group 4 can obtain various mixed lights by controlling the mixing ratios of white light and red, green, and blue lights. For example, when white light is obtained by each group 4, each color light of R, G, and B from LED33-35 is suppressed, and the mixing ratio of the white light from LED31 is raised. At this time, each group 4 can not generate white light by the three-color light of R, G, and B that tends to cause color unevenness due to color balance deviation, but can constitute white light only by white light from the LED 31, so it is possible to generate white light. White light without color unevenness is obtained. In addition, when the LEDs 33 to 35 can obtain white light with a good color balance of the three color lights of R, G, and B and little unevenness in hue, it can cooperate with (Japanese: multiply) the white light from the LED 31 to obtain a better color balance. Bright white light. In particular, when white is generated by RGB, the variation in chromaticity increases due to the variation of each LED package and the variation of the current flowing in each package. Therefore, by adding a part that emits white from one package, the variation suppression effect is increased. big. In addition, single colors of RGB may be seen through the light-transmitting cover, especially when the output is small, it is highly possible, but increasing the white package makes it difficult to see each single color, so the effect on appearance is also large.

(second embodiment)

A light emitting device according to a second embodiment of the present invention will be described with reference to FIG. 5 . As shown in FIG. 5, in the light-emitting device 1 of the present embodiment, each light-emitting group 4 (4a, 4b) has an optical component that mixes the light of each LED 3 (31, 32) in the above-mentioned embodiment as the optical component. , using reflector 5.

The reflection plate 5 has a concave reflector 51 disposed on the substrate 2 and constituted by a drum-shaped (Japanese: bottle-shaped) hollow rotating body, and each light-emitting group 4 (4a, 4b) is surrounded by each concave reflector 51. A reflection plate 5 is provided for each LED 3 . The reflector 5 uses the central axis 21 as the rotation axis of the rotating body, and the central axis 21 passes through a central point equidistant from each LED 3 in the light emitting group 4 and is perpendicular to the substrate 2 . In addition, the central axis 21 is the optical axis of the concave mirror 51 .

The reflector 5 reflects part of the light from the LEDs 31 and 32 on the inner surface of the concave reflector 51 in each light emitting group 4 , crosses the reflected light, and irradiates from the opening of the concave reflector 51 . Here, the LEDs 31 and 32 emit light at a wide angle from their light emitting center positions, and among the emitted lights along the substrate 2 substantially in parallel, light emitted from the light emitting center positions in opposite directions is reflected by the concave reflector 51 to intersect. At this time, the distance between the LEDs 31 and 32 is set according to the solid angle of the emitted light from the LEDs 31 and 32, the curvature of the reflection surface of the concave reflector 51, etc., so that the mixed light formed by each emitted light can be emitted more easily. . Thereby, color light from LED31 and 32 can be mixed easily.

(Modification)

FIG. 6 shows a modified example of the above-mentioned embodiment. In the light-emitting device 1 of this modification, each light-emitting group 4 (4a, 4b) has the lens 6 as an optical member which mixes the light of each LED31,32 in the said embodiment.

The lens 6 is arranged on the substrate 2 so as to cover the respective LEDs 31 and 32 in the respective light-emitting groups 4 , and has a lens main body 60 constituted by an inverted truncated cone-shaped rotating body. The lens main body 60 uses the center axis 21 perpendicular to the substrate 2 as a rotation axis in the same manner as above, and the center axis 21 is the optical axis of the lens 6 .

The lens main body 60 has an incident surface 61 formed on the bottom surface of the lens main body 60 and covering the two hemispherical cavities of the LEDs 31 and 32 respectively, a side surface 62 whose inclination angle becomes larger as it moves away from the substrate 2 and the central axis 21, and forms On the upper surface of the lens is a concave exit surface 63 and a convex exit surface 64 . The convex emission surface 64 is formed in a shape protruding from the center portion of the concave emission surface 63 .

In the lens 6, the light emitted from the LEDs 31 and 32 in the light-emitting group 4 enters the lens main body 60 from the incident surfaces 61 respectively, and the light near the central axis 21 in the incident light is away from the center on the convex exit surface 64. Axis 21 diffuses and emits. In addition, among the incident light from the incident surface 61 , the light away from the central axis 21 and toward the concave exit surface 63 is condensed toward the central axis 21 by the concave exit surface 63 and emitted, and the light from the incident surface 61 toward the side surface 62 is reflected by the side surface 62 And it is refracted on the concave emission surface 63 or the convex emission surface 64 to be emitted. As a result, the light incident from the incident surface 61 passes through the lens 6 and is diffused, condensed, multiple-reflected, etc., and intersects each other. Therefore, mixed light of light emitted from each LED 3 in each light emission group 4 can be easily obtained.

(third embodiment)

构成为使得从各组4中的LED3导出的光在扩散部件7上的投影图案71～73(投影部分)的周围彼此相邻(日文：隣接)或重叠。扩散部件7可以使用例如含有光扩散剂的透明树脂、玻璃材料等。A light emitting device according to a third embodiment of the present invention will be described with reference to FIG. 7 . As shown in FIG. 7( a ), the light-emitting device 1 of this embodiment further includes a diffusion member 7 that collectively diffuses the light emitted from each light-emitting group 4 in the above-mentioned embodiment. In the light-emitting device 1, the distance d1 between each light-emitting group 4 or the solid angle of the light derived from each group 4

The light emitted from the LED 3 in each group 4 is configured so that the surroundings of the projection patterns 71 to 73 (projection portions) on the diffusion member 7 are adjacent to each other (Japanese: adjacent) or overlapped. For the diffusion member 7, for example, a transparent resin containing a light diffusion agent, a glass material, or the like can be used.

各LED之间的距离d2及到扩散部件7的距离h求出各LED3的照射光在扩散部件7上的各投影图案，根据获得包含上述各投影图案的投影图案的照射角，等效地求出该立体角度

The light-emitting device 1 has a frame body 8 for supporting a plate-shaped diffusion member 7 on a substrate 2 , and the frame body 8 is configured to hold the diffusion member 7 at a distance h from the substrate 2 . Here, the solid angle of each light-emitting group 4 (4a-4c) It means the solid angle of the irradiation light which integrated (Japanese: integration) the light emitted from each said LED3 (31, 32) seen from the center of each group 4. For example, depending on the three-dimensional angle of the irradiated light of each LED

The distance d2 between each LED and the distance h to the diffusion member 7 are obtained for each projection pattern of the irradiated light of each LED3 on the diffusion member 7, and according to the irradiation angle of the projection pattern including the above-mentioned each projection pattern, equivalently obtain out of the solid angle

的点光源，各投影图案71～73由来自上述LED3的光投影而成为大致圆形状，其外径根据立体角度

和距离h来算出。此外，例如在立体角度

小时，通过将各发光组4之间的距离d1变窄，上述投影图案71～73能够彼此重叠。此外，在距离d1长时，可以增大立体角度

扩大投影图案来使各投影图案71～73彼此重叠。另外，LED3不限定于点光源。As shown in FIG. 7( b ), the diffusion member 7 projects the irradiation lights from the respective light emitting groups 4 a to 4 c on the plane thereof to form respective projection patterns 71 to 73 . Here, each LED 3 is set so that its irradiation light forms a solid angle

The point light source of each projection pattern 71-73 is projected by the light from the above-mentioned LED 3 and becomes a substantially circular shape, and its outer diameter depends on the solid angle

and distance h to calculate. Furthermore, for example in solid angle

When the distance d1 between the light emitting groups 4 is narrowed, the projected patterns 71 to 73 described above can overlap each other. In addition, when the distance d1 is long, the solid angle can be increased

The projected patterns are enlarged so that the respective projected patterns 71 to 73 overlap each other. In addition, LED3 is not limited to a point light source.

According to the present embodiment, the outgoing lights from the adjacent emission groups 4 intersect each other on the diffusion member 7 and are diffused in the diffusion member 7 to be emitted. Therefore, the color mixing range of the light is increased, and less chromaticity unevenness can be obtained. of mixed light.

In addition, this invention is not limited to the structure of the said embodiment, Various deformation|transformation is possible in the range which does not change the summary of invention. For example, in each of the above-mentioned embodiments, the case where there are two or three light-emitting groups 4 is shown, but there may be three or more groups. In addition, the LEDs included in the light-emitting group 4 may include solid-state light-emitting elements or phosphors that emit light in colors other than white, incandescent light, red, green, and blue. In addition, the arrangement shape of a plurality of LEDs on the substrate may be not only a linear shape or a rectangular shape, but also a polygonal shape or a circular shape. Such a light emitting device can be installed and used on various lighting fixtures.

In addition, the above-described Embodiments 1 to 3 may be combined. For example, the reflector and/or lens of Embodiment 2 may be applied to the light-emitting device of Embodiment 1, or the diffusion member of Embodiment 3 may be applied, or the reflection plate and lens of Embodiment 2 may be applied to the light emitting device. Mode 3 diffuser.

Preferred embodiments of the present invention have been described above, but the present invention is not limited to the specific embodiments described above, and various changes and corrections can be made within the scope of the claims, and it can be said that these also belong to the scope of the present invention.

Claims (9)

1. A light emitting device, characterized in that, A group is composed of a plurality of solid light-emitting elements that emit light of different chromaticities. The light-emitting device has a plurality of groups. Each group in the above-mentioned groups includes at least solid-state light-emitting elements that emit white light. The distance between the above-mentioned groups Set to be greater than the distance between solid light emitting elements within a group. 2. The lighting device according to claim 1, characterized in that, Each of the above-mentioned groups includes a solid-state light-emitting element that emits light in the color of an incandescent lamp. 3. The light emitting device according to claim 1, characterized in that, Each of the above-mentioned groups includes solid-state light-emitting elements that respectively emit light of at least two chromaticities of red, blue, and green. 4. The lighting device according to any one of claims 1 to 3, characterized in that, Each of the above-mentioned groups has an optical component that mixes colors of light from each solid state light emitting element. 5. The lighting device according to claim 4, characterized in that, The optical member is a reflective member that reflects light derived from the solid light emitting element. 6. The lighting device according to claim 4, characterized in that, The optical component is a lens that mixes colors of light emitted from the solid light emitting element. 7. The lighting device according to any one of claims 1 to 3, characterized in that, The distance between the light emitting centers of the nearest adjacent solid light emitting elements in the above group is within 15 mm, and the light beam of each of the above solid light emitting elements is 10 lumens to 600 lumens when 100% is lit. 8. The lighting device according to any one of claims 1 to 3, characterized in that, It also has a diffusion member that jointly diffuses the light emitted from the above-mentioned groups, and the distance between the above-mentioned groups or the solid angle of the light derived from the light-emitting group is configured so that the light derived from the above-mentioned solid light-emitting element passes through the above-mentioned diffusion member. Surroundings of the projected portions on are adjacent to or overlapping each other. 9. A lighting fixture characterized in that: The lighting device according to any one of claims 1 to 3 is provided.

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