JP4665205B2 - Linear light source for lamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear light source used in a lamp such as a vehicular lamp or various illumination lamps used as a headlamp or an auxiliary headlamp provided at the front of an automobile, for example.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, automobile headlamps are composed of a light source, a main reflecting surface made of, for example, a paraboloid that reflects light from the light source forward, and a diffusing lens cut. Light is converted into substantially parallel light by the main reflecting surface, and illumination light is irradiated forward.
As the light source, for example, a bulb such as a halogen bulb or a discharge lamp bulb is used.
Here, in such a bulb, the light emitting portion is formed in a linear or rectangular shape microscopically, but is treated as a point light source macroscopically.
[0003]
[Problems to be solved by the invention]
By the way, as a vehicular lamp using a linear light source, for example, a lamp using an LED array as a so-called high-mount stop lamp is known. However, such a high-mount stop lamp has a configuration in which the LED array is simply arranged at the rear portion of the automobile, and is not configured to control and use the light distribution pattern. For this reason, the light from the LED array which is a linear light source tends to diffuse slightly.
In addition to automotive headlamps, lamps that use linear light sources are actually used not only in automotive auxiliary headlamps, tail lamps, driving lamps, backup lamps, and other signal lights, but also in various lighting lamps. Absent.
[0004]
In view of the above, the present invention provides a linear light source having a light distribution pattern in which a boundary between an irradiation part and a non-irradiation part clearly appears in front of the light source on a screen arranged in front of the linear light source with a simple configuration. In particular, it is an object of the present invention to provide a linear light source that is optimal for a light source that is intended to partially limit the irradiation area, for example, a headlamp for passing light distribution in a vehicular lamp.
[0005]
According to the first configuration of the present invention, the object is arranged such that a linear light source arranged to extend in the lateral direction and light from the linear light source are reflected forward. A linear light source in a vehicle headlamp comprising a reflecting member, comprising: a linear light emitting portion configured linearly on a substrate; and a lens formed of a rotating surface disposed thereon. In addition, one side edge of the light emitting region extending in the longitudinal direction of the linear light emitting portion is disposed along the center of the lens and is disposed along the focal point of the reflecting member disposed above the substrate. This is achieved by a linear light source for a vehicle headlamp.
[0006]
Headlight for linear light source before for a vehicle according to the present invention, preferably, the linear light emitting portion is comprised of a plurality of light emitting elements arranged in a straight line.
[0007]
Headlight for linear light source before for a vehicle according to the present invention, preferably, the linear light emitting portion, an LED array.
[0008]
Headlight for linear light source before for a vehicle according to the present invention, preferably, the linear light emitting portion is a surface-emission element formed in a linear shape.
[0009]
Headlight for linear light source before for a vehicle according to the present invention, preferably, the light emitting surface side of the linear light emitting portion, and the wavelength converting material layer covering the linear light-emitting portion is formed, the wavelength converting material One side edge extending in the longitudinal direction of the layer is disposed at the center of the lens as one side edge of the light emitting region.
[0010]
In the linear light source for a lamp according to the present invention, preferably, the lens is formed in a semi-cylindrical shape.
[0011]
In the linear light source for a lamp according to the present invention, preferably, the lens is made of a resin material.
[0012]
In addition, according to the second configuration of the present invention, the object described above is such that a linear light source disposed so as to extend in the lateral direction and a line so as to reflect the light from the linear light source forward. A linear light source in a lamp comprising a reflective member disposed behind the linear light source, and a linear light-emitting portion composed of a plurality of light-emitting elements arranged linearly on the substrate; It is achieved by a linear light source for a lamp characterized by including a hemispherical lens arranged and centered on one side edge of each light emitting element.
[0013]
According to said 1st structure, it radiate | emitted from the linear light-emitting part, Preferably the linear light-emitting part which consists of several light emitting elements arrange | positioned linearly, for example, a LED array or the linearly formed surface light emitting element Light is emitted to the outside of the lens through a lens, preferably a lens made of a semi-cylindrical resin material.
[0014]
At that time, since the light emitted from one side edge of the light emitting region of the linear light emitting unit is emitted radially outward from the center of the lens, the lens goes straight without being refracted by the lens. It will be emitted to the outside.
Therefore, when reflected by the reflecting member and irradiated forward, the contrast of the boundary between the irradiation region and the non-irradiation region of the light distribution pattern formed by the boundary line of the light emitting region of the linear light emitting part is good. It becomes.
[0015]
A wavelength converting material layer is formed on the light emitting surface side of the linear light emitting portion so as to cover the linear light emitting portion, and one side edge extending in the longitudinal direction of the wavelength converting material layer is one side edge of the light emitting region. As described above, when the lens is disposed at the center of the lens, the wavelength conversion material layer is excited by the light emitted from the linear light emitting portion, and light having a different wavelength is emitted from the wavelength conversion material layer. The light emitted from the wavelength conversion material layer is emitted outside the lens in the same manner.
[0016]
At that time, the light emitted from one side edge of the wavelength conversion material layer as the light emitting region is emitted radially outward from the center of the lens, and thus travels straight without being refracted by the lens. The light is emitted to the outside of the lens.
Therefore, when the light is reflected by the reflecting member and irradiated forward, the contrast of the boundary between the irradiation region and the non-irradiation region of the light distribution pattern formed by the boundary line of the wavelength conversion material layer becomes good.
[0017]
Moreover, according to said 2nd structure, the light radiate | emitted from each light emitting element of a linear light emission part is radiate | emitted on the outer side of a lens via a corresponding semispherical lens, respectively.
At that time, since the light emitted from one side edge of each light emitting element is emitted radially outward from the center of the corresponding lens, the light goes straight without being refracted by the lens. The light is emitted to the outside.
Accordingly, when the light is reflected by the reflecting member and irradiated forward, the contrast of the boundary between the irradiation region and the non-irradiation region of the light distribution pattern formed by the boundary line of each light emitting element of the linear light emitting unit is It becomes good.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 10.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. As long as there is no description of the effect, it is not restricted to these aspects.
[0019]
FIG. 1 shows a configuration in which a first embodiment of a linear light source for a lamp according to the present invention is applied to a vehicular lamp.
In FIG. 1, a vehicular lamp 10 forms a horizontal diffused light distribution of a so-called low beam automobile headlamp, and is disposed on a linear light source 11 and a rear side of the linear light source 11. And the reflecting member 20.
[0020]
As shown in the drawing, the linear light source 11 is composed of a base 12 provided with a linear light-emitting portion and a lens 13.
The base 12 is configured by installing a linear light-emitting portion composed of the LED array module 14 in a recess 15 a provided in the substrate 15 along the longitudinal direction.
Here, as shown in FIG. 2, the LED array module 14 includes a plurality of, for example, 5 to 10 (5 in the illustrated example) LEDs mounted side by side in the recess 15a of the substrate 15 in the longitudinal direction. It is comprised from the chip | tip 16 and the fluorescent substance layer 17 as a wavelength conversion material layer arrange | positioned so that LED chip 16 may be covered.
[0021]
The LED chip 16 is configured as, for example, a blue LED having a chip size of one side length D (= 1.0 mm), and each LED chip 16 is brought into contact with the wall surface 15b of the recess 15a. By being displaced laterally from the center in the longitudinal direction of the substrate 15 by a distance D / 2, for example, with a distance d (= 1.3 mm), the one side edge 16a in the longitudinal direction is arranged in the longitudinal direction of the substrate 15. Arranged along the center.
[0022]
The phosphor layer 17 is made of, for example, a YAG phosphor, and is excited by the irradiation light from the LED chip 16 to emit white light.
Further, the phosphor layer 17 is formed in the recess 15 a so that one side edge 17 a thereof coincides with the one side edge 16 a of the LED chip 16.
[0023]
In addition, a transparent intermediate member 18 is formed on the LED array module 14 so as to cover almost the entire surface of the substrate 15, thereby preventing a gap between the LED array module 14 and the lens 13, The light extraction efficiency is not lowered.
The intermediate member 18 is preferably made of a material having a refractive index close to the refractive index of the lens 13 or a material having an intermediate refractive index between the lens 13 and the LED chip 16 in terms of light extraction efficiency. For example, the intermediate member 18 is flexible such as silicon gel or liquid polymer. Materials are used.
[0024]
Further, the lens 13 is made of, for example, a transparent resin material so as to cover the entire surface of the substrate 15 of each LED array module 14 of the base 12.
The lens 13 has a semi-cylindrical outer shape extending in the longitudinal direction, and the center axis thereof is formed so as to substantially coincide with the one side edge 16a of each LED chip 16.
Here, when the semi-cylindrical radius of the lens 13 is R, the length of one side of the LED chip 16 is D, and the critical angle is α, the following formula R ≧ √2 · D / sin α
Accordingly, by determining the radius R, the total reflection on the inner surface of the lens 13 can be reduced with respect to the light emitted from the LED chip 16. For example, when the radius R is set to 2.1 mm, if D = 1.0 mm and α = 42.5 degrees, the effective light can be extracted with an extraction efficiency of about 80.0%.
[0025]
In this way, the light emitting part composed of the LED chip 16 is shifted and arranged so that one side edge is located at the position coincident with the central axis of the lens 13 instead of the center of the light emitting part. As shown in FIG. 3, the directivity of the linear light source 11 emits light, and the directivity of the linear light source 11 is inclined in the direction opposite to the side where the LED chip 16 is shifted (leftward in FIG. 3). Become. In FIG. 3, the normal direction is 0 degree, the left side is the minus direction, and the right side is the plus direction.
And the 1st reflective surface 21 mentioned later is arrange | positioned in an irradiation direction, ie, the drawing left side, so that the light of the central axis of this inclined directivity characteristic may be reflected. Here, in order to increase the utilization efficiency of the light emitted from the linear light source 11 and to reduce the size of the entire lamp 10 using the linear light source 11, the central axis is practically in the range of 20 to 50 degrees. It is desirable to incline at.
[0026]
The reflection member 20 reflects, for example, light from the linear light source 11 and reflects the light forward, and the first reflection surface 21 concave toward the front and both sides of the first reflection surface 21. And a second reflecting surface 22 provided on the surface.
[0027]
The first reflective surface 21 is formed as an elliptical reflective surface in a cross section perpendicular to the longitudinal direction of the linear light source 11.
Here, the elliptical reflective surface includes an elliptical surface and a reflective surface that can be approximated to an elliptical surface. In the following explanation, the explanation will be based on the ellipsoidal surface for easy understanding, but the cross-sectional shape uses a rational Bezier curve (= conical curve) and NURBS (written by Toshiya Hiroshi; 3D CAD) It may be a curve obtained by approximating a conic curve by a free curve such as (Basic and Application; issued by Kyoritsu Publishing Co., Ltd.).
The first reflecting surface 21 is formed on the lens 13 side so as to be within a range of 0 to 120 degrees when the surface of the base 12 of the linear light source 11 is 0 degrees.
In FIG. 1, the first reflecting surface 21 is formed in a so-called kamaboko shape so as to have the same shape at any cross-sectional position, but is not limited thereto, and is formed so as to have a curvature in the longitudinal direction. May be.
[0028]
Then, as shown in FIG. 4, the first reflecting surface 21 is positioned so that the first focal position 21a is located near the center of the lens 13 of the linear light source 11 arranged upward. The focal position 21b is arranged so as to be located about 0.5 degrees below the first focal position 21a, for example, about 25 m ahead of the screen, so as to satisfy the regulations as a headlamp. .
Here, as shown in FIG. 4, the linear light source 11 has one side edge 16a of the LED chip 16 coinciding with the first focal position 21a of the first reflecting surface 21, and the LED module 14 as a whole. Are arranged in front of the first focal position 21a.
[0029]
Thereby, the one side edge 16a of each LED chip 16 of the linear light source 11 and the one side edge 17a of the phosphor layer 17 are along the center of the lens 13 and the first focal position 21a of the first reflecting surface 21. Since each LED chip 16 and the entire phosphor layer 17 are disposed in the vicinity from the first focal position 21a, one side edge 16a and each phosphor layer 17 of each LED chip 16 are located in the vicinity. The light L1 emitted from one side edge of the lens 13 is reflected by the first reflecting surface 21 without being refracted in the cross section perpendicular to the longitudinal direction of the lens 13, and proceeds toward the second focal position 21b. In this example, it proceeds slightly downward from the horizontal.
[0030]
In addition, since each LED chip 16 is arranged so as to be positioned in front of one side edge 16a, the light L2 emitted from the other side edge of each LED chip 16 is refracted by the lens 13. The light is reflected by the first reflecting surface 21 and travels downward from the light L1.
Accordingly, the light emitted from the LED chip 16 and the phosphor layer 17 and reflected by the first reflecting surface 21 is irradiated forward and below the second focal position 21b below the horizontal line. At the same time, the light L1 emitted from the one side edge 16a of the LED chip 16 and the one side edge of the phosphor layer 17 is not refracted in a cross section perpendicular to the longitudinal direction of the lens 13, so that the first reflection The contrast of the boundary between the irradiated region and the non-irradiated region in the horizontal direction of the light reflected by the surface 21 and irradiated forward and below the horizontal line becomes good.
[0031]
On the other hand, as shown in FIG. 5, the second reflecting surface 22 of the reflecting member 20 is formed as a composite parabolic reflecting surface that becomes a plurality of parabolas in a cross section perpendicular to the longitudinal direction and the optical axis direction. ing.
Here, the parabolic reflecting surface includes a parabolic surface and a reflecting surface that can be approximated to a parabolic surface.
For example, the parabolic reflecting surface is emitted from the opposite edge 11a of the linear light source 11 on both sides of the first reflecting surface 21 (only one side is shown in FIG. 5). The target point A is focused to reflect the light having the maximum diffusion angle θ (for example, 45 degrees) reflected by the reflecting surface 21 and irradiate the light toward the target point A for obtaining a predetermined light distribution on the screen. And an axis B inclined by an angle θ with respect to the center axis from the target point A, and a parabola C starting from an end 21a on one side of the first reflecting surface 21.
[0032]
The end point 22 a of the parabolic reflection surface is a position where light having the maximum diffusion angle θ that is emitted from the opposite edge of the linear light source 11 and reflected by the first reflection surface 21 is incident.
By setting such a target point A for each surface of the compound parabolic reflection surface, a predetermined light distribution can be obtained.
[0033]
The vehicular lamp 10 according to the embodiment of the present invention is configured as described above, and each LED chip 16 of the linear light source 11 is supplied with power by a drive circuit (not shown) to emit light, whereby each LED of the linear light source 11 is emitted. The light emitted from the chip 16 is irradiated toward the front by being reflected by the first reflecting surface 21 and the second reflecting surface 22 of the reflecting member 20.
[0034]
Here, when the light emitted from the linear light source 11 is reflected by the first reflecting surface 21 of the reflecting member as shown in FIG. 6, the vertical direction is based on the shape of the first reflecting surface 21. By being controlled, it is irradiated slightly downward from the horizontal line H, and when reflected by the second reflecting surface 22, based on the target point of each composite reflecting surface of the second reflecting surface 22. By being controlled in the horizontal direction, it is limited to the maximum diffusion angle θ. As a result, a light distribution pattern suitable for downward light distribution in a so-called passing beam as shown in FIG. 7 is obtained.
[0035]
In addition, with respect to the linear light source 11 for lamps, one side edge of each LED chip 16 of the base 12 as the linear light emitting portion is located along the center of the lens 13. As a result, the light emitted from the one side edge 16a of each LED chip 16 that is the light emitting region of the base 12 is emitted radially outward from the center of the lens 13, so that the refractive action by the lens 13 is reduced. Without being received, the light travels straight and exits outside the lens 13 and enters the reflection member 20.
Therefore, the light distribution pattern reflected by the reflecting member 20 and irradiated forward is formed by one side edge 16a as a boundary line of each LED chip 16 which is a light emitting region of the base 12 which is a linear light emitting part. The contrast of the boundary between the irradiated area and the non-irradiated area of the light distribution pattern is improved. Accordingly, it is possible to obtain a cut-off for a low beam without using a shutter member for cut-off like a lamp using a conventional bulb.
[0036]
In the vehicle lamp 10 described above, in the linear light source 11, the LED chip 16 is disposed on the upper surface of the substrate 15 on the optical axis O, that is, upward, and the reflecting member 20 is disposed on the upper side of the optical axis O. However, the present invention is not limited to this, and as shown in FIG. 8, the linear light source 11 is disposed downward on the optical axis O, and the reflecting member 20 is disposed below the optical axis O. Also good.
In this case, in the linear light source 11, the one side edge 16a of the LED chip 16 and the one side edge 17a of the phosphor layer 17 are coincident with the first focal position 21a of the first reflecting surface 21, and the whole is formed. It arrange | positions so that it may be located behind the 1st focus position 21a.
As a result, similarly to the arrangement shown in FIG. 4, the light emitted from the linear light source 11 is reflected by the first reflecting surface 21 of the reflecting member 20, so that it is slightly below the optical axis O. It will be irradiated towards.
[0037]
FIG. 9 shows the configuration of the second embodiment of the linear light source for lamps according to the present invention.
In FIG. 9, the linear light source 30 for lamps is comprised from the LED array 31 as a linear light emission part, and the lens 32. As shown in FIG.
The LED array 31 is composed of a plurality of LED chips 34 mounted side by side on the substrate 33 in the longitudinal direction.
In this case, the phosphor layer and the intermediate member are not shown, but are actually provided in the same manner as the base 12 in the linear light source 11 shown in FIG.
[0038]
The LED chip 34 is configured, for example, as a blue LED having a chip size of one side length D (= 1.0 mm), and each LED chip 34 is laterally spaced from the center in the longitudinal direction of the substrate 33 by a distance D / 2. For example, the one side edge 34 a in the longitudinal direction is disposed along the center in the longitudinal direction of the substrate 33 by being disposed at a distance d (= 3.6 mm).
[0039]
The lens 32 is formed so as to cover each LED chip 34 of the LED array 31.
The lens 32 has a semi-spherical outer shape, and its center is formed so as to substantially coincide with the one side edge 34a of each LED chip 34.
Here, when the semispherical radius of the lens 32 is R, the length of one side of the LED chip 34 is D, and the critical angle is α, the following equation R ≧ √5 · D / 2sin α
Accordingly, by determining the radius R, the total reflection on the inner surface of the lens 32 can be reduced with respect to the light emitted from the LED chip 34. For example, when D = 1.0 mm, α = 42.5 degrees, and radius R = 2.1 mm, the effective light can be extracted with an extraction efficiency of about 97.8%.
[0040]
According to the linear light source 30 for a lamp having such a configuration, the light emitted from the linear light source 30 is the same as that of the linear light source 11 for the lamp described above. A light distribution pattern slightly below the horizontal line H similar to that shown in FIG. 7 is formed by being reflected by the second reflecting surface 22 and being irradiated forward.
[0041]
FIG. 10 shows a third embodiment of a linear light source for a lamp according to the present invention.
In FIG. 10, the lamp linear light source 40 has substantially the same configuration as that of the lamp linear light source 30 shown in FIG.
The lamp linear light source 40 is formed in a shape in which the distance between the LED chips 34 is as short as d (= 2.4 mm), for example, and the lens 32 overlaps with the lamp linear light source 30 of FIG. It has a different structure only in that it is.
[0042]
According to the linear light source 40 for a lamp having such a configuration, the same effect as that of the linear light source 30 for a lamp shown in FIG. 9 can be obtained, and the LED chips 34 are arranged more densely. A light source is obtained.
In this case, when the radius R of the lens 32 is 2.1 mm, the effective light can be extracted with an extraction efficiency of about 92.6 mm.
[0043]
In the above-described embodiments, the linear light sources 11 and 30 for the lamps used for the vehicle lamp 10 as the horizontal diffused light distribution in the headlight for the passing beam of the automobile have been described. However, the light distribution according to these embodiments is described. A lamp with a light distribution suitable for the standard of a low beam headlamp can be obtained by further superimposing a light distribution light that irradiates a region 15 degrees diagonally upward to the right or left on the pattern.
[0044]
Furthermore, in the above-described embodiment, a base as an LED array in which a plurality of LED chips are arranged side by side is used, but a surface light emitting element such as an EL (electroluminescence element) formed extending in the longitudinal direction is used as a light source. May be used.
Moreover, although the linear light sources 11 and 30 for lamps used in the vehicular lamp 10 as a headlamp for a passing beam of an automobile have been described, the present invention is not limited thereto, and the present invention is not limited to a headlight for a traveling beam of an automobile. Lights, or auxiliary lights for automobiles (fog lamps, driving lamps, backup lamps, etc.), signal lights for automobiles (tail lamps, turn lamps, stop lamps, etc.) It is apparent that the present invention can be applied to a linear light source for a lamp for use in various lamps such as a lamp, a general indicator lamp, and a general signal lamp.
[0045]
【The invention's effect】
As described above, according to the present invention, a linear light emitting portion, preferably a linear light emitting portion comprising a plurality of light emitting elements arranged in a straight line, for example, an LED array or a linearly formed surface light emitting element. Since the light emitted from one side edge of the light emitting region is emitted radially outward from the center of the lens, it goes straight out without being refracted in the lens cross section. become.
Therefore, when reflected by the reflecting member and irradiated forward, the contrast of the boundary between the irradiation region and the non-irradiation region of the light distribution pattern formed by the boundary line of the light emitting region of the linear light emitting part is good. It becomes.
[0046]
In this way, according to the present invention, a linear configuration suitable for a lamp, in particular, a vehicular lamp, which can realize a good contrast at the boundary between an irradiation area and a non-irradiation area of a light distribution pattern with a simple configuration. A light source may be provided.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing a vehicular lamp incorporating a first embodiment of a linear light source for a lamp according to the present invention.
2A is a perspective view, FIG. 2B is a plan view, and FIG. 2C is a side view illustrating a configuration of a linear light source in the vehicular lamp of FIG. 1;
3 is a graph showing directivity characteristics of a linear light source in the vehicular lamp of FIG. 1. FIG.
4 is a schematic side view showing the vehicular lamp in FIG. 1. FIG.
FIG. 5 is a schematic plan view showing the vehicular lamp in FIG. 1;
6 is a schematic perspective view showing the operation of the vehicular lamp in FIG. 1. FIG.
7 is a schematic view showing a light distribution pattern by the vehicular lamp of FIG. 1. FIG.
8 is a schematic side view showing a modified example of the vehicular lamp in FIG. 1. FIG.
9A is a schematic perspective view, FIG. 9B is a sectional view, and FIG. 9C is a partial plan view showing a second embodiment of a linear light source for a lamp according to the present invention.
10A is a schematic perspective view, FIG. 10B is a sectional view, and FIG. 10C is a partial plan view showing a third embodiment of a linear light source for a lamp according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Vehicle lamp 11 Linear light source 12 Base 13 Lens 14 LED array module 15 Board | substrate 16 LED chip 16a One side edge 17 Phosphor layer (wavelength conversion material layer)
17a One side edge 18 Silicon gel 20 Reflective member 21 First reflective surface 22 Second reflective surface 30, 40 Linear light source 31 for lamps LED array 32 Lens 33 Substrate 34 LED array 34a One side edge

Claims (5)

A linear light source in a vehicular headlamp, comprising: a linear light source disposed so as to extend in a lateral direction; and a reflective member disposed so as to reflect light from the linear light source forward. Because
A linear light-emitting portion configured linearly on the substrate, and a lens formed of a rotating surface disposed thereon ,
One side edge of the light emitting region extending in the longitudinal direction of the linear light emitting portion is disposed along the center of the lens and is disposed along the focal point of the reflecting member disposed above the substrate . A linear light source for a vehicle headlamp characterized by the above.   The linear light source for a vehicle headlamp according to claim 1, wherein the linear light-emitting portion includes a plurality of light-emitting elements arranged linearly.   The linear light source for a vehicle headlamp according to claim 2, wherein the linear light emitting unit is an LED array.   The linear light source for a vehicle headlamp according to claim 1, wherein the linear light emitting section is a surface light emitting element formed in a linear shape. A wavelength conversion material layer is formed on the light emitting surface side of the linear light emitting part so as to cover the linear light emitting part,
5. The vehicle according to claim 1, wherein one side edge extending in a longitudinal direction of the wavelength conversion material layer is disposed at the center of the lens as one side edge of the light emitting region. Linear light source for headlamps.

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