DE102019211799B4 - Device for generating a light distribution for a vehicle - Google Patents

Abstract

Device for generating a light distribution for a vehicle; comprising a light source (1) for generating light emission; anda light guide element (10) with a coupling-in section (4) and an out-coupling section (5); wherein the light emission can be coupled into the coupling section (4); wherein the outcoupling section (5) has a longitudinal extent and is designed to guide the coupled-in light emission along its longitudinal extent; wherein the coupling-out section (5) has coupling-out elements (7, 8) which are designed to couple out the coupled-in light emission perpendicular to the longitudinal extent of the coupling-out section (5); wherein in a transition region from the coupling-in section (4) to the coupling-out section (5) of the light guide element (10), a deflection element (9) is arranged such that a first and a second part of the coupled-in light emission is directed in different directions along the longitudinal extent of the coupling-out section (5). are guided, characterized in that a scattering element (11) is formed in the area of the deflection element (9) in an extension of the coupling section (4), the scattering element (11) having a roller-, spherical or ellipsoid-shaped surface with a reflective coating.

Description

The present invention relates to a device for generating a light distribution for a vehicle. The device comprises a light source for generating light emission and a light guide element with a coupling section and a coupling out section. The light emission can be coupled into the coupling-in section, the coupling-out section having a longitudinal extent and being designed to guide the coupled-in light emission along its longitudinal extent. The coupling-out section has coupling-out elements which are designed to couple out the coupled-in light emission perpendicular to the longitudinal extent of the coupling-out section.

Modern lighting devices, for example for illuminating a vehicle interior or for emitting light signals from a vehicle, can be designed very discreetly due to the ongoing development of increasingly efficient and smaller light sources. They therefore allow great design freedom that was hardly possible with classic lights.

In the US 6,450,662 B1 A lighting device is described in which an array of light-emitting diodes emits light, which is then directed to a diffuser using light guides. Alternatively, lenses can be used that ensure homogeneous illumination of a diffuser surface.

From the US 7,001,054 B2 A vehicle light is known in which light from a light-emitting diode is guided through a light guide into a mushroom-shaped screen area. There, part of the light is coupled out to the front and the other part is directed in a backward direction onto a reflector.

In the US 2011/0261570 A1 A lighting unit is disclosed that includes a light source with an optical axis and a light guide body. The light guide body includes a light incident portion at a front of the light source protruding from a first surface, a light exit portion shaped to extend in a first direction on a second surface, and a light guide portion.

In the US 2005/0265041 A1 An optical body is described which receives the light emitted by a light source in a conical spatial region with a central axis running in the Z direction. The optical body is essentially V-shaped in a sectional plane defined by the Z direction and an X direction perpendicular thereto.

The US 2006/0164839 A1 describes a light guide assembly that includes a base and a light source removably attached to the base. The light source is oriented to emit light outward and away from the base.

The US 2006/0171159 A1 describes a rear light, in particular a brake light for a motor vehicle, which includes at least one primary light source, which consists of at least one light-emitting diode that is connected to a light guide.

The US 6,097,549 A discloses a bi-reflective lens element that has a light entry surface and a direct transmission area connected to the light entry surface. A light source is arranged adjacent the light entrance surface to project light into the lens element and create a light emitting arrangement.

The US 2008/0049445 A1 describes various embodiments of corner-coupled backlights in which one or more LEDs are optically coupled to a cut corner of a solid rectangular light guide. In one embodiment, a high power white light LED is mounted in a small reflective cavity that is then coupled to a flattened corner of the light guide.

The present invention is based on the object of providing a device for generating a light distribution which can be implemented with a particularly simple structure and requires as little space as possible.

According to the invention, this object is achieved by a device having the features of claim 1. Advantageous refinements and further developments result from the dependent claims.

In the device according to the invention, a deflection element is arranged in a transition region from the coupling-in section to the coupling-out section of the light guide element in such a way that a first and a second part of the coupled-in light emission are guided in different directions along the longitudinal extent of the coupling-out section.

In the case of the invention, the device can therefore advantageously be designed to be particularly space-saving. The redirection of the coupled light enables a particularly flat design. The light emission provided by the light source can also be used particularly efficiently.

The light source is formed in a manner known per se. In particular, it includes an LED, but can in principle be designed in any way. The light emission is in particular formed in one color, and the light source can be controlled in such a way that the light emission can be generated with different intensities and/or colors. The light emission can also be generated in a time-varying manner, for example with a dynamic change in the light intensity, for example with a flashing light or with a light intensity adapted to an ambient brightness, for example a higher intensity with a higher ambient brightness.

The light emission is at least partially coupled into the light guide element, whereby the light emission can be influenced in a manner known per se, in particular by means of optical elements such as reflectors or lenses. The coupling itself also takes place in a manner known per se.

The light emission is coupled into the coupling section of the light guide element in such a way that the coupled light is guided in the light guide element in a manner known per se, in particular by being reflected to a surrounding medium such as air when it hits an interface of the light guide element. This is done in particular by total reflection, which means that coupled light hits an interface with an optically thinner medium at an angle that meets the conditions for total reflection. To decouple the light, the angle of the direction of propagation of the light relative to the surface is changed so that the conditions for total reflection are no longer met and at least part of the light emerges from the light guide element.

The direction of propagation of the light in the light guide element therefore changes with every reflection on the surface. For the purposes of the invention, however, it is assumed that the direction of light propagation is defined along a longitudinal axis of the light guide element or of the first or second section. This means that even if the actual direction of a light beam changes again and again due to reflection during its conduction in the light guide element, the direction of propagation is still determined by the geometry of the light guide element.

In particular, the coupling-in section has a further longitudinal extent which runs obliquely to the longitudinal extent of the coupling-out section, that is, the longitudinal extents of the coupling-in and decoupling sections are not parallel to one another. That is, the light emission coupled into the coupling-in section is directed in a direction which is oblique to the propagation direction of the light in the coupling-out section. In particular, the light in the coupling-in section propagates obliquely or perpendicularly to the longitudinal extent of the coupling-out section. In particular, the propagation of the coupled-in light emission in the coupling-in section also runs obliquely, in particular perpendicularly, to the longitudinal direction of the coupling-out section.

After hitting the deflection element, the first part of the light emission is directed in a first direction and the second part of the light emission is directed in a second direction, in particular in opposite directions along the longitudinal extent.

In the device, the coupled-in light is guided along the longitudinal extent of the coupling-in section or the longitudinal extent of the coupling-out section. In particular, two opposite directions are defined along a longitudinal extent. The device for generating a light distribution can, for example, be arranged in a vehicle such that the propagation directions coincide with axes in a vehicle coordinate system. For example, the longitudinal extent of the coupling section can run parallel to a z-axis of the vehicle, that is, a vertical axis. Furthermore, the longitudinal extent of the decoupling section can run parallel to a y-axis of the vehicle, that is to say a horizontal transverse axis of the vehicle. In such a case, a horizontal longitudinal axis of the vehicle would be defined as the x-axis.

The longitudinal dimensions run obliquely to one another, that is, they do not run parallel to one another. They can be perpendicular to each other or arranged at a different angle to each other.

In the device, in particular the first part of the coupled-in light emissions is directed in a first direction and the second part in a second direction along the longitudinal extent of the coupling-out section. The first direction is in particular opposite to the second direction, so that the first and second parts are guided away from one another along the longitudinal extent or in directions directed towards one another. The longitudinal extension can also be defined so that it has an angle, such as a course with a bend, so that the first and second directions differ from each other by this angle.

In one embodiment of the device according to the invention, the coupling-in section and the coupling-out section of the light guide element are formed in one piece. In particular, the entire light guide element is designed in one piece. This advantageously avoids transitions between different optical media and the device can be installed particularly easily.

The deflection element can also be formed in one piece with the light guide element. In further embodiments, the light guide element can be designed in several pieces, with the first and second sections, for example, being designed as separate parts and being connected to one another in an optically transparent manner.

In one embodiment, the deflection element is designed as a recess with flat surfaces formed in the light guide element. The device is therefore advantageously constructed in a particularly simple manner and the light distribution can easily be distributed into the second section.

In particular, a region of the light guide element is designed as a deflection element. For example, the light guide element in the deflection element has a recess such that flat surfaces or surfaces of a different geometry are formed at an interface to the surrounding optically thinner medium, in particular air. In particular, total reflection occurs on these surfaces, so that coupled light striking at a suitable angle does not pass through the surfaces into the optically thinner medium, but is reflected. The deflection element is arranged in such a way that the reflected light in the coupling-out section of the light guide element is guided in different directions, or in a first and second direction along the longitudinal extent of the coupling-out section. The deflection element is in particular designed with at least two surfaces arranged at a certain angle to one another and thus allows the incident light to be deflected in two different directions, that is to say the first and the second direction along the decoupling section.

The flat surfaces, or possibly differently shaped surfaces, of the deflection element can, for example, be arranged at a right angle to one another, with the reflected light being able to be directed in opposite directions. The surfaces may also be at a different angle to one another such that the first and second parts are deflected in different directions that are not exactly opposite to one another.

The deflection element can also be designed in such a way that instead of flat surfaces, bends are provided, which in particular have a small radius, which is designed in such a way that light is guided in this area by total reflection.

In further exemplary embodiments, the deflection element can be designed in a different way. It can, for example, include an arrangement of reflecting or mirroring surfaces. It can also be designed as a separate component.

According to the invention, a scattering element is formed in the area of the deflection element in an extension of the coupling section. As a result, an area of increased light intensity can advantageously be avoided and a homogeneous light distribution is achieved. In particular, the scattering element is formed in an extension of the direction of propagation of the light emission coupled and guided in the coupling section.

This in particular prevents a portion of the light emission that is emitted in an extension of the coupling section and is not deflected by the deflection element in the first or second direction from emerging from the light guide element. This can occur, for example, if the coupling in of the light emission is not completely successful or if scattering effects lead to the undesired coupling out of light from the coupling section or in the deflection element.

The scattering element is designed in particular in such a way that incident scattered light is deflected as evenly as possible in different directions or along the longitudinal extent of the decoupling section in the first and second directions. According to the present invention, this is achieved by a roller, spherical or ellipsoidal surface with a reflective coating.

In a further development, the scattering element is formed in a housing, the housing being designed to accommodate the light guide element. The scattering element is therefore advantageously designed to be particularly simple.

The housing can be designed in a manner known per se and serve to hold the light guide element and, if necessary, other elements of the device. Furthermore, optical shielding can be carried out in order to prevent unwanted light from escaping and to shape the light distribution generated, for example by means of a veneer. Surfaces of the housing that are too directed towards the light guide element, be coated white or reflective in some other way to avoid light loss.

A scattering element formed in the housing can be designed, for example, as a convex region or as a thickening in an area in which the deflection element of the light guide element is arranged. It can also have a spherical or roller-shaped surface. For example, the housing can be formed by injection molding, with the scattering element already provided in the shape of the housing.

In one embodiment, a collimator is arranged between the light source and the coupling section of the light guide element in such a way that the coupled light emission in the coupling section of the light guide element runs parallel to a longitudinal extent of the coupling section. The light emission can thereby advantageously spread in such a way that it can be controlled particularly easily in the first section of the device.

A parallel light beam can therefore first be generated based on the light emission and guided in the coupling section of the light guide element. In particular, the light is bundled during coupling, for example by designing a coupling surface in such a way that light emission from a substantially point-shaped light source is formed at a certain distance from a parallel light bundle.

In particular, the parallel light bundle runs parallel to the longitudinal axis of the coupling section of the light guide element. The light is then directed essentially without total reflection and the light hits the deflection element directly. Alternatively or additionally, a coupled light emission can be guided in the coupling section by means of total reflection. The light emission can be changed before coupling by means of a lens, for example in order to achieve bundling, whereby a light bundle can in particular have a parallel course, a fanned-out course or a course that is focused on a focal point. The light emission can also be coupled onto a flat or curved surface.

In a further embodiment, the device has a shielding element surrounding the coupling section. This can advantageously prevent light from emerging from the first section, for example due to scattering. This also makes it possible to avoid a higher intensity of light being coupled out at the position of the deflection element due to scattered light.

The shielding element can be designed, for example, as a collar that at least partially surrounds the coupling section. It is in particular formed from an opaque material, with the light being reflected or absorbed in particular by the shielding element.

In a further development, the coupling-out elements are essentially arranged in a plane spanned by the coupling-in section and the coupling-out section. As a result, the light distribution is advantageously coupled out perpendicular to the plane of the device.

The outcoupling elements are designed, for example, at an interface between the light guide element and an optically thinner medium so that coupled light is reflected in their area so that it is coupled out into the surrounding optically thinner medium at a further interface. The output elements can, for example, have a prism or notch structure.

When the coupling-out elements are arranged in a common plane, in particular in the plane which is spanned by the longitudinal extents of the coupling-in section and the coupling-out section or which runs parallel thereto, the light is coupled out in particular along a third direction which runs perpendicular to this plane. This allows a particularly flat design to be achieved, for example by reducing the depth of the required installation space in the third direction. The light is guided along the longitudinal extents of the coupling and decoupling section in order to then couple it out along the third direction.

In further developments, the decoupling elements can be arranged in a different way, in particular in different levels. The light extraction can therefore take place in different directions.

In one embodiment, the decoupling elements are set up to decouple the light distribution into an exterior space of the vehicle. The device can advantageously be used to output a light signal. Alternatively, the interior of the vehicle can also be illuminated.

For example, the outcoupling section of the light guide element is designed so that it runs along a line of light, and the outcoupling elements are designed so that through light directed through the outcoupling section of the light guide element in the different directions is coupled out to form the light line. Alternatively or in addition to a line, other structures and light distributions can be formed.

The device can, for example, be arranged in a rear area of a vehicle in such a way that a line of light visible to following vehicles is generated for a tail light, a brake light or a rear fog light.

In a further embodiment, the light distribution can be coupled out through a diffuser. As a result, the structures for coupling out the light distribution can advantageously be hidden.

The diffuser can be designed in a manner known per se and, for example, have a structured surface or a volume-scattering material on which incident light is scattered or refracted in different directions in order to conceal structures behind it.

In a further development, the device comprises at least one further coupling section, through which light emission from a second light source can be coupled, and a further deflection element, which is arranged in a transition region from the further coupling section to the coupling out section of the light guide element in such a way that a first and a second part the coupled light emission of the second light source can be directed in different directions along the longitudinal extent of the outcoupling section.

For example, several coupling sections, through which the light emissions from several light sources can be coupled into the light guide element, are arranged so that the coupled light reaches a common second section. In particular, the plurality of coupling-in sections each have a longitudinal extension which spans a common plane in which the coupling-out section is also arranged. Furthermore, a control can be provided in such a way that a running light can be generated, in which light sources are activated one after the other, the light emissions of which are coupled into coupling sections arranged next to one another. Furthermore, the light emissions can be controlled separately or in a coordinated manner.

The further coupling sections can be constructed analogously to the coupling section according to the previous description. Likewise, the further deflection elements can be formed analogously to the deflection element described above, for example as a recess in the light guide element. This means that in this case, in particular, a plurality of coupling-in sections are arranged on the coupling-out section and, in particular, are formed in one piece with it. The coupling-in sections can, for example, be arranged equidistant from one another along the longitudinal extent of the coupling-out element.

In particular, the coupling-in sections are arranged in a common plane with the coupling-out section.

A vehicle according to the invention comprises at least one device according to the present description.

• 1 und 2 zeigen ein erstes Ausführungsbeispiel der erfindungsgemäßen Vorrichtung,
• 3 und 4 zeigen ein zweites Ausführungsbeispiel der erfindungsgemäßen Vorrichtung ohne und mit einem Abschirmungselement,
• 5 zeigt ein drittes Ausführungsbeispiel der erfindungsgemäßen Vorrichtung in einem Gehäuse und
• 6 zeigt ein viertes Ausführungsbeispiel der erfindungsgemäßen Vorrichtung.

The invention will now be explained using exemplary embodiments with reference to the drawings.

• 1 and 2 show a first exemplary embodiment of the device according to the invention,
• 3 and 4 show a second embodiment of the device according to the invention without and with a shielding element,
• 5 shows a third embodiment of the device according to the invention in a housing and
• 6 shows a fourth embodiment of the device according to the invention.

With reference to the 1 and 2 A first exemplary embodiment of the device according to the invention is explained. 1 shows a frontal view of the device, while 2 represents a side view of the device.

The first exemplary embodiment of the device according to the invention comprises a light source 1, the light of which is coupled into a coupling section 4 of a light guide element 10 through coupling optics 4a. In the exemplary embodiment, the coupling optics 4a is designed such that the incident light from the light source 1 is formed into a parallel light bundle which runs parallel to the longitudinal extent of the first section 4. The course of the light beam is indicated by two light beams 2, 3, which are only intended to represent two parts of the light emission from the light source 1.

The light guide element 10 further comprises a coupling-out section 5, which is formed in one piece with the coupling-in section 4 and has a longitudinal line running perpendicular to this ckung. The decoupling section 5 has a right 5a and left section 5b, which run along a continuous straight line. A deflection element 9 is arranged at the position at which the coupling-in section 4 meets the coupling-out section 5. In the exemplary embodiment, this is designed as a recess in the material of the light guide element 10. The deflection element 9 comprises, in the manner of a prism, two flat surfaces arranged at an angle to one another, which in the exemplary embodiment are at a right angle to one another. The light rays 2, 3 striking the deflection element 9 hit different surfaces and are accordingly deflected in different directions, which is indicated by the further course of the light rays 2, 3 shown. A first light beam 2, that is, a first part of the coupled-in light, is directed to the left into the left-hand section 5b of the light guide element 10, while a second light beam 3, that is, a second part of the coupled-in light, is directed to the right 5a into the out-coupling section 5 of the light guide element 10 Light guide element 10 is guided.

Coupling elements 7, 8 are formed in the coupling-out section 5 of the light guide element 10. In the exemplary embodiment, the coupling-out elements 7, 8 comprise notches or prism-shaped recesses in the light guide element 10. The coupling-out elements 7, 8 are essentially arranged in a plane which is spanned by the longitudinal axes of the coupling-in 4 and coupling-out sections 5 of the light guide element 10. This is particularly popular 2 clear, which shows schematically in a side view the arrangement of the decoupling elements 7 on a common side within the light guide element 10. The arrangement of the outcoupling elements 7, 8 results in the light being coupled out essentially in a common direction, in 2 to the right, is decoupled. The direction of the coupling-out and in particular the diversification of the coupled-out light distribution can be specified in a manner known per se by a suitable design of the coupling-out elements 7, 8.

The coupled out light 3 occurs, as in 2 shown, by a diffuser 14, which is designed in a manner known per se so that structures behind it are essentially not visible or that a coupled-out light distribution is homogenized.

In the exemplary embodiment, one can speak of a “chimney concept” of coupling the light from the light source 1 and the line in the light guide element 10. Instead of positioning the light source 1 at one end of the coupling-out section 5 and a straight line along the longitudinal extent of the coupling-out section 5, in the exemplary embodiment of the invention, the light is coupled in in a central area and distributed by the deflection element 9 into different areas of the coupling-out section 5.

With reference to the 3 and 4 A second exemplary embodiment of the device according to the invention is explained without and with a shielding element. The expansion is largely similar to that above with reference to the 1 and 2 explained first embodiment; Analogous elements are marked with the same reference numerals.

Unlike the one in 1 and 2 In the first exemplary embodiment shown, in the second exemplary embodiment a continuous arrangement of the coupling-out elements 7, 8 is shown over the length of the coupling-out section 5.

In this exemplary embodiment it is provided that a collar surrounding the coupling section 4 can be used as a shielding element 13. This is made of opaque material and in the exemplary embodiment is also colored white, so that, for example, light emerging due to scattering effects does not reach the surroundings of the light guide element 10, but can be absorbed or coupled back in.

At the in 4 The arrangement shown with the shielding element 13 prevents a bright spot from being formed in the area of the deflection element 9 due to additional light emerging.

In reference to 5 A third exemplary embodiment of the device according to the invention is explained in a housing. The expansion is largely similar to the exemplary embodiments explained above; Analogous elements are marked with the same reference numerals.

In addition to those above related to the 1 until 4 In the exemplary embodiment shown here, the elements explained include a housing 12 with a scattering element 11. The scattering element 11 is arranged in the area of the deflection element 9. This means that light from the light source 1, which is coupled in along the longitudinal extent of the coupling-in section 4 of the light guide element 10 and is not directed by the deflection element 9 to the right or left into the coupling-out section 5, hits the scattering element 11. Such an exit of light can occur for example, due to scattering effects, which are undesirable if they lead to increased light intensity in the area of the deflection element 9.

The scattering element 11 is provided with a reflective coating on which the incident light is scattered. This means that scattered light emission is deflected to the sides so that there is no increased intensity of the coupled-out light distribution in this area.

The housing 12 is formed in a manner known per se from plastic, in particular by injection molding, and the scattering element 11 is formed in one piece in the material of the housing 12. In the exemplary embodiment, the housing 12 has a white color, at least in those areas that face the light guide element 10.

In reference to 6 A fourth exemplary embodiment of the device according to the invention is explained. The expansion is largely similar to the exemplary embodiments explained above, but the structure is repeated along the decoupling section 5.

In this exemplary embodiment, a plurality of coupling-in sections 24 are formed on a common coupling-out section 5, which is formed analogously to the exemplary embodiments explained above, into which light emissions from light sources 23 can each be coupled. Coupling optics are also provided here, but are not shown for better clarity. The coupled-in light is guided through the coupling-in section 24 and strikes an associated deflection element 29, which is formed as a prism-shaped recess and is arranged in the extension of each coupling-in section 24. The light is partially guided in opposite directions along the longitudinal extent of the coupling element 5 and coupled out at coupling elements provided there.

This exemplary embodiment allows, in particular, homogeneous illumination of a long line of light or a similar structure, which is formed by the coupling-out section 5 and illuminated by means of coupled-out light. The decoupling section 5 runs straight in the exemplary embodiment, but it can take on practically any shape in which light guidance can be made possible.

The device shown in this exemplary embodiment can also be arranged in a housing.

Reference symbol list

1

light source; LED

2

Ray of light

3

Ray of light

4

coupling section

4a

Coupling optics

5

decoupling section

5a

Decoupling section (right section)

5b

Decoupling section (left section)

7

Coupling structure, decoupling elements

8th

Coupling structure, decoupling elements

9

deflection element; Deflecting prism

10

Light guide element

11

Scatter element

12

Housing

13

Shielding element

14

lens

23

Another light source

24

Further coupling section

29

Deflection element

Claims (9)

Device for generating a light distribution for a vehicle; comprising a light source (1) for generating light emission; and a light guide element (10) with a coupling-in section (4) and an out-coupling section (5); wherein the light emission can be coupled into the coupling section (4); wherein the outcoupling section (5) has a longitudinal extent and is designed to guide the coupled-in light emission along its longitudinal extent; wherein the coupling-out section (5) has coupling-out elements (7, 8) which are designed to couple out the coupled-in light emission perpendicular to the longitudinal extent of the coupling-out section (5); wherein in a transition region from the coupling-in section (4) to the coupling-out section (5) of the light guide element (10), a deflection element (9) is arranged such that a first and a second part of the coupled-in light emission is directed in different directions along the longitudinal extent of the coupling-out section (5 ) are guided, characterized in that a scattering element (11) is formed in the area of the deflection element (9) in an extension of the coupling section (4), the scattering element (11) having a roller-, spherical or ellipsoid-shaped surface with a reflective coating having. Device according to Claim 1 , characterized in that the coupling-in section (4) and the coupling-out section (5) of the light guide element (10) are formed in one piece. Device according to one of the preceding claims, characterized in that the deflection element (9) is designed as a recess with flat surfaces formed in the light guide element (10). Device according to one of the preceding claims, characterized in that the scattering element (11) is formed in a housing (12); wherein the housing (12) is designed to accommodate the light guide element (10). Device according to one of the preceding claims, characterized in that a collimator is arranged between the light source (1) and the coupling section (4) of the light guide element (10) so that the coupled light emission in the coupling section (4) of the light guide element (10) is parallel to a longitudinal extent of the coupling section (4). Device according to one of the preceding claims, characterized by a shielding element (13) surrounding the coupling section (4). Device according to one of the preceding claims, characterized in that the coupling-out elements (7, 8) are arranged essentially in a plane spanned by the coupling-in section (4) and the coupling-out section (5). Device according to one of the preceding claims, characterized in that the decoupling elements (7, 8) are designed to decouple the light distribution into an exterior of the vehicle. Device according to one of the preceding claims, characterized by at least one further coupling section (24), through which a light emission from a second light source (23) can be coupled in; and a further deflection element (29), which is arranged in a transition region from the further coupling-in section (24) to the coupling-out section (5) of the light guide element (10) in such a way that a first and a second part of the coupled-in light emission of the second light source (23) are directed in different directions along the longitudinal extent of the decoupling section (5).

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