Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/60—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution
  • F21S41/67—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution by acting on reflectors
  • F21S41/675—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution by acting on reflectors by moving reflectors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/10—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source
  • F21S41/14—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source characterised by the type of light source
  • F21S41/141—Light emitting diodes [LED]
  • F21S41/147—Light emitting diodes [LED] the main emission direction of the LED being angled to the optical axis of the illuminating device
  • F21S41/148—Light emitting diodes [LED] the main emission direction of the LED being angled to the optical axis of the illuminating device the main emission direction of the LED being perpendicular to the optical axis
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/10—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source
  • F21S41/14—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source characterised by the type of light source
  • F21S41/141—Light emitting diodes [LED]
  • F21S41/151—Light emitting diodes [LED] arranged in one or more lines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/20—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by refractors, transparent cover plates, light guides or filters
  • F21S41/25—Projection lenses
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/60—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution
  • F21S41/65—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution by acting on light sources
  • F21S41/663—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by a variable light distribution by acting on light sources by switching light sources

Definitions

• Electroluminescent diode lighting system and scanning device for motor vehicle headlamp
• the field of the present invention is that of the light projectors and, more particularly, that of projectors for a motor vehicle.
• Motor vehicle headlamps generally include a lighting system that generates and projects light onto a reflector. The light is then sent to a lens to be reversed and returned as a light beam outside the vehicle.
• a first solution mainly mechanical type, is to use in the lighting system, a cutoff mechanism that can hide (or not) a portion of the reflected beam.
• a cutoff mechanism generally comprises a rotary cutoff bar.
• the cut-off bar is electrically actuated to move, on command, between two or more angular positions in which it more or less obscures the light beam.
• This first mechanical solution which is effective and low cost, has the disadvantage of being able to hide a limited number of areas.
• the lighting system of this second solution has the disadvantage of requiring a large number of light-emitting diodes, generally of the order of 20 to 80, which generates a high cost.
• the technology is not completely mature, and in any case less mature than those of conventional light emitting diodes.
• the object of the present invention is to propose a display system which, while making it possible to implement illumination based on light-emitting diodes, does not have the drawbacks, particularly of cost, of the second usual solution mentioned above.
• the invention relates to a lighting system for a motor vehicle headlamp, the lighting system comprising:
• At least one light source comprising at least one light-emitting diode, said light source being configured to be able to be activated and deactivated and being able to generate light radiation when it is activated;
• the scanning device receiving the light radiation generated by the light source and transmitted by the focussing means, the scanning device comprising at least one rotationally movable reflection system and a unit for moving the imaging system; reflection, the scanning device being configured to reflect the light radiation and spatially distribute it by emitting a light beam.
• At least said light source is configured so that a light beam of generally rectangular shape, oriented in a first so-called vertical direction, is emitted, the scanning device is configured to perform a scanning of the shape light beam.
• the scanning device is configured to perform a scanning of the shape light beam.
• Parts of unlit areas are obtained by synchronizing the extinction of the light beam with its scanning, that is to say by deactivating the light source when, during the scanning , the light beam is supposed to be at a part of the area that one wishes not to illuminate.
• the scanning of the rectangular light beam is performed at a very high speed in order to be able to benefit from a retinal persistence, that is to say so that the human eye sees a whole area illuminated despite the sweeping.
• Retinal persistence is a phenomenon that attributes to the human eye a residual image on the retina, usually lasting about 1/25 of a second.
• the motion unit is configured to generate a very high angular velocity scan and preferably at 3000 ° per second.
• the light source comprises a plurality of light-emitting diodes arranged to form a set of diodes having a rectangular shape.
• the reflection system is movable about an axis parallel to said vertical direction.
• the reflection system is configured to perform a complete rotational movement.
• the reflection system has a cylindrical shape provided on its outer periphery with a plurality of mirrors arranged one beside the other around the periphery.
• the reflection system is configured to perform oscillatory rotational movement at a given rotational angle of less than 180 °.
• the moving unit may comprise:
• the present invention also relates to a projector for a motor vehicle comprising at least one lighting system, such as that described above.
• the present invention further relates to a method of controlling such a lighting system for a motor vehicle headlamp.
• said method comprises a control step of synchronizing the activation / deactivation of the light source with the scan of the scanning device, so as to deactivate, if necessary, the light source for at least one given position of the emitted light beam. in order to obtain at least one unlit part in a lighting zone (covered by the lighting system).
• FIG. 1 is a block diagram of a lighting system according to a first embodiment
• FIG. 2 is a graph for illustrating the scanning of a light beam
• FIG. 3 schematically shows an exemplary embodiment of a light source comprising a plurality of light-emitting diodes
• FIGS. 4 and 5 are schematic views, respectively in perspective and in plan view from above, of an exemplary embodiment of the lighting system according to the first embodiment.
• FIG. 6 is a block diagram of a lighting system according to a second embodiment.
• the present invention applies to a projector (not shown) of a motor vehicle, configured to generate a light beam.
• This projector comprises a lighting system 1 as shown schematically in FIG.
• This lighting system 1 is mounted inside a housing (not shown) of the projector, facing a protective glass, to emit a light beam directed towards the road scene located at the front of the motor vehicle.
• the lighting system 1 comprises:
• a light source 2 comprising at least one light emitting diode 3, of LED type (or "LED” for "Light-Emitting Diode”).
• the light source 2 is configured to be able to be activated and deactivated, that is to say that it can be controlled in order to turn on or turn off the light emitting diode (s) 3, and it is able to generate a light radiation. R when activated, with the aid of said light emitting diode (s) 3;
• a focusing means 4 in the focal plane of which the light source 2 is arranged; and a scanning device 5A, 5B which receives the light radiation R generated by the light source 2, reflects it and spatially distributes it by emitting radiation (called light beam F in the context of the present invention) which is projected to the outside the projector.
• the scanning device 5A, 5B comprises at least one rotationally movable reflection system 6A, 6B, and a motion unit 7A, 7B configured to move the reflection system 6A, 6B, as illustrated by an arrow 8A, 8B in phantom in Figures 1 and 6.
• the numerical references associated with the letter A relate to a first embodiment of the scanning device, shown in FIG. 1, while the numerical references to which the letter B is associated relate to a second embodiment shown in FIG. figure 6.
• At least said light source 2 is configured so that a generally rectangular light beam F of general shape is emitted, as shown in FIG. 2.
• This light beam F is oriented (by its length) in a first direction Z said vertical ;
• the scanning device 5A, 5B is configured to perform a scanning of the light beam F (generally of substantially rectangular shape) in a second direction Y said horizontal, which is substantially orthogonal to said vertical direction Z, as illustrated by an arrow B on Figure 2.
• the scan is performed between two extreme positions P1 and P2 represented in fine continuous line.
• the Z direction substantially corresponds to the vertical direction relative to the ground and the Y direction substantially corresponds to a horizontal direction, transversely to the motor vehicle;
• the scanning is carried out at a high speed which is such that it allows a human eye to benefit from retinal persistence, as specified below;
• the activation / deactivation command of the light source 2 is synchronized with the scanning produced by the scanning device 5A, 5B.
• the lighting system 1 is able to provide illumination of a usual global lighting zone (delimited laterally by the positions P1 and P2 of FIG. motor vehicle, while using a reduced number of light-emitting diodes, preferably from 1 to 8 light-emitting diodes.
• the lighting system 1 thus has a reduced cost, especially since it is possible to use conventional electroluminescent diodes (non-laser) which are less expensive.
• the lighting system 1, as described above, is able to create in the lighting zone one or more parts of zone unlit (or at least with reduced lighting).
• This or these zone portions are obtained by synchronizing the extinction of the light beam F at the level of the light source 2 with its scanning, that is to say by deactivating the light source 2 at the moment when, during the scanning, the light beam F is supposed to be at a part of the area that it is desired not to illuminate, as illustrated for a zone portion Z1 in FIG. 2.
• This zone portion Z1 shown in indents includes two lateral positions P2 and P3. successive light beam F rectangular.
• the lighting system 1 is able to create in the lighting zone a plurality of different, unlit (or at least a reduced illumination) area portions, thereby generating dynamic and selective illumination.
• the scanning of the rectangular light beam is therefore performed at a very high speed in order to be able to benefit from a retinal persistence, that is to say so that the human eye sees an entire area lit despite the sweeping.
• the motion unit 7A, 7B is configured to generate a movement of the reflection system 6A, 6B creating a very high angular velocity scan and preferably at 3000 ° per second.
• the lighting system 1 is associated with a control unit (not shown) which controls the synchronization of the activation / deactivation of the light source 2 with the scanning of the lighting device 5, by generating, in the usual way, control commands. appropriate commands which are sent to the light source 2 (and possibly to the motion unit) as a function of the angular position of the emitted light beam.
• the information concerning the areas of area not to be illuminated, which are used to determine these control commands, are generated in the usual way, for example with the aid of an approaching vehicle detection camera.
• the acquisition of this information is outside the scope of the present invention and is not further described.
• the light source 2 comprises a plurality of light-emitting diodes 3 arranged to form a set of diodes 9 having a rectangular shape.
• the set of diodes 9 comprises five light-emitting diodes 3 of identical square shapes.
• the length L of the set of diodes 9 is equal to five times its width /.
• the rectangular shape of the emitted light beam F is created directly by the rectangular shape of the light source 2 generating the light radiation R.
• the light beam F of rectangular shape can be created in different ways, in particular by a particular combination of the light source (diode (s) electroluminescent (s)) and a means shape generation optics (not shown).
• the reflection system 6A, 6B is movable about an axis X which is parallel to said vertical direction Z.
• the reflection system 6A is configured to perform a complete rotational movement, for example in the direction illustrated by an arrow A in Figure 1.
• the reflection system 6A comprises a cylindrical piece 10, having a symmetry of revolution about the axis X, which is provided on its outer periphery 1 1 of a plurality of mirrors 12 (for example eight or sixteen mirrors ), arranged next to each other around the periphery (or circumference). This cylindrical piece 10 is rotated by the moving unit 7A.
• the light radiation R is reflected successively, one after the other, by the mirrors which are arranged next to each other, and at each moment by the mirror which is at a position PO in front of the focusing means 4.
• the direction of emission D of the light beam F varies. This direction is in an angular range of angle ⁇ which preferably has a value of 40 ° or 60 °, that is to say with values of +/- 20 ° or +/- 30 ° from and other a central angular position.
• FIGS. 4 and 5 show a radiator 13 intended to cool the light source 2 provided with a light-emitting diode 3.
• the reflection system 6B comprises a mirror 14 and is configured to perform an oscillatory rotation movement under the action of the motion unit 7B in an angular range has given less than 180 °, for example in an angular range of 40 °.
• the movement unit 7A, 7B may comprise any type of motor capable of implementing the rotation or oscillation movement considered. In a particular embodiment, it may comprise:
• the lighting system 1 generates, using at least the light source 2, a vertical light beam F (in the direction Z) of rectangular shape. Simultaneously, the scanning device 5A, 5B carries out a horizontal scanning of the vertical light beam F, in the direction Y.
• the lighting system 1 thus provides illumination of a usual global lighting zone of a motor vehicle headlamp.
• the scanning of the rectangular light beam F is performed at a very high speed in order to benefit from retinal persistence.
• the lighting system 1 synchronizes the activation and deactivation of the light source 2 with the scan of the scanning device 5A, 5B, so as to deactivate the light source 2 if necessary for at least one given position of the beam emitted in order to obtain at least one unlit part in a lighting zone.
• the lighting system 1 thus generates a controllable dynamic lighting.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Optics & Photonics (AREA)
• Lighting Device Outwards From Vehicle And Optical Signal (AREA)
• Non-Portable Lighting Devices Or Systems Thereof (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=56511745

Family Applications (1)

Country Status (6)

Families Citing this family (2)

Family Cites Families (13)

• 2016
  • 2016-05-17 FR FR1654346A patent/FR3051540B1/fr not_active Expired - Fee Related
• 2017
  • 2017-05-11 JP JP2018560055A patent/JP6884161B2/ja active Active
  • 2017-05-11 EP EP17727300.0A patent/EP3458772A1/de not_active Withdrawn
  • 2017-05-11 US US16/302,045 patent/US20190154227A1/en not_active Abandoned
  • 2017-05-11 WO PCT/FR2017/051147 patent/WO2017198931A1/fr unknown
  • 2017-05-11 CN CN201780036947.XA patent/CN109477622B/zh not_active Expired - Fee Related

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