DE102018210546A1 - LIGHTING DEVICE, HEADLIGHT AND METHOD - Google Patents

Abstract

A lighting device with optics is disclosed. This has a conversion element, which is connected upstream of a decoupling surface of the optics. A light source is assigned to the conversion element and emits excitation radiation towards the conversion element. The conversion element then at least partially converts the excitation radiation and then couples the radiation out of the optics via the decoupling surface.

Description

The invention is based on a lighting device according to the preamble of claim 1. Furthermore, the invention relates to a method for producing an optical arrangement and a headlight with a lighting device.

A lighting device is known from the prior art which has a large number of light-emitting diodes (LEDs). A respective optic is connected downstream of a respective LED. For example, the lighting device is used for a vehicle, with which radiation emitted by the LEDs can then be projected into a far field. A predetermined light distribution can be achieved in the superposition of the emitted radiation. The optics are part of a projection module. This results in a comparatively flat design. Since a large number of small LEDs are provided instead of a single light source, cooling the lighting device is comparatively simple. If the radiation from the individual LEDs is only slightly superimposed in the far field, individual areas or tiles can be switched on and off in the light distribution by switching the corresponding LEDs on and off. In the case of vehicle lighting, this can be used to implement an adaptive driving beam or low beam (Adaptive Driving Beam (ADB)), which can also be used as accent lighting for general lighting. So that the individual areas of the light distribution illuminated by a respective LED are homogeneous and as compact as possible in the far field, that is to say they sit close together, an exact alignment of the optics with their respective assigned LED is necessary. A parallel offset between the optics and the respective light source would lead to an angular shift in the far field. Tilting the optics to their respective light source would then lead to distortion of the irradiated area in the light distribution.

In order to ensure a precise alignment between a respective optic and the respective light source, it is known in a first approach that the light sources are applied to a substrate using standard methods, such as, for example, using “surface mount device (SMD) soldering”. Then the optics can be individually adjusted with high accuracy to a respective light source, which means a lot of effort. Alternatively, the optics can be formed in one piece as an optics array. After a precise measurement of the position of the optics, the light sources can then be placed correspondingly precisely on the substrate. These two processes disadvantageously require special machines with high setting accuracy, so-called “fine placer”, which only allow a low throughput. In a further approach, elements or design elements, such as a light guide or a light mixing rod, can be provided in a respective optic to increase the tolerances. This usually leads to an increased space requirement and to higher costs. The imaging quality and the optical efficiency can also be impaired.

The object of the present invention is to provide a lighting device and / or a headlight which is simple and inexpensive to produce in terms of device technology and whose emitted radiation can be output precisely. Furthermore, it is an object of the invention to provide a method for producing the lighting device which is inexpensive and simple.

This object with regard to the lighting device is achieved according to the features of claim 1, with regard to the headlamp according to the features of claim 14 and with regard to the method according to the features of claim 15.

Particularly advantageous refinements can be found in the dependent claims.

According to the invention, a lighting device is provided which has an optical system or a projection module. The optics can have at least one coupling surface for at least one light source, in particular a semiconductor light source. Radiation from the assigned light source can be able to be coupled in via the coupling surface. Furthermore, the optics preferably have a decoupling surface. In a further embodiment of the invention, the optics has a conversion element which is connected upstream of the coupling surface and / or the coupling surface. With the conversion element, an excitation radiation can be converted at least partially into a conversion radiation. The conversion radiation can then, for example, be coupled into the optics via the coupling surface and then coupled out via the coupling surface.

This solution has the advantage that the conversion element or the converter is preferably integrated into the optics, that is to say the conversion element can be placed in a position predefined in the optics. The conversion element can then, for example, scatter the excitation radiation from the light source and effectively represent the light source in the sense of the imaging optics. This results in an extremely precise or almost perfect or perfect alignment of the light source with the optics, in particular because the Conversion element is produced in the same manufacturing process as the entire optics, which eliminates positioning errors due to the connection with several components, in particular if the conversion element is formed, for example, by a casting process. There is therefore no need for complex adjustment using special, high-precision machines, as is the case in the prior art explained in the introduction, in order to achieve a good imaging quality of the overall system. There is also no need for optical elements for light mixing, which would require additional space and would generally cost efficiency.

In a further embodiment of the invention, the light source is preferably in the form of a semiconductor light source. This can, for example, emit blue excitation radiation, in which case the conversion element then converts part or at least part of the excitation radiation into, for example, yellow, conversion radiation. The non-converted excitation radiation can be scattered over the conversion element. The scattered excitation radiation together with the scattered conversion radiation then yields useful light, for example white light. The conversion element thus represents a light source, in particular a white one, in a simple manner.

The conversion light, in particular mixed with the blue light, is thus used for the light mixing and for the production of useful light, in particular white light, so that further optical elements for light mixing can be dispensed with.

In a further embodiment of the invention, the optics have a plurality of coupling surfaces for at least one light source in each case. The optics can then have a respective conversion element for a respective coupling-in surface of at least part of the coupling-in surfaces or for all coupling-in surfaces. The respective conversion element can then be connected upstream of the associated coupling area. Thus, the optics are preferably formed in one piece for a plurality or a plurality of light sources, which simplifies a manufacturing process and handling. As a result, a matrix or an array of light sources with associated optics can be produced with comparatively little effort, in which case the light sources in the form of the conversion elements are aligned extremely precisely with the optical elements. Alternatively, it is conceivable for a respective optic to be provided for a respective light source, each having a conversion element for this.

Silicone is preferably used as the material for the optics. This is an optically transparent material with a sufficiently high resistance to high power densities that is also extremely flexible. However, plastics such as polymethyl methacrylate (PMMA), polycarbonate (PC) or glass can also be used for the optics, this depending in particular on a distance, a specific shape of the optics and a radiation intensity / luminance of the LEDs as well as the temperatures and temperature fluctuations that occur can.

A respective coupling-out surface is preferably assigned a respective coupling-out surface, in particular in order to design a lens in each case. In a further embodiment of the invention, it is conceivable that the plurality of coupling surfaces point in the same direction and / or lie in a common plane. It is also conceivable that the coupling surfaces are configured identically.

Preferably, a coupling-in side of the optics, in particular approximately, is designed to be flat, which, for example, enables a printed circuit board or a mounting plate to be mounted on the coupling-in side in a simple manner.

The outcoupling surface or a respective outcoupling surface is preferably convex. For example, the outcoupling surface or a respective outcoupling surface is designed as a dome. The coupling surfaces are preferably spaced apart from one another. Furthermore, the decoupling surfaces are advantageously spaced apart. The coupling surfaces are arranged, for example, as a matrix or array or in a row or several rows or in a column or several columns. If several rows and / or columns are provided, these can also have different numbers of coupling surfaces. The rows and / or columns can also be arranged offset from one another, with the result that the coupling surfaces can be arranged closer to one another (closest packing) in that the rows and / or columns can be arranged closer to one another. The density of the arrangement can also vary within the matrix.

In a further preferred embodiment of the invention, the at least one coupling-in surface or a respective coupling-in surface or at least a part of the coupling-in surfaces delimits one or more recesses or receiving spaces or cavities for arranging the conversion element. The conversion element is thus preferably arranged in the recess. This can help simple way to arrange the conversion element in the optics. Furthermore, the arrangement of the conversion element in the recess leads to a secure mounting of the conversion element and, furthermore, the conversion element is largely protected against external forces. The recess or recesses integrated into the optics or the optic element can preferably be produced in the same manufacturing process as the entire optics, which eliminates positioning errors due to the connection of several components, in particular if the conversion element is introduced into the receiving space, for example by a casting process. This results in an almost perfect or perfect alignment of the light source, i.e. the conversion element, with the optics. It is therefore not necessary to individually align each optical system to the respective light source, since a common optical system is used where the light source (s) in the form of the conversion element can be arranged with high precision through the cutout (s), which leads to a good imaging quality of the overall system.

The recess is preferably cylindrical and / or blind, e.g. also with a square or rectangular cross section. In particular, it can be introduced into the optics from the coupling-in side. In other words, the recess is preferably concave. It can be designed to be open in the direction away from the decoupling surface. For example, the recess has a, in particular flat, bottom surface, which is surrounded by a cylindrical outer surface. It is conceivable that the, in particular respective, recess is arranged coaxially with the main optical axis of its associated coupling-in surface and / or coupling-out surface. Furthermore, it is conceivable that a part, in particular the lateral surface, of the recess is at least partially or completely reflective. The reflective configuration is carried out, for example, by applying a metallization or TiO2 (titanium dioxide). In other words, vertical or approximately vertical walls in the cavities can be designed to be reflective. As a result, radiation which does not radiate in the direction of the coupling-out surface can be reflected back into the cutout in a simple manner in order to increase the efficiency of the light source. The bottom surface of the recess then serves as a coupling surface. If the receiving space is not designed to be reflective, the outer surface or the entire inner surface of the recess can additionally serve as a coupling surface.

In a further embodiment of the invention it can be provided that the main emission direction of the light source points in the direction of the main optical axis of the optics or is provided at a parallel distance from the main optical axis.

The semiconductor light source is designed, for example, as a light-emitting diode (LED). A light-emitting diode (LED) or light-emitting diode can be in the form of at least one individually housed LED or in the form of at least one LED component which has one or more light-emitting diodes. Several LED chips can be mounted on a common substrate ("submount") and form an LED or can be attached individually or together, for example on a circuit board (e.g. FR4, metal core board, etc.) ("CoB" = chip on board). The at least one LED can be equipped with at least one of its own and / or common optics for beam guidance, for example with at least one Fresnel lens or a collimator. Instead of or in addition to inorganic LEDs, for example based on AlInGaN or InGaN or AlInGaP, organic LEDs (OLEDs, e.g. polymer OLEDs) can generally also be used. The LED chips can be directly emitting or have a phosphor located downstream in the beam path. Alternatively, the light-emitting component can be a laser diode or a laser diode arrangement. It is also conceivable to provide an OLED luminescent layer or a plurality of OLED luminescent layers or an OLED luminescent area. The emission wavelengths of the light-emitting components can be in the ultraviolet, visible or infrared spectral range. The light-emitting components can also be equipped with their own converter. The LED chips preferably emit white light in the standardized ECE white field of the automotive industry, for example implemented by a blue emitter and a yellow / green converter.

The light source preferably has an, in particular flat, emission surface. Alternatively or additionally, it is conceivable that the light source is a surface-emitting light source. The light source can then essentially only emit radiation essentially from a flat surface or emission surface. Alternatively, it is conceivable that the light source, in particular the semiconductor light source, is designed as a volume-emitting light source. For example, it has a convex or cylindrical or cuboid emission surface. The emission surface of the light source can then have an end surface section, which points in particular towards the optics. This can be encompassed by a lateral lateral surface section. For example, the lateral surface section can be designed partially or completely in such a way that light does not pass through it to the outside. Thus, for example, the system efficiency can be increased by guiding more light to the conversion element. For example, the lateral surface section is mirrored or encompassed by a, in particular white, frame, with which the volume-emitting light source, a surface-emitting light source can be created. The frame can be produced, for example, using “molding” or potting. In other words, the light source can be designed as a laterally mirrored volume emitter.

In a further embodiment of the invention, the conversion element, viewed in the direction of the main optical axis and / or on its side facing the light source, has a larger area or irradiation area than the emission surface or emission area of the light source, in particular which points towards the conversion element, in particular viewed in the direction of the main optical axis , on. In other words, the conversion element can have a larger dimension than the light source - in particular transverse to the direction of radiation - with which the light source can be placed with a greater tolerance. The emission surface, which can be flat, for example, has a rectangular circumferential shape, for example. A side length of the light source is preferably less than 250 μm or 150 μm or 80 μm or 40 μm or 20 μm, the side lengths for a light source preferably being the same.

In a further embodiment of the invention, reflective structures can be provided in the optics in order to further increase an offset tolerance of the light sources.

A mounting plate or printed circuit board is preferably provided, on which the light sources are mounted. It is also conceivable that a respective light source has its own fastening plate or a submount. Several submounts can in turn be attached to a common mounting plate. The light source is attached to the mounting plate or the submount, for example, by gluing and / or soldering and / or sintering. The fastening plate and / or the submount can be designed as a “ball grid array” or as a ball grid arrangement. The light sources can then be attached, for example, by soldering.

The optics are preferably firmly connected to the mounting plate or the submount, in particular glued. For example, the adhesive is bonded with silicone, siloxane or silazane, in particular with a clear and / or transparent silicone. It is also conceivable to use a non-reflective adhesive if this is necessary for the contrast between the emission of neighboring optics.

The coupling side of the optics preferably serves as a fastening surface or as a fastening side in order to connect the optics to the fastening plate or the submount.

It is also conceivable that the coupling-in side is designed as a total internal reflection (TIR) optic for a respective light source. For example, the recess or a respective recess with the conversion element is then encompassed by one or a respective paraboloid frustum-shaped outer surface of the optics, which then serves as a TIR surface. The paraboloidal frustum-shaped outer surface preferably spreads in a direction towards the decoupling surface. The design as TIR optics leads to an increase in optical efficiency, in particular if volume-emitting light sources are used.

In a further embodiment of the invention it can be provided that the conversion element encompasses the light source. The conversion element is then, for example, pot-shaped or sleeve-shaped and is opened in particular in the direction away from the coupling-out surface. The radiation emitted by the light source can thus be coupled into the conversion element extremely efficiently. This enables efficient coupling in both of the radiation from a surface-emitting light source and from a volume-emitting light source.

In a further embodiment of the invention, the light source can, for example, be arranged at least partially or completely in the recess or, in particular, starting from the fastening plate or the submount, can be immersed. The light source is thus arranged extremely close to the conversion element. Furthermore, the lighting device can thereby be designed to be extremely compact. In addition, the arrangement of the light source in the recess protects it from external forces and environmental influences.

An emission surface of the light source can be in contact with the conversion element, in particular in sections or completely, or adjoin, in particular in sections or in full, in order to efficiently couple radiation into the conversion element. The emission surface of the light source is preferably spaced apart from the conversion element, in particular uniformly. In this way, surface-emitting or volume-emitting light sources can be used in a simple manner, color locations or a color location then being / being independent of the light source position.

In a preferred exemplary embodiment of the invention, the conversion element can be introduced as a layer in the receiving space, which is easy to produce. The conversion element is then preferably arranged on the bottom side of the recess and, starting from the opening of the recess, has, for example, a, in particular essentially, constant depth or thickness. The conversion element is, for example, thinner than the depth of the recess, which creates space for at least partially inserting the light source into the recess. It is also conceivable that the conversion element completely fills the recess.

If the light source is spaced from the conversion element, then a transparent filling compound can be introduced in the space between the conversion element and the light source. This preferably leads to more efficient light decoupling from the light source and to a more efficient light coupling of the light into the conversion element. The filling compound is, for example, an adhesive and / or silicone and / or (a) siloxane (s) and / or a silazane. In terms of device technology, the filling compound is preferably simply poured in, the LED being immersed in the receiving space, for example, before the filling compound has hardened. In other words, a filling compound is provided which is designed in such a way that a more efficient coupling and coupling of the radiation from the light source is made possible.

If, in a preferred exemplary embodiment, the cutout, in particular essentially, is completely filled with the conversion element, then the light source can be provided outside the cutout. The conversion element then has, for example, a flat light entry surface.

A color mixing element or a respective color mixing element is preferably connected downstream of the conversion element or a respective conversion element, for example this being / are provided in or on the optics or downstream of the optics. Color inhomogeneities can be compensated for in a simple manner via the color mixing element, which is designed, for example, as a scatter plate or casting compound.

According to the invention, a method for producing an optical arrangement according to one or more of the preceding aspects is provided. The conversion element is preferably filled into the receiving space or the recess in the optics and can then be cured. Alternatively, it is conceivable that the conversion element is firmly inserted into the optics or alternatively is attached to the optics.

This solution has the advantage that an optical arrangement can be produced in a simple manner, which has a high efficiency and can be produced with comparatively high tolerances.

The light source (s) can be attached to the mounting plate or the submount or the respective submount. When fastening the light sources, the fastening side of the fastening plate or the submount preferably points opposite to the direction of gravity, which leads to simple installation or fastening of the light sources.

In particular after the light sources have been fastened, the fastening plate can be connected to the optics.

When the conversion element or elements are introduced into the recess (s), the opening (s) preferably have the opposite direction of gravity. This enables a simple assembly of the conversion element or elements.

In a further embodiment of the invention, the light source can be immersed or inserted into the recess or a respective light source into a respective recess before the conversion element hardens. Thus, the conversion element can adapt to the shape of the light source if necessary and, at least in sections, rest against the light source, with which extremely efficient radiation from the light source can be coupled into the conversion element. The filling quantity of the conversion element preferably corresponds, in particular essentially, to the volume of the recess minus the volume of the light source or the part of the light source which is provided in the recess. This has the advantage that no empty space is provided in the recess. If the light source is completely immersed in the recess, then the light source is completely encompassed by the conversion element, which leads to extremely efficient light coupling. In other words, the optical cavities can be filled with the converter without curing, that is to say the converter remains viscous. The filling volume can then be smaller than the cavity volume by the chip volume. It is conceivable that with regard to the volume of the recess and / or the filling quantity of the conversion element and / or with regard to the volume of the Certain tolerances are allowed. In particular, tolerance compensation can be made possible via the size of the cutout. Immersing the light source in the respective recess before curing is advantageous for both volume-emitting and surface-emitting light sources, since in both embodiments radiation can be coupled directly into the conversion element. If the position tolerances of the light sources on the mounting plate are selected such that different thicknesses of the conversion element are formed to the side of the light source in the assembled state, this can lead to color inhomogeneities over the radiation angle, in particular in the case of a partial conversion. It is advantageous here if color mixing elements are provided in the optics or at least upstream of the coupling surface and / or downstream of the coupling surface of the optics. It would then also be advantageous, particularly in the case of volume-emitting light sources, for the light sources to be designed to be laterally reflective or mirrored. It would also be conceivable to design the optics in the area of the coupling-in area as TIR optics, with which the optical efficiency can be increased by “collecting” the light emitted laterally by the light source.

In a further preferred embodiment of the method it is conceivable for a stamp to be immersed in the recess or recesses before the conversion element has hardened and before the light source is inserted, in order to create a receiving space for the light source or the respective light source in the recess. The conversion element (s) is then cured, preferably before the stamp is again led out of the recess. The conversion element or elements in question can thus be hardened or at least be dimensionally stable before the stamp is removed. The filling quantity of the conversion element is preferably, essentially, smaller than the volume of the recess. In particular, the filling quantity of the conversion element can be smaller than the volume of the recess minus the volume of the light source. It is thus possible for the light source, which is inserted into the recess, to be at least partially or completely spaced from the conversion element. In other words, the cavities in the optics are not completely filled with the converter. A stamp and a subsequent hardening ensure a uniform converter distribution on the, in particular complete, inside of the recess. The stamp is preferably designed in such a way that the conversion element is in the form of a sleeve or a pot. If the light sources in the inserted state are then spaced from the conversion element, then color locations are advantageously independent of the position of the light source. For example, it is only necessary that the light sources are arranged within the respective cavity. The configuration of the conversion element, in particular the thickness of the conversion element and thus the color locations, can then be influenced via the position of the stamp with respect to the optics or the recess. Such a configuration of the optics is suitable both for surface-emitting light sources and for volume-emitting light sources. Since the conversion elements have hardened, the entire optics can then be moved and, for example, rotated after the stamps have been removed, for example by the openings of the cutouts pointing in the direction of gravity. The optics can then be placed further on the mounting plate, which can point upwards with the light sources. In contrast to the insertion of the light sources in the case of uncured conversion elements, two separate process steps are thus possible. In other words, the filling of the cavity and the placement of the chips can take place in two separate process steps.

As an alternative or in addition to stamping, it is conceivable that the conversion element is preformed, in particular pot-shaped, before being introduced into the recess or the respective recess. The preforming is preferably carried out in such a way that the outer surface of the conversion element rests on the inner surface of the recess, for example non-positively and / or positively and / or materially. The conversion element can, for example, be produced in an injection molding. Furthermore, it is conceivable that the conversion element is designed as a plate and can then rest on the bottom of the recess.

Furthermore, it is conceivable, particularly in place of a stamp or preforming the conversion element, that the conversion element is introduced into the recess by masked spraying.

In a further preferred embodiment of the invention, it can be provided that the recess or a respective recess is partially, that is to say in particular not completely, filled with the conversion element, in particular in the form of a plate. Thus, the conversion element is preferably designed as a layer, in particular with a constant layer thickness. The conversion element can then be held non-positively and / or positively and / or cohesively at the bottom of the recess. In other words, the cavities in the optics are not completely filled with the converter. The conversion element is preferably cured after filling. The filling quantity of the conversion element is preferably such that after the light sources are inserted, they are spaced from the respective conversion element. Conceivable is also that the light sources, in particular on the end face adjoin or abut the conversion element. If the light sources are spaced apart, it is further conceivable that the light sources are already immersed in the recesses before the conversion elements harden by connecting the fastening plate to the optics. Surface-emitting light sources are preferably used here. Alternatively, volume-emitting light sources can also be used which are designed to be laterally reflective. In this embodiment, it is advantageously achieved that the color locations are independent of the position of the light sources if the light sources are arranged within the recess. It is also advantageous that, for example, no stamp is required. A possible direct exit of the excitation radiation from the light sources can depend on the free spaces between the respective light source and the respective conversion element.

Preferably, in particular after the conversion element has hardened, a filler can be introduced into the recess, which filler is then provided, for example, between the respective light source and the respective conversion element. If, for example, the conversion element is pot-shaped, the filler can be introduced within the space delimited by the conversion element. Before the filler has hardened, the light sources are then preferably introduced into the recess. In other words, for more efficient decoupling of light from the light sources, the space between the conversion elements and the light source can be encapsulated with a transparent adhesive. Before the adhesive or filler hardens, the light source is inserted into the recess. Such a configuration is extremely advantageous for surface-emitting light sources and for volume-emitting light sources. The color locations are then preferably independent of the positions of the light sources, it only being necessary for the light sources to be arranged within the cutouts. The coupling efficiency of the light sources can be increased by the filler. The introduction of the filler is advantageous both in the case of cup-shaped conversion elements and in the case of plate-shaped conversion elements. If the conversion element is provided as a plate or a layer, it is conceivable to introduce the filler into the recess before the conversion element hardens, since the layered structure would be maintained due to a sedimentation process. It is also conceivable to introduce the conversion element and the filler together, in which case the converter would collect on the bottom side of the recess due to the sedimentation process. It is also conceivable that the conversion element is introduced after the liquid filler has been introduced, that is to say before it has hardened, which in turn would cause the conversion element to collect at the bottom of the recess during the sedimentation process. All in all, only one curing process is then necessary, that is to say the conversion element and the filler can be cured together.

In a further embodiment of the invention, it is conceivable that the recess (es), in particular essentially, is / are completely filled with the conversion element. The conversion elements can then form a planar surface together with the coupling-in side of the optics in order to mount the light sources. The optics with the hardened conversion elements are preferably placed on the circuit board with the light sources, the light sources, in particular surface-emitting light sources or volume-emitting light sources with lateral reflection, being in contact with the conversion elements, in particular on the end face. It is also conceivable that after the conversion elements have hardened, the respective light source is placed on the respective conversion element, wherein the light sources cannot yet be connected to the fastening plate. The light sources can then be firmly connected to the conversion element, for example by gluing or curing a filler. The optics together with the light sources can then be placed on the mounting plate for further attachment of the light sources. It is also conceivable that the light sources are placed on a submount or connected to a submount before or after they are connected to the conversion element. The optics with the light sources and the respective submounts can then be connected to the mounting plate via the submounts. In this case, tolerances which are higher than if the light sources are connected directly to the fastening plate can also preferably be provided with the fastening plate.

According to the invention, a headlamp is provided with the lighting device according to one or more of the preceding aspects or with the lighting device which is produced by the method according to one or more of the preceding aspects.

The headlight is used, for example, in a vehicle. The vehicle can be an aircraft or a waterborne vehicle or a landborne vehicle. The land vehicle can be a motor vehicle or a rail vehicle or a bicycle. The vehicle is particularly preferably a truck or a passenger car or a motorcycle. The vehicle can also be designed as a non-autonomous or semi-autonomous or autonomous vehicle.

Further areas of application can be, for example, spotlights for effect lighting, entertainment lighting, architectural lighting, general lighting, medical and therapeutic lighting, lighting for horticulture, etc.

• 1a bis 1c in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem ersten Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung,
• 2 in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel,
• 3a bis 3c in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung,
• 4a und 4b in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung,
• 5a und 5b in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiels zusammen mit einem Verfahren zur Herstellung,
• 6a und 6b in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung,
• 7a bis 7c in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung,
• 8a bis 8c in einer schematischen Darstellung ein Verfahren zur Herstellung der Leuchtvorrichtung aus 7a und
• 9a bis 9c in einer schematischen Darstellung eine Leuchtvorrichtung gemäß einem weiteren Ausführungsbeispiel zusammen mit einem Verfahren zur Herstellung.

The invention is to be explained in more detail below on the basis of exemplary embodiments. The figures show:

• 1a to 1c a schematic representation of a lighting device according to a first embodiment together with a method for manufacturing,
• 2 a schematic representation of a lighting device according to a further embodiment,
• 3a to 3c a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing,
• 4a and 4b a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing,
• 5a and 5b a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing,
• 6a and 6b a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing,
• 7a to 7c a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing,
• 8a to 8c in a schematic representation of a method for producing the lighting device 7a and
• 9a to 9c a schematic representation of a lighting device according to a further embodiment together with a method for manufacturing.

According to 1a is a lighting device 1 shown that for a headlight 2 a vehicle can be used, the headlight 2 schematically with a dashed line in 1a is shown. The lighting device 1 has an optic 4 , which consists of a large number of individual optics arranged in a matrix or array 6 is formed, of which only one is provided with a reference symbol for the sake of simplicity. The individual optics 6 are thus connected to one another in one piece. The individual optics 6 each have a decoupling surface 8th on, which is dome-like or knob-like or also in the form of a Fresnel optic. In series with a respective decoupling surface 8th - seen in the direction of an optical main axis - has a respective individual optics 6 a coupling surface 10 , This is the inner surface of a cylindrical or rectangular recess 12 that in a respective individual optics 6 on their from the decoupling surface 8th groundbreaking side. In a further embodiment, the optics 4 , which is approximately plate-shaped, a flat coupling side 14 on, from which the recesses 12 are introduced. This serves as a fastening side or fastening surface for a fastening plate in the form of a printed circuit board 16 ,

On the circuit board 16 is for a respective single optic 6 a light source in the form of an LED 18 attached, for the sake of simplicity only one is provided with a reference number. For attaching the LEDs 18 points the circuit board 16 a particularly flat attachment surface 20 on. This is the circuit board 16 then on the coupling side 14 attached by gluing, for example with clear silicone, or by clamping or screwing. When the circuit board is connected 16 and the optics 4 is a respective LED 18 in a respective recess 12 fully deployed. The front of the LED shows 18 towards the decoupling surface 8th , Furthermore, the LED 18 from the inner wall of the recess 12 , in particular evenly spaced. Between the LED 18 and the optics 6 is in a respective recess 12 a conversion element 22 introduced, only one being provided with a reference symbol for the sake of simplicity. This is according to 1a the LED is shaped like a pot and surrounds it 18 up to their fastening side completely. A respective LED 18 then couples their radiation, for example blue light, as excitation radiation into the conversion element 22 on. The conversion element has a luminescent material as conversion material, the “luminescent material” also being able to be a luminescent material mixture of several individual luminescent materials. A preferred single phosphor can be yttrium aluminum garnet (YAG: Ce) doped with cerium, then with yellow light as conversion radiation. In general, however, another or different individual phosphor (s) is alternatively or additionally possible, for example for the emission of red and / or green conversion light, a different yellow phosphor also being conceivable. About the conversion element 22 the excitation radiation is then partially converted into conversion radiation, it being can be yellow radiation, for example. Both the conversion radiation and the unconverted excitation radiation are above the conversion element 22 scattered. The blue, unconverted excitation radiation and the yellow conversion radiation then result in scattered, white useful light, starting from the conversion element 22 towards the decoupling surface 8th radiates and is coupled out via this.

To manufacture the lighting device 1 out 1a is provided according to 1b the optics 4 to be arranged so that openings of the recesses 12 opposite to the direction of gravity 24 point. The cutouts 12 are then using the conversion element 22 filled, which in this process step has a viscous or dimensionally stable consistency. A fill volume of the conversion element 22 is smaller than or equal to the volume of the recess 12 minus the volume of the LED 18 , see also 1a , Before, after, or in parallel with this step, according to 1c the LEDs 18 on the circuit board 16 assembled, for example by soldering, gluing or sintering. The mounting surface 20 points opposite to the direction of gravity 24 , please refer 1b , for connecting the circuit board 16 with the optics 4 becomes the circuit board 16 rotated so that the mounting surface 20 down in the direction of gravity 24 points, see 1a , Then the circuit board 20 on the optics 4 set, with the LEDs 18 in the recesses 12 and thus into the conversion elements 22 immerse and deform them accordingly. Connecting the circuit board 16 with the optics 4 takes place before the conversion elements 22 are cured.

The embodiment according to 1a is extremely advantageous for both volume-emitting and surface-emitting LEDs 18 , Lateral surfaces of the LEDs would be conceivable 18 , if these are volume-emitting LEDs, reflective or reflective, so that radiation can only be emitted on the front. Alternatively or additionally, the conversion elements would be conceivable 22 Add color mixing elements to compensate for color inhomogeneities.

The lighting device 1 out 1a can be used, for example, as an adaptive light source, for example for a matrix headlight. In particular, the lighting device is conceivable 1 use as adaptive high beam. Every single LED 18 or groups of LEDs 18 can then be controlled separately, for example, and thus switched on and off and dimmed. In combination with a camera system and image processing electronics and / or other sensors, oncoming traffic and vehicles driving ahead can be detected and at least partially hidden. It is also possible to separately illuminate objects recognized by the camera system, such as pedestrians, animals or obstacles, and thus to make the driver aware of them. Through the lighting device 1 are the light sources that come in handy here through the conversion elements 22 are formed, can be arranged extremely precisely to one another in a device-technically simple manner. This allows individual areas in a light field to be controlled extremely precisely by controlling the LEDs 18 be trained as desired.

In 2 is a lighting device 26 shown, in contrast to 1a an optic 28 is formed from a plurality of individual optics. A single lens is a total internal reflection (TIR) lens 32 or designed as a TIR section, which has a single lens in the form of a lens 34 or is connected downstream of a lens section. The look 32 and the lens 34 form a pair of optics, according to 2 a plurality of pairs of optics are provided, which are arranged parallel to each other. The design of a pair of optics is explained below. The TIR optics 32 and the lens 34 are spaced apart, for example. The TIR optics 32 is frustoconical in shape and widens starting from the circuit board 16 , Its truncated cone-shaped outer surface 36 is designed as a TIR surface and reflects radiation to an output surface 38 the TIR optics 32 going towards the lens 34 has. After the exit area 38 is then the lens 34 downstream. The Lens 34 is designed, for example, as a convex lens or converging lens. It is conceivable to provide additional optical elements. In from the starting area 38 groundbreaking face 40 the TIR optics 32 is a recess 42 brought in. In the recess 42 is a conversion element 44 brought in. A respective LED 18 then dips into the recess 42 one and is from the conversion element 44 completely includes. The production takes place according to the embodiment according to the 1a to 1c , The TIR optics 32 and the lens sections 34 are then over bridges 45 integrally connected with each other, the webs 45 to the side of the TIR optics 32 and the lens 34 are provided. The optics are also conceivable 32 and the lens 34 to connect and / or design a respective pair of optics in a different way. With the TIR optics 32 the optical efficiency can be increased by collecting the light emitted from the side. Here too, in order to compensate for possible color inhomogeneities, color mixing elements and the conversion elements are conceivable 44 nachzuschalten.

According to 3a is a lighting device 46 shown, in contrast to the embodiment in 1a recesses 48 have an enlarged diameter and / or a greater depth, the dimensions depending on the LED size. Furthermore there is a respective LED 50 from each conversion element 52 spaced. The respective conversion element 52 is pot-shaped and covers the respective LED 50 , The LEDs 50 can be used as surface emitting LEDs or volume emitting LEDs 50 be trained. In this embodiment, color locations, in particular essentially, are independent of the exact position of the LEDs 50 , in principle it is sufficient for a high color homogeneity that the LEDs 50 inside the recesses 48 lie.

To manufacture the lighting device 46 exhibits the optics 54 according to 3b with their recesses 48 opposite to the direction of gravity 24 , It will then be the conversion elements 52 introduced informally by making them viscous. The cutouts 48 are only partially with the conversion element 52 filled. Subsequently, in a respective recess 48 a stamp, not shown, is immersed around the conversion elements 52 to shape pot-shaped. The stamps can be removed after curing. It is then an even distribution of the conversion elements 52 on the complete inside of the respective recess 48 reached. According to 3c are on the circuit board 16 the LEDs 50 arranged. The LEDs 50 point opposite to the direction of gravity 24 , The look 54 out 3b is then rotated so that the recesses 48 down in the direction of gravity 24 point. Then the optics 54 on the circuit board 16 with which the LEDs 50 in the recesses 48 are arranged.

In the embodiment of the lighting device 46 according to 3a can be filling the recesses 48 with the conversion elements 52 and their curing regardless of the immersion of the LEDs 50 in contrast to the embodiment according to 1a his. This enables two separate process steps for this.

According to 4a is another embodiment of a lighting device 56 shown. In contrast to the embodiment according to 3a are in the spaces between the LEDs 50 and the respective conversion element 52 Filling compounds each in the form of an adhesive 57 introduced to extract the light from the LEDs 50 continue to improve.

To manufacture the lighting device 56 is according to 4b after the conversion elements have hardened 52 please refer 3b , the glue 57 in that of the respective conversion element 52 limited recording space. The circuit board 16 out 3c with the LEDs 50 is then before the glue cures 57 rotated so the LEDs 50 in the direction of gravity 24 point. Then the circuit board 16 with the optics 54 connected, the LEDs 50 in the glue 57 or immerse glue. Then the glue 57 be cured.

The embodiment of the lighting device 56 according to 4a is advantageous for surface emitting LEDs 50 as well as for volume-emitting LEDs 50 ,

In 5a is another embodiment of a lighting device 58 shown. In contrast to the embodiment 3a are elements of conversion 60 each as a layer in the respective recess 48 brought in. The layered conversion elements 60 can then be parallel to the circuit board 16 extend.

To manufacture the lighting device 58 is according to 5b the optics 54 arranged such that the openings of the recesses 48 opposite to the direction of gravity 24 point. Following are the conversion elements 60 filled in, making it a layer on the bottom of the recess 48 accumulate. Following are the conversion elements 60 hardened. The layer thickness is chosen such that according to 5a in the assembled state of the LEDs 50 this from the conversion elements 60 are spaced. Preferably, the lighting device 58 according to 5a for surface emitting LEDs 50 used. Volume-emitting LEDs are also conceivable 50 to be used, which are preferably laterally reflective or mirrored. Advantageously, no stamps are necessary in this embodiment.

In 6a is a lighting device 62 shown, in which, in contrast to the embodiment in 5a , a space between the LEDs 50 and the layered conversion elements 60 with a filler in the form of the adhesive 57 is filled out. This allows light to come out of the LEDs more efficiently 50 be coupled out.

To manufacture the lighting device 62 is according to 6b the optics 54 arranged such that the recesses 48 with their openings opposite to the direction of gravity 24 point. It is then used after the conversion elements have hardened 60 , see also 5b , the glue 57 in a respective recess 48 filled. Then the LEDs 50 according to 6a in the recesses 48 dipped and the circuit board 16 with the optics 54 connected. Then the glue 57 be cured.

With the lighting device 62 according to 6a can preferably surface emitting LEDs 50 be used. Volume-emitting LEDs are also conceivable 50 to use, which are preferably designed laterally reflective.

In 7a is a lighting device 64 shown, in contrast to the embodiment according to 5a the recesses 48 each complete with a conversion element 66 are filled. This creates according to 7c a planar surface from the coupling side 14 together with the outer surfaces of the conversion elements 66 , According to 7a are LEDs 68 then on the outside of the conversion elements 66 attached. In contrast to the embodiment according to 6a are the LEDs 68 large area on the conversion surfaces 66 on. According to 7b become the LEDs 68 before connecting to the conversion elements 66 on the circuit board 16 assembled. According to 7a is the optics 54 then from the circuit board 16 spaced, the LEDs 68 then between the optics 54 and the circuit board 16 are arranged. In the space between the optics 54 and the circuit board 60 For example, transparent silicone can be provided. Preferably, the lighting device 64 with surface emitting LEDs 68 used. Volume-emitting LEDs are also conceivable 68 to use, which are preferably designed laterally reflective. Filling the cutouts 48 with the conversion elements 66 and curing and putting on the LEDs 68 can then take place in two separate process steps, in particular in contrast to the embodiment according to 1a ,

In the 8a to 8c is another method of manufacturing the lighting device 64 out 7a shown. First, the optics 54 according to 8a arranged such that the recesses 48 with their openings opposite to the direction of gravity 24 point. This is followed by the conversion elements 66 filled and hardened, see 8b , After that, according to 8c to a respective conversion element 66 a respective LED 68 set. The intermediate according to 8c can then according to 7a on the circuit board 16 be set and connected to it.

In 9a is a lighting device 70 shown. In contrast to the embodiment according to 7a is between the LEDs 68 and the circuit board 16 for a respective LED 68 a submount 72 intended.

To manufacture the lighting device 70 become the LEDs 68 according to 9c on their respective submount 72 set. This intermediate according to 9c is then according to 9b to a respective conversion element 66 set and connected to it. The intermediate product 9b in turn, according to 9a on the circuit board 16 set.

A lighting device with optics is disclosed. This has a conversion element, which is connected upstream of a decoupling surface of the optics. A light source is assigned to the conversion element and emits excitation radiation towards the conversion element. The conversion element then at least partially converts the excitation radiation and then couples the radiation out of the optics via the decoupling surface.

LIST OF REFERENCE NUMBERS

lighting device 1; 26; 46; 56; 58; 62; 64; 70 headlights 2 optics 4; 28; 54 Single optics 6 outcoupling 8th coupling surface 10 recess 12; 42; 48 coupling side 14 circuit board 16 LED 18; 50; 68 mounting surface 20 conversion element 22; 44; 52; 60; 66 The direction of gravity 24 TIR optics 32 lens 34 Outer casing surface 36 exit area 38 front 40 Stege 45 Glue 57 submount 72

Claims (15)

Luminous device with an optical system (4; 28; 54) which has at least one coupling-in surface (10) for at least one light source (18; 50; 68) and which has at least one coupling-out surface (8), characterized in that the optical system (4; 28; 54) has at least one conversion element (22; 44; 52; 60; 66) which is connected upstream of the coupling surface (10) and / or the coupling surface (8). Illuminating device after Claim 1 , wherein the light source (18; 50; 68) is in the form of a semiconductor light source which emits an excitation radiation, the excitation radiation being at least partially converted into conversion radiation by the conversion element (22; 44; 52; 60; 66). Illuminating device after Claim 1 or 2 , wherein the optics (4; 28; 54) have a plurality of coupling surfaces (10) for at least one light source (18; 50; 68), the optics (4; 28; 54) for a respective coupling surface (10) at least A part of the coupling surfaces (10) has a respective conversion element (22; 44; 52; 60; 66), and the respective conversion element (22; 44; 52; 60; 66) of the respective associated coupling surface (10) and / or coupling surface (8) is connected upstream. Lighting device according to one of the preceding claims, wherein the at least one coupling-in surface (10) or part of the coupling-in surfaces (10) or all coupling-in surfaces (10) has one or in each case one cutout (12; 42; 48) for arranging the conversion element or elements ; 44; 52; 60; 66) limited / limit. Illuminating device after Claim 4 , wherein the recess (12; 42; 48) is designed as a blind hole. Illuminating device after Claim 4 or 5 , wherein the recess (12; 42; 48) is open towards the decoupling surface (8). Lighting device according to one of the preceding Claims 4 to 6 , wherein at least a partial surface of the recess (12; 42; 48) is at least partially or completely reflective. Illuminating device according to one of the preceding claims, wherein the conversion element (22; 44; 52; 60; 66) viewed in the direction of the main optical axis has a larger area than the emission surface of the associated light source (18; 50; 68) viewed in the direction of the main optical axis , Lighting device according to one of the preceding claims, wherein the light source (18; 50; 68) or the light sources (18; 50; 68) are each mounted on one or a common mounting plate (16) or on one or each of a submount (72) is / are attached. Illuminating device after Claim 9 , wherein the submounts (72) are attached to a common mounting plate (16). Illuminating device after Claim 9 or 10 , wherein the optics (4; 28; 54) is connected to the mounting plate (16) or the submount (s) (72). Lighting device according to one of the preceding claims, wherein the conversion element (22; 44; 52; 60; 66) surrounds the light source (18; 50; 68) or has a layer shape. Lighting device according to one of the Claims 4 to 12 , wherein the light source (s) (18; 50; 68) is / are at least partially or completely arranged in the or the respective recess (12; 42; 48), or wherein the light source / s on the conversion element (22; 44; 52; 60; 66) or on the respective conversion element (22; 44; 52; 60; 66) is / are attached and is / are arranged outside the recess (48). Headlamp with a lighting device according to one of the preceding claims. Method for producing a lighting device according to one or more of the Claims 1 to 13 , wherein the conversion element (22; 44; 52; 60; 66) is filled into the recess (12; 42; 48) of the optics (4; 28; 54) and then hardened, or wherein the conversion element (22; 44; 52; 60; 66) is used in the optics (4; 28; 54).

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