Projection apparatus, lighting module and motor vehicle headlamp consisting of micro-optical systems
11280463 · 2022-03-22
Assignee
Inventors
Cpc classification
F21S41/265
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21S41/143
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V5/004
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21W2102/16
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21S41/43
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F21S41/265
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V5/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
Disclosed is a projection apparatus (2) for a lighting module (1) of a motor vehicle headlamp, the projection apparatus (2) being formed by a plurality of micro-optical systems (3) that are arranged like a matrix; each micro-optical system (3) includes a micro-input optical element (30), a micro-output optical element (31) associated with the micro-input optical element (30), and a micro-diaphragm (32), all micro-input optical elements (31) forming an input optical unit (4), all micro-output optical elements (31) forming an output optical unit (5), and all micro-diaphragms (32) forming a diaphragm device (6); the diaphragm device (6) is disposed in a plane extending substantially perpendicularly to the main direction of emission (Z) of the projection apparatus (2), while the input optical unit (4), the output optical unit (5) and the diaphragm device (6) are disposed in planes extending substantially parallel to one another; the micro-diaphragm (32) of each micro-optical system (3) has an optically effective edge (320, 320a, 320b, 320c, 320d, 320e), all of the micro-optical systems (3) are subdivided into at least two micro-optical system groups (G1, G2, G3), and the optically effective edges (320, 320a, 320b, 320c, 320d, 320e) in the micro-optical systems (3) from different micro-optical system groups (G1, G2, G3) are positioned differently relative to the associated micro-output optical elements (31) within the intermediate image plane.
Claims
1. A projection apparatus (2) for a light module (1) of a motor vehicle headlamp, the projection apparatus comprising: a multiplicity of micro-optical systems (3) arranged in a matrix-like manner, wherein each micro-optical system (3) has a micro-entrance optical element (30), a micro-exit optical element (31) assigned to the micro-entrance optical element (30) and a micro-diaphragm (32), wherein all micro-entrance optical elements (30) form an entrance optical element (4), all micro-exit optical elements (31) form an exit optical element (5) and all micro-diaphragms (32) form a diaphragm device (6), wherein the diaphragm device (6) is arranged in a plane, which is orthogonal to a main radiation direction (Z) of the projection apparatus (2) in an intermediate image plane, and wherein the entrance optical element (4), the exit optical element (5) and the diaphragm device (6) are arranged in planes which are substantially parallel to one another, wherein the micro-diaphragm (32) of each micro-optical system (3) has an optically active edge (320, 320a, 320b, 320c, 320d, 320e), wherein the totality of the micro-optical systems (3) is divided into at least two micro-optical system groups (G1, G2, G3), wherein for the micro-optical systems (3) made from different micro-optical system groups (G1, G2, G3), the optically active edges (320, 320a, 320b, 320c, 320d, 320e) are positioned differently relative to the respective micro-exit optical elements (31) inside the intermediate image plane, wherein the micro-diaphragms (32) of each micro-optical system group (G1, G2, G3) are combined to form a micro-diaphragm group (MG1, MG2) and the micro-diaphragm groups (MG1, MG2) are constructed identically, wherein the micro-diaphragm groups (MG1, MG2 are displaced in the vertical direction with respect to one another, and wherein in different micro-optical system groups, (G1, G2, G3), the optically active edges (320, 320a, 320b, 320c, 320d, 320e) are positioned at the same height relative to the respective micro-entrance optical elements (30), wherein the micro-entrance optical elements (30) have differently running optical axes, relative to the respective micro-exit optical elements (31).
2. The projection apparatus according to claim 1, wherein it is (G1, G2, G3) true for each micro-optical system (3) inside the same micro-optical system group (G1, G2, G3) that the optically active edge (320, 320a, 320b, 320c, 320d, 320e) of the micro-diaphragm (32) is displaced relatively to the micro-exit optical element (31) by a distance (h1, h2, h3, h4) vertically and/or horizontally and this distance (h1, h2, h3, h4) is the same for all micro-optical systems (3) inside the same micro-optical system group (G1, G2, G3), wherein the distance (h1, h2, h3, h4) is approximately 0 mm to approximately 0.1 mm.
3. The projection apparatus according to claim 2, wherein the distance (h1, h2, h3, h4) is approximately 0.01 mm to approximately 0.1 mm.
4. The projection apparatus according to claim 3, wherein the distance (h1, h2, h3, h4) is approximately 0.03 mm to approximately 0.06 mm.
5. The projection apparatus according claim 1, wherein the optically active edges (320, 320a, 320b, 320c, 320d, 320e) of at least a portion of the micro-optical systems (3) of each micro-optical system group (G1, G2, G3) are constructed for generating a continuously horizontal or vertical partial cut-off line or a partial cut-off line with an asymmetric rise, wherein each such optically active edge (320, 320a, 320b, 320c, 320d, 320e) is constructed for generating a continuously horizontal or vertical micro-cut-off line (3200) or a micro-cut-off line with an asymmetric rise (3201).
6. The projection apparatus according to claim 1, wherein each micro-diaphragm (32) is constructed as a small plate made from a non-transparent material with an opening (321, 321a, 321b, 321c, 321d, 321e).
7. The projection apparatus according to claim 1, wherein in different micro-optical system groups (G1, G2, G3), the micro-entrance optical elements (30) are positioned at the same height relative to the respective micro-exit optical elements (31) and have a common optical axis.
8. The projection apparatus according to claim 1, wherein the micro-optical systems (3) have an image scale of approximately 3° per 0.1 mm.
9. The projection apparatus according to claim 1, wherein the different micro-optical system groups (G1, G2, G3) are constructed separately from one another and are spaced from one another.
10. A light module (1) for a motor vehicle headlamp comprising: the projection apparatus (2) according to claim 1; and a light source (7), wherein the projection apparatus (2) is downstream of the light source (7) in the light radiation direction and the light generated by the light source (7) is projected with a cut-off line (80) into a region in front of the light module in the form of a light distribution (8), wherein the light distribution is formed from a multiplicity of mutually overlapping partial light distributions with a partial cut-off line in each case, wherein each partial light distribution is formed by exactly one micro-optical system group and the partial cut-off lines together form the cut-off line (80).
11. The light module according to claim 10, wherein the partial cut-off lines are displaced by an angle with respect to one another along a vertical and/or horizontal, wherein the angle has a value of approximately 0° to approximately 3°.
12. The light module according to claim 11, wherein the angle has a value of approximately 2°.
13. The light module according to claim 10, wherein the partial cut-off lines run substantially in a straight line or have an asymmetric rise.
14. The light module according to claim 10, wherein the light source (7) is configured to generate collimated light.
15. The light module according to claim 10, wherein the light source (7) comprises a light-collimating optical element (9) and a semiconductor-based lamp element (10), which is upstream of the light-collimating optical element (9).
16. The light module according to claim 15, wherein the semiconductor-based lamp element (10) is an LED light source, and/or the light-collimating optical element (9) is a collimator, a light-collimating adapter optical element, or a TIR lens.
17. The light module according to claim 10, wherein the light source (7) has at least two light-emitting regions (70, 71, 72), wherein each individual light-emitting region can be controlled independently of the other light-emitting regions of the light source (7), and at least one micro-optical system group (G1, G2, G3), is assigned to each light-emitting region (70, 71, 72) in such a manner that light generated by the respective light-emitting region (70, 71, 72) impinges directly and only onto the micro-optical system group (G1, G2, G3) assigned to this light-emitting region (70, 71, 72).
18. A motor vehicle headlamp comprising at least one light module according to claim 10.
19. The projection apparatus according claim 1, wherein the differently running optical axes are displaced vertically and/or horizontally with respect to one another.
20. A light module (1) for a motor vehicle headlamp comprising: a projection apparatus (2) for a light module (1) of a motor vehicle headlamp, the projection apparatus comprising: a multiplicity of micro-optical systems (3) arranged in a matrix-like manner, wherein each micro-optical system (3) has a micro-entrance optical element (30), a micro-exit optical element (31) assigned to the micro-entrance optical element (30) and a micro-diaphragm (32), wherein all micro-entrance optical elements (30) form an entrance optical element (4), all micro-exit optical elements (31) form an exit optical element (5) and all micro-diaphragms (32) form a diaphragm device (6), wherein the diaphragm device (6) is arranged in a plane, which is orthogonal to a main radiation direction (Z) of the projection apparatus (2) in an intermediate image plane, and wherein the entrance optical element (4), the exit optical element (5) and the diaphragm device (6) are arranged in planes which are substantially parallel to one another, wherein the micro-diaphragm (32) of each micro-optical system (3) has an optically active edge (320, 320a, 320b, 320c, 320d, 320e), wherein the totality of the micro-optical systems (3) is divided into at least two micro-optical system groups (G1, G2, G3), wherein for the micro-optical systems (3) made from different micro-optical system groups (G1, G2, G3), the optically active edges (320, 320a, 320b, 320c, 320d, 320e) are positioned differently relative to the respective micro-exit optical elements (31) inside the intermediate image plane, and wherein the micro-diaphragms (32) of each micro-optical system group (G1, G2, G3) are combined to form a micro-diaphragm group (MG1, MG2) and the micro-diaphragm groups (MG1, MG2) are constructed identically, wherein the micro-diaphragm groups (MG1, MG2 are displaced in the vertical direction with respect to one another; and a light source (7), wherein the projection apparatus (2) is downstream of the light source (7) in the light radiation direction and the light generated by the light source (7) is projected with a cut-off line (80) into a region in front of the light module in the form of a light distribution (8), wherein the light distribution is formed from a multiplicity of mutually overlapping partial light distributions with a partial cut-off line in each case, wherein each partial light distribution is formed by exactly one micro-optical system group and the partial cut-off lines together form the cut-off line (80), and wherein the partial cut-off lines are displaced by an angle with respect to one another along a vertical and/or horizontal, wherein the angle has a value of approximately 0° to approximately 3°.
21. The light module according to claim 20, wherein the angle has a value of 1° to 3°.
Description
(1) The invention, together with further advantages is explained in more detail in the following on the basis of exemplary embodiments, which are shown in the drawing. In the figures
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(12) The figures are schematic illustrations, which only show those constituents which may be helpful for an explanation of the invention. The person skilled in the art will recognize immediately that a projection apparatus and a light module for a motor vehicle headlamp may have a multiplicity of further constituents, which are not shown here, such as setting and moving apparatuses, electrical supply means and many more.
(13) To facilitate readability and where it is expedient, the figures are provided with reference axes. These reference axes relate to a proper installation position of the subject matter of the invention in a motor vehicle and represent a motor-vehicle-based coordinate system.
(14) Furthermore, it should be clear that direction-related terms, such as “horizontal”, “vertical”, “top”, “bottom”, etc. are to be understood in a relative meaning in connection with the present invention and relate either to the above-mentioned proper installation position of the subject matter of the invention in a motor vehicle or to a proper alignment of a radiated light distribution in the light image or in the traffic space.
(15) Thus, neither the reference axes nor the direction-related terms are to be construed as limiting.
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(17) Furthermore, the micro-diaphragm 32 of each micro-optical system has an optically active edge 320, 320a, 320b, 320c, 320d, 320e. Preferably, the optically active edge is likewise in the micro-intermediate image plane 322. The optically active edge 320, 320a, 320b, 320c, 320d, 320e can be set up or constructed to create a cut-off line of a micro-light distribution—a so-called micro-cut-off line 3200, 3201—(cf.
(18) According to the invention, the totality of the micro-optical systems 3 is divided into at least two micro-optical system groups G1, G2, G3. The individual micro-optical system groups G1, G2, G3 differ in that they comprise micro-optical systems 3, the optically active edges 320, 320a, 320b, 320c, 320d, 320e of which are positioned differently relatively to the respective micro-exit optical elements 31 inside the intermediate image plane 322, for example are displaced vertically and/or horizontally. In this case, it is expedient, if the position of the optically active edges 320, 320a, 320b, 320c, 320d, 320e relative to the respective micro-exit optical elements 32 inside the same micro-optical system group G1, G2, G3 is the same.
(19) For example, the micro-diaphragms 32 inside a micro-optical system group, e.g. G1, may be positioned in such a manner in their totality that they do not have any vertical and/or horizontal displacement relative to the respective micro-exit optical elements 31—this leads to centred micro-optical systems 3 for example (see below). If the optically active edges 320b, 320d of these micro-diaphragms 32 are for example set up to form micro-cut-off lines 3200, 3201 for a dipped-beam distribution, as shown for example in
(20) It should be clear that the above-described example is not limited to cut-off lines of dipped-beam distributions, but rather may be generalized to generic light/dark transitions.
(21) How the positionings at different heights of the optically active edges 320, 320a, 320b, 320c, 320d, 320e relative to the respective micro-exit optical elements 31 can be achieved may be explained plausibly for example with reference to
(22) If one for example displaces either the micro-diaphragm 32 or the micro-exit optical element 31 of
(23) Returning to
(24) The different micro-optical system groups G1, G2, G3 may also be arranged above or below one another, as can be seen in
(25) The projection apparatus 2 may also comprise a plurality of micro-optical system groups.
(26) For each individual micro-optical system group G1, G2, G3, it may be expedient if it is true for each micro-optical system 3 inside this one micro-optical system group G1, G2, G3, that the optically active edge 320, 320a, 320b, 320c, 320d, 320e of the micro-diaphragm 32 is displaced vertically by the distance h1, h2 relatively to the micro-exit optical element 31 and this distance h1, h2 is the same for all micro-optical systems 3 inside the same micro-optical system group G1, G2, G3, wherein the distance h1, h2 is preferably approximately 0 mm (see the micro-optical system group G1 of
(27) A distance, which is equal to zero, such as for example h1 in
(28) As mentioned previously, the optically active edges of at least a portion of the micro-optical systems 3 of each micro-optical system group G1, G2, G3 may be constructed to create a continuously horizontal cut-off line 3200—e.g. the edges 320a, 320c or 320e in
(29) Furthermore, it can be seen from
(30) In particular, it can be seen in
(31) As mentioned previously, the micro-entrance optical elements 30 of different micro-optical system groups G1, G2, G3 are positioned at the same height relative to the respective micro-exit optical elements 31 and preferably have a common optical axis OA. In this case, the micro-diaphragms which belong to different micro-optical system groups G1, G2, G3 and can be combined in different micro-diaphragm groups MG1, MG2, are positioned differently (for example displaced vertically and/or horizontally with respect to one another). It can be seen from
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(33) As mentioned previously,
(34) The micro-optical systems 3 may for example have an image scale of approximately 3° per 0.1 mm. Other image scales are conceivable and depend on the respective design of the micro-optical systems 3. That is to say that a relative displacement of the optically active edge 320, 320a, 320b, 320c, 320d, 320e to the micro-exit optical element 31 in such a micro-optical system 3 by approximately 0.1 mm leads to a displacement of a light/dark transition, for example a micro-cut-off line, created by this optically active edge 320, 320a, 320b, 320c, 320d, 320e by approximately 3° along the V-V line VV (that is to say in angular space).
(35) At this point, it is noted that the different micro-optical system groups G1, G2, G3 can be constructed separately from one another and preferably spaced from one another. This can be seen in
(36) The illumination device 1 additionally has a light source 7, preferably a semiconductor-based light source, particularly an LED light source, wherein the projection apparatus 2 is downstream of the light source 7 in the light radiation direction Z and the, preferably essentially total, light generated by the light source 7 is projected with a cut-off line 80 into a region in front of the illumination device 1 in the form of a light distribution, for example a near field light distribution or a dipped-beam distribution 8 with or without a sign-light distribution 81 (see
(37) In this case, the partial cut-off lines may be displaced by an angle with respect to one another along the vertical (V-V line VV) or along the horizontal/the horizon (H-H line HH), wherein the angle has a value of approximately 0° to approximately 3°, for example approximately 1° to approximately 3°, preferably of approximately 2°. As a result, an overlay of partial light distributions with differently positioned partial cut-off lines (for example displaced vertically and/or horizontally with respect to one another) is created in the light image. The partial cut-off lines (and ergo the cut-off line of the entire light distribution) may for example run essentially straight or have an asymmetric rise 80.
(38) The light source 7 may be set up to generate collimated light.
(39) Therefore, the light source 7 may have a light-collimating optical element 9 and comprise a semiconductor-based lamp element 10, for example an LED light source, which is upstream of the light-collimating optical element 9 and for example consists of a plurality of, preferably individually controllable, LEDs. In this case, the light-collimating optical element 9 is for example a collimator or a light-collimating adapter optical element (e.g. made from silicon) or a TIR lens.
(40) As can be seen in
(41) Furthermore, at least one, preferably exactly one, micro-optical system group G1, G2, G3 can be assigned to each light-emitting region 70, 71, 72 in such a manner that light generated by the respective light-emitting region 70, 71, 72 impinges directly, i.e. without being refracted, mirrored, diverted on further optically active surfaces, elements or the like, or changing its intensity and/or propagation direction in another manner, and only onto the micro-optical system group G1, G2, G3 assigned to this light-emitting region 70, 71, 72.
(42) In this case,
(43) It can be seen in
(44) The light-emitting regions 70, 71, 72 may for example be constructed as semiconductor-based light sources and comprise one or more LED light sources in particular.
(45) Using a projection apparatus according to the invention, it is for example possible to set, preferably to reduce, the sharpness factor (also termed the “gradient”) of a cut-off line of a dipped-beam distribution or, in general, sharpness of a light/dark transition of a light distribution. This particularly has an advantage if a characteristic size of the micro-entrance optical elements and the micro-exit optical elements, for example the diameter of their light entrance surfaces lies in the micrometre, preferably in the sub-millimetre range. For optical elements/lenses of this size, a softening of the gradient (reduction of the sharpness factor) by means of conventional methods, such as for example applying an optical structure onto light-exit surfaces of the optical elements, is extremely difficult. The sharpness factor can be reduced by means of an above-described projection apparatus according to the invention.
(46) It is noted at this point, that according to ECE regulation no. 112, the sharpness factor currently lies between 0.13 (minimum sharpness) and 0.40 (maximum sharpness).
(47) Furthermore, the light modules according to the invention enable not only a static softening of the gradient (see above), but also a dynamic setting, preferably reduction of the sharpness factor. Dynamic setting is understood to mean setting during the operation of the light module. Examples of light modules which enable dynamic setting are the light modules with a light source having a plurality of light-emitting regions, wherein the light-emitting regions are individually controllable, as described above. For example, the illumination devices of
(48) The relative position according to the invention of the optically active edges 320, 320a, 320b, 320c, 320d, 320e to the respective micro-exit optical elements 31 inside the intermediate image plane can be calculated as a function of a predetermined gradient. As a result, in light modules for example, a softening of the gradient (the sharpness factor) can be achieved.
(49) In conventional illumination devices, the gradient can for example be softened by applying an optical structure onto a lens surface (cf. e.g. WO 2015031924 A1 of the applicant). In this case, one starts from an original (unmodified) light distribution, which has a cut-off line or a light/dark transition with a gradient, which it is worth softening. The aim—the softened gradient—is predetermined. A scattering function is calculated/determined on the basis of this specification. By folding the unmodified light distribution with this scattering function, a modified light distribution is created, which has the softened gradients according to the specification. The scattering function plays the role of a weighting function in this case. The optical structure—in the case of WO 2015031924 A1—the shape of individual elevations on the lens surface, is also calculated on the basis of the scattering function. The optical structure (the individual elevations) is applied onto the lens surface according to this calculation.
(50) As described previously, the sharpness factor in the present invention can be influenced by different relative positions of the optically active edges 320, 320a, 320b, 320c, 320d, 320e to the respective micro-exit optical elements 31. The expensive application of the optical structure onto lens surfaces (milling of one such structure may take up to a day in terms of time for one lens) is therefore no longer necessary. As also described in the above-described method, a gradient is predetermined as target, which for the most part is smaller than the gradient of the unmodified light distribution. A scattering function is calculated/determined on the basis of this specification. This scattering function can then be converted to the relative position of the optically active edges 320, 320a, 320b, 320c, 320d, 320e to the respective micro-exit optical elements 31 inside the intermediate image plane for all micro-optical system groups G1, G2, G3, so that when folding an original (unmodified) light distribution with this scattering function, the light distribution, which has the predetermined gradient, is created. In this case, the basic idea is that a displacement of an optically active edge from its zero position relative to the respective micro-exit optical element causes a corresponding displacement, which is dependent on an image scale for example, of the light distribution or the light image. The zero position is understood to mean a position, in which the optically active edge to the corresponding micro-exit optical element is not displaced and for example is imaged in a micro-dipped-beam distribution as a non-displaced cut-off line. Because a discrete (finite) number of optically active edges is normally present, the folding may be understood as a sum (superimposition) of micro-light distributions (micro-main-beam distributions or micro-dipped-beam distributions) which are correspondingly displaced with respect to one another.
(51) As explained previously, a displacement of the micro-diaphragm relatively to the respective micro-exit optical element represents a displacement of the light image which is dependent on the image scale. Owing to this relationship, the scattering function, which represents a predetermined change of the gradient, can be converted from angle coordinates in the spherical coordinate system ([°]) into Cartesian coordinates [mm]. On the basis of the representation of the scattering function in Cartesian coordinates, it is possible to determine the relative position of the optically active edges 320, 320a, 320b, 320c, 320d, 320e to the respective micro-exit optical elements 31 inside the intermediate image plane in each micro-optical system group G1, G2, G3 and the number of micro-optical systems in each micro-optical system group G1, G2, G3.
(52) For example, a displacement of a light distribution by 2° may correspond to a displacement of the micro-diaphragm by 0.06 mm.
(53) The intensity values may correspond to the number of micro-optical systems in the respective micro-optical system group G1, G2, G3 in this case. That is to say the candela weighting factors are converted to a number of different positions.
(54) The reference numbers in the claims are used solely for better understanding of the present inventions and in no way mean a limitation of the present inventions.
(55) Insofar as it does not necessarily result from the description of one of the above-mentioned embodiments, it is assumed that the described embodiments can be combined with one another as desired. Among other things, this means that the technical features of an embodiment can be combined with the technical features of a different embodiment individually and independently of one another as desired, in order to achieve a further embodiment of the same invention in this manner.