Microlens array comprising a structured optical element

Abstract

The invention relates to a microlens array (16) for a vehicle light (10), comprising a plurality of incident microlenses (18) through which light can enter the microlens array (16); a plurality of exit microlenses (20) through which light can exit the microlens array (16); and a mask (22) having a plurality of mask portions (24) and arranged between the incident microlenses (18) and the exit microlenses (20). A plurality of channels (26) through which light can pass are provided in the microlens array (16). Each channel (26) extends from at least one of the several incident microlenses (18), via at least one of the several mask portions (24), to at least one of the several exit microlenses (20).A structured optical element (50) is provided between the plurality of incidence microlenses (18) and the plurality of exit microlenses (20), which only partially obstructs the passage of light through the microlens array (16). The invention also relates to a vehicle light (10). Figure 2.

Description

Title of the invention: Microlens array comprising a structured optical element

[0001] The present invention relates to a microlens array and a vehicle light comprising a microlens array.

[0002] Microlens arrays having a relatively short focal length are generally used in the automotive industry to reduce the size of vehicle lights, particularly headlights.

[0003] For such applications, the beam profile produced by the microlens array must meet certain standards (which may vary from country to country). Many of these standards define a beam profile with a light / dark boundary above which the light intensity must not exceed a certain value to avoid dazzling other drivers driving in front or approaching from the front.

[0004] When using a microlens array, the beam profile is typically formed by a superposition of a plurality of individual beam profiles that are created by light passing through individual channels of the microlens array.

[0005] An imaging layer (usually a mask arranged between the lenses) is used to tailor the individual beam profiles in the individual channels by blocking some of the light.

[0006] A known technical problem with this technology is the occurrence of projected profiles with undesirable optical effects that can be caused by crosstalk between individual channels (especially when a microlens array is illuminated by incident light that is partially collimated or not entirely parallel to the orientation of the channels). In addition, reflections that occur at interfaces between separate materials comprising other elements of the headlight compound this problem.

[0007] These interferences can lead to undesirable effects in the beam profile of the headlight. In particular, the light intensity above the light / dark limit can be unintentionally increased, which can lead to dazzling of other road users and thus impair road safety in general.

[0008] There is thus a need for microlens arrays and improved vehicle headlights that avoid the aforementioned difficulties.

[0009] The object of the invention is achieved by a microlens array for a vehicle headlight. The microlens array comprises a plurality of microlenses of incidence through which light can enter the microlens array, and a plurality of exit microlenses through which light can exit the microlens array. The microlens array also comprises a mask which has a plurality of mask parts, the mask being arranged between the incidence microlenses and the exit microlenses. A plurality of channels through which light can pass is provided in the microlens array. Each channel extends from at least one of the plurality of incidence microlenses, via at least one of the plurality of mask parts, to at least one of the plurality of exit microlenses. Each channel comprises in particular exactly one incidence microlens, exactly one mask part, and exactly one exit microlens.A structured optical element is provided between the plurality of incident microlenses and the plurality of output microlenses. The structured optical element only partially prevents the passage of light through the microlens array.

[0010] It has been found that by preventing the passage of a portion of the light through the microlens array, undesirable optical effects in the projected profile, in particular those caused by sharp transitions, for example due to a step in the mask, can be significantly reduced. The portion of light that is not prevented from passing through the microlens array can at the same time contribute to the beam profile, in particular to the brightness of the projection. These advantages persist in particular when the microlens array is not illuminated from the front but at an angle.

[0011] A structured optical element within the meaning of the invention may be an at least two-dimensional structure which is made so as to selectively block light in a first zone and to transmit light in a second zone, the edge between the two zones having a distinct two-dimensional shape, for example a finger structure, a zigzag structure, a structure with transmission holes, a structure with blocking points, or an irregular edge between the first and second zones having a random structure.

[0012] The structured optical element is generally provided in addition to a regular structure of the mask portion which is used to form the beam profile to comply with the standards (which may be different from one country to another). As indicated, these standards define a beam profile with the light / dark limit above which the light intensity must not exceed a certain value to avoid dazzling other drivers driving in front or approaching from the front. The structured optical element may more precisely be arranged on a side opposite the regular structure used to form the beam profile in order to comply with the standards.

[0013] The structured optical element can be made to dim the intensity of light passing through the microlens array by means of its structure. The dim is most effective in reducing the occurrence of unwanted optical effects in the beam profile. The intensity can be dimed by means of different structures. The respective structure chosen for dim the intensity depends, among other things, on the specific application (left-hand traffic and right-hand traffic) and a trade-off between manufacturing costs and efficiency. A certain structure may for example have a high efficiency, but its manufacture may be very expensive, so that a different structure that is less expensive to manufacture is chosen, even if its efficiency is lower, provided that the costs are greater than the efficiency.

[0014] In a preferred embodiment, each of the plurality of mask portions includes an edge having two substantially linear sections extending parallel to and offset from each other. The edge further includes a connecting section connecting the linear sections.

[0015] The purpose of the linear sections and the connecting section which may for example be a step connecting the linear sections is to define the shape of the light beam exiting the microlens array, in particular to control the beam profiles on the upper horizontal edge. This is important to avoid excessively high light intensities above the light / dark limit which may cause dazzling of other road users.

[0016] In this context, terms such as "horizontal", "vertical", "top", "upper", "bottom", "lower" etc. are used to indicate different directions and / or orientations in the intended main application, particularly with respect to the installation situation of the microlens array in the headlight of a vehicle. This terminology is used herein solely for the purpose of improving understanding and is not intended to limit the invention.

[0017] In a variant of the microlens array, adjacent linear sections of two neighboring mask parts are offset from each other in a direction perpendicular to the direction of extension of the linear sections and are connected to each other by at least one structured optical element.

[0018] The offset between adjacent linear sections of two neighboring mask parts is a consequence of the aforementioned connecting section which is used to define the individual beam shapes of individual channels. By establishing a connection of the two adjacent linear sections by means of the at least one structured optical element, in particular instead of a sharp step and / or (straight) edge, the occurrence of interference profiles and / or undesirable optical effects in the beam profile can be effectively suppressed or at least reduced.

[0019] It is conceivable that adjacent linear sections of two mask parts neighbors are connected to each other by an edge of the structured optical element, the edge being different from a straight line. It has been found that making the connecting edge between adjacent linear sections, thus creating the structured optical element, is a simple yet effective method of reducing unwanted optical effects in the projected image.

[0020] The edge of the structured optical element may for example be made to comprise several steps. The steps may each be of the order of magnitude of a few micrometers to effectively influence the passing light, and the number of steps may depend on the distance of the offset between adjacent straight-line sections.

[0021] The connecting section connecting the linear sections of the edge is generally a straight line which is inclined relative to the direction of extension of the linear sections. The connecting section extends for example from bottom left to top right, or rather from bottom right to top left, which actually depends on the usage scenario, namely left-hand traffic or right-hand traffic.

[0022] Unlike the connecting section, the structured optical element can generally have an opposite orientation. Alternatively, the orientation of the structured optical element is perpendicular to the direction of extension of the linear sections.

[0023] The edge of the structured optical element differs in any case from a straight (inclined) line, since a straight line generally does not attenuate the intensity of the light passing through the microlens array. Therefore, the effect according to the invention cannot be achieved by means of a straight line, whether it is an inclined straight line or a single step between the adjacent linear sections of two neighboring mask parts.

[0024] In one embodiment, said at least one structured optical element is asymmetrical with respect to an axis, in particular any axis passing through a point arranged at the center of a virtual line connecting the opposite ends of adjacent linear sections of two neighboring mask parts. The axis may in particular be perpendicular to the virtual line. It has been found that avoiding symmetry promotes the suppression of undesirable optical effects in the beam profile.

[0025] In another variant, said at least one structured optical element comprises a finger structure. The edge of the structured optical element may in particular form the finger structure. The finger structure provides an alternation of light-blocking (opaque) areas and light-transmitting (transparent) areas which are adapted to partially prevent the passage of light through the microlens array.

[0026] The finger structure may comprise a plurality of fingers of different lengths and / or widths. The fingers are spaced apart from each other and may extend into the same direction or not. It is conceivable that the size and spacing of the fingers are chosen so as to be exactly adapted to the needs of the desired application. By defining the size and position of an individual finger, it is in particular possible to selectively influence a certain part of the beam profile. The fingers can be straight, curved, parallel to each other or inclined to each other.

[0027] In another embodiment, said at least one structured optical element comprises at least one transmission hole in the mask, said at least one transmission hole being in particular arranged close to an edge of said at least one structured optical element. Said at least one transmission hole may for example be arranged close to the connection of the linear sections of two neighboring mask parts. The several transmission holes are in particular provided in the mask and arranged close to the edge of said at least one structured optical element.

[0028] Additionally or alternatively, said at least one structured optical element may comprise at least one blocking point which is arranged in one of the several mask parts. The blocking point may in particular be arranged in a transmissive or transparent part of the mask part and / or in the vicinity of the connection of the linear sections of two neighboring mask parts.

[0029] Both the transmission holes and the blocking points are technically simple to implement and well suited to partially prevent the passage of light through the microlens array and / or to attenuate the intensity of the light passing through the microlens array, in particular in a defined manner. This is because this depends on the number, size and / or position of the transmission holes and / or blocking points.

[0030] In one variant, said at least one structured optical element is entirely arranged in one of the plurality of channels. The structured optical element thus partially prevents the passage of light through the corresponding channel(s), thereby preventing or reducing undesirable optical effects that might otherwise be caused by the light.

[0031] It is also conceivable that at least one transition zone is provided between two neighboring channels. In other words, the neighboring channels are spaced from each other by means of said at least one transition zone. Alternatively, the neighboring channels are directly neighboring, the neighboring channels have for example a point contact.

[0032] In one embodiment, the structured optical element is entirely arranged in the transition zone. It thus partially prevents the passage of light through the transition zone, for example by crosstalk, thereby avoiding or reducing undesirable optical effects that might otherwise be caused by the light.

[0033] Alternatively, the structured optical element may also be arranged both in the transition zone than in a channel adjacent to the transition zone. The structured optical element can thus effectively influence the passage of light through the channel and the transition zone, thereby avoiding or reducing unwanted optical effects that might otherwise be caused by light.

[0034] In a specific embodiment, the structured optical element may be arranged in a first channel, an adjacent transition zone, and in a second channel joining the adjacent transition zone on the opposite side.

[0035] In fact, the structured optical element can be arranged in two neighboring channels and in an optional transition zone between the neighboring channels.

[0036] In another preferred embodiment, two or more structured optical elements are provided, the structured optical elements being different from one another in their structure. Due to the use of these optical elements with different structures, in particular in different areas of the microlens array, the individual light beams passing through these areas have different shapes. A superposition of these individual beams results, due to their different shape, in a blurred intensity distribution, and not in strongly pronounced undesired optical effects in the (superimposed) beam profile. Said at least two structured optical elements are, for example, arranged in different channels and / or in different transition areas.

[0037] In a variant of the microlens array, said at least one structured optical element has a characteristic size of less than 50 qm. In this context, characteristic size means the dimension of the structures of the structured optical element influencing the transmission or blocking of light, for example the length or width of the fingers in a finger structure and / or the diameter of the transmission holes or blocking points, also called opaque points. It has been found that structures of less than 50 qm, in particular between 3 qm and 30 qm, are easy to manufacture and effectively attenuate the intensity of the light passing through them.

[0038] Alternatively, said at least one structured optical element may have a characteristic size in a range of the wavelength of visible and / or infrared light, in particular between 300 nm and 3 qm.

[0039] When using structured optical elements having such a small characteristic size, the light passing through them is at least partially diffracted. Consequently, the intensity distribution is smoothed out, and the occurrence of distinct undesirable optical effects in the beam profile is eliminated or at least reduced.

[0040] In another embodiment, at least two of the plurality of mask portions differ from one another so as to project different individual beam profiles when light passes through them. By using different mask portions, it is possible to create a variety of different individual beam profiles (e.g. in individual channels), which promotes the elimination of unwanted optical effects in the superimposed grating profile.

[0041] In another variant, at least three of the plurality of mask parts differ from one another so as to project individual beam profiles which gradually differ from one another when light passes through them. The three different mask parts may in particular be arranged in different neighboring channels.

[0042] The different mask parts can for example be arranged from left to right in the microlens array.

[0043] This particular design allows for intentional switching between the projected beam profiles by changing the illuminated areas of the microlens array. For example, it is possible to use many LEDs and to selectively implement them to illuminate different parts of the microlens array, thus creating the different beam profiles.

[0044] The incidence microlenses and / or the exit microlenses are for example cylindrical lenses.

[0045] The object of the invention is also achieved by a vehicle light, in particular a headlight, comprising at least one light source, a collimating optic, and a microlens array as described above. The advantages explained for the microlens array are also valid in a similar manner for the vehicle light.

[0046] Other advantages and characteristics will emerge from the description of the invention which follows and from the accompanying drawings which represent a non-limiting example of embodiment of the invention and in which: - [Fig.l] schematically shows a side view of a vehicle headlight according to the invention; - [Fig.2] shows schematically a front view of part of a first embodiment of a microlens array according to the invention; - [Fig.3] schematically shows a desired beam profile that is to be formed when a vehicle headlight emits light toward a screen arranged at a predetermined distance; - [Fig.4] schematically shows a beam profile with optical effects unwanted; - [Fig.5] shows schematically a front view of part of a second embodiment of a microlens array according to the invention; - [Fig.6] shows schematically a front view of part of a third embodiment of a microlens array according to the invention; - [Fig.7] shows schematically a front view of part of a fourth embodiment of a microlens array according to the invention; - [Fig.8] schematically shows an example of a structured optical element for a microlens array according to the invention; - [Fig.9] shows schematically another example of an optical element structured for a microlens array according to the invention; - [Fig. 10] schematically shows another example of a structured optical element for a microlens array according to the invention; - [Fig.l 1] schematically shows another example of a structured optical element for a microlens array according to the invention; - [Fig. 12] schematically shows another example of a structured optical element for a microlens array according to the invention; - [Fig. 13] schematically shows another example of a structured optical element for a microlens array according to the invention; - [Fig. 14] schematically shows another example of a structured optical element for a microlens array according to the invention; - [Fig. 15] schematically shows another example of a structured optical element for a microlens array according to the invention; and - [Fig. 16] shows schematically an example of several different mask parts arranged in a row.

[0047] [Fig.l] schematically shows a side view of an embodiment of a vehicle light 10 according to the invention. The vehicle light 10 is a headlight and comprises at least one light source 12, for example an LED or an LED matrix. One or more light sources can thus be provided. The vehicle light 10 further comprises a collimating optic 14, for example a Fresnel lens for collimating the light emitted by said at least one light source 12.

[0048] The vehicle light 10 also includes a microlens array 16. The microlens array 16 includes a plurality of incidence microlenses 18 through which light can enter the microlens array 16, and a plurality of exit microlenses 20, through which light can exit the microlens array 16.

[0049] The incidence microlenses 18 and / or the exit microlenses 20 are for example cylindrical lenses.

[0050] The microlens array 16 further has a mask 22 which comprises a plurality of mask parts 24 and which is arranged between the incidence microlenses 18 and the output microlenses 20.

[0051] In the embodiment shown, the mask 22 is arranged in a focal plane of the incidence microlenses 18 and in a focal plane of the output microlenses 20. This is of course not limiting of the invention. In other embodiments, the mask 22 could be arranged closer or further from the incidence microlenses 18 and / or the output microlenses 20 than from their focal plane. This generally depends on the usage scenario and / or the dimensions of the microlens array 16.

[0052] A plurality of channels 26 capable of being crossed by light is produced in the microlens array 16.

[0053] Each of the channels 26 extends in the embodiment from one of the incidence microlenses 18, via one of the mask parts 24, to one of the output microlenses 20. Each incidence microlens 18 is in other words associated with a corresponding output microlens 20, a part of the mask defined as mask part 24 being arranged between them.

[0054] Each of the mask portions 24 shown in [Fig.l] thus defines an image which is projected by the light passing through the channel 26 which presents the respective mask portion 24.

[0055] In the embodiment shown, transition zones 28 are arranged between neighboring channels 26. It is conceivable that light does not pass through these transition zones 28 or only slightly when the microlens array 16 is illuminated from the front (in the direction of the channels 26). A significant amount of light can, however, pass through the transition zones 28 when the microlens array 16 is illuminated from an angle or is illuminated by partially collimated light due to crosstalk and / or reflections. This can lead to undesirable optical effects, as will be explained in detail below.

[0056] [Fig.2] schematically shows a front view of a portion of the microlens array 16 of [Fig.l], for example two neighboring channels 26 and a transition zone 28 between the neighboring channels 26.

[0057] In the embodiment, the mask 22 has a transmissive zone 30, for example an opening which extends over several mask parts 24, in particular in the horizontal direction. As indicated above, the mask parts 24 are the areas of the mask 22 which are associated with the channels 26.

[0058] The transmissive zone 30 is limited in the vertical direction by opaque zones 32 of the mask 22 which, in the vertical direction, are arranged in opposite faces of the transmissive zone 30.

[0059] The mask 22 has a lower edge 34 which is a boundary between the transmissive zone 30 and one of the opaque zones 32 of the mask 22.

[0060] The lower edge 34 has in the respective mask parts 24 a first (substantially) linear section 36 and a second (substantially) linear section 38. The two linear sections 36, 38 extend parallel, i.e. in the horizontal direction. The linear sections 36, 38 are offset from each other in the direction vertical.

[0061] In the respective mask portions 24, the lower edge 34 further comprises a connecting section 39 connecting the first linear section 36 and the second linear section 38. As illustrated, the connecting section 39 is an inclined straight line.

[0062] The objective of this particular design of the mask parts 24 is to create a beam profile suitable for vehicle lights 10, in particular headlights, by selectively preventing the passage of light through the microlens array 15. The connecting section 39 in fact ensures that the beam profile corresponds to the standards relating to regulations and / or official standards as defined by the original equipment manufacturers (OEMs) or level 1 suppliers.

[0063] [Fig. 3] schematically shows a desired beam profile 40 of a vehicle lamp 10, for example a headlight for right-hand traffic. The desired beam profile 40 may be defined by country-specific regulations and / or standards, as indicated above.

[0064] At the upper end, the beam profile 40 has a light / dark limit 42 above which the light intensity must not exceed a certain value to avoid dazzling other drivers driving in front or approaching from the front.

[0065] As shown in [Fig. 3], the light / dark boundary 42 has a lower part 44 on the left and an upper part 46 on the right. This ensures a distribution of light with maximized intensity where it is most needed, in particular on the own traffic lane or to the right of it, so that traffic signs on the right, for example, can be illuminated appropriately. At the same time, glare of drivers of vehicles traveling in front or pedestrians is avoided.

[0066] It is conceivable that the lower edge 34 of the mask 22 defines or at least strongly influences the shape of the light / dark boundary 42. The lower part 44 of the light / dark boundary 42 can in particular be defined by the first linear sections 36, and the upper part 46 be defined by the second linear sections 38.

[0067] It is known from the prior art that in conventional vehicle headlights comprising conventional microlens arrays, optical interference may occur, which may result in an irregular beam profile 40.

[0068] [Fig.4] shows such an irregular beam profile 40 which may for example arise when a microlens array 16 is used with a mask 22 which has a sharp distinct step or corner connecting the first and second linear sections 36, 38 of neighboring channels 26.

[0069] [Fig. 4] shows that the irregular beam profile 40 exhibits undesirable optical effects 48. Due to these optical effects 48, the light intensity above the light / dark boundary 42 may be increased in certain areas, which may result in dazzling other drivers driving in front or approaching from the front.

[0070] To avoid or at least weaken the occurrence of such undesirable optical effects 48, the microlens array 16 shown in [Fig.2] comprises structured optical elements 50 which are provided between the plurality of incidence microlenses 18 and the plurality of output microlenses 20. In the embodiment, the structured optical elements 50 are part of the mask 22.

[0071] As shown in [Fig.2], the structured optical elements 50 are arranged in the transition zones 28, in particular in an area between the neighboring channels 26.

[0072] The structured optical elements 50 connect adjacent linear sections 36, 38 of neighboring mask parts 24 which are offset from each other in a direction perpendicular to the direction of extension of the linear sections 36, 38, namely offset in the vertical direction.

[0073] In the embodiment shown, the structured optical elements 50 are produced by finger structures 52. In this case, edges 54 of the structured optical elements 50 form part of the lower edge 34 of the mask 22.

[0074] The edges 54 of the structured optical elements 50 in fact connect adjacent linear sections 36, 38 of the neighboring mask parts 24 to each other.

[0075] In the embodiment shown, the upper linear section 36 of the left mask portion 24 and the lower linear section 38 of the right mask portion 24 are connected to the edge 54 of the corresponding structured optical element 50 arranged between the mask portions 24. This, however, depends on the usage scenario. The edge 54 of the structured optical element 50 can indeed also be connected to the lower linear section 38 of the left mask portion 24 and to the upper linear section 36 of the right mask portion 24. As indicated above, this depends on whether the application concerns left-hand traffic or right-hand traffic.

[0076] By establishing these connections by means of the finger structures 52 instead of straight lines, large steps in the lower edge 34 of the mask 22 are avoided, which could lead to undesirable optical effects 48 in the beam profile 40.

[0077] [Fig. 2] shows that the finger structures 52 comprise a plurality of fingers 56 of different lengths and widths.

[0078] In the embodiment, the fingers 56 have a characteristic size (their length and their width) between 3 qm and 30 qm.

[0079] As shown in [Fig. 2], all the fingers 56 extend in the same direction, for example the horizontal direction, and are spaced apart from each other. The fingers 56 are for example parallel to each other.

[0080] It is important to note that the structured optical elements 50 only partially prevent the passage of the light with which they are illuminated through the microlens array 16. The portion of the light whose passage through the microlens array 16 is not prevented may contribute to the beam profile 40 of the vehicle light 10.

[0081] By means of their structure, the structured optical elements 50 attenuate an intensity of the light passing through the microlens array 16, thereby reducing interference effects and thus undesirable optical effects 48 in the beam profile 40.

[0082] In the embodiment shown, the respective structure of the structured optical elements 50 is defined by the shape and / or orientation of the finger structure 52 which causes the intensity of the light passing through the microlens array 16 to be dimmed.

[0083] The embodiment of [Fig.2] shows several structured optical elements 50 which differ from each other in their structure.

[0084] The several different structured optical elements 50 can for example be arranged in different areas, in particular in different channels 26 or different transition areas 28, as shown in [Fig. 2]. The individual light beams passing through these different areas thus have different shapes due to the different structured optical elements 50. A superposition of these individual beams results in a faded intensity distribution and is thus useful for avoiding undesirable optical effects 48 in the superimposed beam profile 40.

[0085] [Fig. 5] schematically shows a front view of a portion of a second embodiment of a microlens array 16 according to the invention. The second embodiment corresponds in several important respects to the first embodiment. Therefore, only the differences will be described. The same reference numbers will be used for identical or functionally identical elements.

[0086] In [Fig. 5], the structured optical elements 50 are entirely arranged in the channels 26. The structured optical elements 50 are made so as to partially prevent the passage of a part of the light through the channels 26 in which they are arranged, thus avoiding or reducing the undesirable optical effects 48 which could otherwise be caused by this part of the light.

[0087] A transition zone 28 is also provided between the neighboring channels 26. This transition zone 28 is however optional. The neighboring channels 26 can thus be in direct contact, for example by a point contact.

[0088] [Fig.6] schematically shows a front view of a part of a third embodiment of a microlens array 16 according to the invention. The third embodiment corresponds in several important respects to the first and second embodiments. Thus, only the differences will be described. The same reference numbers will be used for identical or functionally identical elements.

[0089] In [Fig. 6], the structured optical elements 50 are arranged both in the transition zones 28 and in the channels 26 adjacent to the respective transition zones 28. Due to their position, the structured optical elements 50 are made in such a way as to partially prevent the passage of a part of the light through the respective channels 26 and the transition zones 28 in which they are arranged, thereby avoiding or reducing undesirable optical effects 48 which might otherwise be caused by this light.

[0090] It is also conceivable that at least one structured optical element 50 extends along two neighboring channels 26 and the transition zone 28 arranged between the neighboring channels 26.

[0091] [Fig.7] schematically shows a front view of a portion of a fourth embodiment of a microlens array 16 according to the invention. The fourth embodiment corresponds in several important respects to the first, second and third embodiments. Thus, only the differences will be described. The same reference numbers will be used for identical or functionally identical elements.

[0092] The structured optical elements 50 of [Fig.7], similarly to [Fig.5], are entirely arranged in the channels 26.

[0093] In the fourth embodiment, the structured optical elements 50 each comprise a plurality of steps 58 which form part of the lower edges 34 of the corresponding mask parts 24. The steps 58 have a characteristic size, e.g. their height and length, of a few micrometers, which is sufficient to effectively influence the individual light beams passing through the respective channels 26, in which the structured optical elements 50 are arranged.

[0094] As shown in [Fig.7], the structured optical elements 50 generally have an orientation which is opposite to the orientation of the connecting section 39.

[0095] In addition, the structured optical elements 50 are different from a straight line which would not fade the light intensity. Indeed, the fading is obtained by the several steps 58.

[0096] Figures 8 to 15 schematically show other examples of shapes of the structured optical elements 50 which can be used in the microlens arrays 16 according to the invention, in particular for connecting the first linear sections 36 and the second linear sections 38 of different mask parts 24.

[0097] [Fig.8] schematically shows an example of a structured optical element 50 with a finger structure 52 comprising fingers 56 which are aligned horizontally and whose length varies consecutively.

[0098] [Fig.9] schematically shows an example of a structured optical element 50 with a finger structure 52 comprising fingers 56 which are aligned vertically and whose length varies consecutively.

[0099] [Fig. 10] schematically shows an example of a structured optical element 50 with a finger structure 52 comprising fingers 56 which are aligned at an angle of approximately 45° relative to the linear sections 36, 38. It is also possible to choose other angles.

[0100] [Fig. 11] schematically shows an example of a structured optical element 50 with an irregular structure. The structured optical element 50 shown is asymmetrical with respect to an axis 60 passing through a point 62 arranged at the center of a virtual line 64 connecting opposite ends of adjacent linear sections 36, 38 of two neighboring mask parts 24. In [Fig.l 1], the axis 60 is perpendicular to the virtual line 64.

[0101] [Fig. 12] schematically shows another example of a structured optical element 50 similar to the structured optical element 50 of [Fig. 1 1], however having a coarser irregular structure.

[0102] [Fig. 13] schematically shows another example of a structured optical element 50, comprising a plurality of transmission holes 66. The transmission holes 66 may be arranged in an opaque area 32 of the mask 22. In [Fig. 13], the transmission holes 66 are all arranged near the edge 54 of the structured optical element 50.

[0103] [Fig. 14] schematically shows another example of a structured optical element 50 comprising a plurality of blocking points 68. The blocking points 68 may be arranged in the transmissive area 30 of the mask 22, in particular in a mask portion 24 or a transition area 28, e.g. between two mask portions 24. In [Fig. 13], the blocking points 68 are all arranged near the edge 54 of the structured optical element 50.

[0104] [Fig. 15] schematically shows another example of a structured optical element 50 which includes an edge 54 with steps 58 and which is similar to the structured optical elements 50 of [Fig.7].

[0105] The scope of the invention is of course not limited to the specific types of structured optical elements 50 illustrated in Figures 8 to 15. It is possible to use other types of structured optical elements 50, in particular those which are combinations of two or more of the different structured optical elements 50 described.

[0106] All these specific types of structured optical elements 50 however have in common that an intensity of the light passing through the microlens array 16 is dimmed by means of the respective structure of the structured optical elements 50.

[0107] As already indicated above, the structured optical elements 50 are made in addition to the connecting section 39 used to form the beam profile in accordance with regulations / standards. In contrast to the structured optical elements 50, the connecting section 39 must be arranged within the corresponding channel 26. Furthermore, in contrast to the connecting section 39 provided by a straight line, one edge of the structured optical element 50 has a different shape, for example a staircase shape with several steps.

[0108] In another embodiment, the characteristic size of at least one of the structured optical elements 50 used is in the wavelength range of visible and / or infrared light, preferably between 300 nm and 3 pm, in order to use diffraction effects to soften the intensity of light passing through the microlens array 16, thereby avoiding or at least reducing undesirable optical effects 48 in the beam profile 40.

[0109] [Fig. 16] schematically shows several different mask parts 24 arranged in a row. The different mask parts 24 can for example be arranged from left to right in a microlens array 16. In the embodiment, the different mask parts 24 are arranged in different neighboring channels 26.

[0110] As shown in [Fig. 16], the mask portions 24 are distinguished from each other by the size of the transmissive areas 30 and the opaque areas 32. By using, for example, structured optical elements 50 with a finger structure 52 having longer or wider fingers 56 (as illustrated on the right), the size of the transmissive area 30 can be reduced and the size of the opaque area 32 increased.

[0111] It is of course possible to use other structures of the structured optical elements 50 than the finger structure 52, for example combinations of different structures.

[0112] The different mask portions 24 shown in [Fig. 16] project different individual beam profiles 70 as light passes through them.

[0113] In the example, the individual beam profiles 70 projected by the different mask portions 24 illustrated in [Fig. 16] gradually differ from each other. In other words, there is a gradual change of the individual beam profiles 70 (in the example from left to right).

[0114] It is conceivable that in a vehicle lamp 10, the light source 12 may be made to illuminate selective portions of the microlens array 16, and may for example comprise several LEDs which may be selectively switched on or off.

[0115] The light source 12 can in particular be produced to irradiate different channels 26 comprising the different mask parts 24. It is thus possible to select the different beam profiles 70 to be projected and therefore the shape of the superimposed beam profile 40.

Claims

Claims

1. A microlens array for a vehicle lamp (10), comprising: a plurality of incident microlenses (18) through which light can enter the microlens array (16); a plurality of exit microlenses (20) through which light can exit the microlens array (16); and a mask (22) which has a plurality of mask parts (24) and which is arranged between the incident microlenses (18) and the exit microlenses (20); a plurality of channels (26) through which light can pass being provided in the microlens array (16), each channel (26) extending from at least one of the plurality of incident microlenses (18), via at least one of the plurality of mask parts (24), to at least one of the plurality of exit microlenses (20);and a structured optical element (50) being provided between the plurality of incident microlenses (18) and the plurality of output microlenses (20), which only partially prevents the passage of light through the microlens array (16).;

2. The microlens array of claim 1, wherein the structured optical element (50) is formed to attenuate an intensity of light passing through the microlens array (16) by means of its structure.

3. A microlens array according to claim 1 or 2, wherein each of the plurality of mask portions (24) comprises an edge (34) having two substantially linear sections (36, 38) extending in parallel and offset from each other, the edge (34) comprising a connecting section (39) connecting the linear sections (36, 38).

4. A microlens array according to claim 3, wherein adjacent linear sections (36, 38) of two neighboring mask portions (24) are offset from each other in a direction perpendicular to the direction of extension of the linear sections (36, 38), and wherein the adjacent linear sections (36, 38) are connected by said at least one structured optical element (50).

5. A microlens array according to claim 3 or 4, wherein adjacent linear sections (36, 38) of two neighboring mask portions (24) are connected to each other by an edge (54) of the element structured optic (50), and wherein the edge (54) is other than a straight line.

6. The microlens array of claim 5, wherein the edge (54) of the structured optical element (50) comprises a plurality of steps (58).

7. A microlens array according to one of claims 3 to 5, wherein said at least one structured optical element (50) is asymmetrical with respect to an axis (60) extending through a point (62) arranged at the center of a virtual line (64) connecting opposite ends of adjacent linear sections (36, 38) of two neighboring mask portions (24), and wherein the axis (60) is perpendicular to the virtual line (64).

8. A microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) comprises a finger structure (52).

9. A microlens array according to claim 8, wherein the finger structure (52) comprises a plurality of fingers (56) of different lengths and / or widths, wherein the fingers (56) extend in particular in the same direction and are spaced apart from each other.

10. Microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) comprises at least one transmission hole (66) in the mask (22), said at least one transmission hole (66) being in particular arranged near an edge (54) of said at least one structured optical element (50).

11. A microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) comprises at least one blocking point (68) which is arranged in one of the plurality of mask portions (24).

12. A microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) is entirely arranged in one of the plurality of channels (26).

13. Microlens array according to one of the preceding claims, in which at least one transition zone (28) is provided between two neighboring channels (26).

14. A microlens array according to claim 13, wherein the structured optical element (50) is entirely arranged in the transition zone (28).

15. A microlens array according to claim 13, wherein the structured optical element (50) is arranged both in the transition zone (28) and in a channel (26) adjacent to the transition zone (28).

16. A microlens array according to any preceding claim, wherein two or more structured optical elements (50) are provided, and wherein the structured optical elements (50) differ from each other in structure.

17. Microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) has a characteristic size less than 50 qm.

18. A microlens array according to one of the preceding claims, wherein said at least one structured optical element (50) has a characteristic size in the visible light wavelength range.

19. A microlens array according to any preceding claim, wherein at least two of the plurality of mask portions (24) differ from each other so as to project different individual beam profiles when light passes therethrough.

20. A microlens array according to any preceding claim, wherein at least three of the plurality of mask portions (24) differ from one another so as to project individual beam profiles (70) which progressively differ from one another as light passes through them.

21. Vehicle light (10), comprising: at least one light source (12); a collimating optic (14); and a microlens array (16) according to one of the preceding claims.

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