Optical module for a motor vehicle

Abstract

The subject of this invention is an optical module (100) for a motor vehicle, comprising a first optical element (1) and a projection optics device (3). The first optical element (1) includes a plurality of light guides (11, 12), and the projection optics device (3) is arranged at a distance from the first optical element (1) and has a longitudinal optical axis (O). The plurality of light guides are aligned in a sequence perpendicular to the longitudinal optical axis (O) and in the lateral direction. The plurality of light guides includes a plurality of first light guides (11), which are arranged continuously relative to each other by being interposed between a plurality of second light guides (12). The lateral dimension of each of the plurality of first light guides (11) is smaller than the equivalent lateral dimension of each of the plurality of second light guides (12). According to the invention, the plurality of first light guides (11) are generally laterally offset relative to the longitudinal optical axis (O).

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201910033917.4 (filed on January 14, 2019; invention title: optical module for motor vehicle). Technical Field

[0002] This invention relates to an optical module for motor vehicles capable of generating segmented light beams. The invention also relates to a motor vehicle equipped with a headlight comprising at least one such optical module. Background Technology

[0003] In this configuration, the vehicle is equipped with an optical module capable of longitudinally emitting segmented beams, for example, within a single rectangular segment or even multiple rows of square or rectangular segments. These segmented beams are referred to as "multi-beams" or "pixel beams." The projected segmented beam, composed of multiple juxtaposed or overlapping primary beams, corresponds to the projection of an array of images onto a road scene, formed by the rectangular cross-sectional output surfaces of light guides, each associated with a primary primary light source arranged in a sequence. The segmented beams (i.e., beams composed of multiple primary beams) form adaptive beams, where the shape of the projected segmented beams can be modified by selectively turning each primary primary light source on or off, specifically illuminating certain areas of the road ahead of the vehicle while leaving other areas in darkness to avoid dazzling the detected vehicle.

[0004] This optical module is specifically designed for use in front-mounted lighting systems to perform adaptive lighting, also known as "ADB" (an abbreviation for "Adaptive Driving Beam"). This adaptive lighting function is designed to automatically detect road users who may be dazzled by a beam of light emitted by a vehicle's headlights as high beams, and modify the shape of that beam to create a shadow area. This shadow area forms a dark passage within which the detected user is positioned, while continuing to illuminate the road over a wide area on each side of the user. By regulation, the shadow area must be created laterally relative to the optical axis to, for example, prevent dazzling another vehicle traveling in the opposite direction at a distance of 50 meters. Therefore, this shadow area can be formed according to the currently effective European regulation R123, with a lateral offset of 2.8° to 4° and a vertical offset of 0.57° relative to the intersection of the horizontal and vertical lines. It should be understood that this information is given as an example and can be changed due to changes in regulations.

[0005] The advantages of this adaptive lighting feature are multifaceted: ease of use, better visibility compared to low beams, significantly reduced risk of glare, and safer driving.

[0006] More specifically, in addition to the aforementioned primary basic light source array, this optical module typically includes a first optical element and a projection optics. The first optical element comprises multiple light guides arranged opposite to the primary basic light source. The projection optics are configured to shape the light emitted from the primary light source and deflected by the first optical element, thereby forming a modulated illumination beam. The primary basic light source is typically formed by a light-emitting diode (also known as an "LED"). The primary basic light source is arranged on a flat printed circuit board extending in a plane orthogonal to the projection direction of the segmented beam. The light guides of the first optical element extend longitudinally overall, having an input surface for the light emitted from the primary basic light source and an output surface for these light rays at their longitudinal ends. The first optical element is arranged relative to the projection optics such that the output surface of the light guide is substantially arranged in the object focal plane of the projection optics.

[0007] An optical guide is designed to shape the light emitted from a primary fundamental light source into a focused pencil beam in the form of rectangular or square pixels. The output surface of the optical guide, which is essentially arranged in the object-side focal plane of the projection optics, forms an array of secondary fundamental light sources that can be imaged to infinity by the projection optics.

[0008] This optical module requires the projected image from the secondary primary light source to have light distribution and controlled sharpness, so that the segmented beam formed by combining the images from the secondary primary light source is uniform. This is to ensure that the vehicle driver is not disturbed by illumination variations caused by light intensity dispersion, for example, in areas where multiple images from the secondary primary light source overlap.

[0009] As previously mentioned, the adaptive lighting function known as ADB primarily avoids dazzling drivers in dark areas by creating dark bars in the projected segmented beam after turning off one or more primary primary light sources, while maintaining a near-high beam illumination intensity mode. When all primary primary light sources are on, the projected segmented beam corresponds to the high beam beam, illuminating the road scene holistically. To comply with regulations related to high beam illumination, this holistic beam must have maximum and sufficient intensity at its center. In this known context, it is specified that the light guide of the first optical element and the primary primary light sources are arranged such that the light intensity centered on the longitudinal axis is maximized. More specifically, it is known to arrange the first optical element in an optical module such that the light guides participating in the formation of high-resolution secondary primary light sources are arranged on the optical axis of the optical module, so that the image of the highest resolution pixel can be projected onto the road scene at the center of the beam. It should be understood that the surface area of ​​the high-resolution secondary primary light source at the output of the first optical element is smaller than the surface area of ​​the adjacent lower-resolution light source, and a high-resolution secondary primary light source is formed at the output surface of the light guide, which has an output surface area and an input surface area (extended), which are smaller than the input and output surface areas of the adjacent light guide.

[0010] However, in such optical modules including light guides, the projected segmented beams exhibit high levels of parasitic brightness, particularly under the influence of an optical phenomenon known as crosstalk, due to the diffusion of light emitted by primary fundamental sources in all directions and the distance between these primary fundamental sources and the light guides. More specifically, the light rays emitted by the primary fundamental sources are primarily guided by light guides arranged directly opposite to the primary fundamental sources; however, it should be noted that a small fraction of these rays are guided to adjacent light guides, penetrating them through lateral refraction. This portion of the fiber from the light rays emitted by a given source exits the first optical element at the output surface of the light guide, which does not correspond to the input surface opposite to the primary fundamental source. This parasitic light is particularly problematic when it is desirable to implement dark stripes specific to adaptive illumination operation, because light rays emitted from sources that are not turned off may emerge from the first optical element at the output surface of the light guide corresponding to a turned-off source. Clearly, this phenomenon is amplified when the input surface of the light guide is small, and therefore amplified for "high-resolution" secondary fundamental sources.

[0011] However, the generation of dark fringe in the segmented beam of the projection complies with regulations, as mentioned above, which specifically require the fringe to have a lateral offset of 2.8° to 4° relative to the longitudinal axis. As a result, during the creation of the fringe, the light sources that allow the projection of light between the optical axis and the fringe are kept on. These optical axis-centered light sources are corresponding to high-resolution secondary light sources, which, as previously pointed out, further contribute to the occurrence of the parasitic phenomenon described earlier.

[0012] To address this issue, an opaque shutter wall has been installed between each light guide, arranged parallel to the optical axis of the optical module. This prevents light emitted from the light source from penetrating into adjacent light guides that are not directly connected to it, and also prevents light from penetrating light guides directly opposite the light source. While this arrangement can be considered effective, the solution involves the presence and manufacture of additional components within the module, which is detrimental to the module's weight and cost, and complicates module assembly. Summary of the Invention

[0013] The present invention is applicable to this context and aims to provide an optical module with a specific arrangement to overcome this disadvantage.

[0014] Therefore, the present invention provides an optical module for a motor vehicle, the optical module comprising a first optical element and a projection optics device, the first optical element comprising a plurality of light guides, the projection optics device being arranged at a certain distance from the first optical element and having a longitudinal optical axis, the plurality of light guides being aligned in a sequence perpendicular to the longitudinal optical axis and in the lateral direction, the plurality of light guides comprising a plurality of first light guides, the plurality of first light guides being arranged continuously relative to each other by being interposed between a plurality of second light guides, the lateral dimension of each of the plurality of first light guides being smaller than the equivalent lateral dimension of each of the plurality of second light guides.

[0015] According to the present invention, the plurality of first optical guides are generally offset laterally relative to the longitudinal optical axis.

[0016] Equivalent lateral dimension is understood to mean that the change in lateral dimension between the first and second optical guides can be measured with respect to the input or output surfaces of these optical guides, simply by comparing the same surface from one optical guide to another.

[0017] Based on a set of features that can be combined or used independently of each other:

[0018] - At least one-third of the first optical guide is offset relative to the longitudinal optical axis.

[0019] - The first optical guides are arranged in a sequence relative to the longitudinal optical axis, such that all the first optical guides are located on the same side of the longitudinal optical axis.

[0020] - The first optical element sequentially includes a plurality of second optical guides forming a first sub-sequence, a plurality of first optical guides forming a second sub-sequence, and a plurality of second optical guides forming a third sub-sequence, wherein the first sub-sequence has two to four second optical guides, the second sub-sequence has three to eight first optical guides, and the third sub-sequence has four to six second optical guides.

[0021] - The intermediate longitudinal axis of the first light guide is laterally offset by at least 0.5° relative to the longitudinal optical axis of the optical module, and may be between 0.5° and 5°; more specifically, the intermediate longitudinal axis of the first light guide is laterally offset by a value between 2° and 5° relative to the longitudinal optical axis of the optical module, which allows for coverage of the range of angle values ​​as described above, referring to European standards, to form a shadow area to prevent glare to other vehicles; of course, it is understood that the values ​​within this range may vary according to applicable regulations; the intermediate longitudinal axis is understood to be a longitudinal axis parallel to the longitudinal optical axis of the optical module, which passes through the center of the lateral sequence of the first light guide.

[0022] - The first and second optical guides together form an array, which is mainly in the form of a two-dimensional matrix perpendicular to the longitudinal optical axis of the optical module, which passes through the middle of the matrix in a direction relative to the lateral direction.

[0023] Each light guide includes an input surface for light rays emitted from an associated primary base light source and an output surface for light rays, the output surface being arranged in the focal plane of the projection optics.

[0024] - The lateral dimension of the input surface of the first light guide is smaller than the lateral dimension of the input surface of the second light guide.

[0025] - The lateral dimension of the output surface of the first light guide is smaller than the lateral dimension of the output surface of the second light guide.

[0026] - The primary light source is arranged in a plane parallel to the orthogonal emission plane, and all light guides have the same or nearly the same length along the longitudinal optical axis. It should be understood that the light guides arranged at each end of the sequence can be longer.

[0027] - The first optical element is made of a single block comprising the plurality of light guides, the first optical element having a common output surface for light rays passing through one of the plurality of light guides or other light guides.

[0028] - The second optical element can be arranged between the first optical element and the projection optics.

[0029] - The plurality of first light guides are each associated with at least one basic light source to project a first basic beam, and wherein the plurality of second light guides are each associated with a basic light source to project a second basic beam, the projection optics allowing segmented beams to be projected along the longitudinal axis of the vehicle, the segmented beams being formed by the first and second basic beams, and the first basic beams being generally offset relative to the longitudinal axis of the vehicle.

[0030] - The optical module includes a pulse width modulation unit configured to control at least some of the primary primary light sources associated with the first light guide, such that the first and second primary beams arranged at the center of the segmented beams have the same light intensity.

[0031] The subject of this invention also includes a motor vehicle comprising at least one headlight, the headlight comprising the optical module described above.

[0032] The vehicle may have a central longitudinal axis parallel to the direction of travel of the vehicle and include at least one headlight, the headlight including the optical module as described above, and the at least one headlight may be a left headlight, in which case the module according to the invention is arranged such that a plurality of first light guides are generally located between the longitudinal optical axis and the central longitudinal axis of the vehicle. Attached Figure Description

[0033] Other features, details, and advantages of the invention will become more apparent from the following description, given by way of example, with reference to the accompanying drawings, in which:

[0034] - Figure 1 A schematic top sectional view of an optical module according to the present invention is shown. The optical module mainly includes a first optical element, a second optical element, and projection optics along the longitudinal projection axis.

[0035] - Figure 2 A perspective view of a first optical element is shown, which can be mounted with... Figure 1 In the optical module shown, which is consistent with the optical module, the first optical element includes multiple light guides.

[0036] - Figure 3 This is a schematic top view showing the distribution of the light guide of the first optical element relative to the optical axis of the projection optics, which is shown downstream of the first optical element.

[0037] - Figure 4 It is similar to Figure 3 The view shows the path of the light rays used to project the segmented beam in the optical module.

[0038] - Figure 5 It shows something similar to Figure 4 The view shows the first light guide being closed to create a dark channel in the segmented projected beam. Detailed Implementation

[0039] In the remainder of this specification, the following non-restrictive directions will be adopted:

[0040] - Longitudinal L, along the longitudinal optical axis of the projection optics of the optical module and the associated direction of travel of the vehicle, and oriented from back to front relative to the normal direction of travel of the vehicle;

[0041] - Vertical V, along an axis perpendicular to the ground on which the vehicle travels and oriented from bottom to top, serves as a geometric reference and does not necessarily depend on the direction of gravity; and

[0042] - The horizontal T, along the axis perpendicular to the aforementioned longitudinal and vertical axes, is oriented from left to right.

[0043] Also refer to Figure 1 and Figure 4 The diagram shows an optical module 100 designed for mounting on a headlight for a motor vehicle. The optical module 100 is designed to emit a segmented beam oriented longitudinally forward. It is an adaptive beam composed of multiple basic beams 11', 12' (see...). Figure 4 Such an optical module 100 is particularly capable of realizing the function of adaptive beam, also known as "ADB", or "Adaptive Driving Beam". Understandably, it can also realize the function of directional lighting, also known as "DBL", or "Dynamic Bending Light".

[0044] Headlights for motor vehicles include at least one such optical module 100, and it should be understood that other optical modules may be arranged in the same headlight for further implementation of other lighting and / or signal indicator functions.

[0045] The optical module 100 mainly includes a primary basic light source 4, a first optical element 1 with multiple light guides, and a projection optics 3. The projection optics 3 is arranged longitudinally forward and spaced a certain distance from the first optical element 1, and is formed to have a longitudinal optical axis O. Where appropriate, the optical module 100 includes a second optical element 2, referred to as a field correction optical element, which is inserted between the first optical element 1 and the projection optics 3.

[0046] The primary basic light source 4 is formed by light-emitting diodes. The optical module 100 includes at least one row of primary basic light sources 4, which is formed here by a series of light-emitting diodes along the lateral direction T. The primary basic light sources 4 are carried on the front face of the printed circuit board 5.

[0047] The printed circuit board can power the light-emitting diode (LED) and also carry a pulse width modulation unit for controlling the light intensity emitted by the LED, so as to provide a 100% light intensity operating mode and a degraded mode, in which the light intensity emitted is, for example, 80%, which will be described in more detail below.

[0048] The primary light source 4 emits light in all directions, and the arrangement of light-emitting diodes forming these light sources on the printed circuit board produces a very open light-emitting cone, such as a Lambertian light-emitting cone.

[0049] In the case of the optical module 100 designed to transmit segmented light beams, each primary basic light source 4 is associated with a light guide 11, 12, which is specifically arranged in the first optical element 1 to be formatted as a secondary image or secondary basic light source 51, 52 at its output surfaces 11B, 12B (i.e., at its free ends opposite the primary basic light sources), forming square or rectangular pixels. For this purpose, the first optical element 1 is arranged longitudinally in front of the row of primary basic light sources 4 to modify the distribution of emitted light.

[0050] The output surfaces 11B and 12B of the light guide are arranged on the object-side focal plane of the projection optics 3 of the optical module 100. It can then be understood that the first optical element 1 is arranged between the primary base light source 4 and the projection optics 3.

[0051] Before describing the shape and arrangement of the light guide in the first optical element 1 in more detail, the elements arranged downstream of the first optical element, namely the field correction optical element 2 and the projection optical device 3, will be described first.

[0052] The projection optics 3 here is lens-shaped. In a known manner, the projection optics 3 includes an object-side focal plane that extends generally orthogonally to the longitudinal optical axis O, which intersects the object-side focal plane at the object-side focal point of the projection optics 3. Each secondary primary light source 51, 52 is substantially located on the object-side focal plane of the projection optics, with the aim of enabling these secondary light sources to be clearly imaged, and for the segmented beams projected onto the road scene through the projection optics to have the optical characteristics required for its application.

[0053] Theoretically, it is assumed that the projection optics 3 has a flat object-side focal plane that is completely orthogonal to the longitudinal optical axis O. However, in reality, it is known that the projection optics 3 has an object-side focal plane with a concave spherical curvature defect. This defect is called Petzval field aberration.

[0054] In order to correctly focus the projection optics 3 onto the secondary primary light sources 51 and 52, a second optical element 2, called a field correction optical element, is inserted between the emission plane P and the projection optics 3. This second optical element 2 is specifically designed to correct the field curvature aberration of the projection optics 3.

[0055] The second optical element 2 is configured such that, as viewed from the first optical element 1, the image of the curved focal plane of the projection optics 3 extends through the second optical element 2 into the object-side focal plane coinciding with the emission plane P, where the secondary primary light sources 51 and 52 appear. The projection optics 3 is pre-positioned such that the object-side focal plane is tangent to the emission plane P, and the second optical element 2 has the effect of flattening the object-side focal plane toward the emission plane P.

[0056] The second optical element 2 is formed by at least one field correction lens, also known as a "field flat lens". In the example shown, the second optical element 2 includes a single field correction lens. It should be understood that the second optical element 2 may include multiple field correction lenses arranged in series along the optical axis, or other types of lenses, for example, for correcting other optical aberrations such as astigmatism or distortion.

[0057] The second optical element 2 includes an input surface 20 for light, which is longitudinally arranged at a certain distance from the emission plane P. The input surface 20 of the second optical element 2 is longitudinally arranged at a certain distance from the output surface 10 of the first optical element 1 and / or the output surfaces 11B, 12B of the light guide carried by the first optical element. The input surface 20 of the second optical element 2 may have a curved, concave, or convex shape at its center near the longitudinal optical axis O of the projection optics.

[0058] The second optical element 2 also includes an output surface 21 for light, which is arranged longitudinally facing the projection optics 3 and at a certain distance from the projection optics 3, and the output surface 21 has a convex shape.

[0059] Because the second optical element 2 is arranged between the first optical element 1 and the projection optics 3, short light guides 11 and 12 can be produced, which have substantially equal lengths from one lateral end to the other in the sequence. The first optical element 1 is therefore easier to manufacture. In particular, materials that do not allow for the production of long light guides 11 and 12 by molding can be used. Therefore, the first optical element 1 according to the invention can be made of polycarbonate. Of course, it should be understood that, needless to say, the first optical element 1 produced according to the teachings of the invention can be made of glass, silicone, or even polymethyl methacrylate (PMMA) or any other material suitable for producing light guides 11 and 12.

[0060] Simultaneously refer to Figure 1 and Figure 4 The first optical element 1 includes a rear portion 1A and a front portion 1B forming a one-piece assembly.

[0061] The front portion 1B is used to shape the fundamental light beams 11' and 12' emitted by the secondary fundamental light sources 51 and 52. The front portion 1B includes a common output surface 10 for the light rays of the first optical element 1, such that the fundamental light beams 11' and 12' can be propagated vertically and / or horizontally, for example. The front portion 1B is made of components having light guides 11 and 12, such that the first optical element 1 is made as a single block.

[0062] The first optical element 1 includes an array of multiple light guides 11, 12 in its rear portion 1A facing the primary basic light source 4 opposite to the projection optics 3. This array is primarily aligned in the lateral direction T. More specifically, the array is in matrix form, with two lateral rows 112 of the light guides 11, 12 arranged such that one is above the other in a vertical direction perpendicular to the extension direction of the rows. Each light guide 11, 12 is associated with at least one primary basic light source 4. It should be understood that all or part of the light guides, especially those arranged at the lateral ends of the rows, may be associated with multiple primary basic light sources 4.

[0063] The first line is 111, this is... Figure 2 The downward-facing light-emitting diodes (LEDs) that form the primary basic light source 4 and are used to generate the first set of basic beams are positioned opposite each other, such as... Figure 4 and Figure 5 As shown, their lateral juxtaposition helps to form the upper part of the segmented beam projected onto the road, i.e., part of the long-range beam. (Second row, 112, here...) Figure 2 The upper part of the light-emitting diode (LED) is positioned opposite to the primary basic light source 4 (not shown in the figure) for generating the second set of basic beams, and its lateral juxtaposition helps to form the lower part of the segmented beams projected onto the road.

[0064] The remainder of this specification will describe in more detail the arrangement of one of these rows of light guides 11, 12, namely... Figure 2 The downward rows of light guides 11 and 12 shown are understood to be rows capable of emitting a long-range beam of light, which should be controlled to form a dark area. However, without departing from the invention, the following details may apply to the second row of light guides, and may be applied to the other rows of light guides if the optical module is configured to provide at least three rows of light guides.

[0065] The downlink includes two types of optical guides 11 and 12. More specifically, the downlink includes a plurality of first optical guides 11 and a plurality of second optical guides 12, which are distinguished from each other by their lateral dimensions (i.e., dimensions along the principal directions of these sequences of optical guides). The plurality of first optical guides 11 are arranged continuously relative to each other by being interposed between the plurality of second optical guides 12. Furthermore, the respective lateral dimensions of the input surface 11A and output surface 11B of the plurality of first optical guides 11 are smaller than the respective lateral dimensions of the input surface 12A and output surface 12B of the plurality of second optical guides 12.

[0066] In other words, the descending arrangement of a plurality of light guides 11, 12 in the first optical element 1 is configured such that the plurality of light guides 11, 12 are sequentially connected to each other in a lateral order, with at least one first-type light guide 11 distinguished from the others by a smaller lateral dimension. This or these first-type light guides 11 are arranged in a central position, surrounded by second-type light guides 12 (i.e., those with a lateral dimension larger than that of the first-type light guide 11). The central position of the first light guide 11 or the first-type light guide is understood to mean that the second light guide 12 or the second-type light guide is present laterally on each side of these first-type light guides 11, without involving a symmetrical distribution of the second-type light guides 12 around the first-type light guides 11. Furthermore, it should be noted that the second-type light guides may have different dimensions among them, particularly the light guides arranged at the lateral ends of the row, which are much wider and flared.

[0067] Figure 3 The diagram schematically illustrates the lateral sequence of light guides forming a row, here the first row or lower row 111, and their positions relative to the longitudinal optical axis O are defined by the shape of the projection optics 3. According to the invention, the first light guides 11 are generally laterally offset relative to this longitudinal optical axis O. In other words, when the optical module is applied to a left-hand drive vehicle (i.e., for driving on the right) and a right-hand drive vehicle (i.e., for driving on the left), respectively, from inside the vehicle, most of the first light guides are respectively positioned on the right side of the longitudinal optical axis (e.g.,...). Figures 3 to 5 (As shown) or on the left. The path of the light rays output from these light guides through the projection optics will be described later to illustrate the usefulness of this lateral offset of the light guides.

[0068] According to the embodiment shown, the transverse row of the optical guides sequentially includes three second optical guides 12 forming a first subsequence A, eight first optical guides 11 forming a second subsequence B, and five second optical guides 12 forming a third subsequence.

[0069] Each light guide 11, 12 extends along a longitudinal principal axis O1, substantially parallel to the longitudinal optical axis O, from the input surfaces 11A, 12A for light emitted from the primary basic light source 4 to the output surfaces 11B, 12B for the aforementioned light. Each light guide 11, 12 is designed to guide light entering through the input surfaces 11A, 12A all the way to the output surfaces 11B, 12B, in order to form one of the secondary basic light sources 51, 52.

[0070] More specifically, the input surfaces 11A and 12A of the light guides 11 and 12 are arranged in a common plane that is substantially parallel to the plane of the printed circuit board. When the first optical element 1 is arranged in the optical module 100, each input surface 11A and 12A is thus positioned longitudinally facing and close to the associated primary base light source 4, such that most of the light emitted by each primary base light source 4 enters the associated light guide 11 and 12.

[0071] The output surfaces 11B and 12B of the light guides 11 and 12 forming the secondary primary light sources 51 and 52 are arranged in an emission plane P orthogonal to the longitudinal optical axis O. The emission plane P is the object-side focal plane of the projection optics 3, so that the images of the secondary primary light sources 51 and 52 are projected to infinity. It is schematically shown here as a straight plane, but those skilled in the art will know how a curved profile is provided for the emission plane P in the implementation of the present invention.

[0072] As described above, the lateral dimensions of the input surface 11A and the output surface 11B of the first light guide 11 are smaller than the lateral dimensions of the input surface 12A and the output surface 12B of the second light guide 12. More specifically, the lateral dimension of the output surface of the first light guide is smaller than the lateral dimension of the output surface of the second light guide, so as to provide a higher resolution pixel at the output of the first light guide than at the output of the second light guide.

[0073] Therefore, each output surface 11B of the plurality of first light guides 11 has a portion adapted to generate a first fundamental "high-resolution" beam 11' with high light intensity emitted from the first primary fundamental light source 51. Similarly, each of the plurality of second light guides 12 has a portion adapted to generate a second fundamental "low-resolution" beam 12 with low light intensity emitted from the second secondary fundamental light source 52. It is understood that the terms high resolution and low resolution, or high light intensity and low light intensity, are chosen to characterize that one of the fundamental beams has a better resolution than the other, rather than whether it exceeds a given threshold.

[0074] Each first fundamental beam and each second fundamental beam have a desired shape for use in the optical module 100 mounted to the headlight.

[0075] Therefore, the output surfaces 11B and 12B of the light guides 11 and 12 form a row of secondary basic light sources 51 and 52. Each secondary basic light source 51 and 52 is capable of emitting a basic beam from the emission plane P along the main longitudinal projection direction for use in projecting and adjusting the entire beam by the projection optics. The output surfaces 11B and 12B forming the secondary basic light sources 51 and 52 are arranged adjacent to each other, for example, with a gap of 0.1 mm between them.

[0076] In addition, it should be noted that Figure 3 The light guides 11 and 12 shown are schematic. In reality, the first optical element is formed from a single-piece assembly obtained from a single mold, and both light guides 11 and 12 have a horn shape, such that the lateral dimensions of the input surfaces 11A and 12A are slightly smaller than the lateral dimensions of the output surfaces 11B and 12B, resulting in an equivalent clearance angle for each light guide. Therefore, the difference in lateral dimensions between the first and second light guides described above at the output surfaces of these light guides is again observed in the input surfaces of these light guides. Thus, for a high-resolution pixel having a small output surface 11B for forming a small secondary primary light source 51, corresponding to a light guide with a small input surface, light emitted by the corresponding primary primary light source 4 can pass through this small input surface.

[0077] It should be understood that the output surface 11B of the first light guide 11 corresponds to the first primary basic light source 51, and the output surface 12B of the second light guide 12 corresponds to the second primary basic light source 52.

[0078] The first optical guide 11 and the second optical guide 12 are aligned in a transverse sequence perpendicular to the longitudinal optical axis O, wherein the first subsequence A, the second subsequence B and the third subsequence C of the optical guides 11 and 12 are arranged relative to each other in the transverse direction T.

[0079] As described above, according to the present invention, the first light guide 11 is generally laterally offset relative to the longitudinal optical axis O of the projection optics 3 (i.e., the longitudinal optical axis of the optical module). This offset is established when the projection optics 3 and the first optical element 1 are positioned in the optical module 100. The first light guides 11 (here, eight) are arranged in a sequence such that the intermediate longitudinal axis O' can be defined as the center of these sequences passing through the first light guides, i.e., the junction between the fourth and fifth light guides in that sequence. Figure 3 As shown, the intermediate longitudinal axis O' is offset laterally by an offset value Δ relative to the longitudinal optical axis O, and the longitudinal optical axis O basically passes through the middle of the lateral sequence of the same row of optical guides.

[0080] More specifically, according to this embodiment, the first optical element 1 includes eight first light guides 11, which are arranged such that, when viewed from inside the vehicle, two first light guides 11 are located to the left of the longitudinal optical axis O, five first light guides 11 are located to the right of the longitudinal optical axis O, and one first light guide 11 is located at a position overlapping with the longitudinal optical axis O. As described above, it can be understood that when driving on the left, the arrangement of the first light guides will be reversed.

[0081] The projection optics 3 are arranged longitudinally at a certain distance in front of the emission plane P. The projection optics 3 are configured to project an image of a secondary primary light source along the longitudinal axis of the vehicle. This secondary primary light source is used to form a first primary beam 11' and a second primary beam 12'. The first primary beam 11' and the second primary beam 12' are oriented forward, and their combination allows segmented beams to be formed on the road scene.

[0082] Therefore, the segmented beam is formed by a first fundamental beam 11' and a second fundamental beam 12' that are continuously aligned with each other.

[0083] As in Figure 4 and Figure 5 As can be particularly seen, the specific arrangement of the light guides relative to the longitudinal optical axis relates to a specific arrangement of the fundamental beams relative to the longitudinal axis of the vehicle, which is substantially parallel to the optical axis of the optical module. In the example shown, and in the same lateral direction T defined by the arrangement of the first subsequence A, the second subsequence B, and the third subsequence C of the light guides 11 and 12, it can be observed that the segmented beams sequentially comprise a second fundamental beam 12' generated by light emitted from a second-level fundamental source 52 associated with the first subsequence A of the second light guide, a first fundamental beam 11' generated by light emitted from a first-level fundamental light source 51 associated with the second subsequence B of the first light guide, and a second fundamental beam 12' generated by light emitted from a second-level fundamental light source 52 associated with the third subsequence C of the second light guide, forming sequentially.

[0084] In this segmented beam projected onto the road by the projection optics 3, the first fundamental beam 11' is primarily laterally offset relative to the longitudinal axis of the vehicle, in a manner similar to the lateral offset of the light guide relative to the longitudinal optical axis O. In other words, most of the first fundamental beam 11' is located on one side of the longitudinal axis, and a minority of the first fundamental beam 11' is located on the other side. Figure 4As specifically shown, and due to the direct imaging of this optical module, it can be understood that the lateral offset relative to the longitudinal axis is opposite, depending on whether the light guide is generally offset to the right when viewed from inside the vehicle, or whether the corresponding fundamental beam forming part of the segmented beam projected onto the road is generally offset to the left when viewed from inside the vehicle. This lateral offset relative to the longitudinal axis is considered to be used to form a dark path with a first fundamental beam 11', which, when driving on the right, is specified to exist on the left side of the optical axis with an offset of at least 0.5°, more specifically on the order of 2° to 5°, so as not to dazzle vehicles 50 meters away.

[0085] However, the invention is not limited to the illustrated configuration, and can be provided in which the plurality of first light guides 11 and the corresponding first fundamental beams 11' are each biased to one side rather than the other relative to the longitudinal optical axis O. In other words, in this variant not shown, all the first light guides 11 are located on the same side of the longitudinal optical axis O, which, as described above, further passes through the center of the transverse sequence of light guides, and all the first fundamental beams 11' are located on the other side of the longitudinal optical axis O.

[0086] Now we will refer to more specific details Figure 4 and Figure 5 Describe the applications of this invention.

[0087] When projected onto the road scene, each secondary primary light source 51, 52 allows the projection of primary beams 11', 12', illuminating areas of the road scene. These areas slightly overlap to ensure uniform illumination. Each primary primary light source 4 is individually controlled to selectively illuminate each area of ​​the road scene. It can be understood that turning on the primary primary light source 4 produces image pixels on the secondary primary light sources 51, 52, thereby illuminating areas of the road scene, and conversely, turning off the same primary primary light source 4 produces the output surface of a dark light guide, i.e., the secondary primary light source 52 is turned off, thereby producing dark bars in the segmented beams.

[0088] Figure 4 The diagram shows the scenario where all primary light sources are switched on, and thus the scenario of high beam illumination, where the entire road scene is illuminated in front of the vehicle equipped with the optical module according to the invention. Figure 5 The illustration shows a scenario where partial beam illumination is used to avoid dazzling the driver of a motor vehicle passing through a path equipped with an optical module according to the invention. It also illustrates a scenario where partial illumination is automatically implemented once a vehicle is detected at a certain distance, and more specifically, when an oncoming vehicle is at a distance such that it is illuminated in a segment projected onto the left side of the longitudinal axis of the road scene.

[0089] This creates a dark channel in the beam to prevent glare from detected vehicles, which is achieved, in particular, by turning off a specific primary light source 4 corresponding to the position of a vehicle detected on the road. It should be noted that in Figure 5 In the case shown, from inside the vehicle, in order to generate a dark channel on the left side of the optical axis corresponding to the lateral dimensions of the three first basic beams 11', only the three first light guides 11 located on the right side of the optical axis are closed.

[0090] According to the invention, it should be noted that the dark channel is generated by shutting off the primary light source associated with the high-resolution pixel, and this is particularly advantageous because it avoids a high parasitic brightness level. Indeed, as mentioned above, the narrower the input surface of the light guide opposite to its corresponding primary light source, the greater this parasitic brightness phenomenon, because light can more easily propagate along the light guide positioned opposite to the light source. In other words, the occurrence of parasitic brightness is potentially higher for the first light guide than for the second light guide, recalling that the lateral dimension value of the first light guide is smaller than that of the second light guide. It can then be understood that the fact that the high-resolution pixel is associated with the generation or non-generation of the dark channel allows for limiting the number of high-resolution pixels that are switched on when implementing the dark channel, and thus limiting potential parasitic phenomena. Furthermore, this configuration of the invention allows for matching high-resolution pixels on each side of the dark channel and improves the quantity and quality of light near a vehicle traveling in the dark channel, thus improving illumination around the vehicle without unnecessarily risking driver glare.

[0091] When the monitoring module associated with the optical module determines that the risk of driver glare has passed, all light sources are reactivated to illuminate the entire road scene. According to a feature of the invention, it should be noted that the activation of these previously deactivated light sources corresponding to high-resolution pixels is achieved using a pulse-width modulation unit. In practice, in standard lighting operation, i.e., with all primary basic light sources 4 turned on, a requirement must be met that the maximum intensity of the projected segmented beam is centered on the longitudinal axis of the vehicle. Therefore, according to the invention, by reducing the intensity of at least some of the primary basic light sources 4 associated with these high-resolution pixels, it is possible to compensate for the overall lateral offset of the high-resolution pixels forming the first basic beam 11'. As a non-limiting example, the light intensity of these primary light sources can be reduced to 80% of their maximum intensity.

[0092] Therefore, the emission intensity of the primary primary light sources associated with the projection of the first primary beam 11' is reduced such that the light intensity emitted by them is substantially equal to the light intensity of the primary primary light source associated with the projection of the second primary beam 12'. Advantageously, this results in a larger maximum intensity spot centered on the longitudinal axis compared to the maximum intensity spot conventionally produced in the prior art. The light intensity of each primary primary light source can also be varied so that, with the maximum intensity spot centered on the vehicle's longitudinal axis, the beam intensity decreases regularly as one moves away from this central spot.

[0093] It should be noted that the optical module 100 just described can also be used to develop directional lighting functions, also known as "DBL," an abbreviation for "Dynamic Bending Light," in which the optical module 100 has light guides corresponding to the formation of "high-resolution" pixels. The advantage of this function is that it provides a beam of light to be projected towards the inside of a curve, thus providing optimal visibility for the driver. According to the invention, instead of rotating the optical module as a whole to offset its optical axis relative to the vehicle's central longitudinal axis, which corresponds to its overall direction of travel, primary light sources are selectively activated so that the projected segmented beams are deflected from the center by an adjustment offset value used to perform the DBL function, for example, between 5° and 9°. This is not a limitation of the invention. In other words, when illuminating a road scene in a straight line, several primary basic light sources are activated, forming a first combination centered on the vehicle's longitudinal axis. Primary basic light sources at the ends of the lateral sequence of these light sources are not used. And, when illuminating the road on a curve, a similar number of primary basic light sources are activated, and the activated combination is laterally offset, no longer centered on the vehicle's longitudinal axis. In the example shown, at the left-hand curve, the primary basic light source is switched on to offset the segmented beams to the left of the longitudinal axis, such that they are primarily the primary basic light sources switched on on the right side of the sequence. Of course, for vehicles traveling on the right, this would involve switching on the primary basic light sources in the opposite direction. These sequences of light guides illuminated by the primary basic light sources can then be determined to be laterally offset relative to the longitudinal optical axis, centered on the first light guide 11, according to the invention. As a result, when the DBL function is performed, the beam projected toward the inside of the curve has a center of maximum light intensity, thereby improving the driver's visibility.

[0094] Of course, the features, variations, and different embodiments of the present invention can be combined with each other in various combinations, as long as they are not incompatible or mutually exclusive. It is worth noting that variations of the present invention can be conceived that include only selected features, which are described separately from the other described features, provided that, according to the present invention, the first light guide corresponding to the high-resolution pixel is arranged in the middle of the lateral sequence of light guides so that it is generally laterally offset relative to the longitudinal optical axis of the projection optics.

Claims

1. An optical module (100) for a motor vehicle, the optical module comprising a first optical element (1) and a projection optics (3), the first optical element (1) comprising a plurality of light guides (11, 12), the projection optics (3) being arranged at a certain distance from the first optical element (1) and having a longitudinal optical axis (O). The plurality of light guides are aligned in a sequence perpendicular to the longitudinal optical axis (O) and in the transverse direction. The plurality of optical guides includes a plurality of first optical guides (11), which are arranged continuously relative to each other by being interposed between a plurality of second optical guides (12). The lateral dimension of each of the plurality of first optical guides (11) is smaller than the equivalent lateral dimension of each of the plurality of second optical guides (12). Its features are, The plurality of first light guides (11) are generally laterally offset relative to the longitudinal optical axis (O), and the plurality of first light guides (11) are associated with a primary light source (4) to project a first primary beam (11'), and the plurality of second light guides (12) are associated with a primary light source (4) to project a second primary beam (12'), and a dark channel is created by shutting down a portion of the primary light source (4) associated with the first light guides (11). The number of second light guides (12) on one side of the first light guide (11) is not equal to the number of second light guides (12) on the other side of the first light guide (11), wherein the area illuminated by the first basic beam (11') and the area illuminated by the second basic beam (12') are continuous.

2. The optical module (100) according to claim 1, characterized in that, The plurality of first optical guides (11) form a sequence arranged relative to the longitudinal optical axis, such that all of the plurality of first optical guides (11) are located on the same side of the longitudinal optical axis.

3. The optical module (100) according to any one of the preceding claims, characterized in that, The first optical element (1) sequentially includes a plurality of second optical guides (12) forming a first subsequence (A), a plurality of first optical guides (11) forming a second subsequence (B), and a plurality of second optical guides (12) forming a third subsequence (C). The first subsequence (A) has two to four second optical guides (12), the second subsequence (B) has three to eight first optical guides (11), and the third subsequence (C) has four to six second optical guides (12).

4. The optical module (100) according to any one of the preceding claims, characterized in that, The middle longitudinal axis (O') of the first optical guide (11) is laterally offset relative to the longitudinal optical axis (O) by a value of 0.5° to 5°.

5. The optical module (100) according to any one of the preceding claims, characterized in that, The first optical element (1) is made of a single block comprising the plurality of light guides, and the first optical element (1) has a common output surface (10) for light rays passing through one of the plurality of light guides or other light guides.

6. The optical module (100) according to any one of the preceding claims, characterized in that, The second optical element (2) is arranged between the first optical element (1) and the projection optical device (3).

7. The optical module (100) according to any one of the preceding claims, wherein, The projection optics (3) allows segmented beams to be projected along the longitudinal optical axis (O), the segmented beams being formed by the first fundamental beam (11') and the second fundamental beam (12'), characterized in that the first fundamental beam (11') is generally offset relative to the longitudinal optical axis (O).

8. The optical module (100) according to claim 7, wherein, The optical module includes a pulse width modulation unit configured to control at least some of the primary primary light sources (4) associated with the first light guide (11) such that the first primary beam (11') and the second primary beam (12') arranged at the center of the segmented beam have the same light intensity.

9. A motor vehicle comprising at least one headlight, the headlight comprising an optical module (100) according to any one of the preceding claims.

10. The motor vehicle according to claim 9, wherein the motor vehicle has a central longitudinal axis parallel to the direction of travel of the vehicle, characterized in that, The at least one headlight is a left headlight, and the optical module according to the invention is arranged such that the plurality of first light guides (11) are generally located between the longitudinal optical axis (O) and the intermediate longitudinal axis of the vehicle.

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