Mask for image position correction of virtual image

Abstract

The present invention relates to a shield for correcting the image position of a virtual image (5) that can be projected onto a windshield (3) of a vehicle by means of a head-up display (2). A first positioning mark (7), a second positioning mark (8) and a calibration mark (9) are provided on a plate (6) of the shield (1). The plate is transparent at least in the area of ​​the first positioning mark, the second positioning mark and the calibration mark, so that a first image (33), a second image (36) and a calibration image (47) can be obtained. The first image contains the first positioning mark and a first positioning pattern (34) output on the vehicle side, which is photographed directly through the plate. The second image contains the second positioning mark and a second positioning pattern (37) output on the vehicle side, which is reflected by a mirror (10) of the shield and photographed through the plate. The calibration image contains the calibration mark and a calibration pattern (48) projected onto the windshield by means of the head-up display and photographed directly through the plate.

Description

Technical Field

[0001] The invention relates to a mask for correcting the image position of a virtual image that can be projected onto the windshield of a vehicle by means of a head-up display. The invention also relates to a corresponding calibration component and a corresponding method. Background Art

[0002] So-called head-up displays are used more and more frequently in modern vehicles. Head-up displays are used to project information onto the windshield of the vehicle and thus into the driver's field of vision. As a result, the driver perceives that the projected image is embedded in a part of the vehicle environment that can be seen through the windshield, thereby realizing so-called augmented reality ("augmented reality" in English). In addition to projecting static information, that is, information that is always located at the same position on the windshield, information whose position changes can also be shown on the windshield. Examples of this can be navigation arrows positioned on the road or lines for indicating a safe distance to be maintained, highlighting of traffic signs, marking of potential sources of danger (such as pedestrians), etc. Such a head-up display is disclosed, for example, in patent application DE 10 2010 013 224 A1.

[0003] In the context of augmented reality that can be generated with the aid of a head-up display, it is very important that the projection image is projected at the correct position on the windshield. Otherwise, for example, it may happen that the hazard positions etc. marked with the aid of the head-up display from the driver's perspective do not match the corresponding positions in the vehicle surroundings. Therefore, it is necessary, in particular before starting the head-up display or the corresponding vehicle or after an accident etc., to carry out an image position correction or image position calibration.

[0004] In order to carry out image position correction or image position calibration, a sunshade with an aperture or a peephole is usually first fixed to the sun visor support of the motor vehicle in a pivotable manner. In addition, an adjustment slide with a calibration plate is positioned in front of the motor vehicle at a fixed preset relative position relative to the vehicle. Subsequently, a test image is projected onto the windshield of the motor vehicle with the help of a head-up display, which test image corresponds to the calibration pattern shown on the calibration plate. Now, the calibrator observes the calibration plate through the aperture of the sunshade and determines the possible position deviation between the calibration pattern of the calibration plate and the projected test image. Subsequently, by correspondingly changing the calibration parameters associated with the head-up display, calibration is carried out in the following manner, namely: the position of the test image on the windshield is changed in such a way that the test image coincides with the calibration pattern of the calibration plate. Here, the sunshade with an aperture guarantees the correct viewing position of the calibrator during the calibration process or the viewing position required for correct calibration, which viewing position essentially corresponds to the expected driver's line of sight position. Inaccuracies due to the pivotability of the shutter have only a negligible effect on the calibration, since the calibration plate used is located outside the vehicle and the optical path lengths involved are therefore large enough that changes or pivotability of the shutter have no significant effect on it. The calibration is successfully concluded when there is no longer any misalignment between the projected test image and the pattern shown on the calibration plate.

[0005] For example, a corresponding calibration concept is known from patent application DE 10 2015 008 887 A1, in which, instead of using a mask, a measuring unit is brought to the assumed position of the driver's head by means of a robot, which acquires an image projected by means of a head-up display and an image of a calibration plate. In this case, the position of the measuring unit is acquired by a camera using markings provided on the measuring unit.

[0006] Another approach for correcting a head-up display is known from patent application DE 10 2014 224 302 A1. In this approach, the vehicle is moved by means of a frame, wherein a vision camera attached to a manipulator acquires data that is projected onto the windshield. Based on the images acquired in this way, the image generated by means of the head-up display is corrected.

[0007] A disadvantage associated with known calibration concepts is that they are very complex and expensive in terms of the technical components they require, such as a separate calibration plate located outside the vehicle, which must be in a precisely predetermined relative position relative to the vehicle. Summary of the invention

[0008] The object of the present invention is to provide a relatively simplified concept for correcting the position of an image in a head-up display.

[0009] According to the invention, in a shield of the type mentioned at the outset, this object is achieved in that a first positioning mark, a second positioning mark and a calibration mark are provided on the plate of the shield, wherein the plate is transparent at least in the region of the first positioning mark, the second positioning mark and the calibration mark, so that

[0010] a first image, which contains the first positioning mark and a first positioning pattern which is recorded directly through the sheet and output on the vehicle side,

[0011] a second image, which contains a second positioning mark and a second positioning pattern output on the vehicle side, which is reflected by the mirror of the shutter and photographed through the plate, and

[0012] A calibration image comprising calibration marks and a calibration pattern which is projected onto the windshield by means of a head-up display and recorded directly through the pane.

[0013] The invention is based on the idea that the aspects required for calibration, such as the provision of a calibration pattern and means for correctly positioning the involved components, are implemented by means of a shield. Thus, other components that would otherwise be required, such as a separate calibration plate that must be positioned outside the motor vehicle, are not required.

[0014] The shield is therefore suitable for capturing a calibration image, which shows the calibration mark of the shield and the image of the head-up display projected onto the windshield. The image projected onto the windshield is captured through the plate of the shield. In other words, the plate is located in the visible field of the calibration image in such a way that if the plate is not transparent in this area, the projected image is covered by the plate. Finally, calibration is performed in the following way, that is, using the position deviation or misalignment between the calibration pattern and the calibration mark on the calibration image to determine the correction value, wherein the calibration is performed by adjusting the calibration parameters related to the head-up display or matching or adjusting the correction value. Here, the calibration mark is not provided by an externally arranged adjustment slide with a calibration plate as in the prior art, but by a corresponding mark applied to the shield.

[0015] In order to correctly determine the correction value, it is necessary that when the calibration image is recorded, the shutter is located in a final shutter position that is fixedly preset and defined relative to the vehicle, and that the calibration image is recorded from the perspective of a final detection position that is also fixedly preset and defined relative to the vehicle. Therefore, the information to be acquired with the aid of the calibration image for determining the correction value can be related to the corresponding shutter position and detection position, and the correct shutter position also plays an important role compared to the prior art, because the involved optical path length is significantly shorter than in the prior art.

[0016] Therefore, in order to correctly position the shutter and the detection position, a first positioning mark and a second positioning mark of the shutter are set. When the first positioning mark coincides with the first positioning pattern on the first image and the second positioning mark coincides with the second positioning pattern on the second image, the shutter and the image acquisition device (such as a camera or a person's eye) are located in their respective correct positions when acquiring the calibration image. Therefore, the first positioning mark and the second positioning mark are arranged on the plate of the shutter so that if the first positioning pattern and the second positioning pattern are arranged in corresponding fixed and known positions in the motor vehicle, the corresponding overlap only exists when the shutter and the image acquisition device are both in their correct positions. This situation allows the required final shutter position and final detection position to be determined and occupied relatively simply and without great expense with the help of the first image and the second image.

[0017] With regard to the first image, provision can be made that the first positioning pattern is recorded directly through the transparent sheet, just as the calibration pattern during the calibration process. However, the first image alone is not sufficient to determine the positions of the mask and the observer or the camera required for acquiring the calibration image. Therefore, due to the uncertainty of the system, there are a plurality of possible positions that can be occupied by the mask and the image acquisition device, so that an overlap of the first positioning pattern and the first positioning mark occurs in the first image.

[0018] In order to finally determine the final detection position and the final shutter position, a second image is acquired, wherein it is important in this respect that the second positioning pattern photographed through the plate is not photographed directly, but rather is photographed in a manner reflected by a mirror of the shutter. In other words, the second image does not directly show the second positioning pattern, but rather shows a corresponding mirror image of the second positioning pattern. By photographing the second positioning pattern not directly but via a mirror when acquiring the second image, the optical path with respect to the second positioning pattern is correspondingly extended, thereby making it possible to determine the detection position and the shutter position with sufficient accuracy. In addition, by taking into account both images, the final detection position and the final shutter position can be clearly determined, which cannot be achieved based on only one image.

[0019] Regarding the specific design of the shield, it should be noted that the shield is typically arranged inside a motor vehicle when image position correction is performed and therefore has corresponding dimensions suitable for this. In particular, the plate of the shield is essentially rectangular, for example with rounded corners to avoid sharp edges that could injure the calibrator or scratch the interior device components of the vehicle. The plate can be designed to be flat. Alternatively, the plate can have a curved shape, wherein the corresponding shape can be matched to the likewise curved shape of the windshield of the vehicle.

[0020] In order to be able to record the first and second positioning patterns and the calibration pattern through the plate, the plate is transparent in the corresponding areas, i.e. in the area of ​​the respective corresponding markings. Likewise, the entire plate can be transparent. In this case, "transparent" means that the light used to record the first and second images and the calibration image, in particular light in the optical wavelength range, passes through the plate undisturbed, preferably completely undisturbed.

[0021] In a preferred embodiment, the visor can be fastened movably in the vehicle. Thus, it is not necessary to hold the visor in its position in a relatively complicated manner, for example by means of a robot which is introduced from the outside through the side window into the vehicle. In this context, it is particularly preferably provided that the plate can be fastened pivotably in the vehicle. Thus, pivotable fastening can be realized technically relatively simply, for example by means of a sun visor holder of the vehicle. Thus, the plate can have a fastening means which matches the sun visor holder, for example a suspension eye if the sun visor holder is a hook-shaped holder.

[0022] Since two sun visor holders are often provided in vehicles, namely one each on the driver's side and the passenger's side, the sun visor preferably has two corresponding fastening elements. The sun visor can thus be pivoted, in particular, about a single axis extending parallel to the horizontal vehicle transverse axis. As a result, the sun visor only has one degree of freedom of movement in the fixed state, which ultimately simplifies the determination and adjustment of the sun visor position.

[0023] In the shield according to the invention, it is particularly preferably provided that the mirror is arranged or can be arranged laterally on the plate. Although a large design margin is given with regard to the position of the mirror on the plate, a corresponding lateral arrangement leads to a particularly large extension of the optical path in relation to the second positioning pattern on the second image. Since the correct relative position between the mirror and the second positioning mark is extremely important for an accurate calibration, the mirror is particularly preferably arranged fixedly on the plate so that this relative position does not change even in the event of a collision or the like. In this respect, the connection can be provided, for example, by means of an adhesive or a screw connection or the like.

[0024] The mirror is arranged in particular at an angle, for example of about 90°, relative to the plate. With respect to the detection position, the mirror is arranged either in front of the plate or behind the plate. In the first case, the light showing the second positioning pattern first passes through the plate and is then reflected at the mirror, while in the second case the situation is exactly the opposite.

[0025] With regard to the mirrors, it can be provided that a left-side mirror is or can be arranged on the left side of the plate, and a right-side mirror is or can be arranged on the right side of the plate. If mirrors are arranged on both sides of the plate, in particular a symmetrical plate can be used in left-hand drive and right-hand drive vehicles. Accordingly, it can also be provided that the first positioning mark, the second positioning mark and the calibration mark are each arranged doubly, more precisely symmetrically, on the plate.

[0026] At least in the region of the first positioning mark, the second positioning mark and the calibration mark, the plate can be made of a transparent plastic, in particular plexiglass. Therefore, the corresponding transparent plastic typically has favorable properties with regard to the lowest possible weight of the plate, with regard to mechanical properties, in particular with regard to breaking strength and fragmentation strength, and with regard to transparency properties. Particularly preferably, the plate is made entirely of a transparent plastic.

[0027] Preferably, the first positioning mark and / or the second positioning mark and / or the calibration mark is or comprises at least one line and / or at least one cross and / or at least one rectangle, in particular a square and / or at least one circle. It is conceivable that the corresponding mark or pattern comprises a combination of a plurality of corresponding geometric shapes and contours, thereby simplifying the determination of the misalignment on the corresponding image. Thus, for example, the rectangles or squares used to realize the corresponding mark or the corresponding pattern can form a checkerboard or chessboard shape.

[0028] In terms of the preset patterns and marks, what is required for successful calibration is to find an overlap or misalignment on the acquired image. It is therefore important that the mark-pattern pairs that are respectively set are designed so that in principle a corresponding overlap or misalignment can be found. For example, this is the case when the mark and the pattern are identical in terms of their geometric shapes. However, in general, it is sufficient for the corresponding shapes to at least match each other accordingly in order to find a misalignment. For example, the mark can be a circle with a diameter, and the associated pattern can be a ring whose inner diameter is substantially equal to the diameter of the circle of the mark. It should be noted here that the shapes must match each other mirror-symmetrically, because the second image contains a mirror image of the second positioning pattern. Therefore, an axisymmetric geometry can be set in terms of the second positioning pattern and the second positioning mark.

[0029] Mark for example can be respectively arranged as the stickable label that is installed on the plate.Alternatively, mark can be printed, embossed (especially hot embossing), punched or laser cut on or in the plate, especially on or in the organic glass.

[0030] Furthermore, the invention relates to a calibration assembly for image position correction of a virtual image which can be projected onto a windshield of a vehicle by means of a head-up display. According to the invention, the calibration assembly comprises:

[0031] - a shutter according to the above description,

[0032] a first display device located on the vehicle side for outputting a first positioning pattern,

[0033] - a second display device located on the vehicle side for outputting a second positioning pattern, and

[0034] -Head-up display on the vehicle side.

[0035] All features, advantages and aspects explained in conjunction with the shield according to the invention are likewise transferable to the calibration assembly according to the invention and vice versa.

[0036] As already explained above, for the image position correction, it is therefore necessary to output the first positioning pattern and the second positioning pattern at known and fixedly predefined positions relative to the motor vehicle, which is ensured by two display devices. The display devices can be arranged fixedly or releasably fastened in the motor vehicle at fixedly predefined and defined positions.

[0037] With regard to the head-up display on the vehicle side, it can be provided that the head-up display comprises an imaging unit for generating a projection and an optical module for influencing the projection light generated by means of the imaging unit, in particular deflecting or shifting the projection light, the optical module in particular having a collimator. The corresponding influencing can be achieved by means of a system of reflectors and / or lenses of the optical module. The imaging unit emits the projection light in the direction of the projection surface, in this case in the direction of the windshield of the vehicle.

[0038] The windshield is a mapped / reflective and light-transmitting glass, so that in addition to the mapped information of the head-up display, the driver can also see the real environment behind the glass. The imaging unit, that is, the projector and the optical module are arranged behind the dashboard of the vehicle from the driver's perspective, wherein the projection light is emitted upward toward the windshield.

[0039] Here, the specific implementation or calibration of the image position correction particularly relates to the optical module and the deflection of the projected image caused by the optical module. Therefore, the calibration parameter related to the head-up display that is adjusted for the image position calibration can be the degree or size of the deflection of the projection light in a certain direction (for example, the optical axis of the imaging unit, which in the installed state of the head-up display can correspond to the vertical axis of the vehicle, for example). Therefore, in this regard, two calibration parameters can be adjusted. The first calibration parameter can relate to the degree or size of the deflection of the projection light in terms of swinging around the transverse axis of the vehicle. Therefore, the first calibration parameter relates to the movement of the image projected on the windshield in the up-down direction. The second calibration parameter can relate to the degree or size of the deflection of the projection light in terms of swinging around the longitudinal axis of the vehicle. Therefore, the second calibration parameter relates to the movement of the image projected on the windshield in the left-right direction.

[0040] The first display device can be a first display arranged on the dashboard of the vehicle on the driver's side, and / or the second display device can be a second display arranged centrally on the dashboard or a dashboard or a center console of the vehicle. Thus, the first and / or second display device is not only used to implement the image position correction, but can also be used for other purposes within the scope of daily use of the vehicle. For example, the first display device or the first display can be a speedometer. The second display device can be part of the vehicle's infotainment system.

[0041] The calibration assembly may include a camera, by means of which the first image and / or the second image and / or the calibration image can be acquired. It is also conceivable in conjunction with the invention that, for acquiring the images, the calibrator sits in the driver's seat of the vehicle and carries out the acquisition of the images and the associated evaluation and calibration himself.

[0042] If a camera is provided, the camera can be arranged on a positioning device, in particular on a robot which is guided from the outside through the side window of the vehicle, wherein the position of the camera can be changed by means of the positioning device. Thus, the camera can be moved into the corresponding position, for example the final test position, automatically by means of the electromechanical actuators of the positioning device and therefore in particular with greater precision and accuracy than if the calibrator acquired the corresponding images himself.

[0043] In the calibration arrangement according to the invention, it can be provided that the calibration arrangement comprises at least one control device which is designed to evaluate the first image and / or the second image and / or the calibration image and / or to generate control signals for actuating the positioning device or a positioning device and / or to generate control signals for image position correction, in particular for actuating an optical module of a head-up display. The image can therefore preferably be evaluated with the aid of software, by means of which the misalignment or position deviation between the corresponding pattern and the marking on the image can be determined. The details of such software programs are sufficiently known to a person skilled in the art and therefore will not be explained in detail within the scope of this description.

[0044] Based on the position deviation or the variable determined therefrom, a control signal can be generated by means of the control device, which causes the position of the camera and, if applicable, the shutter to be changed by means of the positioning device and causes the adjustment of calibration parameters. For example, the variable can be determined based on at least one lookup table stored in the control device or calculated based on at least one predefined analytical relationship.

[0045] Furthermore, the invention relates to a method for correcting the image position of a virtual image which can be projected onto a window pane of a vehicle by means of a head-up display, wherein the method comprises the following calibration preparation steps:

[0046] a) arranging a shutter according to the above description in a temporary shutter position in a vehicle,

[0047] b) acquiring a first image from the perspective of at least one temporary detection position,

[0048] c) acquiring a second image from the perspective of the temporary detection position,

[0049] d) determining first misalignment information, the first misalignment information being related to a possible position deviation between the first positioning pattern and the first positioning mark in the first image,

[0050] e) determining second misalignment information, which is related to a possible position deviation between the second positioning pattern and the second positioning mark in the second image,

[0051] f) determining a detection position deviation and a shutter position deviation according to the first misalignment information and / or the second misalignment information, the detection position deviation describing a deviation between a temporary detection position and a final detection position, and the shutter position deviation describing a deviation between a temporary shutter position and a final shutter position, and

[0052] g) changing the temporary detection position to the final detection position or another temporary detection position, and changing the temporary shutter position to the final shutter position or another temporary shutter position according to the detection position deviation and / or the shutter position deviation,

[0053] In order to correct the image position, the following steps are performed:

[0054] h) acquiring a calibration image from the perspective of the final detection position when the shutter is arranged in the final shutter position,

[0055] i) determining calibration misalignment information which is related to a possible position deviation between the calibration pattern and the calibration mark on the calibration image,

[0056] j) determining at least one correction value based on the calibration misalignment information, the correction value describing a parameter adaptation / parameter adjustment required for image position correction, wherein the correction value can be determined based on the fact that the calibration image has been acquired from the perspective of the final detection position and the shutter is now arranged in the final shutter position, and

[0057] k) Correcting the image position by changing at least one calibration parameter associated with the head-up display by a correction value.

[0058] All features, advantages and aspects explained in conjunction with the method according to the invention are likewise transferable to the shield according to the invention and the calibration assembly according to the invention, and vice versa.

[0059] As has already been mentioned several times, for the image position correction, it is absolutely necessary that here, in addition to the first and second display devices, the shutter and the image acquisition means (e.g. a camera or the eye of the calibrator) are also arranged in a predefined and fixedly defined final position, since otherwise it would not be possible to determine the correction value from the position deviation between the calibration pattern and the calibration mark on the calibration image and thus to perform the image position correction. The method steps carried out within the scope of the calibration preparation step therefore have the purpose of determining and assuming the required final shutter position and final detection position.

[0060] Therefore, in step a), it is provided that the visor according to the invention described above is arranged in a temporary visor position in the vehicle, in particular by hanging the visor in the sun visor bracket of the vehicle, so that the visor can finally swing around the horizontal axis defined by the sun visor bracket and is therefore movable in one degree of freedom. The temporary visor position can be any position in terms of the swivellability of the visor. With respect to the temporary detection position to be occupied in steps b) and c), which is, for example, the head position or eye position of the calibrator or the camera position, there are three degrees of freedom, i.e., degrees of freedom in three spatial directions. With respect to the temporary position, the temporary position should be selected so that the temporary detection position is located, for example, at the predicted eye position of the vehicle driver, and the second positioning pattern in the mirror can actually be seen in the second image. For example, the image acquisition in steps b) and c) can be carried out in the range of the image being manually viewed from the calibrator or in the range of the image acquisition and storage performed from the camera side.

[0061] With regard to steps d) and e), the first image and the second image are evaluated by acquiring a measure or degree of positional difference between the locating mark and the locating pattern on the respective image plane, i.e. misalignment information. The misalignment information may respectively include a possible horizontal position deviation and a possible vertical position deviation between the respective locating pattern and the associated locating mark on the respective image.

[0062] Finally, the purpose of acquiring the misalignment information is to determine information about the deviations of the current, i.e. provisional, detection position and shutter position from the respective final position. Subsequently, the information, i.e. the detection position deviation and the shutter position deviation, is determined in step f) of the method. As already explained, for this purpose, corresponding lookup tables or predefined analytical relationships can be used.

[0063] Then, in step g) of the method, the detected position and the shutter swing position are corrected, that is, based on the detected position deviation and the shutter position deviation just determined.

[0064] With regard to steps a) to f) of the method, these steps can be performed sequentially according to the alphabetical order of these steps. Alternatively, it can also be provided that after step b), i.e. after acquiring the first image, step d), i.e. determining the first misalignment information, is directly performed, followed by steps f) and g), i.e. matching the respective positions for the first time. This ultimately corresponds to the first coarse positioning in terms of the shutter position and the detection position. Next, step c), i.e. acquiring the second image and step e), i.e. determining the second misalignment information, can be performed, and then steps f) and g) can be repeated, so that this part ultimately corresponds to the fine adjustment of the respective positions. Alternatively, the acquisition of the second image and, if necessary, the subsequent determination of the second misalignment information can also be performed before the acquisition of the first image. In other words, steps c), e), f) and g) associated with the second image can be performed during the first coarse positioning, and then steps b), d), f) and g) associated with the first image are performed for fine positioning.

[0065] Regardless of the specific sequence of steps a) to g), it is necessary in each case that the final detection position and the final shutter position are assumed after the last execution of step g) and with the highest possible accuracy. If this is the case, the actual image position correction begins in steps h) to k).

[0066] After the calibration image has been acquired in step h) of the method (i.e., also acquired, for example, from the corrector himself or from the camera), the calibration misalignment information is determined in step i), i.e., similarly to the determination of the first and second misalignment information in the calibration preparation process. Thus, calibration misalignment information related to the horizontal and vertical deviations between the calibration pattern and the calibration mark on the calibration image can be acquired.

[0067] Next, in step j), information related to the calibration parameter matching required for image position correction, ie, correction values, is determined from the calibration offset information. This can be done based on a suitable lookup table or a predefined analytical relationship.

[0068] Finally, in the last step k) of the method, the actual calibration is carried out, ie the calibration parameters are specifically changed by the correction value, with the end of which the method and the calibration implementation process are essentially ended.

[0069] With regard to the calibration preparation, i.e. steps a) to g), it can be provided that after step g) of the method, the calibration conditions are checked and, if they are met, the method is continued in step h), and if they are not met, the method is restarted in step a). In this case, the calibration conditions are met when the detected detection position deviations and shutter position deviations are less than the respective preset limit values. In other words, the check of the calibration conditions after step g) may lead to a repetitive traversal of steps a) to g), more precisely until the current detection position and shutter position are sufficiently close to the desired final detection position and final shutter position. For this purpose, the greater the preset limit values, the greater the tolerances.

[0070] Analogously to the calibration condition after step g), an end condition can be checked after step k) of the method, wherein the method is terminated if the end condition is met and continued again in step h) if it is not met. In this case, the end condition is met in particular when the correction value determined in step j) is less than a corresponding predefined limit value. Thus, the actual calibration process is also run through repeatedly here, to be precise until the calibration pattern on the calibration image coincides with the calibration mark with sufficient accuracy, which is specified according to the corresponding predefined limit values. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Further details and advantages are obtained from the following exemplary embodiments and with reference to the accompanying drawings.

[0072] Figure 1 Schematically shows an embodiment of a shutter according to the present invention,

[0073] Figure 2 Schematically shows a vehicle including Figure 1 A first embodiment of a calibration assembly of a shutter,

[0074] Figure 3 Schematically shows a vehicle including Figure 1 A second embodiment of a calibration assembly of a shutter,

[0075] Figure 4 Schematically shows the perspective of the interior space of the vehicle. Figure 2 or Figure 3 A view of a portion of the calibration assembly,

[0076] Figure 5 Schematically shows the reference Figure 2 A first embodiment of the method according to the invention of a calibration assembly,

[0077] Figure 6 Schematically showing an example of a first image,

[0078] Figure 7schematically shows an example of a second image,

[0079] Figure 8 schematically shows an example of a calibration image, and

[0080] Fig. 9 Schematically shows the reference Figure 3 A second embodiment of the method according to the invention of a calibration assembly. DETAILED DESCRIPTION

[0081] Figure 1 The shield 1 according to the invention is shown, by means of which a projection via a head-up display 2 onto a vehicle 4 (for example on a Figure 2 and Figure 3 The image position of a virtual image 5 on a windshield 3 of a motor vehicle (shown in FIG. 4 ) is corrected. The shield 1 comprises, for example, a flat plate 6, which is made of a transparent plastic, i.e., plexiglass. A first positioning mark 7, a second positioning mark 8, and a calibration mark 9 are provided on the plate 6. In addition, the shield 1 also comprises a mirror 10 arranged on the side of the plate 6. The mirror 10 is glued to the edge of the plate in a manner that it extends backward from the plate 6 at a right angle. In order to fix the shield 1 in the vehicle 4, the shield 1 has two fixing parts 11 in the form of hanging holes on the upper side, by means of which the shield can be fixed to a hook-shaped sun visor bracket 12 of the vehicle 4. Therefore, the shield 1 can be swung about a swivel axis 13 defined by the fixing parts 11 or the sun visor bracket 12.

[0082] from Figure 1 It can be seen that the shield 1 or the plate 6 has a symmetrical shape about its vertical axis. The vehicle 4 for which the shield 1 is shown is a left-hand drive vehicle. Additionally or alternatively, the markings 7, 8, 9 and the mirror 10 can also be arranged to be mirrored inversely about the axis of symmetry, so that the shield 1 can also be used for right-hand drive vehicles.

[0083] The details of the markings 7, 8, 9 are explained below. These markings are provided as adhesive labels on the plate 6 by way of example. Alternatively, these markings 7, 8, 9 can also be printed, embossed or laser cut on the plate.

[0084] The first positioning mark 7 includes three Figure 1 The lines shown are arranged one above the other and side by side. The second positioning mark 8 comprises a plurality of squares arranged in a chessboard shape. The calibration mark 9 comprises a cross and four squares evenly arranged around the cross. The specific design of the marks 7, 8, 9 is to be understood as exemplary only. Other shapes (especially circles, etc.) and arrangements of these shapes are also possible.

[0085] Figure 2A first embodiment of a calibration assembly 14 according to the invention is shown, which comprises a visor 1 and a first display device 15, a second display device 16 and a head-up display 2 of a vehicle 4. The first display device 15 is a first display 17 arranged on the driver's side on a dashboard 19 of the vehicle 4, which is used as a speedometer or a corresponding instrument cluster in daily driving operation. The second display device 16 is a second display 18 arranged on a center console 20 of the vehicle 4, which is used as part of an infotainment system of the motor vehicle 4 in daily driving operation.

[0086] Next, details about the head-up display 2 arranged behind the instrument panel 19 are explained. Figure 2 The head-up display 2 includes an imaging unit configured as a projector 21 for generating a projection in order to generate a virtual image 5. In addition, the head-up display 2 also includes an optical module 22, by means of which the emission direction of the projection generated by the projector 21 can be influenced, or more precisely, the emission direction can be deflected. This is achieved by means of a system of reflectors and / or lenses of the optical module 22. In order to generate the virtual image 5, a projection is emitted upward in the direction of the windshield 3 by means of the projector 21. Here, the projection is reflected on the windshield 3 in the direction of the driver of the motor vehicle 4, so that from this perspective, on the one hand, the virtual image 5 can be seen on the windshield 3, and on the other hand, since the windshield 3 is transparent, the environment in front of the motor vehicle 4 can be seen.

[0087] In order to implement the method for image position correction according to the present invention, Figure 2 In the case of the calibration arrangement 14 shown, a calibrator 24 is provided, sitting on a driver's seat 23 of the vehicle 4. Details relating to this will be explained later in conjunction with corresponding exemplary embodiments of the method according to the invention.

[0088] Figure 3 A second embodiment of a calibration assembly 14 according to the invention is shown, which is similar to the calibration assembly 14 only insofar as it is relevant to the calibrator 24. Figure 2 The calibration assembly 14 shown is different. Figure 3 In the illustrated calibration assembly 14, a camera 25 is provided instead of a calibrator 24. The camera 25 is carried by a positioning device 26, i.e. a manipulator 27, which passes from the outside through the side window of the vehicle 4. The position of the camera 25 can be changed by means of the positioning device 26. The details of the corresponding position change will be explained in detail later in conjunction with the corresponding embodiment of the method according to the invention. The positioning device 26 is controlled by control signals of a control device 28, which in the case of a corresponding control and evaluation system not shown in detail here is located outside the vehicle 4.

[0089] To better explain the Figure 2 and Figure 3 The calibration assembly 14 shown in FIG. Figure 4 4 shows the calibration arrangement from a perspective looking forward in the longitudinal direction of the vehicle from the interior of the vehicle 4 , but does not show the calibrator 24 or the camera 25 .

[0090] Next, refer to Figure 5 A first exemplary embodiment of a method according to the invention for image position correction of a virtual image 5 which can be projected onto a windshield 3 of a vehicle 4 by means of a head-up display 2 is described. To implement this exemplary embodiment, the assistance of a calibrator 24 is required, wherein the exemplary embodiment involves Figure 2 The calibration components are shown in FIG.

[0091] In principle, the method can be divided into two phases, namely a preparation phase 29 and a calibration phase 30. The preparation phase 29 is used to place the shield 1 and the eye of the calibrator 24 in the final shield position and final test position respectively required for the actual calibration that subsequently takes place during the calibration phase 30.

[0092] Therefore, in a first step 31 of the method, the visor is arranged in a temporary visor position in the vehicle 4. For this purpose, the visor 1 is suspended on a visor support 12 by means of a fastening element 11, wherein the visor 1 can be pivoted about a pivot axis 13 extending parallel to the transverse axis of the vehicle 4. In this case, the temporary visor position is any pivot position of the visor 1.

[0093] In a second step 32 of the method, a first image 33 is acquired from the perspective of the temporary detection position. The first image 33 is acquired by a calibrator 24 who is seated in the driver's seat 23 and whose head or eyes are now in the temporary detection position. The temporary detection position is any possible head position of the driver of the vehicle 4. The first image 33 is acquired in the direction of the first positioning mark 7. Figure 6 An example of what the first image 33 may look like is shown in . Thus, the first image 33 shows the first positioning mark 7 and the first positioning pattern 34 which is recorded directly through the sheet 6 of the mask 1. The first positioning pattern 34 corresponds to the first positioning mark 7 in its shape.

[0094] After the acquisition of the first image 33, in a next step 35, a second image 36 is acquired from the perspective of the temporary detection position by the calibrator 24. Here, the second image 36 is acquired in the direction of the second positioning mark 8, so that, for example, Figure 7The second image 36 shown in FIG. 1 contains the second positioning mark 8 and the second positioning pattern 37 output by means of the second display device 16. However, unlike the first positioning pattern 34, the second image 36 does not contain the second positioning pattern 37 which is directly recorded through the plate 6, but the second positioning pattern 37 is now additionally reflected by the mirror 10 of the shutter. In other words, in addition to the second positioning mark 8, the second image 36 also contains the mirror 10, in which the second positioning pattern 37 of the second display device 16 can be seen, wherein the mirror image is correspondingly captured through the plate 6. The geometry of the mirror-symmetrical second positioning pattern 37 corresponds to the second positioning mark 8.

[0095] In the next step 38 of the method, first misalignment information is determined from the first image 33. The first misalignment information describes the extent or size of a possible horizontal position deviation 29 and a possible vertical position deviation 40 between the first positioning pattern 34 on the first image 33 and the first positioning mark 7.

[0096] Similarly, in the next step 41 of the method, second misalignment information, ie information about the extent or size of a possible horizontal position deviation 42 and a possible vertical position deviation 43 between the second positioning pattern 37 on the second image 36 and the second positioning mark 8, is determined.

[0097] In the next step 44 of the method, the detection position deviation and the shutter position deviation are determined. The detection position deviation describes the deviation between the temporary detection position, i.e. the current detection position, and the final detection position to be determined. Similarly, the shutter position deviation describes the deviation between the temporary shutter position, i.e. the current shutter position, and the final shutter position to be determined.

[0098] These deviations are determined based on the first misalignment information and the second misalignment information, i.e., the deviations between the patterns 34, 37 and the markings 7, 8 on the images 33, 36. Here, a larger deviation between the patterns 34, 37 and the markings 7, 8 means that there is a correspondingly larger deviation between the current detection position and / or the shutter position and the final detection position and the final shutter position. Therefore, when the positioning patterns 34, 37 coincide with the corresponding markings 7, 8 of the plate 6 on the first image 33 and the second image 36, the calibrator 24 is exactly in the final detection position and the shutter 1 is exactly in the final shutter position.

[0099] In the next step 45 of the method, the calibrator 24 changes the temporary detection position to the final detection position and changes the temporary shutter position to the final shutter position.

[0100] Figuratively speaking, the calibrator 24 makes the positioning marks 7, 8 on the images 33, 36 coincide with the positioning patterns 34, 37 by means of constantly or repeatedly matching the detection position and the shutter position in the method steps described above, which can eventually be performed simultaneously, and finally reaches the final detection position and makes the shutter 1 reach the final shutter position. Here, it can also be provided that the calibrator 24 uses the second image 36 to roughly locate the temporary shutter position and the temporary detection position, more precisely in the following way: the calibrator searches for a temporary position combination under which the calibration pattern 37 in the mirror 10 appears in the second image 36. Then, the calibrator can use the first image 33 for precise positioning. All the method steps described so far are related to the preparation stage 29 mentioned at the beginning.

[0101] Since there is only one possibility for the detection position and the shutter position, in which there is no positional deviation on the images 33, 36 or the two positioning marks 7, 8 coincide with the respectively associated positioning patterns 34, 37, namely the final detection position and the final shutter position, once the respective final positions have been reached, the method is continued in the next step 46 which starts the calibration phase 30. In step 46, the calibrator 24 acquires a calibration image 47 which, for example, looks like Figure 8 4. The acquisition is performed from the perspective of the final detection position, wherein the shutter 1 is in the final shutter position. The calibration image 47 shows the calibration marks 9 of the plate 6 and the calibration pattern 48 projected onto the windshield 3 by means of the head-up display 2 and recorded directly through the plate 6.

[0102] In the next step 49 of the method, the calibrator 24 determines calibration misalignment information, which relates to the degree or size of a possible positional deviation between the calibration pattern 48 on the calibration image 47 and the calibration mark 9. Specifically, the horizontal positional deviation 50 and the vertical positional deviation 51 between the calibration pattern 48 and the calibration mark 9 on the calibration image 47 are determined.

[0103] In the next step 52 of the method, correction values ​​are determined from the calibration misalignment information, i.e. the position deviations 50 and 51, which describe the parameter adjustments required for the image position correction. In other words, the required degree or magnitude by which the projection generated by means of the head-up display must be deflected by the optical module 22 is determined from the position deviations 50, 51 in order to display the virtual image 5 in the correct position on the windshield 3. It also applies here that the greater the position deviations 50, 51, the greater the required change in the calibration parameters associated with the head-up display 2 must be for the image position correction.

[0104] Now, in the last step 53 of the method, the image position correction is performed by adjusting or changing the calibration parameters. Specifically, the first calibration parameter and the second calibration parameter, i.e., the magnitude or intensity of the deflection of the projection in the first direction perpendicular to the projection's exit direction by means of the optical module 22, and the magnitude or intensity of the deflection of the projection in the second direction perpendicular to the projection's exit direction and the first direction by means of the optical module 22, can be adjusted accordingly. Here, the first direction or the first calibration parameter corresponds to the horizontal position deviation 50, and the second direction or the second calibration parameter corresponds to the vertical position deviation 51. The calibration parameters are also adjusted accordingly by the calibrator 24, for example, via one of the displays 17, 18.

[0105] The steps of the calibration phase 30 can also be performed almost simultaneously by the calibrator 24 , wherein the calibrator 24 continuously adjusts calibration parameters associated with the head-up display 2 and in this case pays attention to deviations between the calibration pattern 48 and the calibration mark 9 on the calibration image 47 .

[0106] Finally, the method ends once the calibration pattern 48 and the calibration mark 9 are completely consistent on the calibration image 47. It is important that not only the shutter 1 is stably held in the final shutter position, but also the calibrator 24 or his eyes are stably held in the final detection position during the entire calibration phase 30. In order to control this, the calibrator 24 should not only focus on the calibration image 37 during the calibration phase 30, but also on the first image 33 and the second image 36.

[0107] In general, it should be noted in the method according to the invention that the markings 7, 8, 9 and the patterns 34, 37, 38 shown on the images 33, 36, 47 may be perspectively distorted due to the respective recording angles. This applies in particular to the second image 36, since the line of sight that occurs in connection with the second image 36 falls obliquely on the mirror 10 and the second display device 16. The perspective distortion caused by this should be taken into account, for example, when outputting the patterns 34, 37, 38 via the display devices 15, 16 and / or when specifically designing the markings 7, 8, 9, for example within the scope of a corresponding predistortion on the display devices 15, 16 or the markings 7, 8, 9. In the case of the figures shown here, this effect has not been taken into account for the sake of clarity and ease of understanding.

[0108] Next, according to Fig. 9 A second embodiment of the method according to the invention is explained, which can be used with Figure 3 The calibration assembly 14 shown in FIG. 1 is implemented in combination with the calibration assembly 14 shown in FIG. 1 , in which a camera 25 is provided instead of a calibrator 24. Figure 5 The method of explanation is similarly divided into a preparation phase 29 and a calibration phase 30 .

[0109] In the first step 54 of the method (which corresponds to Figure 5 In a first step 31 ) of the method explained in , the shutter 1 is arranged in the vehicle 4 in a temporary shutter position.

[0110] In the next step 55, a first image 33 is acquired from the perspective of the temporary detection position. The acquisition of the first image 33 is performed by means of the camera 25. For this purpose, the camera 25 is brought into the temporary detection position by means of the positioning device 26. Here, too, the temporary detection position is not a fixedly preset position of the camera 25, but can ultimately be selected arbitrarily in the region of the estimated driver's head position.

[0111] In steps 54, 55, the temporary shutter position and the temporary detection position can be selected manually, in particular by a calibrator 24 who is not located in the vehicle 4 in this embodiment, for example by operating the positioning device 26, so that at the beginning of this embodiment of the method, which can be basically automated, the first image 33 and the second image 36 respectively contain all the information required for positioning, namely the positioning marks 7, 8 and the positioning patterns 34, 37.

[0112] In the next step 56, according to Figure 6 The first misalignment information is determined from the exemplary first image 33 shown in FIG. 1 . For this purpose, the first image 33 is transmitted to the control device 28 , which is configured to determine the horizontal position deviation 39 and the vertical position deviation 40 in corresponding image evaluation software.

[0113] In the next step 57 of the method, a temporary detection position deviation and a temporary shutter position deviation are determined from the first misalignment information including the position deviations 39, 40. For this purpose, a corresponding lookup table or analytical relationship is stored in the control device 28, which analytical relationship can determine the resulting temporary detection position deviation and temporary shutter position deviation from the values ​​of the horizontal position deviation 39 and the vertical position deviation 40. However, these temporary deviations are not necessarily the deviations between the current position and the final position as provided in the first embodiment, because only the first image 33 has been recorded and evaluated so far, which alone is not sufficient to determine the final position unambiguously. The temporary detection position deviation and the temporary shutter position deviation are actually the required position changes of the shutter 1 and the camera 25, so that the horizontal position deviation 39 and the vertical position deviation 40 between the first positioning mark 7 and the first positioning pattern 34 in the first image become zero, and only the corresponding final position is approached at this time.

[0114] In the next step 58 , the control device 28 generates a control signal for operating the positioning device 26 , so that the temporary detection position of the camera 25 changes the temporary detection position deviation to another temporary detection position, and at this time approaches the final detection position.

[0115] Furthermore, in step 58, information about the temporary visor position deviation is output to the calibrator 24, for example via a monitor or the like, based on which the visor 1 is manually transferred to another temporary visor position. For this purpose, a further electromechanical actuator which can be controlled by means of the control device 28 can also be provided in the region of the fastening element 11 or the sun visor support 12. Changing the temporary visor position to another temporary visor position also results in an approach to the corresponding final position.

[0116] In a next step 59 , a second image 36 is acquired from the perspective of the further temporary detection position, with the shutter 1 arranged in the further temporary shutter position. This acquisition is also performed by means of the camera 25 .

[0117] According to Figure 7 36 (which is also transmitted to the control device 28), in the next step 60, second misalignment information is determined, which includes a possible horizontal position deviation 42 and a possible vertical position deviation 43 between the second positioning pattern 37 and the second positioning mark 8 on the second image 36. This is also achieved by the image evaluation software provided on the control device 28.

[0118] In the next step 61, the second misalignment information is evaluated similarly to the evaluation of the first misalignment information in step 57, wherein in the subsequent step 62, the shutter position and the detection position are changed again similarly to step 58, but under ideal conditions, they are not necessarily changed to the final detection position and the final shutter position.

[0119] In the next step 63, the calibration conditions are checked, wherein, if the calibration conditions are not met, the preparatory phase 29 is executed again, and the calibration phase 30 is started when the calibration conditions are met. Specifically, within the scope of this check, it is provided that the calibration conditions are met and the method is continued in the next step 64 when the detection position deviation and the shutter position deviation determined in the previous steps 57 and 61 are less than the corresponding preset limit values. In other words, the calibration conditions are met, which means that on the images 33, 36, the markings 7, 8 and the correspondingly associated patterns 34, 37 have already overlapped within the range of inaccuracies defined by the preset limit values. If there is no such overlap, that is, the detection position deviation or the shutter position deviation is greater than the preset limit value, the method is restarted in step 54 and the preparatory phase is executed again to determine and assume the position required for calibration. At this time, the preparatory phase 29 is therefore repeatedly executed as often as possible until the calibration conditions are met and the required final position is assumed.

[0120] If the calibration conditions are met, the method is continued, as already described, in step 64 , wherein a calibration image is acquired with the aid of the camera 25 , which is now also in the corresponding end position like the shutter 1 .

[0121] In a next step 65, the control device 28 is used to determine the calibration misalignment information, which includes Figure 8 Horizontal position deviation 50 and vertical position deviation 51 between calibration pattern 48 and calibration mark 9 on calibration image 47 are shown in FIG.

[0122] Based on the calibration offset information, a correction value is determined in a next step 66 , likewise, for example, based on a lookup table stored in the control device 28 or on a predefined analytical relationship between these variables.

[0123] In the next step 67 of the method, the image position correction is carried out similarly to step 53 of the first exemplary embodiment, but with the difference that the corresponding control commands are not generated by the calibrator 24 but by the control device 28 .

[0124] Next, in step 68, an end condition is checked, wherein the end condition is satisfied when the correction value determined in step 66 is less than a corresponding predefined limit value. If the end condition is satisfied, the method is terminated in a final step 69 and the calibration is successfully concluded. If the end condition is not satisfied, the calibration phase 30 starting from step 64 is executed again and the calibration is performed. Here, the calibration phase 30 also repeatedly executes the corresponding calibration steps 64 to 68 until the corresponding predefined limit value is fallen below and the calibration is concluded with sufficient accuracy defined by the corresponding limit value.

[0125] It is also conceivable that Figures 5 to 9 The various embodiments described are combined to form the method according to the invention. For example, it can be provided that the images 33, 36, 47 are acquired by means of the camera 25, wherein the images are transmitted to a corresponding output monitor or the like, and the position correction and calibration steps are performed by the calibrator 24.

Claims

1. A mask for correcting the image position of a virtual image (5) that can be projected onto a windshield (3) of a vehicle (4) by means of a head-up display (2), characterized in that: A first positioning mark (7), a second positioning mark (8) and a calibration mark (9) are provided on a plate (6) of the shield (1), and the plate (6) is transparent at least in the region of the first positioning mark (7), the second positioning mark (8) and the calibration mark (9), so that a first image (33), a second image (36) and a calibration image (47) can be acquired. The first image includes a first positioning mark (7) and a first positioning pattern (34) which is directly photographed through the plate (6) and output on the vehicle side. The second image contains a second positioning mark (8) and a second positioning pattern (37) output on the vehicle side, which is reflected by the mirror (10) of the shield (1) and photographed through the plate (6), The calibration image contains a calibration mark (9) and a calibration pattern (48) which is projected onto the windshield (3) by means of a head-up display (2) and is recorded directly through the pane (6).

2. The shield according to claim 1, characterized in that: The shield is movably fixed in the vehicle (4).

3. The shield according to claim 2, characterized in that: The cover is fixed in the vehicle (4) in a pivotable manner.

4. The shield according to claim 2 or 3, characterized in that: The sun visor is fixed on a sun visor bracket (12) of the vehicle (4).

5. The shield according to any one of claims 1 to 3, characterized in that: A mirror (10) is or can be arranged on the side of the plate (6).

6. The shield according to claim 5, characterized in that: A left-side mirror is arranged or can be arranged on the left side of the plate (6), and a right-side mirror is arranged or can be arranged on the right side of the plate (6).

7. The shield according to any one of claims 1 to 3, characterized in that: The plate (6) is made of transparent plastic at least in the region of the first positioning mark (7), the second positioning mark (8) and the calibration mark (9).

8. The shield according to claim 7, characterized in that: The plate (6) is made of organic glass at least in the region of the first positioning mark (7), the second positioning mark (8) and the calibration mark (9).

9. The shield according to any one of claims 1 to 3, characterized in that: The first positioning mark (7) and / or the second positioning mark (8) and / or the calibration mark (9) is or comprises at least one line and / or at least one cross and / or at least one rectangle and / or at least one circle.

10. The shield according to claim 9, characterized in that: The rectangle is a square.

11. A calibration component for correcting the image position of a virtual image (5) that can be projected onto a windshield (3) of a vehicle (4) by means of a head-up display (2), characterized in that: The calibration assembly (14) comprises: - a shutter according to any one of claims 1 to 10, a first display device (15) located on the vehicle side for outputting a first positioning pattern (34), - a second display device (16) located on the vehicle side for outputting a second positioning pattern (37), and - Head-up display (2) on the vehicle side.

12. The calibration assembly according to claim 11, characterized in that The first display device (15) is a first display (17) arranged on the dashboard (19) of the vehicle (4) on the driver's side, and / or the second display device (16) is a second display (18) arranged centrally on the dashboard (19) or the center console (20) of the vehicle (4).

13. The calibration assembly according to claim 12, characterized in that The first display can also be used as a speedometer.

14. The calibration assembly according to any one of claims 11 to 13, characterized in that The calibration component comprises a camera (25), by means of which a first image (33) and / or a second image (36) and / or a calibration image (47) can be acquired.

15. The calibration assembly according to claim 14, characterized in that The camera (25) is arranged on a positioning device (26), wherein the position of the camera (25) can be changed by means of the positioning device (26).

16. The calibration assembly according to claim 15, characterized in that The camera (25) is arranged on a robot (27) which is guided from the outside through a side window of the vehicle (4).

17. The calibration assembly according to claim 14, characterized in that The calibration component comprises at least one control device (28) which is configured to evaluate the first image (33) and / or the second image (36) and / or the calibration image (47) and / or to generate a control signal for image position correction.

18. The calibration assembly according to claim 17, characterized in that The control device is configured to generate a control signal for actuating an optical module (22) of a head-up display (2).

19. The calibration assembly according to claim 15, characterized in that The calibration component comprises at least one control device (28), which is configured to evaluate the first image (33) and / or the second image (36) and / or the calibration image (47), and / or generate a control signal for operating the positioning device (26), and / or generate a control signal for performing an image position correction.

20. The calibration assembly according to claim 19, characterized in that The control device is configured to generate a control signal for actuating an optical module (22) of a head-up display (2).

21. A method for correcting the image position of a virtual image (5) which can be projected onto a windshield (3) of a vehicle (4) by means of a head-up display (2), It is characterized in that The method comprises the following calibration preparation steps: a) arranging a shutter (1) according to any one of claims 1 to 10 in a temporary shutter position in a vehicle (4), b) acquiring a first image (33) from the perspective of at least one temporary detection position, c) acquiring a second image (36) from the perspective of the temporary detection position, d) determining first misalignment information, which is related to a possible position deviation (39, 40) between a first positioning pattern (34) and a first positioning mark (7) on a first image (33), e) determining second misalignment information, which is related to a possible position deviation (42, 43) between a second positioning pattern (37) and a second positioning mark (8) on a second image (36), f) determining a detection position deviation and a shutter position deviation according to the first misalignment information and / or the second misalignment information, wherein the detection position deviation describes a deviation between a temporary detection position and a final detection position, and the shutter position deviation describes a deviation between a temporary shutter position and a final shutter position, and g) according to the detection position deviation and / or the shutter position deviation, changing the temporary detection position to a final detection position or another temporary detection position, and changing the temporary shutter position to a final shutter position or another temporary shutter position, In order to correct the image position, the following steps are performed: h) acquiring a calibration image (47) from the perspective of the final detection position when the shutter (1) is arranged in the final shutter position, i) determining calibration misalignment information which is related to a possible positional deviation (50, 51) between a calibration pattern (48) and a calibration mark (9) on a calibration image (47), j) determining at least one correction value based on the calibration misalignment information, the correction value describing the parameter adjustment required for image position correction, wherein the correction value can be determined because the calibration image (47) has been acquired from the viewing angle of the final detection position and the shutter (1) is now arranged in the final shutter position, and k) Correcting the image position by changing at least one calibration parameter associated with the head-up display (2) by the correction value.

22. The method according to claim 21, characterized in that After step g) of the method, the calibration conditions are checked. When the calibration conditions are met, the method is continued in step h), and when they are not met, the method is restarted from step a), wherein the calibration conditions are met when the acquired detection position deviation and shutter position deviation are less than corresponding preset limit values.

Images