Three-dimensional augmented reality head-up display enabling virtual image to be located on ground by means of windshield reflection

Abstract

The invention discloses a three-dimensional augmented reality head-up display. A virtual image is located on the ground in a windshield reflection mode. A three-dimensional augmented reality head-up display includes: a display device functioning as a light source; and a free-form surface mirror that reflects light from the light source toward a windshield of a vehicle, the free-form surface mirror having a structure in which the light from the light source is reflected toward the windshield by means of a reflection method in which the light from the light source is reflected toward the windshield by means of the free-form surface mirror. An image formed by the light of the light source is focused on the ground in front of the vehicle as a virtual image of a three-dimensional viewpoint.

Description

[0001] This application is a divisional application of the Chinese invention patent application with application number 201980052703.X, application date October 10, 2019, and invention name “Three-dimensional augmented reality head-up display that uses windshield reflection to locate the virtual image on the ground”. Technical Field

[0002] The following description relates to a three-dimensional head-up display (Head-Up Display). Background Art

[0003] Figure 1 This is a diagram for explaining focus adjustment for information confirmation in a general head-up display device.

[0004] Reference Figure 1 A general vehicle head-up display (HUD) device is a vehicle display device as described below, that is, an image of the vehicle's current speed, remaining fuel, navigation route guidance information, etc. is output from a display 10 and the image is projected as a graphic image 14 to a windshield 13 directly in front of the driver through optical systems 11 and 12, so as to minimize the driver's unnecessary diversion of his or her sight to other places. Here, in order to change the optical path of the image output from the display 10, the optical systems 11 and 12 can be composed of a plurality of reflectors. The advantage of this vehicle head-up display device is that it provides convenience while guiding the driver's immediate response.

[0005] In general vehicle head-up display (HUD) devices, the position of the image is fixed about 2 to 3 meters in front of the user. When driving, the driver's gaze distance is close, that is, about 300 meters. As a result, the driver will drive while looking at a long distance, and in order to confirm the information of the head-up display (HUD) device during driving, it is necessary to adjust the focus of the eyes significantly, which is inconvenient. That is, the driver's focus adjustment is repeatedly performed between the long distance where the main field of view is located and the 3m distance where the image is formed.

[0006] Therefore, it is necessary to develop a three-dimensional head-up display (3D Head-Up Display) device to realize augmented reality in a driving environment to eliminate the limitation of image presentation distance, so that the driver can obtain the information he desires without changing the focus of the eyes under the gaze point during driving.

[0007] For example, Korean Patent No. 10-1409846 relates to a head-up display device based on three-dimensional augmented reality, and records the following technology related to the head-up display device, namely, image information enhanced by a three-dimensional image is represented in a stereoscopic manner based on actual distance information, thereby being able to provide reality information to the driver. Summary of the invention

[0008] Provided is a three-dimensional augmented reality head-up display capable of generating an augmented reality three-dimensional virtual image based on a driver's viewpoint by aligning a virtual image with the ground using a windshield reflection method.

[0009] Provided is a structure that maximizes the light efficiency of an optical system for generating a virtual 3D image that is consistent with the ground by including a windshield.

[0010] A three-dimensional augmented reality head-up display is provided, characterized in that it includes: a display device that plays the role of a light source; and a freeform surface mirror that reflects the light of the light source toward a windshield of a vehicle. The three-dimensional augmented reality head-up display includes the following structure: by reflecting the light of the light source toward the windshield by the freeform surface mirror, an image formed by the light of the light source is focused on the ground in front of the vehicle as a virtual image of a three-dimensional perspective.

[0011] According to one aspect, the windshield may include a function of reflecting the light of the light source reflected by the free-form surface reflector toward an eye-box while transmitting external light.

[0012] According to another aspect, a structure in which the display device is located on the close-range light side of the light extending toward the ground in order to focus the virtual image on the ground may include a structure in which the light from the light source is transmitted to the free-form surface reflector at a position lower than the free-form surface reflector.

[0013] According to another aspect, the three-dimensional augmented reality head-up display may further include a folding mirror for reducing the overall size of the light path, and the three-dimensional augmented reality head-up display may include a structure in which the light of the light source is transmitted in the order of the display device, the folding mirror, the free-form surface mirror, and the windshield, or the light of the light source is transmitted in the order of the display device, the free-form surface mirror, the folding mirror, and the windshield.

[0014] According to yet another aspect, a display plane corresponding to the display device can satisfy an imaging condition with a virtual image plane through the free-form surface reflector, and the virtual image plane is a plane corresponding to the ground.

[0015] According to yet another aspect, the virtual image may be generated based on an imaging condition among a display plane corresponding to the display device, a mirror plane corresponding to the free-form surface mirror, and a virtual image plane corresponding to the ground.

[0016] According to yet another aspect, the angle of the display device may be determined based on an angle of the display plane that satisfies the imaging condition.

[0017] According to yet another aspect, the angle of the display device may be determined based on an angle of the display plane, an angle of the windshield, and an angle of a folding mirror that satisfy the imaging condition.

[0018] According to yet another aspect, the angle of the free-form surface mirror may be determined based on the angle of the mirror plane that satisfies the imaging condition and the angle of the windshield.

[0019] According to another aspect, the starting position and size of the virtual image can be determined using the following angle: an angle that satisfies imaging conditions on the display plane and the virtual image plane, based on the point where the normal of the free-form surface reflector intersects the virtual image plane and the straight line through the optical center of the free-form surface reflector.

[0020] According to another aspect, the starting position and size of the virtual image can be adjusted by at least one of the angle, the angle of the display plane based on the virtual image plane, the angle between the display plane and the reflector plane, and the height from the virtual image plane to the optical center of the free-form surface reflector.

[0021] According to another aspect, the separation distance between the display device and the free-form surface reflector at the height from the virtual image plane to the free-form surface reflector can be derived by adding the height value obtained by adding the offset value in the height direction to the height from the virtual image plane to the optical center of the free-form surface reflector, the angle of the display plane with respect to the virtual image plane, the angle of the reflector plane with respect to the virtual image plane, and the angle between the display plane and the reflector plane.

[0022] According to yet another aspect, the position of the free-form reflector can be determined by a height including an offset value caused by a desired eye-box position.

[0023] According to the embodiments of the present invention, a 3D augmented reality head-up display can be provided which generates an augmented reality 3D virtual image based on the driver's viewpoint by making the virtual image consistent with the ground using windshield reflection.

[0024] According to the embodiments of the present invention, it is possible to provide a structure that maximizes the light efficiency of an optical system that generates a virtual 3D image that is consistent with the ground by including a windshield. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a diagram for explaining focus adjustment for information confirmation in a general head-up display device.

[0026] Figure 2 FIG. 1 is a diagram showing the image position of a three-dimensional augmented reality head-up display according to an embodiment of the present invention.

[0027] Figure 3 This is a diagram showing an example of providing an image on a virtual plane corresponding to a ground surface such as a road surface in one embodiment of the present invention.

[0028] Figure 4 FIG. 1 is a diagram showing an example of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0029] Figure 5 This is a diagram showing an example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0030] Figures 6 to 8 is a diagram showing a method for deriving a Figure 5 A diagram showing an equivalent representation of the theoretical relationship for the optical design structure.

[0031] Fig. 9 1 is a diagram showing another example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0032] Fig.10 This is a diagram showing another example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0033] Figures 11 to 13 is a diagram showing a method for deriving a Fig. 9 A diagram showing an equivalent representation of the theoretical relationship for the optical design structure.

[0034] Figures 14 to 17 It is a diagram for explaining the light efficiency involved in the optical design structure of the 3D augmented reality head-up display according to one embodiment of the present invention.

[0035] Fig.18 This is a diagram showing variables required for deriving a relationship equation between a display device and a free mirror of a three-dimensional augmented reality head-up display in one embodiment of the present invention.

[0036] Fig.19 It is a schematic diagram for explaining the position of the free reflector determined according to the eye-box (the position of the pupil) in one embodiment of the present invention.

[0037] Fig. 20 1 is a diagram showing imaging conditions among a display plane, a free mirror plane, and a virtual image plane in one embodiment of the present invention.

[0038] Fig.21 This is a diagram showing variables required for deriving the angles of a display device and a free mirror of a windshield reflection type 3D augmented reality head-up display according to one embodiment of the present invention. DETAILED DESCRIPTION

[0039] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0040] The embodiments described below may be modified in various other ways, and the scope of the present invention is not limited by the embodiments described below. In addition, these embodiments are provided to more completely explain the present invention to those skilled in the art. In order to make the description clearer, the shapes and sizes of the components in the drawings may be simplified, reduced or enlarged.

[0041] In addition to Figure 1 Except for the existing head-up displays described above, most displays such as TVs, monitors, projection screens, VR / AR glasses, etc. are placed vertically relative to the user's line of sight.

[0042] Embodiments of the present invention provide a 3D augmented reality head-up display with a 3D implementation method in which the position of an image corresponds to the ground. In particular, a 3D augmented reality head-up display that is most suitable for a driver's viewpoint in a driving environment can be provided by presenting a virtual screen as a 3D viewpoint lying in a manner corresponding to the ground.

[0043] Figure 2 FIG. 1 is a diagram showing the image position of a three-dimensional augmented reality head-up display according to an embodiment of the present invention.

[0044] Reference Figure 2 The three-dimensional augmented reality head-up display involved in the present invention can present the position of the virtual image, i.e., the virtual image 24, which can be seen by the user's eyes, as a three-dimensional viewpoint lying horizontally in a manner corresponding to the bottom surface in front of the driver, i.e., the ground 25.

[0045] The image formed by the optical system of a general vehicle head-up display is located at a fixed distance of 2 to 3 meters in front of the driver and is approximately perpendicular to the ground 25. Different from this, the three-dimensional augmented reality head-up display involved in the present invention is intended to make the virtual image 24 located on a virtual plane corresponding to the ground 25 in front of the driver's gaze.

[0046] The method adopted by the 3D augmented reality head-up display involved in the present invention is not to directly project on the screen to generate a real image like a general projector, but to generate a virtual image 24 that can be seen by the eyes through reflection through the optical system of the head-up display.

[0047] The main information provided by vehicle navigation corresponds to path information, lane information, distance information to the vehicle in front, etc. on the road being driven. In addition, ADAS (advanced driver-assistance system) provides the driver with information related to safety. At this time, the corresponding information mainly includes lane information, distance information to the vehicle in front / side, emergency information, etc. Similarly, when driving autonomously, it is necessary to provide passengers with information related to the situation that is about to occur in the driving subject's vehicle, such as turns on the road or lane changes. Path information, as information for guiding the path, can include TBT (turn-by-turn) information for guiding straight driving, turning, etc.

[0048] Reference Figure 3 It is very important and effective to display the above information, such as lane information 31 and distance information 32 to the vehicle ahead, in a virtual image on the actual road surface at the driver's point of view. Lane information 31, as information related to the lane being driven, may refer to driving information or navigation information to be displayed on the lane.

[0049] The three-dimensional augmented reality head-up display involved in the present invention can present the information to be conveyed to the user in augmented reality on the road surface that the user is actually looking at during driving in various driving environments by presenting the virtual screen as a three-dimensional viewpoint lying horizontally in a manner corresponding to the ground, without the user having to move the focus of his eyes from the viewpoint he is looking at during driving to other places.

[0050] Head-up display products for aftermarket products are mainly realized by a combiner method, but for built-in products, they are generally realized by a windshield reflection method in which image light is directly reflected onto the windshield of the vehicle without the presence of additional parts (combination).

[0051] The three-dimensional augmented reality head-up display involved in the present invention includes a combining function and an optical function (3D function), wherein the combining function refers to the function of combining the light from the light source with the external (panoramic) light and transmitting it to the driver's eyes, and the optical function (3D function) refers to the function of making the virtual image consistent with the ground in front of the driver and generating a three-dimensional augmented reality image based on the driver's viewpoint.

[0052] The three-dimensional augmented reality head-up display involved in the present invention utilizes a windshield reflection method, in which the windshield plays a combining function. In order to exert the 3D function, optical components including a freeform surface mirror (hereinafter referred to as a "freeform mirror") with optical power can be utilized.

[0053] Reference Figure 4 The three-dimensional augmented reality head-up display 400 involved in the present invention is a structure that generates a virtual 3D image by reflection, including a windshield 40, and may include: a display device 401, which plays the role of a light source; and a free reflector 402, which is used to reflect the light of the light source onto the windshield 40 and focus the virtual image on the ground in front of the driver. The windshield 40 may include the following functions: reflecting the light of the light source reflected by the free reflector 402 toward the eye-box (the position of the driver's eyes), while allowing external (front) light to pass through.

[0054] In other words, the 3D augmented reality head-up display 400 includes a structure that projects light from a light source onto the ground through the free reflector 402 and the windshield 40 , thereby enabling a virtual image to be located on the ground in front of the driver.

[0055] By deriving the positions and angles of the display device 401 and the free mirror 402 relative to the ground taking into account the angle of the windshield 40, a three-dimensional augmented reality head-up display 400 of windshield reflection type in which a virtual 3D image is located on the ground can be realized.

[0056] Figure 5 This is a diagram showing an example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0057] Reference Figure 5The windshield reflection type 3D augmented reality head-up display 400 of the present invention may further include a folding mirror 403 for reducing the overall size of the optical path, and the folding mirror 403 has a structure in which the light radiated from the display device 401 is located on the long-distance light side on the optical path of the image output from the display device 401 and is transmitted to the free reflector 402. Here, it is assumed that the windshield 40 and the folding mirror 403 have no optical power.

[0058] The long-distance ray may refer to the ray that forms the virtual image on the ground farthest from the driver among the rays that are radiated from the display device 401 and extend toward the ground in order to focus the virtual image on the ground. Conversely, the ray that forms the virtual image on the ground closest to the driver among the rays that are radiated from the display device 401 and extend toward the ground in order to focus the virtual image on the ground may be referred to as the short-distance ray.

[0059] Reducing the overall size of the light path means reducing the overall size of the area occupied by the path that the light passes through after being radiated from the display device 401 until it finally reaches the windshield. When the folding reflector 403 is used, although the overall length of the light path remains the same, the overall size of the area occupied by the light path can be reduced.

[0060] The light radiated from the display device 401 can be transmitted directly from the display device 401 to the free reflector 402, or it can be transmitted to the free reflector 402 after being reflected by the folding reflector 403. In this case, the light from the light source can be transmitted to the free reflector 402 at a position close to the long-distance light.

[0061] In order to facilitate the description of the derivation process of the theoretical relationship between the display device 401 and the free reflector 402 for focusing the virtual image on the ground, first, Figure 6 As shown, the path of light changed by the folding reflector 403 and the windshield 40 is represented by a simplified equivalent structure, that is, the folding reflector 403 and the windshield 40, which have no optical function other than changing the light path, are omitted from the illustration, and the position of the display device 401 is represented at a position symmetrical to the folding reflector 403. Figure 7 As shown, a display plane 71 corresponding to the display device 401, a freeform mirror plane 72 corresponding to the freeform mirror 402, and an image plane 73 corresponding to the ground are added, and then as shown in Figure 8 As shown, the virtual image plane 73 is rotated to be parallel to the ground and is shown in a state in which it is flipped left and right with respect to the Y axis (the axis in the vertical direction in the figure).

[0062] Reference Figure 8 The three-dimensional augmented reality head-up display 400 of windshield reflection type may include the following structure: a structure in which light radiated from the display device 401 is transmitted to the free reflector 402 at a position higher than the free reflector 402. In other words, among the light radiated to the ground in order to focus the virtual image on the ground, the display device 401 is located on the side of long-distance light farther from the driver's position than the short-distance light closer to the driver's position.

[0063] Fig. 9 1 is a diagram showing another example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention, Fig.10 This is a diagram showing another example of the optical design structure of a windshield reflection type 3D augmented reality head-up display according to an embodiment of the present invention.

[0064] Reference Fig. 9 and Fig.10 The windshield reflection type 3D augmented reality head-up display 400 of the present invention may further include a folding reflector 403 for reducing the overall size of the optical path, and the folding reflector 403 has a structure in which the light radiated from the display device 401 is located on the short-distance light side on the optical path of the image output from the display device 401 and is transmitted to the free reflector 402. Similarly, it is assumed that the windshield 40 and the folding reflector 403 have no optical power.

[0065] The light radiated from the display device 401 can be transmitted directly from the display device 401 to the free reflector 402, or it can be transmitted to the free reflector 402 after being reflected by the folding reflector 403. In this case, it can be realized by a structure in which the light of the light source is transmitted to the free reflector 402 at a position close to the short-distance light.

[0066] Fig. 9 The structure in which the path of light travels is composed of the display device 401, the folding reflector 403, the free reflector 402, the windshield 40, and the driver in this order. Fig.10 As shown, it can also be implemented with a structure in which light is transmitted in the order of display device 401, free reflector 402, folding reflector 403, and windshield 40.

[0067] against Fig. 9 In order to facilitate the description of the derivation process of the theoretical relationship between the display device 401 and the free reflector 402 for focusing the virtual image on the ground, firstly, Fig.11As shown, the path of light changed by the folding reflector 403 and the windshield 40 is represented by a simplified equivalent structure, that is, the folding reflector 403 and the windshield 40, which have no optical function other than changing the light path, are omitted from the illustration, and the position of the display device 401 is represented at a position symmetrical to the folding reflector 403. Fig.12 As shown, a display plane 71 corresponding to the display device 401, a free reflector plane 72 corresponding to the free reflector 402, and a virtual image plane 73 corresponding to the ground are added. Fig.13 As shown, the virtual image plane 73 is rotated to be parallel to the ground and is shown in a state in which it is flipped left and right with respect to the Y axis (the axis in the vertical direction in the figure).

[0068] Reference Fig.13 The three-dimensional augmented reality head-up display 400 of windshield reflection type may include the following structure: the light radiated from the display device 401 is transmitted to the free reflector 402 at a position lower than the free reflector 402. In other words, in the light radiated toward the ground in order to focus the virtual image on the ground, the display device 401 is located on the short-distance light side close to the driver's position.

[0069] When comparing the outputs of light radiated from the display device 401 at various angles, it can be found that the output of the vertical component is the highest, and the output becomes lower as it moves away from vertical. Therefore, it can be said that from the perspective of light efficiency, it is preferable to use light at a vertical angle or light close to a vertical angle.

[0070] According to the representation Figure 5 Optical design structure Figure 8 The equivalent structure of Fig.14 As shown, the display device 401 is located above the free reflector 402 and is located on the long-distance light side in front of the driver.

[0071] like Fig.15 As shown, it will reflect Figure 5 Optical design structure Figure 8 After the equivalent structure is rotated to make the free reflector plane 72 vertical, it can be found that most of the light with a strong vertical component output from the light radiated from the display device 401 is discarded, and the light with a component far from the vertical and relatively low output is mainly used, so the light efficiency may be reduced.

[0072] In order to apply an optical design structure in which the display device 401 is located at a higher position than the free reflector 402 to the three-dimensional augmented reality head-up display 400 of the windshield reflection method, light efficiency can be ensured by utilizing a display device capable of adjusting the radiation angle of light, that is, a display device including other optical elements such as a diffraction element, a micro-lens array (Micro-Lens Array), and a digital micromirror device (Digital Micromirror Device).

[0073] On the other hand, according to the Fig. 9 Optical design structure Fig.13 The equivalent structure of Fig.16 As shown, the display device 401 is located below the free reflector 402 and is thus located on the short-range light side in front of the driver.

[0074] like Fig.17 As shown, it will reflect Fig. 9 Optical design structure Fig.13 After the equivalent structure is rotated to make the free reflector plane 72 vertical, it can be found that the light radiated from the display device 401 is mainly used to output a strong vertical component, so it can be said that the light efficiency is high.

[0075] The actual path of light movement is that it starts from the display device 401 and is reflected by the free reflector 402 and the windshield 40. At this time, the reflected light reaches the driver's eyes and is focused on the retina by the lens. However, the image seen by the user is not the real image of the display plane 71 position that generates the actual image, but the virtual image 24. At this time, the virtual image 24 is located on the virtual plane corresponding to the ground, that is, the virtual image plane 73. That is, the display plane 71 meets the imaging condition with the virtual image plane 73 through the free reflector 402.

[0076] The theoretical relationship between the display device 401 and the free mirror 402 for generating a virtual image at a ground position can be derived based on the imaging conditions among the display plane 71 corresponding to the display device 401, the free mirror plane 72 corresponding to the free mirror 402, and the virtual image plane 73 corresponding to the ground, except for the user's eyes. In addition, the focal distance of the free mirror plane 72 can be one of the variables of the imaging conditions.

[0077] Fig.18 4 is a diagram showing variables required for deriving a relational expression between the display device 401 and the free mirror 402 .

[0078] Reference Fig.18, the intersection point I of the display plane 71 and the free mirror plane 72 can be located on the ground. In other words, the display plane 71, the free mirror plane 72 and the virtual image plane 73 can intersect at the same time at a predetermined position I. Under this condition, the optical system can be set so that the display plane 71, the free mirror plane 72 and the virtual image plane 73 meet the imaging condition.

[0079] DP refers to a display plane 71 corresponding to the display device 401 , FMP refers to a free mirror plane 72 corresponding to the free mirror 402 , and IP refers to a virtual image plane 73 representing the plane itself corresponding to the ground.

[0080] C refers to the optical center of the free reflector 402 relative to the display device 401. However, C does not actually necessarily need to be located on the free reflector 402, and an offset value can be applied to the position of the free reflector 402 according to the position of the user's line of sight. The higher the position of the user's line of sight is set, the larger the offset value can be set, and the lower the position of the user's line of sight is set, the smaller the offset value can be set. Accordingly, the higher the position of the user's line of sight is set, the higher the free reflector 402 can be set, and the lower the position of the user's line of sight is set, the lower the free reflector 402 can be set. However, the mathematical relationship between the entire optical system and the internal components can remain the same regardless of this change.

[0081] In the following, for the convenience of expressing mathematical formulas, it is assumed that C is located on the free reflection mirror 402 to derive the relationship.

[0082] I is the intersection point where DP71, FMP72 and IP73 intersect, J is the point where a straight line parallel to DP71 and passing through the center point C intersects IP73, and K is the intersection point on IP73 that intersects the normal line of the free reflector 402, which refers to the point where a straight line perpendicular to FMP72 and passing through the center point C intersects IP73.

[0083] α(α E , α S ) is used as the angle of the position on DP71 and IP73 that meets the imaging condition based on the straight line passing through the center point C and the intersection point K. Since the corresponding position meets the imaging condition, the DP71 direction angle and the IP73 direction angle are always consistent. Here, the imaging condition refers to the condition that the light emitted from the light source in an all-round solid angle reaches the same location of the virtual image VI through the free reflector. Fig.18Satisfying the imaging condition means that as the positions and angles of the display device 401, the free reflector, and the IP73 forming the virtual image VI, and the focal length f of the free reflector satisfy the lens formula, the light emitted from the display device 401 converges on the IP73 through the free reflector, thereby generating a virtual image VI on the IP73. However, since the embodiments of the present invention illustrate an example of forming a virtual image VI rather than a real image, the light does not actually reach the IP73, but the extended line of the emitted light converges on the IP73 to form the virtual image VI, which is clear to those skilled in the art.

[0084] β refers to the angle of DP71 with respect to IP73 or the ground, γ refers to the angle of FMP72 with respect to IP73 or the ground, and θ refers to the angle between DP71 and FMP72.

[0085] h is the distance from IP73 or the ground to the center point C, h' (refer to Fig.19 ) is the value obtained by adding the offset value (positive or negative) in the h direction to h (the actual height of the free reflector 402). In this case, h' corresponds to the case where the offset value caused by the position of the user's line of sight is applied to the position of the free reflector 402.

[0086] S refers to the length between the intersection point I and the intersection point J, that is, the separation distance between the DP 71 and the FMP 72 at a height h in an axial direction parallel to the ground.

[0087] S'(ref. Fig.19 ) refers to the axis parallel to the ground at a height h' (refer to Fig.19 ) is the separation distance between DP71 and FMP72 at .

[0088] d S It refers to the distance from the orthogonal position C′ of the center point C of the free reflection mirror 402 and the IP73 or the ground to the position where the virtual image VI starts on the plane corresponding to the IP73 or the ground.

[0089] d E It refers to the distance from the orthogonal position C′ of the center point C of the free reflector 402 and the IP73 or the ground to the position where the virtual image VI ends on the plane corresponding to the IP73 or the ground.

[0090] d I refers to the size of the virtual image VI, and f refers to the focal length of the free reflection mirror 402.

[0091] First, the relationship between β, γ and θ is as follows.

[0092] When imaging conditions between DP71 and IP73 are applied, the following Mathematical Formula 1 holds true.

[0093] [Mathematical formula 1]

[0094]

[0095] (γ, θ, h, and f are all assumed to be positive numbers)

[0096] Here, h refers to the height from the ground to the position of the 3D augmented reality head-up display 400 on the dashboard of a general vehicle (more precisely, the height to the optical center C of the free reflector 402). And, f refers to the focal length of the free reflector 402 of the 3D augmented reality head-up display 400 having a general size and curvature.

[0097] When the values ​​of h and f are substituted into Mathematical Formula 1, the numerical relationship between θ and γ can be derived, and on this basis, β can be derived through the relationship between β, γ and θ: β=γ+θ.

[0098] Next, S can be derived using equation 2 using h, β, γ, and θ.

[0099] [Mathematical formula 2]

[0100]

[0101] Finally, d can be derived by mathematical formula 3 S ,d E and d I .

[0102] [Mathematical formula 3]

[0103] d S =htan(γ+α S )

[0104] d E =htan(γ+α E )

[0105] d I =h(tan(γ+α E )-tan(γ+α S ))

[0106] (α(α E , α S ) is a positive or negative number based on the straight line passing through the center point C and the intersection point K)

[0107] d can be calculated by equation 3 S and d IAt this time, if you need to change the d representing the starting position of the virtual image VI S and d representing the size of the virtual image VI I To adjust, you can adjust α(α E , α S ), at least one of β and θ to achieve the optimization of the optical structure.

[0108] The above relationship can be used to derive the angles of DP71 and FMP72 relative to the ground and the position and size of the virtual image VI.

[0109] Fig.19 1 is a diagram for explaining an example of the position of the free mirror 402 determined according to the eye-box (the position of the pupil) in the three-dimensional augmented reality head-up display 400 .

[0110] Reference Fig.19 The required height of the eye-box (the position of the pupil) can generally be determined by the height of the driver's eyes when sitting in the driver's seat of the vehicle, while the distance between the eye-box and the free reflector 402 is determined by the distance from the eye to the free reflector 402 of the three-dimensional augmented reality head-up display 400.

[0111] For the position of the free reflector 402, the height h' is determined according to the position of the desired eye zone and includes an offset value, and its position does not necessarily need to include the optical center C of the free reflector 402. According to h', the separation distance s' between DP71 and FMP72 can be determined, and at this time, s' can be regarded as the distance between the display device 401 and the free reflector 402.

[0112] Will manifest Fig. 9 Optical design structure Fig.13 The equivalent structure of is rotated to make the free reflector plane 72 vertical, and it can be found that Fig. 20 As shown, for the angle α (α E , α S ), the DP71 direction angle is consistent with the IP73 direction angle.

[0113] It goes without saying that the display device 401 is located close to the short-distance light. Even if the display device 401 is located close to the long-distance light, the position angle (α) between the light source and the virtual image is also E , α S ) is always unified.

[0114] Fig.21Variables required to derive the angles of the display device 401 and the free mirror 402 taking into account the windshield 40 and the folding mirror 403 are shown in FIG. Fig.21 , an optical design structure of a structure in which the display device 401 is located close to the short-distance light is shown.

[0115] Reference Fig.21 , δ refers to the angle of the display device 401 with respect to the ground, ε refers to the angle of the free reflector 402 with respect to the ground, σ refers to the angle of the folding reflector 403 with respect to the ground, and τ refers to the angle of the windshield 40 with respect to the ground.

[0116] Based on Fig.18 The theoretical relationship between the display device 401 and the free reflector 402 described above is used to derive the angle between the display device 401 and the free reflector 402 as follows.

[0117] The angle of the display device 401 can be derived using the angle β of the DP71 that satisfies the imaging condition, and can be derived using Equation 4 or Equation 5 as an example.

[0118] [Formula 4]

[0119] δ=β+2×(τ-σ)(if σ≠τ)

[0120] [Formula 5]

[0121] δ=β(if σ=τ)

[0122] The angle of the free reflection mirror 402 can be derived using the angle γ of the FMP 72 that satisfies the imaging condition, and can be derived using Mathematical Formula 6 as an example.

[0123] [Mathematical formula 6]

[0124] ε=γ+2τ

[0125] Therefore, the three-dimensional augmented reality head-up display 400 involved in the present invention can realize a virtual image VI of a three-dimensional viewpoint lying on the ground in front of the driver's gaze through a display device 401 and a free reflector 402 based on the above relationship and using a windshield reflection method.

[0126] At a position where the imaging conditions between DP71 and IP73 are satisfied, the angle β of DP71 is used to derive the angle of the display device 401 with respect to the ground, and the angle γ of FMP72 is used to derive the angle of the free reflector 402 with respect to the ground, thereby realizing a three-dimensional augmented reality head-up display 400 in which a virtual 3D image is located on the ground through windshield reflection.

[0127] As described above, according to an embodiment of the present invention, a three-dimensional augmented reality head-up display can be provided that utilizes windshield reflection to make the virtual image consistent with the ground and generates an augmented reality three-dimensional virtual image based on the driver's viewpoint. In particular, a structure that utilizes a structure including a windshield to maximize the light efficiency of an optical system used to generate a virtual 3D image consistent with the ground can be provided.

[0128] The apparatus described above can be implemented using hardware components, software components and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiment can be implemented using one or more general-purpose computers or specific target computers such as a processor, a controller, an ALU (arithmetic logic unit), a digital signal processor (digital signal processor), a microcomputer, an FPGA (field programmable gate array: field programmable gate array), a PLU (programmable logic unit: programmable logic unit), a microprocessor, or any other device capable of executing instructions (instruction) and responding. The processing device can execute an operating system (OS) and one or more software applications executed on the operating system. In addition, the processing device can access, store, operate, process and generate data in response to the execution of the software. For ease of understanding, sometimes the case of using a processing device is described, but those skilled in the art should understand that the processing device may include multiple processing elements (processing element) and / or multiple types of processing elements. For example, the processing device may include multiple processors or a processor and a controller. In addition, other processing configurations such as parallel processors may also be used.

[0129] Software may include a computer program, code, instruction, or a combination of more than one of these, and may constitute a processing device in a manner that performs a desired action or command a processing device in an independent manner or in a collective manner. Software and / or data may be embodied in a certain type of device, component, physical device, computer storage medium, or device in order to be parsed by a processing device or to provide instructions or data to a processing device. Software may be distributed on computer systems connected via a network, or may be stored or executed in a distributed manner. Software and data may be stored in one or more computer-readable media.

[0130] The method involved in the embodiment can be implemented in the form of program instructions that can be executed by various computer units and recorded in a computer-readable medium. At this time, the medium can store the program that can be executed by the computer all the time or temporarily store it for execution or downloading. In addition, the medium can be a variety of recording units or storage units in the form of a single or multiple hardware combinations, but is not limited to the medium directly connected to a certain computer system, and can also be dispersed on the network. As an example of the medium, magnetic media such as hard disks, floppy disks and tapes, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floppy disks (magneto-optical medium), ROM, RAM, flash memory, etc. can be included to form a storage program instruction language. In addition, as an example of other media, the recording medium managed by the application mall that sells application programs or the webpages, servers, etc. that supply or sell various other software can also be listed to store the program instructions.

[0131] Modes for carrying out the invention

[0132] As described above, although the embodiments are described through limited embodiments and drawings, those skilled in the art can make various modifications and variations based on the above description. For example, the described techniques can be performed in a different order than the described method, and / or the described systems, structures, devices, circuits and other components can be combined or combined in a different form than the described method, and even if they are replaced or substituted by other components or equivalent elements, appropriate results can be achieved.

[0133] Therefore, other implementations, other examples, and equivalents thereof are also within the scope of the appended claims.

Claims

1. A three-dimensional augmented reality head-up display, characterized in that: include: a display device, serving as a light source; and A free-form reflector reflects the light from the light source toward the windshield of the vehicle, The three-dimensional augmented reality head-up display includes the following structure: by reflecting the light of the light source toward the windshield by the free-form surface reflector, an image formed by the light of the light source is focused on the ground in front of the vehicle as a virtual image of a three-dimensional viewpoint, The virtual image is generated based on imaging conditions between a display plane corresponding to the display device, a reflector plane corresponding to the free-form surface reflector, and a virtual image plane corresponding to the ground. The imaging condition is a lens formula in which the light from the display device is focused on the virtual image plane by the free-form surface reflector. When the imaging condition is satisfied, determining a separation distance (S) between the display device (401) and the free-form surface reflector (402) based on a height value (h) from the virtual image plane (IP) to the optical center (C) of the free-form surface reflector (402), a first angle (β) between the display plane (DP) and the virtual image plane (IP), a second angle (γ) between the reflector plane (FMP) and the virtual image plane (IP), and a third angle (θ) between the display plane (DP) and the reflector plane; The separation distance is the distance between a point (I) where the display plane meets the virtual image plane and a point (J) where a straight line parallel to the display plane and passing through the optical center intersects the virtual image plane; and h is the height value; γ is the second angle; θ is the third angle; f is the focal length of the free-form surface reflector.

2. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The windshield has a function of reflecting the light of the light source reflected by the free-form surface reflector toward the eye area while transmitting external light.

3. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The display device is located on the short-distance light side of the light extending toward the ground in order to focus the virtual image on the ground, including a structure in which the light from the light source is transmitted to the free-form surface reflector at a position lower than the free-form surface reflector.

4. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The three-dimensional augmented reality head-up display also includes a folding reflector for reducing the overall size of the light path, The three-dimensional augmented reality head-up display includes a structure in which the light from the light source is transmitted in the order of the display device, the folding reflector, the free-form surface reflector, and the windshield, or the light from the light source is transmitted in the order of the display device, the free-form surface reflector, the folding reflector, and the windshield.

5. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The display plane satisfies the imaging condition with the virtual image plane through the free-form surface reflector.

6. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The angle of the display device is determined based on the first angle of the display plane that satisfies the imaging condition.

7. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The angle of the display device is determined based on the first angle of the display plane that satisfies the imaging condition, the angle of the windshield, and the angle of the folding mirror.

8. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The angle of the free-form surface mirror is determined based on the second angle of the mirror plane that satisfies the imaging condition and the angle of the windshield.

9. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The starting position and size of the virtual image are determined by using the fourth angle described below: an angle that satisfies imaging conditions on the display plane and the virtual image plane, based on the point where the normal of the free-form surface reflector intersects the virtual image plane and the straight line of the optical center of the free-form surface reflector.

10. The three-dimensional augmented reality head-up display according to claim 9, characterized in that: The starting position and size of the virtual image are adjusted by determining at least one of the fourth angle for determining the starting position and size of the virtual image, the first angle of the display plane, the third angle between the display plane and the reflector plane, and the height from the virtual image plane to the optical center of the free-form surface reflector.

11. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The separation distance between the display device and the free-form surface reflector at the height from the virtual image plane to the free-form surface reflector is derived by adding the height value obtained by adding the offset value in the height direction to the height from the virtual image plane to the optical center of the free-form surface reflector, the first angle of the display plane, the second angle of the reflector plane, and the third angle between the display plane and the reflector plane.

12. The three-dimensional augmented reality head-up display according to claim 1, characterized in that: The position of the free-form surface reflector is determined by the height including an offset value caused by the required position of the eye zone.

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