JP7025439B2 - Split exit pupil head-up display system and method - Google Patents

Description

The present invention relates generally to a heads-up display (HUD), and more particularly to a HUD system that produces one or more virtual images.

The head-up display contributes to the safety of the vehicle by allowing the driver of the vehicle to more visually recognize and notify the dashboard information of the vehicle without removing the driver's view and attention from the road. It is required as an auxiliary technology. However, currently available heads-up displays are bulky and too expensive to be a viable option for use in most vehicles. Applications for aircraft and helicopter head-up displays also experience these same obstacles, albeit to a lesser extent as a cost factor. For automotive applications of heads-up displays, volume and cost constraints are exacerbated by the variety of vehicle sizes, types and cost requirements. Therefore, there is a demand for low cost and low bulk head-up displays suitable for use in small vehicles such as automobiles, small aircraft, and helicopters.

Conventional HUD systems can generally be classified into two types: pupillary imaging HUD and non-pupil imaging HUD. The pupil imaging HUD is typically a relay module responsible for delivering intermediate images and forming pupils, as well as image collimation and the position of the viewer's eyes (in the present specification, the "eye-box"). It consists of a collimation module that is in charge of imaging the pupil in (called). Collimation modules for pupil imaging HUDs are typically implemented as tilted curved or planar reflectors, or holographic optical elements (HOEs), and relay modules are typically for bending the optical path and for photoaberration. Inclined to compensate. The non-pupil imaging HUD defines the aperture of the system by the angle of the light cone at the position of the intermediate image on the display or due to diffusion. The intermediate image HUD system also requires a relay module, but the HUD aperture is determined only by the collimation optical system. Collimation optics usually have axial symmetry, but are equipped with folding mirrors to meet the volume requirements. This is determined by the need for aberration correction and aspects of the volume of the system.

The prior art described in Patent Document 8 and illustrated in FIG. 1-1 minimizes the collimation optical system by using a concave HOE reflector (11 in FIG. 1-1) as a combiner and collimator, and is a HUD system. Reduce the volume aspect of the. The resulting HUD system requires complex tilt relay optics (10 in FIG. 1-1) to compensate for aberrations and deliver intermediate images. Moreover, this HUD system only works in a narrow spectrum.

The prior art described in Patent Document 9 and illustrated in FIG. 1-2 uses a relay optical system (REL) module to convergent combiner (CMB) mirror (CMB in FIG. 1-2). ) Deliver an intermediate image to the focal plane and define the pupil of the system. The CMB mirror collimates the intermediate image and forms the pupil of the system into the viewer's eye to promote viewing. This pupil imaging HUD approach inevitably involves a complex REL module for packaging and aberration correction.

The prior art described in Patent Document 10 and illustrated in FIG. 1-3 uses a projection lens (3) for projecting onto a diffused surface (51 in FIGS. 1-3) as an image source and is also half. A transparent collimated mirror (7 in Fig. 1-3) is used. The collimated mirror forms an image at point at infinity, and the aperture of the collimation optical system is defined by the angular width of the diffuser.

The prior art described in Patent Document 11 and illustrated in FIG. 1-4 is collimated using an image forming source consisting of two liquid crystal display (LCD) panels (23 in FIG. 1-4). An intermediate image is formed on a diffusion screen (5 of FIG. 1-4) arranged on the focal plane of the optical system module (1 of FIG. 1-4). The main purpose of the two LCD panels of the image forming source is to achieve sufficient brightness for the visibility of the formed image. To this end, the two LCD panels of the image forming source form or overlap two consecutive side-by-side images on the diffuse screen, 1/2 horizontally and vertically on the diffuse screen. It is configured to form two images that are shifted by pixels.

The prior art described in Patent Document 12 uses a pair of reflective holographic optics (HOEs) to achieve holographic dispersion correction and to provide a virtual image of a broadband display source within the field of view of the observer. Project. The prior art described in Patent Document 13 also uses a pair of holographic optics (HOEs), one transparent and the other reflective, to project an image onto the windshield of the vehicle.

The prior art described in Patent Document 14 and illustrated in FIG. 1-5 is a vehicle configured to project an image onto a vehicle dashboard (18 in FIG. 1-5) having a faceted reflective surface. An image projector installed above the windshield (14 in FIGS. 1-5) is used, where the facet reflective surface is configured to reflect the image from the image projector onto the windshield of the vehicle. The surface of the vehicle windshield is oriented to reflect images from each of the dashboard facet surfaces towards the viewer.

U.S. Pat. No. 7,623,560, El-Ghoroury et al, Quantum Photonic Imager and Methods of Fabrication Thereof, Nov. 24, 2009. U.S. Pat. No. 7,767,479, El-Ghorory et al, Quantum Photonic Imager and Methods of Fabrication Thereof U.S. Pat. No. 7,829,902, El-Ghorory et al, Quantum Photonic Imager and Methods of Fabrication Thereof U.S. Pat. No. 8,049,231, El-Ghorory et al, Quantum Photonic Imager and Methods of Fabrication Thereof U.S. Pat. No. 8,098,265, El-Ghorory et al, Quantum Photonic Imager and Methods of Fabrication Thereof US Publication No. 2010/0066921, El-Ghorory et al, Quantum Photonic Imager and Methods of Fabrication Thereof US Patent No. 2012/0033113, El-Ghoroury et al, Quantum Photonic Imager and Methods of Fabrication Thereof U.S. Pat. No. 4,218,111, Withrington eta al, Holographic Heads-up Displays, Aug. 19, 1980 U.S. Pat. No. 6,813,086, Signolles et al, Head Up Display Device to Given Type of Equipment, Nov. 2, 2004 U.S. Pat. No. 7,391,574, Fredricksson, Heads-up Displays, June 24, 2008 U.S. Pat. No. 7,982,959, L'vovskiy et al, Heads-up Displays, Jul. 19, 2011 U.S. Pat. No. 4,613,200, Hartman, Heads-Up Display System with Holographic Dispersion Direction, Sep. 23, 1986 U.S. Pat. No. 5,729,366, Yang, Heads-Up Display for Vehicle Using Holographic Optical Elements, Mar. 17, 1998 U.S. Pat. No. 8,553,334, Lambert et al, Heads-Up Display System tilizing Controlled Reflection from Dashboard Surface, Oct. 8, 2013 U.S. Pat. No. 8,629,903, Seder et al, Enhanced Vision System Full-Windshided HUD, Jan. 14, 2014

B. H. Walker, Optical Design of Visual System, Tutorial tests in optical engineering, public by The international Engineering of Optical 139-150, ISBN 0-8194-3886-3, 2000 C. Guilloux et al, Varilux S Series Braking the Limits M. Born, Polypropylene of Optics, 7th Edition, Cambridge University Press 1999, Section 5.3, pp. 236-244

Common to the prior art HUD system described briefly and the plurality of other HUD systems described in the cited prior art is the high cost and large volume size of the system. Moreover, none of the prior art HUD systems can be scaled in size and cost to fit the size and price range of various vehicles and other vehicles. Therefore, an object of the present invention is a method for a head-up display using a plurality of luminescent microscale pixel array imagers in order to realize a HUD system having a significantly smaller volume than a HUD system using a single image forming source. Is to introduce. Further, an object of the present invention is to enable a modular HUD system having a volumetric and cost aspect that can be scaled to fit various vehicle and small vehicle sizes and price ranges. We will introduce a method for designing a new split exit pupil HUD system using a microscale pixel array imager. Further objects and advantages of the invention will become apparent from the following detailed description of preferred embodiments of the invention, which proceed with reference to the accompanying drawings.

In the following description, similar drawing reference numerals are used for similar elements in different drawings. The things defined in this description, such as the structures and design elements detailed, are provided to aid in a comprehensive understanding of exemplary embodiments. However, the present invention can be practiced without the use of these specifically defined things. Further, the known functions or structures will not be described in detail because they obscure the present invention by unnecessary details. Some embodiments of the invention, with reference to the accompanying drawings, are merely non-limiting examples to understand the invention and to confirm how the invention can be practiced in practice. Will be described below.

FIG. 1-1 shows a prior art head-up display (HUD) system that uses concave HOE reflectors as combiners and collimators to minimize collimation optics and reduce volume aspects of the HUD system. Figure 1-2 shows a prior art head-up display (HUD) system that uses a relay optical system (REL) module to deliver an intermediate image to the focal plane of a convergent combiner (CMB) mirror to define the pupil of the system. Is shown. FIG. 1-3 shows a prior art head-up display (HUD) system using a projection lens (3) for projection onto a diffuse surface as an image source and also using a translucent collimating mirror. Figure 1-4 shows a prior art head-up display that uses an image forming source consisting of two liquid crystal display (LCD) panels to form an intermediate image on a diffuse screen located at the focal plane of a collimation optical system module. (HUD) Indicates a system. FIG. 1-5 uses an image projector installed above the windshield of a vehicle configured to project an image onto a vehicle dashboard with a facet reflective surface, wherein the facet reflective surface is: Demonstrates a prior art head-up display (HUD) system configured to reflect an image from an image projector onto the windshield of a vehicle. FIG. 2 shows an exemplary modular HUD (MHUD) system of the present invention. FIG. 3 shows the relationship between the design parameters and constraints of the MHUD system of FIG. FIG. 4 shows an optical design aspect and a ray trace diagram of a HUD module comprising the MHUD assembly of the embodiment of FIG. FIG. 5 shows the optical performance of a HUD module with the MHUD assembly of the embodiment of FIG. FIG. 6 shows a multi-view perspective view of an MHUD assembly design example of the MHUD system according to the embodiment of FIG. FIG. 7 shows a functional block diagram of an interface and a control electronic component design element (board) of the MHUD system according to the embodiment of FIG. FIG. 8 shows a novel split eyebox design method for the MHUD system 200 of the embodiment of FIG. FIG. 9 shows the actual volume of the MHUD assembly design example shown in FIG. 6 installed on the dashboard of a quasi-small vehicle. FIG. 10 shows the ray path of the MHUD system of the present invention, including the load of sunlight. 11A and 11B show front and side views of the solid-state luminescent pixel array imager (ie, display element) of the embodiment of the multi-image HUD system of the invention, respectively, in which odd-numbered rows of pixels are generally imagers. A second image that indicates that it has an output that will produce a first image projected outward from the surface of the, and that even rows of pixels are generally projected somewhat downward with respect to the first image. Indicates that it has an output that will produce an image. 11C and 11D show front and side views of the solid-state luminescent pixel array imager of the embodiment of the multi-image HUD system of the present invention, respectively, which are the solid-state luminescent pixel array imagers (ie, display elements). The pixels in the upper region will have the output that will produce the second image described above, and the pixels in the lower region of the solid state luminescent pixel array imager will produce the first image described above. Indicates that it has an output. FIG. 12 shows a plurality of ray paths according to an embodiment of the multi-image HUD system of the present invention. FIG. 13 shows the nominal positions of the near-field virtual image and the far-field virtual image in the low-volume package design of the embodiment of the multi-image HUD system of the present invention installed on the dashboard of a semi-small vehicle. FIG. 14 shows a side view of a display element of the present invention comprising a plurality of non-telecentric refracting micro-optical elements. FIG. 15 shows a side view of a display element of the present invention comprising a plurality of tilted refraction microoptical elements.

References to "one embodied" or "an embodied" in the following detailed description of the invention are specific feature portions, structures or or described in connection with the embodiment. It means that the feature is included in at least one embodiment of the present invention. The phrase "in one embodied" appears in various places in this detailed description, but not all of them necessarily refer to the same embodiment.

In recent years, a new classification of luminescent microscale pixel array imager devices has been introduced. These devices are extremely small device sizes, including all required image processing drives, and are equipped with high brightness, extremely rapid multicolor light intensity, and spatial modulation capabilities. The solid state light (SSL) emission pixel of one such device may be a light emitting diode (LED) or a laser diode (LD), and these on / off states are the luminescent properties of the imager described above. It is controlled by a drive circuit contained in a CMOS chip (or device) to which a microscale pixel array is coupled. The size of the pixels that make up the luminescent array of such an imager device is typically in the range of about 5-20 micrometers, and the typical luminescent surface area of the device is about 15-150 square millimeters. .. Pixels in a luminescent microscale pixel array device can be individually addressed spatially, chromatically and temporally, typically by the drive circuitry of the CMOS chip. The brightness of the light produced by such an imager device can reach millions of cd / m ² at fairly low power consumption. An example of such a device is the QPI® imager (see Patent Documents 1-7) referred to in the exemplary embodiments described below. However, it should be understood that the QPI® imager is merely an example of the types of devices that can be used in the present invention. (“QPI” is a registered trademark of Ostendo Technologies, Inc.) Therefore, in the following description, any reference to the QPI® imager is a solid-state luminescent pixel array imager that can be used (hereafter. It should be understood that the purpose is merely to identify embodiments disclosed as one embodiment of "Imager") and not to any limitation of the present invention.

The present invention combines the inherent capabilities of the imager's luminescent micropixel array device as described above with a novel split-injection pupil HUD system architecture to facilitate cost and volume constraints, such as automotive HUDs. It realizes a low-cost, small-volume modular HUD (MHUD) system that can be used for. The combination of the luminescent high-intensity micro-emitter pixel array of an imager such as the QPI® imager and the split exit pupil HUD architecture of the present invention effectively operates even in high-intensity ambient sunlight. The HUD system can be small enough to fit behind dashboards or equipment panels of various vehicle sizes and types. (As used herein, the term "vehicle" is used in the most general sense and includes, but is not limited to, movement on land, on water, underwater, and in the air. Includes any means of movement.) Due to the low cost and modularity of the split-injection pupil HUD architecture feasible with such an imager, a modular HUD that can be adjusted to fit various vehicle volume constraints. The system can be realized. The advantages of the HUD system will become even more apparent from the detailed description provided herein in the context of the embodiments described in the following paragraphs.

FIG. 2 shows a design concept of a modular HUD (MHUD) system 200 according to an embodiment of the present invention. As shown in FIG. 2, in this preferred embodiment, the MHUD system 200 of the present invention is composed of an MHUD assembly 210 composed of a plurality of modules 215, and the modules 215 are integrally assembled to form an MHUD assembly 210. Thus, each module 215 comprises a single imager and associated optical system 220 and concave mirror 230. As shown in FIG. 2, the light emitted from each single imager with the associated optical system 220 is collimated, magnified and reflected by the associated concave mirror 230, and then partly on the front of the vehicle. Reflected away from the glass 240 to form a virtual image 260, which is visible within the eyebox segment 255 at the nominal head position of the vehicle driver. As shown in FIG. 2, each module 215 of the MHUD assembly 210 has the same virtual image 260 at any point in time from the vehicle windshield 240 in the same position, but in each corresponding eyebox segment 255. Arranged to form, the plurality of modules 215 of the MHUD assembly 210 together form the collective eyebox 250 of the MHUD system 200. That is, a part of the virtual image 260 is visible from each eyebox segment 255, and the whole is visible in the collective eyebox 250. Therefore, the overall size of the eyebox segment 255 of the MHUD system 200 can be adjusted by selecting an appropriate number of modules 215 constituting the MHUD assembly 210, the number of eyebox segments and modules being user-definable. It is a thing. Although each module 215 of the MHUD assembly 210 is arranged to form the same virtual image 260 at any point in time, these images will of course change over time, such as fuel gauge images. The MHUD system 200 of the present invention allows image data to be available at typical video rates, although it may change slowly or as quickly as in the display of the displayed image of a GPS navigation system. In some cases, it may operate at frequencies up to at least such rates.

In this preferred embodiment of the MHUD system 200, each eyebox segment 255 of module 215 of the MHUD assembly 210 is located at the exit pupil of the light bundle reflected by the corresponding concave mirror 230. The collective eyebox 250 of the MHUD system 200 is effectively one split exit pupil eyebox formed by the overlap of the eyebox segments 255 of the module 215 of the MHUD assembly 210. The method of designing this split exit pupil of the MHUD system 200 of the present invention will be described in more detail in the following paragraphs.

In this preferred embodiment of the MHUD system 200 of the present invention, the MHUD assembly 210 is composed of a plurality of modules 215, the modules 215 being integrally assembled to form an MHUD assembly 210, whereby each module 215 is a QPI ( A registered trademark) is composed of an imager such as an imager or another suitable light emitting structure such as an OLED device, and a related optical system 220 and a concave mirror 230. The design method of the MHUD assembly 210 of the MHUD system 200 of the present invention and each module 215 thereof will be described in more detail in the following paragraphs, but prior to that, the related advantages of the MHUD system 200 of the present invention and the related advantages. Describe the trade-offs of related design parameters.

Trade-offs of Optical Design Parameters for MHUD System 200 In order to understand the advantages of the MHUD system 200 of the present invention, the trade-offs of the underlying design of a typical HUD system and the related design parameters are described. It is considered important to do so. The virtual image generated by the HUD system is typically superimposed on a natural scene, which allows the viewer to steer the vehicle without the driver having to distract his sight and attention from the road or the vehicle's external environment. Visually recognizes the operating parameters of the vehicle and also provides important information such as navigation information. Important parameters to consider in the design of the HUD system include: the target size of the collective eyebox; the desired field of view (FOV); the size of the virtual image formed; the resolution of the virtual image; and the requirements for the volume of the system. The relationship between these design parameters and constraints is shown in FIG.

How the Modular HUD (MHUD) of the Invention Achieves Volume Reduction With reference to FIG. 3, the reduction in the size of the imager 220 of the MHUD system 200 leads to a smaller effective focal length (EFL), which leads to a smaller effective focal length (EFL). This is the characteristic optical track length of the system and generally contributes to the reduction of the volume of the system. However, if the size of the eyebox is maintained, reducing the size of the imager aperture leads to lower system F / #, which is accompanied by increased optical complexity. This generally results in a larger system volume. Regarding the design concept of the MHUD system 200 shown in FIG. 2, the size of the eyebox segment 255 for each module 215 is scaled with the size of the imager 220 to avoid an increase in optical complexity. This leads to the expansion and contraction of the volume of each module 215 depending on the size ratio of the imager 220. A plurality of modules 215 may be combined to form an MHUD assembly 210 capable of providing an arbitrarily sized collective eyebox 250. The novel design concept of the eye box divided into a plurality of segments of the MHUD system 200 of the present invention is realized by dividing the ejection pupil of the system formed in the viewer's eye box into a plurality of segments. Each segment corresponds to one of the eyebox segments 255 constituting the collective eyebox 250 of the MHUD system 200 of the present invention. Thus, such a split exit pupil design method of the MHUD system 200 of the present invention achieves a smaller overall volume aspect than a prior art HUD system that provides eyeboxes of the same size. This preferably leads to a reduction in the overall volume, complexity and cost of the HUD. Other advantages of the split exit pupil design method of the MHUD system 200 of the present invention disclosed herein will be described below. Not surprisingly, each module emits the same image at any point in time, so the vehicle operator is in the same position regardless of which one or more eyebox segments 255 the operator is looking at. You will see the same virtual image.

A major contributor to the volume of a prior art HUD system using a mirror reflector (Patent Documents 8-10) has been identified as a concave mirror. In addition to the large size of the mirror itself, the size of the image source also grows proportionally, which can be the use of large size imagers such as LCD panels, or the formation of large size intermediate images projected onto a diffuse screen. The latter adds a larger volume to incorporate the projector imager and its associated projection optics. As described above, the MHUD system 200 of the present invention is integrally assembled to form the reflector 235 as a whole of the MHUD assembly 210, which is extremely small in size and achieves a very small optical track length. By using the MHUD assembly 210, which consists of multiple modules 215 each with a relatively small size concave mirror 230, it is significantly compared to the prior art HUD system using a single concave mirror as the main reflector. Achieve a small volume aspect. The MHUD assembly 210 using an imager 220 with a small aperture allows the use of a concave mirror 230 with a small aperture, which has a small optical track length, which is a large volume of the present invention. It provides the MHUD system 200, which is small and efficient in terms of volume.

The design of the MHUD system 200 of the present invention works by splitting a large collimated beam, typically produced by a single large mirror, into three equally sized collimated subbeams in an exemplary embodiment. .. Each subbeam is generated by the optical subsystem of module 215. As a result, F / #, optical complexity, and focal length (EFL) (or optical track length) are reduced, resulting in a reduction in the physical volume envelope of the system. FIG. 4 shows an optical design aspect and a ray trace diagram of the module 215 constituting the MHUD assembly 210. As shown in FIG. 4, a module 215 of a preferred embodiment comprises one imager and associated optical system 220 and concave mirror 230. In the embodiment shown in FIG. 4, the optical system 420 associated with the imager 410 is shown as a separate lens optical element, whereas in one alternative embodiment of the invention, the optical system 420 associated with the imager is referred to as the imager 410. An integrated imager assembly 220 may be formed by mounting directly on top of the light emitting surface. As shown in FIG. 4, in each module 215, the reflective concave mirror 230 magnifies and collimates the image generated by the corresponding imager (or other imager) 220 into one eyebox of the collective eyebox 250. The optical element 420 associated with the imager 410 of FIG. 4 forms the segment 255, but balances the off-axis distortion and tilt aberration due to the reflective concave mirror 230.

FIG. 5 shows the optical performance of module 215 of MHUD assembly 210. As shown in FIG. 5, the role of the optical element 420 related to the imager 410 is to balance the off-axis distortion and tilt aberration caused by the reflective concave mirror 230 to provide a modulation transfer function (MTF). It is to minimize the swimming effect of the image while maintaining it at a sufficiently high level. For perfection, the swimming effect of an image is typically caused by a shift in the direction of light entering the viewer's eyes due to optical distortion caused by mirror aberrations, which is also caused by the viewer's head. As it moves around (or gazes at) the eyebox of the HUD system, it results in perceptible false movements (known as the "swimming effect") of the virtual image (Patent Document 6). In extreme cases, the excessive swimming effect of the virtual image is a motion sickness-like sensation, dizziness or nausea caused by a collision between the vestibular and eye movement aspects of the human visual and perceptual system. Since it may be connected (Non-Patent Documents 1 and 2), it is extremely important to minimize the swimming effect in the binocular optical system such as HUD.

Another advantage of the split exit pupil method of the MHUD system 200 of the present invention is that the above method significantly reduces the swimming effect as compared to the prior art HUD system using a single mirror with a large optical aperture. Is to achieve. The aberration of the small optical aperture of the reflective concave mirror 230 is much smaller than the aberration of the mirror with a relatively large optical aperture used in the conventional single mirror HUD system. Since the swimming effect is directly proportional to the magnitude of the optical distortion (or ray direction deflection) caused by the aberration caused by the HUD reflection mirror, the plurality of concave mirrors 230 having a small optical aperture of the MHUD system 200 of the present invention have conventionally been used. Achieves a significantly smaller swimming effect compared to the technology HUD system. Further, due to the angular overlap between the eyebox segments 255 of the MHUD module 215 (discussed in more detail in the description of FIG. 8), the perception of any point of the virtual image 260 provides an optical contribution from the plurality of MHUD modules 215. It will be incorporated. As a result, the optical distortion (or ray direction deflection) caused by the aberrations of the individual concave mirrors 230 of the multiple MHUD modules 215 tends to be averaged at any point in the virtual image 260, and as a result, The overall swimming effect perceived by the viewer of the MHUD system 200 is reduced.

In another embodiment of the invention, the imager 220 of the MHUD assembly 210 has a higher resolution than is possible for a human visual system (HVS), and this additional resolution is due to the concave mirror 230. Dedicated to digital image warping pre-compensation for residual optical distortion caused by aberrations. In a typical HUD viewing experience, virtual images are formed at a distance of approximately 2.5 m. The lateral visual acuity of the HVS is approximately 200 microradians. At such distances, the HVS can have a resolution of approximately 2500 x 0.0002 = 0.5 mm pixels, which corresponds to a resolution of approximately 450 x 250 pixels for a virtual image 260 with a 10-inch diagonal. do. The imager 220 used in the exemplary MHUD assembly 210 can provide a resolution much higher than this limit, such as a resolution of 640 x 360 pixels, or even a resolution of 1280 x 720 pixels, with an optical aperture of the same size. The imager 220, which provides higher resolution with an optical aperture of the same size, allows the use of a concave mirror 230 with an optical aperture of the same size, thus preserving the volume advantage of the MHUD assembly 200. The additional resolution of the imager 220 allows the use of digital image warping precompensation, which is concave while retaining the same advantages as described above in terms of maximum resolution and volume achievable in virtual image 260. The optical distortion due to the aberration of the mirror 230 and the resulting swimming effect are substantially eliminated.

Each reflective concave mirror 230 can be aspherical or free-form so that the aspherical or free-form factor of the concave mirror 230 has the optical aberrations of the concave mirror 230 and, if necessary, the curvature of the windshield. Selected to be the minimum. It should be noted that the position of each imager 220 is preferably axisymmetric with respect to the concave mirror 230 associated with them, thereby optimizing the balance of aberrations at any two adjacent edges of the concave mirror 230 ( It is guaranteed to be equal to some extent). This is an important aspect of the design of the MHUD system 200 of the present invention, as this guarantees a uniform viewing transition of the virtual image 260 between the plurality of eyebox segments 255 of the collective eyebox 250 of the MHUD system 200. be.

FIG. 6 shows a multi-view perspective view of the MHUD assembly 210. As shown in FIG. 6, the MHUD assembly 210 is composed of three reflective concave mirrors 230 integrally assembled within the enclosure 600. The three concave mirrors 230 can be manufactured separately and then integrated into the enclosure 600, or manufactured as a single component and then assembled into the enclosure 600. The three concave mirrors 230 may be made of embossed polycarbonate plastic, whether assembled separately or as a single optical component, the optical surface then using sputtering techniques. , Coated with a thin layer of reflective metal such as silver or aluminum. As shown in FIG. 6, the rear side wall of the enclosure is composed of three separate sections 610, each of which incorporates an optical window 615, the optical window 615 having a rear side wall section 610, each of which is a concave mirror 230. When assembled integrally with the mirror, it is aligned with the optical axis of each concave mirror 230. As shown in the side perspective view of FIG. 6, the upper edge portion 617 of each rear side wall section 610 is angled toward the concave mirror 230, whereby the angled edge portion surface of the rear side wall section 610. The imager 220 installed on the 617 can be aligned with the optical axis of each concave mirror 230.

As shown in the rear perspective view of FIG. 6, the rear side wall section 610 is integrally assembled on one side of the back plate 630, and the control and interface electronic device (printed circuit board) 620 of the MHUD assembly 210 is the back plate 630. It is installed on the opposite side of. Further, the back plate 630 also incorporates temperature cooling fins for dissipating the heat generated by the imager 220 of the MHUD assembly 210 and the interface electronic device element 620. As shown in the rear perspective view of FIG. 6, each imager 220 is installed on a flexible electronic board 618 that connects the imager 220 to a control and interface electronic device 620.

As shown in the rear perspective view of FIG. 6, a photodetector (PD) 640, typically a photodiode, is located in the center of the boundary edge of each pair of concave mirror 230 and rear sidewall section 610. May be incorporated, each photodetector 640 is positioned and oriented to detect the light emitted from the imager 220 to each concave mirror 230. Typically, three photodiodes are used in each module, one for each color of emitted light. The output of the photodetector (PD) 640 is connected to the control and interface electronics 620 of the MHUD assembly 210 and mounted within the hardware and software design elements of the interface electronics device element 620 (discussed below). Used as an input to the uniformity control loop. Also provided as an input to the control and interface electronics 620 of the MHUD assembly 210 is the output of the ambient photodetector sensor 660, which is typically an integrated component of the brightness control of the dashboard of most vehicles. ..

The control and interface device 620 of the MHUD assembly 210 incorporates the hardware and software design functional elements shown in the block diagram of FIG. 7, which include the MHUD interface function 710, control function 720, and uniformity. Includes loop function 730. Control and interface of the MHUD assembly 210 The MHUD interface function 710 of the electronic device 620 is typically implemented in a combination of hardware and software and is an image input 715 from the vehicle driver assistance system (DAS). To provide the image inputs 744, 745, 746 to the imager 220 of the MHUD assembly 210 after incorporating the color and brightness correction 735 provided by the control function 720 into this image. Although the same image input 715 may be provided for the three imagers 220 of the MHUD assembly 210, the MHUD interface function 710 may provide color and brightness specific to each imager 220 based on the color and luminance correction 735 received from the control function 720. Luminance correction is incorporated into the respective image inputs 744, 745, 746.

To ensure color and luminance uniformity across multiple segments 255 of the collective eyebox 250, the uniformity loop function 730 of the control and interface electronics 620 is the light detector of each module 215 of the MHUD assembly 210. PD) After receiving the input signals 754, 755, 756 from 640 and calculating the color and brightness associated with each module 215 of the MHUD assembly 210, the color and brightness will be more uniform across multiple segments 255 of the collective eyebox 250. Calculate the color and brightness corrections required to do this. This is achieved with the help of an initial calibration look-up table, which is performed and stored in the memory of the control and interface electronics 620 when the MHUD assembly 210 is first assembled. Next, the color and luminance correction calculated by the uniformity loop function 730 is provided to the control function 720, and the control function 720 receives these corrections from the ambient light sensor 650 as well as the external color and luminance adjustment input command. Combined with 725, a color and luminance correction 735 is generated, which is subsequently incorporated into the image data by the MHUD interface function 710, and then the corrected image data is used as image inputs 744, 745, 746 in the imager 220. Provided. In incorporating the input received from the ambient light sensor 650 into the color and brightness correction, the control function 720 is a virtual heads-up display in proportion to or in relation to the brightness of the vehicle's external light. Adjust the brightness of the image. It should be noted that the "image data" used herein may be received as input to a heads-up display, provided to an imager, or in any other form. However, it means any format of image information.

As mentioned above, one embodiment of the MHUD system 200 uses an imager 220 having a resolution higher than the maximum resolution the HVS can have in the virtual image 260 and also digitally warping the image input to the imager 220. Incorporate measures to eliminate or significantly reduce the optical distortion and swimming effects caused by. The MHUD interface function 710 of the MHUD assembly 210 of the MHUD system 200 of the embodiment contains a plurality of data identifying data identifying digital image warping parameters required for pre-compensating for residual optical distortion of each concave mirror 230. Look-up tables may also be built-in. These parameters are used by the MHUD interface function 710 to warp the digital image input of each imager 220 so that the image data to each imager 220 pre-compensates for the residual distortion of the corresponding concave mirror 230. The digital image warping parameters incorporated in the look-up table of the MHUD interface function 710 are pre-generated by the optical design simulation of the MHUD assembly 210, and then each after the digital image warping pre-compensation is applied by the MHUD interface function 710. It is reinforced by optical test data based on the measurement of residual optical strain in module 215. The resulting digitally warped data is then combined with the color and luminance correction 735 provided by the control function 720 to MHUD assembly the image data with color and luminance correction and distortion pre-compensation. It is provided as image inputs 744, 745, 746 to the imager 220 of 210. Such a design method of the MHUD system 200 can significantly reduce or completely eliminate the residual optical distortion caused by the concave mirror 230 and the resulting swimming effect, thereby realizing a distortion-free MHUD system 200.

As shown in the perspective view of FIG. 6, the upper side of the MHUD assembly 210 is a glass cover 430, which serves as an optical interface window of the MHUD assembly 210 on the upper surface of the dashboard of the vehicle and by sunlight in the imager 220. It functions as a filter that attenuates the infrared emission of sunlight to prevent heat load. The glass used should also be selected to have significant transmission to the wavelength of the light of interest.

The design method of the MHUD assembly 210 takes advantage of the features of the human vision system (HVS) to simplify the design implementation and assembly tolerance of the MHUD assembly 210. First, due to the diameter of the pupil of the eye being approximately 5 mm (3-5 mm during the day, 4-9 mm at night) and the resulting lateral visual acuity when viewing the virtual image 260, the MHUD assembly 210 Indistinguishable small gaps are allowed between the concave mirrors 230, which can reach as wide as 1 mm. Second, the eye angle difference adjustment limit of approximately 0.5 ° allows a small angular tilt between the concave mirrors 230 of the MHUD assembly 210, which can reach approximately 0.15 °. .. This allowance for tilts and gaps greatly eases the requirement for mechanical alignment tolerances for the concave mirror 230 of the MHUD assembly 210, thus making it extremely cost effective for the MHUD assembly 210. An assembly approach can be realized. Any further tilt and / or alignment requirements are usually readily addressed by software.

FIG. 8 shows a novel split eyebox design for the MHUD system 200 of the present invention. The figure of FIG. 8 is intended to show the relationship between the collective eyebox 250 of the MHUD system 200 and the virtual image 260. FIG. 8 also shows an exemplary object 810 (arrow shown on the virtual image 260) displayed by the MHUD system 200. In the design of the MHUD system 200, each eyebox segment 255 will typically be positioned at the exit pupil of its respective module 215. As a result, the image information presented to the viewer's eyes within each eyebox segment 255 is within that angular space. Thus, the arrow-shaped object 810 of the virtual image 260, which is divided within each eyebox segment 255 and presented to the viewer, typically has the viewer's head positioned within the central region of each eyebox segment 255. When it is, it becomes completely visible to the viewer, but as the viewer's head moves to the right or left of the eyebox segment 255, the tip or tail of the arrow-shaped object 810 of the virtual image 260 gradually becomes It will be blurred (or disappear). In the design of the MHUD system 200, when the modules 215 are integrated into the MHUD assembly 210 as shown in the perspective view of FIG. 6, the eyebox segments 255 of the modules 215 are overlapped as shown in FIG. As a result, the collective eyebox 250 of the MHUD system 200 is generated. Thus, the collective eyebox 250 of the MHUD system 200 is formed by overlapping exit pupil areas forming the eyebox segments 255 of the plurality of modules 215 and is therefore presented to the viewer's eye within the collective eyebox 250. The image information is an angle-multiplexed view of the virtual image 260 that extends over the composite angle field of view of the MHUD module 215. As shown in FIG. 8, the arrow-shaped object 810 of the virtual image 260 becomes completely visible (or viewable) within the overlapping area of the eyebox segments 255 defining the collective eyebox 250 of the MHUD system 200. The arrow-shaped object 810 of the virtual image 260 gradually blurs (or disappears) as the viewer's head moves to the right or left side of the peripheral region of the collective eyebox 250.

The size of the overlap between the eyebox segments 255 of the module 215 depends on their angular blur profile (820 in FIG. 8) and determines the final size of the collective eyebox 250 of the MHUD system 200. The latter is defined therein as the area boundaries or dimensions of the collective eyebox 250 in which the virtual image 260 is fully visible (or viewable) with the desired luminance uniformity. FIG. 8 also shows the shielding of the resulting angular blur profile of the MHUD assembly 210 over the entire area of the overlapping eyebox segments 255 of the module 215. As shown in FIG. 8, the luminance of the virtual image 260 perceived by the viewer includes the luminance contributing components Λ _R , Λ _C , Λ _L (left, center, right) from each module 215. The criterion for defining the boundaries of the aggregate eyebox 250 is that the brightness of the virtual image 260 is uniform within a given threshold λ (eg, less than 25%) over the selected region of the eyebox segment 255. Area A of overlap, i.e., Var _A (Λ _R + Λ _C + Λ _L ) ≤ λ (desired uniformity threshold). Due to the above criteria defining the boundaries of the collective eyebox 250 shown in FIG. 8 and the overlap of the eyebox segments 255 of the module 215, the perceived brightness across the virtual image 260 is at least 50 from one of the modules 215. Includes% contributing component. This means that each module 215 provides at least 50% of the perceived brightness of the virtual image 260 at any location within the boundaries of the collective eyebox 250 defined by the criteria above. When using this design approach of the MHUD system 200, the desired luminance uniformity of the virtual image 260 is the basis for defining the size of the collective eyebox 250. This design criterion is shown in the design example of FIG. 8 using a uniformity threshold λ = 25% for forming a 120 mm wide collective eyebox 250. As shown in FIG. 8, using the uniformity threshold λ = 37.5%, an approximately 25% wide collective eyebox 250, measured at approximately 150 mm, is defined.

As shown in FIG. 8, in the area of the eyebox segment extending beyond the right and left sides of the collective eyebox 250 of the MHUD system 200, the arrow-shaped object 810 of the virtual image has the viewer's head in each of these. As you move into the area, it gradually blurs or disappears. Using the above design approach of the MHUD system 200, the collective eyebox 250 of the MHUD system 200 defined by the design criteria defined above by adding the module 215 to the right or left side of the MHUD assembly 210 shown in FIG. The lateral width is extended to the right or left, respectively, which makes the arrow-shaped object 810 of the virtual image 260 completely visible with the desired brightness uniformity. If a row of another module 215 is added to the MHUD assembly 210, the same effect of extending the height of the collective eyebox 250 will occur in the orthogonal direction. Thus, using such a modular design method of the MHUD system 200 of the present invention, by adding an additional module 215 to the MHUD assembly 210, any width and height dimension selected by the design will eventually be present. It is possible to realize a collective eye box 250 of any size.

In essence, the split exit pupil modular design method of the MHUD system 200 of the present invention allows the use of multiple imagers 220 and concave mirrors 230, each with a relatively small aperture and each short optical track. Achieving length replaces the extremely long optical track lengths and single mirrors of long image sources used in prior art HUD systems. Thus, the combination of the MHUD module 215 with a smaller aperture 220 and a concave mirror 230 achieves a prior art HUD system using a larger single image source and a single mirror to obtain an eyebox of the same size. You can achieve a volumetric aspect that is significantly smaller than you can. Further, the size of the collective eyebox 250 of the MHUD system 200 achieved can be adjusted by using an appropriate number of modules 215 (basic design elements). Conversely, the volume aspect of the MHUD system 200 is larger than what is achievable by a prior art HUD system that can fit the same available volume while adapting to the volume available in the vehicle's dashboard area. Can achieve the collective eyebox 250 of.

To illustrate the above advantages with respect to the volume of the MHUD system 200 of the present invention, the perspective view of FIG. 6 shows three imagers 220 having an optical aperture size of 6.4 × 3.6 mm and an optical aperture size of 60 each. The design dimensions of the MHUD assembly 210 are shown to achieve the size of a 120 × 60 mm collective eyebox 250 based on a luminance uniformity threshold λ = 25% with three concave mirrors of × 100 mm. Based on the design dimensions shown in FIG. 6, the total volume of the MHUD assembly 210 is approximately 1350 cc (1.35 liters). For comparison purposes, the total volume of a prior art HUD system using a single mirror with a larger aperture and a single larger image source to achieve the same eyebox size is 5000 cc ( 5 liters) or more. Therefore, by the above-mentioned design method of the MHUD system 200 of the present invention, it is possible to realize a HUD system having a volume efficiency 3.7 times higher (that is, 3.7 times smaller) than the conventional HUD system. To visualize this volume advantage, FIG. 9 shows the volume of a design example of the MHUD assembly 210 shown in FIG. 6 installed on the dashboard of a quasi-small vehicle. As shown in FIG. 9, the volume-efficient design of the MHUD system 200 of the present invention adds HUD functionality to the extremely limited dashboard volume where prior art HUD systems cannot be easily fitted. can.

FIG. 10 shows the ray path of the MHUD system 200. As shown in FIG. 10, and as already described and illustrated in FIG. 2, the three imagers 220 constituting the MHUD assembly 210 each have the same image of the same resolution (eg, 640 × 360 pixels) as three images. After reflection by each of the three concave mirrors 230, the entire 120 × 60 mm collective eyebox 250 of the above design example is angularly addressed and over the 125 × 225 mm virtual image 260 of the above design example. , 640 × 360 pixels spatial resolution.

FIG. 10 shows the design requirements for generating a luminance of 10,000 cd / m2 in the virtual image 260. With a typical windshield reflectance of approximately 20% and the above-mentioned boundary demarcation criteria for the collective eyebox 250, each of the three imagers 220 will produce a brightness of approximately 25,000 cd / m 2. To conservatively estimate, the three imagers 220 of the MHUD assembly 210 and the control and interface electronics 620 consume approximately 2W in total to produce a brightness of 25,000 cd / m2. It accounts for approximately 25% of the power consumption of the prior art HUD system.

Referring to the performance of the MHUD system 200 shown in FIG. 5, the enclosed energy plot of FIG. 5 is a geometry of the collimated light beam from the optical aperture (size 180 micrometers) of the concave mirror 230. Indicates the target blur radius. Using the design example of each module 215 shown in FIG. 6 with an effective focal length of 72 mm, the blur size at 180 micrometers shown in the enclosed energy plot of FIG. 5 is the imager on each module 215. It provides an angular length of 0.143 ° with respect to the light beam emitted from a pixel of 220 and collimated by the corresponding concave mirror 230. The swimming effect is associated with an angular spread of 0.143 ° from one pixel to the entire beam width, while the resolution (MTF) is determined by the effective beam width sampled by the size of the pupil of the eye. The MTF plot of FIG. 5 shows the MTF of each module 215 calculated for a typical eye pupil aperture with a diameter of 4 mm. The smaller the angle of this angular spread, the smaller the swimming radius in the virtual image 260. For the virtual image 260 viewed at 2.5 m from the collective eyebox 250 of the MHUD system 200, the corresponding swimming radius for the design example of the MHUD system 200 is 6.2 mm. Using a single mirror and having an optical aperture size equal to the overall size of the aperture of the MHUD assembly 210 design example, the prior art HUD system has an optical aperture that is approximately 2.4 times larger than the optical aperture of module 215. Have. Since the aberration blur size is directly proportional to the cube of the aperture size (Non-Patent Document 3), a prior art single mirror HUD system having an optical aperture size equal to the size of the entire aperture of the design example of the MHUD assembly 210 is 5. If the order aberration accidentally compensates for a large third order aberration (which is not intentionally achieved by design), it has a corresponding swimming radius of approximately 14.3 mm, otherwise the prior art. The single mirror HUD system typically has a corresponding swimming radius of approximately 39.7 mm, which is 6.2 times larger than the swimming radius achieved by the design example of the MHUD system 200. Also, using the aberration precompensation method described above, the swimming radius of the MHUD system 200 can be significantly reduced or even eliminated altogether as specified for this design example.

FIG. 10 also shows the ray path of the MHUD system 200, including the load of sunlight. As shown in FIG. 10, the reverse light path of sunlight hitting the windshield of the vehicle reaches the area of the collective eyebox 250 and in some cases causes glare in the virtual image 260. In the design of the MHUD system 200 of the present invention, the amount of sunlight that can reach the collective eyebox 250 is significantly smaller than that of the conventional HUD system. First, assuming that the windshield 240 has a light transmittance of 80%, the light rays from the sun are attenuated by the windshield 240 up to 80% of its brightness. Second, the sun's rays transmitted through the windshield 240 and reflected by one of the concave mirrors 230 towards the corresponding imager 220 are anti-reflective (AR) of the optical aperture of the imager 220. The coating attenuates up to 5% of its brightness and then reflects back towards the assembly of the concave mirror 230. Third, this reverse path of sunlight is attenuated by up to 20% of its brightness as it is reflected by the windshield 240 towards the collective eyebox 250. As described above, since the imager 220 and the concave mirror 230 of each module 215 contribute up to 50% to the brightness of the virtual image 260, the sunlight glare reflected from the module 215 exposed to sunlight is generated in the virtual image 260. It will appear to be further attenuated by 50%.

Therefore, based on this path attenuation analysis, sunlight reaching the collective eyebox 250 is attenuated up to 0.4% of its brightness (much less than 1%). The MHUD system 200 is capable of producing a brightness of 10,000 cd / m2 and 0.4% sunlight glare in the virtual image 260, allowing the MHUD system 200 to tolerate a brightness of more than 250,000 cd / m2. Equal to approximately 28 dB of unified glare ratting (UGR) (or glare-to-image intensity ratio). It should be mentioned that while the glass cover 430 is infrared absorbent, it is transparent to the wavelengths of light used in the heads-up displays of the invention, which allows heat from the load of sunlight to be dissipated. The concave mirror 230 assembly prevents it from being returned to the imager 220 and concentrating.

In the above-described embodiment, a plurality of modules are arranged side by side to provide overlap of eyebox segments, thereby providing an aggregate eyebox 250 that is wider than the eyebox segment 255 itself. However, if desired, the modules are also arranged so that the eyebox segments of the module 215 are laminated to provide a taller collective eyebox 250, instead of or in addition to the above. Often, again, all modules display the same virtual image in the same position in front of the vehicle. It should be noted that the stacking to provide a taller collective eyebox 250 is generally not a stacking of modules, but a stacking of eyebox segments simply because of additional modules because of the typical windshield tilt. This may be achieved by using a large, substantially horizontal area of the dashboard.

Also, "as shown in FIG. 2, the light emitted from each single imager with the associated optical system 220 is partially collimated, magnified and reflected by the associated concave mirror 230 and then partially. Reflected away from the vehicle front glass 240 to form a virtual image 260, which is visible within the eyebox segment 255 at the nominal head position of the vehicle driver. " However, in any embodiment, the degree of collimation achieved by the concave mirror is not always perfect and is intentional to limit how far forward the virtual image will be formed in the vehicle. May be set to. In some examples, by deliberately designing the concave mirror to actually distort the collimation, this is the most prominent example of any subsequent source of aberration (if windshield curvature is present). ) May be offset.

It has already been shown that off-axis distortion and tilt aberration, as well as color and luminance correction, can be performed in the control and interface electronics 620 of the MHUD assembly 210 of FIG. 2 (see also FIG. 6). Of course, lateral position correction of each image or image segment from each module 215 may also be performed (or mechanically) in the control and interface electronics 620, thereby double image or double. The image part disappears. Further, it should be noted that there are at least two main aspects of "brightness correction". The first and most prominent aspect is the correction of luminance variations between modules, which prevents the luminance (and color) of images from different modules from being different. However, related to this is the fact that image warping and other factors can in some cases cause brightness variations in multiple image portions within individual modules, where warping changes in pixel spacing. , Can cause visible luminance aberrations. When this happens, the brightness of the individual pixels in each module can be controlled individually, so if necessary, the pixel brightness is locally increased in areas where pixel separation increases, resulting in pixel separation. In the area of decrease, the brightness of the pixel can be reduced locally. Finally, note that a typical solid-state luminescent pixel array imager is not a square imager, but typically a rectangle with unequal dimensions. As a result, the choice of imager orientation can also provide additional variables that can be used in the design of the heads-up displays of the present invention.

Table 1 below shows the salient performance characteristics of the imager-based MHUD system 200 of a particular embodiment of the invention, which uses a single larger mirror and a single larger image source. Illustrates the performance advantages of certain embodiments of the invention as compared to prior art HUD systems. As shown in Table 1, the split exit pupil MHUD system of the present invention is many times superior to the conventional HUD system in all performance categories. In addition, due to the relaxed manufacturing tolerance and the smaller size of the mirror, as mentioned above, the MHUD system 200 of the present invention is much more cost effective than prior art with comparable eyebox sizes. Expected to be higher.

Multi-image head-up display system using near-field and far-field virtual images In many HUD system applications, the HUD system allows viewers to view multiple virtual images, preferably additional information, safely. It is desirable to display it in front of the viewer so as not to distract the viewer's attention from driving while providing the possibility. In this context, a plurality of virtual images may be displayed by the HUD system, where, for example, a first virtual image is displayed at a distance in the far field typically adopted by conventional HUD systems and a second. Display the virtual image of. Preferably, both of these virtual images are viewable to the viewer of the HUD system without having to keep his head away from the road and to keep paying attention to driving conditions.

In one preferred alternative embodiment of the invention of the present disclosure, the split exit pupil design architecture described above may be used with a plurality of display elements 220 (ie, an imager and associated optical system 220), as shown in FIG. , Each display element 220 is configured to modulate multiple images with different output angles.

In one aspect of the multi-image heads-up display system of the present invention, the system may include a plurality of modules 215, each module 215 being: a solid-state luminescent pixel array imager (ie, a display element) 220; and a solid-state luminescent. The first and second virtual images that can be viewed within the eyebox segment by collimating, magnifying, and reflecting the first and second images generated by the sex pixel array imager 220 toward the vehicle's windshield. It has a concave mirror 230 configured to form an image. Multiple modules are combined so that the heads-up display is provided as having a larger collective eyebox 250 than the eyebox segment 255 of each module 215, and the collective eyebox 250 is a vehicle. It is placed so that it is in the nominal head position of the driver. In this first aspect of the multi-image head-up display system of the present invention, the solid state luminescent pixel array imager 220 has a set of first pixels associated with each set of first micro optics and a second set of pixels. It comprises a second set of pixels associated with each set of micro-optics. The first set of micro optics is configured to orient the outputs from each of the first set of pixels to produce the first image described above, thereby the first distance from the collective eyebox 250. A first virtual image that can be viewed is generated in. The second set of micro optics is configured to orient the outputs from each of the second set of pixels to produce the second image described above, thereby providing a second distance from the collective eyebox 250. A second virtual image that can be viewed is generated in. The micro optics may include non-telecentric lenses or non-telecentric optics configured to provide an overall tilted pixel output with respect to the surface of the solid-state luminescent pixel array imager 220.

In the first aspect of the embodiment of the multi-image head-up display system of the present invention, the first distance may be a distance in a far field of view, and the second distance may be a distance in a short field of view. .. The first set of pixels may be the set of user-defined first pixels of the solid-state luminescent pixel array imager 220, and the second set of pixels may be the set of solid-state luminescent pixel array imager 220. , May be a second set of user-defined pixels. The first set of pixels may be odd-row pixels of the solid-state luminescent pixel array imager 220, and the second set of pixels may be even-row pixels of the solid-state luminescent pixel array imager 220. good. The first set of pixels may be even rows of pixels in the solid state luminescent pixel array imager 22 and the second set of pixels may be odd rows of pixels in the solid state luminescent pixel array imager 220. good. The first set of pixels may be pixels that make up at least 50% of the pixel area of the solid-state luminescent pixel array imager 22, and the second set of pixels may be the above-mentioned solid-state luminescent pixel array imager 220. It may be the rest of the pixel area. The first set of pixels may be the upper region or upper portion of the solid state luminescent pixel array imager 220, and the second set of pixels may be the lower region or lower portion of the solid state luminescent pixel array imager 220. It may be a part.

11A-B, 11C-D show a non-limiting example of such a multi-image optical modulation display element 220, which is a predetermined pixel row or pixel in a 2D array of pixels on the display element 220. A given set of individual pixels, such as a set of rows, is configured by incorporating micro-optics that orient or modulate the light emitted from each pixel in a given unique direction.

11A-B and 11C-D are examples in which the multi-image display element 220 is designed to modulate two images simultaneously and the first and second images are emitted from the surface of the display element 220 in different directions, respectively. show. When such a display element 220 is used in the context of the split exit pupil HUD design architecture of FIG. 2, the first image modulated (above) is a far-field distance (eg, from the eyebox 250 of the HUD system). Generates a first virtual image that can be viewed at a distance of approximately 2.5 m), while the modulated second image is a second virtual image that can be viewed at a short field distance (eg, approximately 0.5 m). Generate an image. These two viewable virtual images can be simultaneously modulated by a multi-image split exit pupil HUD system, and the viewer of this HUD system can view the line of sight in a plane of vertical axis and multiple displays of the split exit pupil HUD system. The first virtual image or the second virtual image can be selectively viewed only by reorienting the elements 220 by an angle proportional to the angle inclination (or separation) of the modulation directions of the two modulated images.

11A and 11B show a top view and a side view of the display element 220 according to an embodiment of the present invention, in which the plurality of display elements 220 of the split ejection pupil HUD system have two optical apertures thereof. Divide a group of display pixels into, for example, odd-row and even-row display pixels (so that a group of one pixel, i.e. an odd-row pixel, modulates the first image and a second group of pixels, i.e. even. The pixels in the row modulate the second image), thereby being configured to modulate the first and second images. Such directional modulation capability of the display element 220 of the HUD system is such that the micro-optical or micro-lens element associated with each image modulation pixel group is directionally modulated with light emitted from the associated pixel in a given image direction. It can be realized by designing to. For example, in the case shown in FIGS. 11A, 11B, the micro-optics associated with the pixels in the odd rows form the first image by orienting the light emitted from the group of pixels involved. On the other hand, the micro-optics associated with even rows of pixels form a second image by orienting the light emitted from a group of associated pixels. Although the light rays are shown as parallel to each of the images in FIGS. 11A to 11D, the light rays actually spread from the imager 220 in a fan shape as a whole, whereby the size of the image can be expanded as necessary. Or it will be expanded. Pixel emission angles can be achieved by using a non-telecentric micro-optical lens element in the form of a non-telecentric QPI® imager, as described in more detail below.

When using the above-mentioned single image split exit pupil HUD design architecture, the plurality of imagers 220 modulate the same two images in different directions in the collective eye box 250 of the split exit pupil HUD system. Both virtual images are presented here, and the resulting two modulated virtual images are each viewable across the collective eyebox 250, but in different vertical (or orientation) directions.

In the additional multi-image HUD system shown in FIGS. 11C, 11D, the plurality of display elements 220 of the split exit pupil multi-image HUD system are each in two regions or areas of pixels, i.e., in the illustrated example, of pixels. It has an optical aperture that is divided into an upper area and a lower area of the pixel. In this embodiment, each of the two images modulated in different directions is modulated by a single dedicated pixel area. For example, as shown in FIGS. 11C, 11D, the upper region of the pixels of the optical aperture of the display element 220, which may be any user-defined portion of the imager's set of pixels, constitutes the upper region of the pixels. The display element has a micro-optical element designed to orient the light emitted from each pixel of the display element 220 to form a first image as defined above, while the display element. The lower region of the pixel of the 220 optical aperture orients the light emitted from each pixel of the display element 220 that constitutes the lower region of the pixel to produce a second image as defined above. It has a micro-optical element designed to form. Pixel emission angles can be provided by the use of non-telecentric micro optics in the form of a non-telecentric imager 220, as described in more detail below.

FIG. 12 shows a preferred embodiment of the multi-image segmented exit pupil HUD system of the present invention. As shown in FIG. 12, each of the plurality of display elements (or imagers) 220 may modulate two virtual images, where the first image is modulated upwards and the second image is modulated downwards. Will be done.

The plurality of display elements 220 simultaneously modulate both the first and second images to angularly fill the multi-image segment exit pupil HUD system eyebox 250, as shown in FIG. After being collimated by the concave mirror 230 and reflected by the windshield to the eyebox 250, the collimated ray bundles constituting the first and second images modulated (generated) by the plurality of display elements 220 , Allows viewing at two different tilt angles within the eyebox 250, allowing viewers of the multi-image split exit pupil HUD system to focus on two individually and simultaneously modulated virtual images. The first virtual image is viewable in the far field 260-1 and the second virtual image is viewable in the near field 260-2, whereby the two virtual images are viewed by the plurality of display elements 220. Only an angle 220-3 proportional to the directional separation angle 220-4 between the two modulated images is angularly separated in the vertical (azimuth) direction.

These two virtual images are at different first and second virtual distances because their ray flux is collimated at different levels (to different degrees). The collimation of the concave mirror 230 is designed to achieve the distance of the far-field virtual image from the eyebox 250. The non-telecentric QPI® imager micro-optics described below as specific examples of specific embodiments further collimate the light emitted from each pixel associated with the non-telecentric QPI® element. Designed to be introduced. Thus, the complex collimation achieved by the non-telecentric micro-optics in cooperation with the concave mirror 230 achieves a far-field virtual image distance and a near-field virtual image distance from the eyebox 250, thereby multi-image HUD. Can display both the far-field virtual image and the near-field virtual image at the same time.

As shown in FIG. 13, the viewer of the multi-image split exit pupil HUD system simply reorients the line of sight by an angle 220-3 in the vertical (azimuth) direction, and the first and second are modulated by the HUD system. You can view (or focus on) one of the two virtual images (see also Figure 12). Since these two virtual images are independently and separately modulated by two separate groups of pixels that make up the display element (imager) 220, the first and second images displayed to the viewer are, respectively. , Can contain different information that may be of interest to the viewer.

FIG. 13 also shows the nominal positions of the first and second virtual images modulated by the multi-image segment exit pupil HUD system, where the viewer is illustrated in the far-field virtual image. In a non-limiting example, it is possible to focus at a distance of approximately 2.5 m (approximately at the edge of the vehicle's windshield), and for near-field virtual images, the viewer is at a distance of approximately 0.5 m. Focus can be achieved (approximately at the outer lower edge of the vehicle's windshield).

It should be noted that the above-mentioned ability to handle multiple images of the HUD beneficially does not result in an increase in volume aspects of the multi-image segmented exit pupil HUD system outlined in FIG. The interface 710, control function 720 and uniformity loop 730 of the display element (imager) 220 also remain invariant as shown in FIG.

The main differences in the implementation and design method of the multi-image split exit pupil HUD system compared to the single image split exit pupil HUD system described are as follows:
1. 1. As described in the above embodiments, the plurality of display elements (imagers) 220 have the ability to modulate the plurality of images in different directions.
2. 2. The vertical field of view (FOV) of a multi-image split exit pupil HUD system is angularly split into two directional regions so that two angularly separated images can be modulated simultaneously.
3. 3. The image input 715 to the plurality of display elements (imagers) 220 is composed of two images, each (digitally) addressed to the corresponding pixel group described in the above embodiment.

FIG. 14 shows an exemplary embodiment of the non-telecentric QP imager referenced above, wherein the non-telecentric micro-optical element 1250-1 can be realized as a refractive optical element (ROE) and is used therein. The optical output of the selected pixel can be oriented at an overall tilted angle with respect to the surface of the display element 220 to provide a near-field virtual image.

In the embodiment of FIG. 14, the directional modulation aspect of the pixel-level refracting non-telecentric micro-optical element 1250-1 is an eccentric microlens 1250 formed by a continuous layer of dielectric materials 1310, 1320 with different refractive indexes. It can be realized by using -1. FIG. 14 is a schematic cross-sectional view of a display element 220 including a plurality of non-telecentric refraction micro-optical elements 1250-1. In this embodiment, the array of pixel-level non-telecentric microoptics 1250-1 uses semiconductor lithography, etching, and deposition techniques for silicon oxide for the low index layer 1310 and for the high index layer 1320. It may be monolithically manufactured at the wafer level as a plurality of layers of a semiconductor dielectric material such as silicon nitride. As shown in FIG. 14, the array of pixel-level micro-optics 1250-1 was continuously (sequentially) deposited to form multiple layers, i.e., the refractive surface of the pixel-level micro-optics 1250-1. Realized using dielectric materials 1310, 1320 with different refractive indexes, the optics are refracted micro over the microlens array as needed to obtain the desired non-telecentricity and image projection direction. The center position of the lens element changes gradually.

FIG. 15 shows another exemplary embodiment of the non-telecentric QPI® imager referenced above, wherein the non-telecentric micro-optical element 1250-2 is implemented as an inclined dioptric element (ROE). Also, if necessary, it gradually changes across the microlens array to obtain the desired non-telecentricity and image projection direction, which can also be used to reduce the optical output of the selected pixel. A near-field image or a second image can be provided by orienting at an overall tilted angle with respect to the surface of the imager 220. In this embodiment, the directional modulation aspect of the pixel-level refracting non-telecentric micro-optical element 1250-2 is an inclined microlens 1250-2 formed by a continuous layer of dielectric materials 1410, 1420 with different refractive indexes. Can be realized using.

FIG. 15 is a side view of the display element 220 including a plurality of tilted refraction micro-optical elements 1250-2. In this embodiment, the array of pixel-level non-telecentric microoptical elements 1250-2 uses semiconductor lithography, etching, and deposition techniques to make silicon oxide for the low index layer 1410 and for the high index layer 1420. It may be monolithically manufactured at the wafer level as a plurality of layers of a semiconductor dielectric material such as silicon nitride. As shown in FIG. 15, the array of pixel-level non-telecentric micro-optics 1250-2 is continuous (sequentially) to form multiple layers, i.e., the refractive surface of the pixel-level non-telecentric micro-optics 1250-2. ) It can be realized by using the deposited dielectric materials 1410 and 1420 having different refractive indexes.

As described above, the present invention has a number of embodiments, which may be carried out alone or in various combinations or partial combinations as desired. Although the specific preferred embodiments of the present invention have been disclosed and described for purposes of illustration rather than limitation, those skilled in the art will not deviate from the spirit and scope of the invention as defined by the entire scope of the following claims. It will be appreciated that various changes in form and detail can be made to the above embodiments.

Claims (9)

A head-up display for vehicles
The head-up display is:
It has multiple modules, each of which is:
Solid-state luminescent pixel array imager;
The first and second images generated by the solid-state luminescent pixel array imager are collimated, magnified, reflected towards the windshield of the vehicle, and viewed within the eyebox segment. It has a concave mirror arranged to form an image and a second virtual image,
The plurality of modules are arranged by combining the eyebox segments to provide the head-up display having a larger collective eyebox than the eyebox segment of each module, wherein the collective eyebox is of the vehicle. Located in the driver's nominal head position;
The solid-state luminescent pixel array imager has a set of first pixels associated with each set of first micro-optics and a set of second pixels associated with each set of second micro-optics. Preparation;
The set of first micro-optics is configured to project images from each set of first pixels outward from the surface of the solid-state luminescent pixel array imager, thereby said. The first virtual image that can be viewed at a first distance from the collective eyebox is generated;
The set of second micro-optics is configured to project an image from each set of second pixels in a direction tilted downward with respect to the first image, thereby the collective eye. A heads-up display that produces the second virtual image that can be viewed at a second distance from the box. The first distance is a distance in a distant field of view.
The head-up display according to claim 1, wherein the second distance is a short-field distance. The first set of pixels comprises a set of user-defined first pixels of the solid-state luminescent pixel array imager.
The heads-up display of claim 1, wherein the second set of pixels comprises a set of user-defined second pixels of the solid-state luminescent pixel array imager. The first set of pixels consists of odd rows of pixels in the solid-state luminescent pixel array imager.
The heads-up display of claim 1, wherein the second set of pixels comprises even rows of pixels of the solid-state luminescent pixel array imager. The first set of pixels is composed of even rows of pixels of the solid state luminescent pixel array imager, and the second set of pixels is composed of odd rows of pixels of the solid state luminescent pixel array imager. The head-up display according to claim 1. The first set of pixels is composed of the pixels that make up at least 50% of the pixel area of the solid-state luminescent pixel array imager.
The heads-up display of claim 1, wherein the second set of pixels comprises the remaining pixel area of the solid-state luminescent pixel array imager. The first set of pixels consists of the upper region of the solid-state luminescent pixel array imager.
The heads-up display of claim 1, wherein the second set of pixels comprises a lower region of the solid-state luminescent pixel array imager. The head-up display according to claim 1, wherein the number of the eyebox segment and the module is a user-defined number of the eyebox segment and the module. The first set of pixels comprises a set of user-defined first pixels of the solid-state luminescent pixel array imager.
The second set of pixels comprises a set of user-defined second pixels of the solid-state luminescent pixel array imager.
The head-up display according to claim 1, wherein the number of the eyebox segment and the module is a user-defined number of the eyebox segment and the module.

Images