JP7114146B2 - DISPLAY DEVICE AND AUTOMOBILE HEAD-UP DISPLAY SYSTEM USING THE SAME - Google Patents

Description

The present invention relates to a display device and a vehicle head-up display system using the same, in particular a display device that uses a single image generation unit to generate multiple virtual images at different distances. and an automotive head-up display system using the same.

While driving, the driver looks away from the road and looks at the instrument panel and other consumer electronics, which is a safety concern. Therefore, an important means of transferring driving information on the instrument panel to a head-up display (HUD) is utilized for safe driving.

With the development of HUD, the additional functions are becoming more and more abundant, and now there are new application requirements such as augmented reality HUD (AR-HUD). In addition, it requires multiple virtual image planes. As a result, information such as a navigator and a map can be displayed on a distant virtual image plane, and information such as vehicle speed and oil amount can be displayed on a nearby virtual image plane. FIG. 1 is a conceptual diagram of a HUD having a plurality of virtual image planes, as shown in FIG. have In the existing technology, to realize HUD with multiple virtual image planes, most of them adopt the following two methods: (1) using two image generation units and two sets of projection optical systems; For example, one set of image generation unit and projection optical system is mounted under the instrument panel, and another set of image generation unit and projection optical system is mounted on the top of the driver's seat. Each set of systems produces virtual images at two different distances. Alternatively, (2), using two image generation units and a set of projection optical systems, for example, as shown in FIG. Equipped with an image generation unit 2 and an image generation unit 3 and a set of projection optical systems 4, respectively, the two image generation units 2, 3 are at different object distances 01, 02 with respect to the projection optical system 4. Generates a virtual image of distance. However, the conventional technology has to use multiple image generation units to generate multiple virtual images at different distances, which not only increases the system cost, but also increases the difficulty of driving, mounting and debugging. .

Therefore, how to improve the above problems is the focus of the technology disclosed by the present invention.

The present invention provides a head-up display system for a motor vehicle, which utilizes a single image generating unit to generate at least two virtual images at different distances to provide sufficient driving information to the driver and An object of the present invention is to simplify the assembly of a head-up display system and reduce the production cost.

An automotive head-up display system according to one embodiment of the present invention includes a windshield and a display device. A windshield is articulated with the body of the vehicle and has a light reflective surface. The display device has an image generation unit and an optical imaging module. The image generating unit is installed in the vehicle body and generates a first image light and a second image light. The optical imaging module is installed at the light exit side of the image generating unit and has at least one plane mirror and at least one first curved mirror to direct the first image light through the first optical path. The second image light is reflected from the surface of the windshield and reflected from the surface of the windshield via the first optical path, thereby generating a first virtual image and a second virtual image, respectively. The distance of the first optical path is shorter than the distance of the second optical path.

A display device according to another embodiment of the invention comprises an image generation unit and an optical imaging module. The image generating unit is installed in the body of the vehicle to generate a first image light and a second image light. The optical imaging module is installed at the light exit side of the image generating unit and has at least one plane mirror and at least one first curved mirror to direct the first image light through the first optical path. The surface of the windshield reflects and the second image light is reflected from the surface of the windshield via the first optical path to generate a first virtual image and a second virtual image, respectively. The distance of the first optical path is shorter than the distance of the second optical path.

The following detailed description of specific embodiments and accompanying drawings will make the objects, technical content, features, and effects achieved of the present invention more comprehensible.

The automotive head-up display system of the present invention utilizes a single image generating unit to generate at least two virtual images at different distances to provide the driver with sufficient driving information and the automotive head-up display system. Simplification of system assembly and reduction of production costs are realized.

1 is a conceptual diagram showing a conventional automobile head-up display system; FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual diagram showing a display device according to an embodiment of the present invention and a vehicle head-up display system using the same. 1 is a conceptual diagram illustrating an image generation unit according to an embodiment of the invention; FIG. FIG. 2 is a conceptual diagram showing a display device according to another embodiment of the present invention and a vehicle head-up display system using the same. FIG. 2 is a conceptual diagram showing a display device according to another embodiment of the present invention and a vehicle head-up display system using the same. FIG. 2 is a conceptual diagram showing a display device according to another embodiment of the present invention and a vehicle head-up display system using the same. 1 is a conceptual diagram illustrating a FOV definition according to one embodiment of the invention; FIG. 1 is a conceptual diagram showing optical paths in a first display area and optical paths in a second display area of a display device according to an embodiment of the present invention and an automotive head-up display system using the same. FIG. 1 is a conceptual diagram showing optical paths in a first display area and optical paths in a second display area of a display device according to an embodiment of the present invention and an automotive head-up display system using the same. FIG. FIG. 4 is a conceptual diagram of a grid image capture simulation of the first display area according to an embodiment of the present invention; FIG. 4 is a conceptual diagram of a grid image capturing simulation of a second display area according to an embodiment of the present invention; FIG. 4 is a conceptual diagram showing the cutoff frequency of each field point of the first display area according to one embodiment of the present invention; FIG. 4 is a conceptual diagram showing cutoff frequencies of each field point of the second display area according to an embodiment of the present invention;

Embodiments of the present invention are described in detail below and illustrated in conjunction with the accompanying drawings. Beyond these detailed descriptions, the invention is also broadly practiced in other embodiments, and simple substitutions, modifications, and equivalent changes of the described embodiments are also included within the scope of the invention. and conclude with the claims. In the written description, numerous specific details are provided in order to provide a thorough understanding of the present invention. However, the invention may be practiced with some or all of the specific details omitted. Additionally, conventional steps and devices have not been shown to avoid unnecessary limitations on the present invention. In the drawings, homologous or similar elements are labeled with homologous or similar symbols. It should be noted that the drawings do not show the actual size or quantity of the elements, and are not drawn in full for the sake of drawing clarity.

FIG. 2 is a conceptual diagram showing a display device according to an embodiment of the present invention and a vehicle head-up display system using the same. As shown in the figure, the automotive head-up display system 10 of the present invention has a windshield 11 and a display device 12 . The windshield 11 is connected to the body 131 of the vehicle 13 and has a surface 111 . The display device 12 has an image generation unit 121 and an optical imaging module 122 . The image generating unit 121 is installed in the vehicle body 131 and generates a first image light (not shown) and a second image light (not shown). The optical imaging module 122 is installed at the light exit side of the image generation unit 121 and has at least one plane mirror 1222 and at least one first curved mirror 1224 to direct the first image light into the first optical path. The second image light is reflected by the surface 111 of the windshield 11 via the second optical path P1 and reflected by the surface 111 of the windshield 11 via the second optical path P2 to form a first virtual image VI1 and a second virtual image VI1 respectively. A virtual image VI2 is generated. The distance of the first optical path P1 is shorter than the distance of the second optical path P2. In one embodiment, the first image light is reflected to the surface 111 of the windshield 11 by at least one first curved mirror 1224, and the second image light is reflected by at least one plane mirror 1222 and at least one The first curved mirror 1224 reflects the light onto the surface 111 of the windshield 11 .

In one embodiment, the image generation unit 121 includes, but is not limited to, a liquid crystal display module, a digital light processing module, a liquid crystal on silicon display module and a laser display module. In one embodiment, referring to FIG. 3, the image generation unit 121 includes an image panel having a first display area 1211 and a second display area 1212, and the first display area 1211 and the second display area 1212 are , to generate a first image light and a second image light, respectively. In another embodiment, image generation unit 121 is a single image panel. In yet another embodiment, to avoid optical path interference, for example, a small portion of the image panel indicated by 1213 is not finally imaged, but for this unused area: Based on different mechanism design, it has different settings. Also, in still other embodiments, the image panel further has a third display area (not shown) to generate a third image, and as above, the image panel has two or two It is possible to have two or more display areas to generate two or more images. As shown in FIG. 3, the present invention utilizes a single image generation unit and divides the display area for image generation so that it can be logically independently operated and physically integrated into multiple units. Form the display area. FIG. 3 illustrates the principle of split utilization with two display areas. A first display area 1211 and a second display area 1212 in FIG. 3 correspond to two virtual images with different final distances. In addition, the division method is not limited to rectangular division, but can be any geometric shape, and in order to adjust the system structure space, the image panel may have a part as an unused area. do not have.

The present invention utilizes optical imaging modules such as plane mirrors, curved mirrors and lenses to align at least one display area with different spatial positions to form different object distances. , to other locations different from the original image source space. Other display areas may be maintained in their original positions or may be converted to other positions in space (where other positions refer to the first The inverted system is imaged at a different location than the imaged location corresponding to the display area. 3 and 4, FIG. 4 is a conceptual diagram showing a display device according to another embodiment of the present invention based on the embodiment of FIG. As shown in the embodiments of FIGS. 3 and 4, the image generation unit 121 is divided into two display areas (a first display area 1211 and a second display area 1212, and one located between the two). ), the light rays emitted by the first display area 1211 are directly irradiated to the first curved mirror 1224 and reflected by the windshield 11 to form the first virtual image (the first virtual image VI1 in FIG. 2 ). The rays emitted by the second display area 1212 are projected onto the plane mirror 1222a to generate the first relay virtual image RVI1 according to the plane mirror imaging principle. The first relay virtual image RVI1 is reflected and formed into a second relay virtual image RVI2 by the plane mirror 1222b. Subsequently, the second relay virtual image RVI2 is reflected and formed into a third relay virtual image RVI3 by the plane mirror 1222c. Thus, the second display area 1212 is transferred to a position different from the original image source position by an optical reversing system composed of plane mirrors 1222a, 1222b, 1222c, ie to a third relay virtual image RVI3. The third relay virtual image RVI3 is further optically projected by curved mirror 1224 and windshield 11 to generate a second virtual image (second virtual image VI2 in FIG. 2). The first display area 1211 unaffected by the reversing system and the third relay virtual image RVI3 (the third relay virtual image RVI3 is the transferred image of the second display area 1212) are at different distances to the curved mirror 1224, and Under reasonable design, both located within the focal point F of the curved mirror, the first virtual image VI1 (as shown in FIG. 2) and the second virtual image VI2 (as shown in FIG. 2) are It has different virtual image distances to the driver 1, and in one embodiment the virtual image distance of the driver 1 from the imaging position of the second virtual image VI2 (as shown in FIG. 2) is greater than 2 meters. The present invention utilizes an optical imaging system to relocate at least one display area to other locations in space to provide multiple display areas with the main projection optical system (i.e., the first curved surface in this embodiment). 1224) have different object distances.

The embodiment of FIG. 4 will be described by taking an optical imaging module composed of three plane mirrors as an example. In yet another embodiment, please refer to FIG. 5, which is a conceptual diagram showing a display device according to another embodiment of the present invention based on the embodiment of FIG. The only difference from FIG. 4 is that the optical imaging module 122 further has a second curved mirror 1225 installed on the second optical path P2 between the imaging unit 121 and at least one first curved mirror 1224. 4, instead of the plane mirror 1222c of the optical imaging module 122, a curved mirror 1225 is installed, and a non-zero degree of refraction is introduced by the curved mirror 1225, as shown in FIG. Therefore, the size of the third relay virtual image RVI3′ is larger than the corresponding second display area 1212 (in FIG. 4, the size of the third relay virtual image RVI3 is equal to the second display area 1212). Alternatively, in one embodiment, as shown in FIG. 6, optical imaging module 122 is composed of plane mirrors 1222a, 1222b, curved mirror 1225, and lens 1226, that is, on the base of the embodiment of FIG. , adding a lens 1226 to correct the optical aberration of the magnifying imaging of the curved mirror 1225, the lens 1226 is installed on the second optical path P2 between the imaging unit and the curved mirror 1225; This is general knowledge in the field of optical design and will not be described in detail. Thus, it can be appreciated that the design of the optical imaging system can be adjusted as needed by those skilled in the art.

According to the above description of the invention, through the action of the optical reversal system, a single image source is transformed into multiple objects having different object distances with respect to the main projection optical system, and according to the Gaussian optical principle, the different distances is generated. In addition, to ensure that the generated virtual image has a practicable image quality, the main projection system must ensure that each standard meets the HUD imaging requirements through optimized optical design. In general, imaging quality standards specify a modulation transfer function ( modulation transfer function (MTF) value, distortion, astigmatism, binocular parallax, and the like. The optimized optical design and evaluation described here are common knowledge to those skilled in the art and will not be described in detail.

Specific embodiments are now provided to describe a vehicle head-up display utilizing a single image generation unit and having multiple virtual image planes according to the present invention. The image generation unit 121 is a single liquid-crystal display (LCD) with a size of 57 mm x 34 mm (diagonal 2.6 inches), which is divided into two parts, 3, the size of the first display area 1211 is 57 mm×14 mm, and the size of the second display area 1212 is 57 mm×16 mm. There is an unused area 1213 that is 57mm x 4mm. The conceptual diagram showing the display device 12 is the same as FIG. 4, the first display area 1211 does not correspond to the reversing system, and the reversing system of the second display area 1212 consists of three plane mirrors (plane mirrors 1222a, 1222b, 1222c). have

The windshield 11 used in this embodiment has a curvature of 7500 mm in the direction perpendicular to the ground and a curvature of 3000 mm in the direction parallel to the ground. When creating a coordinate system in the line of sight of the driver 1 (5° downward viewing angle with respect to the ground), the FOV of the first virtual image VI1 generated by the first display area 1211 is −2.5°, as shown in FIG. ~2.5° (x direction) and -3.5° to -1.5° (y direction), the virtual image distance relative to the driver 1 is 2.5 m. The FOV of the second virtual image VI2 generated by the second display area 1212 is -5° to 5° (x direction) and -0.5° to 2.5° (y direction), and the virtual image distance relative to the driver 1 is 9m. The range in which both eyes can simultaneously appreciate the first virtual image VI1 and the second virtual image VI2 is 120 mm (x direction) and 60 mm (y direction), ie, the eyebox range. The surface type parameters of the curved mirror 1224 of the optical imaging module 122 are described by Equation (1), which is a double curvature equation including a sixth-order aspheric coefficient, specifically as shown in Table 1: Described by the surface parameters of the curved mirror of the optical imaging module 122 . The optical path diagrams of the central field points of each of the two display areas that the driver's eyes are included in are shown in FIGS. 8a and 8b, respectively. , the virtual images are formed at different distances. Equation (1) defining the curved shape of curved mirror 1224 of optical imaging module 122 is as follows:

In terms of imaging quality, this embodiment adds explanations to two important specifications, grid image imaging simulation of two display areas and MTF within the cutoff frequency, as shown in FIGS. 9a and 9b. As shown, the distortion of the virtual images corresponding to the first display area 1211 and the second display area 1212 is very slight, less than 5%. As shown in FIGS. 10a and 10b, any MTF value within the cutoff frequency (8 cycles/mm) that determines the LCD pixel size of the first display area 1211 and the second display area 1212 is , is greater than 0.5, it is a diffraction-limited system, and according to common knowledge in imaging optics, this system provides clear imaging.

As described above, the display device of the present invention and an automobile head-up display system using the same are provided with at least two image generation units by the image generation unit of the display device, and are logically independently It forms a display area that is operational and physically unitary. The optical imaging module of the display device has at least one flat mirror and at least one curved mirror, and elastically performs different reversal arrangements according to different image generation units to at least two distinct Individual virtual images are formed.

Taken together, the display device of the present invention, and the automotive head-up display system using it, utilizes a single image generation unit to generate at least two virtual images at different distances, providing a sufficient distance for the driver. It provides driving information, simplifies the assembly of the automotive head-up display system, and reduces production costs.

1 drivers 2, 3 image generation unit 4 projection optical system VI_1, VI_2 virtual images VI_P1, VI_P2 virtual image distances O1, O2 object distance 10 automobile head-up display system 11 windshield 111 surface 12 display device 121 image generation unit 1211 first display area 1212 second display area 1213 unused area 122 optical imaging module 1222, 1222a, 1222b, 1222c plane mirror 1224, 1225 curved mirror 1226 lens 13 vehicle 131 vehicle body F focus P1 first optical path P2 second optical path RVI1 first relay virtual image RVI2 Second relay virtual image RVI3, RVI3' Third relay virtual image VI1 First virtual image VI2 Second virtual image

Claims (6)

An automotive head-up display system comprising:
a windshield articulated with the body of the vehicle and having a surface reflecting light rays;
an image generation unit installed in the vehicle body for generating a first image light and a second image light;
at least two plane mirrors;
a first curved mirror;
a second curved mirror;
one lens and
an optical imaging module, wherein the distance of the first optical path is less than the distance of the second optical path;
The plane mirror and the first curved mirror are installed on the light exit side of the image generation unit,
The first image light passes through the first optical path in which the light emitted from the image generation unit is reflected by the first curved mirror and reaches the surface of the windshield to generate a first virtual image,
The second image light passes through a second optical path in which the light emitted from the image generation unit is reflected by the plane mirror, then reflected by the first curved mirror, and reaches the surface of the windshield. generate a virtual image,
By placing the plane mirror on the second optical path, the first virtual image and the second virtual image form different virtual image distances to the driver, and are placed in front of the first curved mirror on the second optical path. the second curved mirror is configured to produce a magnified image;
The lens is arranged on the second optical path between the second curved mirror and the first curved mirror, and the lens corrects optical aberration of the magnified image.
A head-up display system characterized by: 2. The head-up display system as claimed in claim 1, wherein said image generating unit comprises a liquid crystal display module, a digital light processing module, a liquid crystal on silicon display module and a laser display module. The image generation unit includes an image panel having a first display area and a second display area, and the first display area and the second display area respectively correspond to the first image light and the 2. The head-up display system of claim 1, wherein the second image light is generated. A display device for an automotive head-up display system according to claim 1,
the image generation unit installed in the body of the vehicle for generating the first image light and the second image light;
at least two of the plane mirrors;
one said first curved mirror;
one of the second curved mirrors;
one said lens;
an optical imaging module in which the distance of the first optical path is less than the distance of the second optical path;
The plane mirror and the first curved mirror are installed on the light exit side of the image generation unit,
The first image light passes through the first optical path in which the light emitted from the image generation unit is reflected by the first curved mirror and reaches the surface of the windshield to generate the first virtual image,
The second image light passes through the second optical path in which the light emitted from the image generation unit is reflected by the plane mirror, then reflected by the first curved mirror, and reaches the surface of the windshield. generate a second virtual image,
By placing the plane mirror on the second optical path, the first virtual image and the second virtual image form different virtual image distances to the driver, and are placed in front of the first curved mirror on the second optical path. said second curved mirror that produces a magnified image,
The lens is arranged on the second optical path between the second curved mirror and the first curved mirror, and the lens corrects optical aberration of the magnified image.
A display device characterized by: 5. The display device of claim 4, wherein the image generation unit comprises a liquid crystal display module, a digital light processing module, a liquid crystal on silicon display module and a laser display module. The image generation unit includes an image panel having a first display area and a second display area, and wherein the first display area and the second display area respectively correspond to the first image light and , to generate the second image light.

Images