CN213715609U

CN213715609U - AR-HUD of big eyebox

Info

Publication number: CN213715609U
Application number: CN202022479239.5U
Authority: CN
Inventors: 蒋厚强; 朱以胜
Original assignee: Shenzhen Qize Technology Partnership LP
Current assignee: Shenzhen Qize Technology Partnership LP
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2021-07-16
Anticipated expiration: 2030-10-30

Abstract

The utility model provides a big eyebox's AR-HUD, include: a light engine part which generates image information and outputs it; an optical waveguide sheet fixedly connected to the light engine part for coupling into the image information outputted from the light engine part and transmitting the image information to the eyebox area; the angle selection film is fixedly arranged on the optical waveguide sheet and reflects the solar rays irradiating the optical waveguide sheet; the membrane is selected to the angle and the light engine part sets up in same one side of optical waveguide piece, the membrane is selected to the angle is located optical waveguide piece and windshield one side relative, borrows this, the utility model has the advantages of the life that has promoted the system, effectual protection system do not receive the influence of sunlight, the virtual image distance of formation of image is far away to can be littleer with horizontal contained angle, the driver watches information eyes no longer need constantly zoom, reduce and drive fatigue.

Description

AR-HUD of big eyebox

Technical Field

The utility model belongs to the technical field of on-vehicle new line shows, in particular to AR-HUD of big eyebox.

Background

At present, in the driving process of a driver, important information such as vehicle speed and navigation needs to be regularly observed to assist in driving, and the driver generally needs to hold down to check the instrument panel of the automobile to acquire the information. And if the virtual image formed by the Head-Up Display falls in front of the sight line of the driver, the driver can conveniently view the vehicle information, and the driving safety is greatly improved.

The existing HUD based on the optical waveguide technology is imaged through a semi-transparent semi-reflecting mirror, on one hand, the road surface condition is watched through the reflecting mirror, on the other hand, a projection image source is reflected by the reflecting mirror and enters a human eye area, and the image source reflected by the reflecting mirror is generally a display screen such as LCOS (liquid Crystal on silicon), Micro-LED (Micro-light emitting diode) and the like or a primary image surface projected by DLP (digital light processing).

Traditional windscreen formula HUD sunlight irradiation HUD under certain angle to form through the internal reflection mirror reflection and assemble the facula. Because the facula that assembles can carry the energy, can heat display screen and peripheral part damage even to influence the life-span that the HUD used.

The utility model provides a new line display system based on optical waveguide has been proposed in chinese utility model patent CN207216154U, and the shortcoming of its existence is that the system optical efficiency of optical waveguide is low, and luminance homogeneity is poor, and the framework receives the restriction of grating design, and waveguide imaging definition is not high, and the light engine part receives shining of sunlight and leads to the life-span short.

The utility model provides a windscreen formula HUD has been proposed in the Chinese utility model patent CN207374131U, and the shortcoming of its existence is that the optical waveguide system optical efficiency of reflective is low, and luminance homogeneity is poor, and eyebox scope ratio is more limited, and the optical waveguide part can not rotation angle at will, and inconvenient regulation and control position occupies space.

The utility model discloses an on-vehicle AR-HUD based on DLP is disclosed in chinese utility model patent application CN109491089A, and the problem that its exists is that system efficiency is not high, and eyebox scope is more limited, and the sunlight can produce harm reduction life to the light engine part, and the optical waveguide part can not rotate angle at will, and inconvenient regulation and control position occupies space.

In summary, the conventional vehicle-mounted HUD has the following problems:

1. the image source (display screen) is easily damaged due to the irradiation of sunlight for a long time;

2. the traditional HUD has a short imaging distance, and when a driver watches display pictures such as navigation and the like, the glasses zoom continuously, so that visual fatigue is easy to generate while the interactivity is poor;

3. the eyebox of the traditional HUD is small, the field of view is small, and the display content is limited.

SUMMERY OF THE UTILITY MODEL

The utility model provides a big eyebox's AR-HUD can solve among the prior art image source (display screen) and receive the shining of sunlight for a long time, damages easily, and the driver produces visual fatigue easily, and eyebox is little, and the visual field is little, shows the limited problem of content.

The technical scheme of the utility model is realized like this: an AR-HUD of a large eyebox comprising:

a light engine part which generates image information and outputs it;

an optical waveguide sheet fixedly connected to the light engine part for coupling into the image information outputted from the light engine part and transmitting the image information to the eyebox area;

the angle selection film is fixedly arranged on the optical waveguide sheet and reflects the solar rays irradiating the optical waveguide sheet;

the angle selection film and the light engine portion are disposed on the same side of the optical waveguide sheet, and the angle selection film is located on the opposite side of the optical waveguide sheet from the windshield.

The utility model comprises a diffraction light wave guide sheet, an angle reflection film and the like. The optical engine part couples the image source into the optical waveguide sheet through an optical waveguide input coupling end, and the image source enters an eyebox area near the driver glasses after being transmitted through the optical waveguide sheet. In the eyebox area, the driver views the projected head-up display through the optical waveguide screen. Compare AR-HUD design in the past, the utility model provides an what HUD utilized is the form of diffraction optical waveguide, and the rotation of angle can be realized to collocation angle selection membrane, and sunlight, the part among the effectual protection HUD are fallen in reflection that the angle selection membrane can be fine. The optical waveguide screen has no focal power, and a driver can watch a road scene without deformation and scaling through the optical waveguide screen.

As a preferable technical solution, the optical waveguide sheet includes an entrance pupil region, an exit pupil region, and an expanded pupil region, and image information generated by the light engine part is coupled into the diffractive optical waveguide sheet (WG), and light is bound to the glass to propagate due to total reflection of the glass in the optical waveguide sheet, and when the light reaches the expanded pupil and the exit pupil region, the expanded pupil and the exit pupil are performed. The light passing through the extended pupil region and the exit pupil is imaged after passing through an angle reflecting film (ANGF).

As a preferable technical solution, the entrance pupil region is either a surface grating or a prism coupling grating, the pupil expanding region is either a gradient surface grating or a gradient volume grating, and the exit pupil region is a gradient volume grating.

As a preferred technical scheme, it is regional for surface relief (sculpture) grating to go into pupil and expand the pupil, and the exit pupil is regional for the holographic grating of body, more than, the utility model discloses just the most effective slited grating or directly adopt the prism coupling in the area of the entrance pupil, improve incident regional efficiency to the highest. The pupil expanding area adopts a gradually changed surface grating or a body grating to control the uniformity of the pupil expanding. The exit pupil area adopts a gradual-change volume grating, and the characteristic of narrow response wavelength of the volume grating is utilized, so that the color brightness uniformity of the image is ensured, and the influence of color stripes of ambient light is eliminated.

As a preferred technical scheme, the light engine part comprises a Micro display screen and a projection lens module, the Micro display screen is any one of a DLP screen, an Lcos screen, a Micro-LED screen or a Micro-OLED screen, the size of the Micro display screen is 0.2-0.4 inch, and the resolution of the Micro display screen is 1080 p.

As a preferable technical solution, the thickness of the angle selection film is 2mm, the angle selection film can reflect light rays at a specific angle, generally, light rays smaller than about 75 degrees (included angle between the light rays and the film) are all reflected back and do not enter the optical waveguide sheet, light rays larger than 75 degrees will transmit through the waveguide sheet and also do not enter the waveguide sheet, and damage of sunlight to the system is reduced. The waveguide plate has the characteristic that light rays with small angle incidence enter the waveguide plate, and light rays with large angle pass through the waveguide plate. The whole framework of the diffraction optical waveguide is redesigned, the maximum entrance pupil coupling efficiency, the optimal pupil expanding mode and the reasonable emergent area are realized through the implementation modes and the process differences of different functional areas, the problem of the efficiency of the common light waveguide is solved, meanwhile, the influence of color diffraction stripes of the exit pupil area of the waveguide under the irradiation of ambient light is improved, and therefore the user experience brought by the diffraction optical waveguide in AR display is integrally improved.

After the technical scheme is adopted, the beneficial effects of the utility model are that:

under the prerequisite that does not influence on-vehicle demonstration, very big promotion the life of system, effectual protection system does not receive the influence of sunlight. The eyebox area is greatly enlarged through the form of the diffraction optical waveguide, and more information is displayed. Due to the whole rotatability, the space of the vehicle is more effectively utilized, the angle selection film is utilized to be matched with the waveguide, the system is not affected by the irradiation of sunlight, and the service life of the whole system is prolonged. The virtual image distance of formation of image is far away to can be littleer with horizontal contained angle, the driver watches the information eyes and no longer need constantly zoom, reduces and drives fatigue.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

FIG. 1 is a schematic diagram of the system of the present invention;

fig. 2 is a schematic view of a system according to another embodiment of the present invention;

FIG. 3 is a schematic view of the structure of the diffractive optical waveguide sheet in cooperation with an angle selection film;

FIG. 4 is a top view of a waveguide sheet;

FIG. 5 is a schematic diagram of a diffractive light waveguide system;

figure 6 is a schematic view of the working process of the entrance pupil area and the expansion pupil area;

FIG. 7 is a diagram illustrating a specific grating topography in the entrance pupil region;

figure 8 is a schematic view of the grating topography in the exit pupil region;

FIG. 9 is a schematic structural diagram of a volume holographic grating in an exit pupil region;

FIG. 10 is a directional schematic of the period of the overlapping gratings.

In the figure, 1 — the light engine part; 2-an optical waveguide sheet; 3-angle selective membrane; 4-a windshield; 21-entrance pupil region; 22-exit pupil region; 23-pupil expansion zone.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Referring to fig. 1 to 10, in a first embodiment: an AR-HUD of a large eyebox comprising:

a light engine section 1 which generates image information and outputs it;

an optical waveguide sheet 2 fixedly connected to the light engine part 1 for coupling in image information outputted from the light engine part 1 and transmitting the image information to the eyebox area;

an angle selection film 3 fixedly provided on the optical waveguide sheet 2 to reflect solar rays irradiating the optical waveguide sheet 2;

the angle selection film 3 and the light engine section 1 are disposed on the same side of the optical waveguide sheet 2, and the angle selection film 3 is located on the side of the optical waveguide sheet 2 opposite to the windshield 4.

The utility model comprises a diffraction light wave guide sheet, an angle reflection film and the like. The optical engine part 1 couples the image source into the optical waveguide sheet 2 through an optical waveguide input coupling end, and after passing through the inside of the optical waveguide sheet 2, enters the eyebox area near the driver's glasses. In the eyebox area, the driver views the projected head-up display through the optical waveguide screen. Compare AR-HUD design in the past, the utility model provides an what HUD utilized is the form of diffraction optical waveguide, and collocation angle selection membrane 3 can realize the rotation of angle, and sunlight, the part among the effectual protection HUD are fallen in reflection that angle selection membrane 3 can be fine. The optical waveguide screen has no focal power, and a driver can watch a road scene without deformation and scaling through the optical waveguide screen.

The optical waveguide sheet 2 includes an entrance pupil region, an exit pupil region, and an expanded pupil region, and image information generated by the light engine part 1 is coupled into the diffractive optical waveguide sheet 2 (WG), and light is bound to the glass to propagate due to total reflection of the glass in the optical waveguide sheet 2, and then expanded and exit pupils are performed after the light reaches the expanded and exit pupil regions. The light passing through the extended pupil region and the exit pupil is imaged after passing through an angle reflecting film (ANGF).

The entrance pupil area is the heavy arbitrary one of surface grating or prism coupling, the pupil area is in the surface grating or the any one of body grating of gradual change, the exit pupil area is the body grating of gradual change, entrance pupil and pupil area are surface relief grating, the exit pupil area is the holographic grating of body, light engine part 1 is including little display screen and projection lens module, little display screen is any one of DLP screen, Lcos screen, Micro-LED screen or Micro-OLED screen, the size of little display screen is between 0.2 ~ 0.4 inch, the resolution ratio of little display screen is more than 1080p, the utility model discloses just the highest contained grating of high efficiency is directly adopted the prism coupling in the entrance pupil area, improves the efficiency in incident area to the highest. The pupil expanding area adopts a gradually changed surface grating or a body grating to control the uniformity of the pupil expanding. The exit pupil area adopts a gradual-change volume grating, and the characteristic of narrow response wavelength of the volume grating is utilized, so that the color brightness uniformity of the image is ensured, and the influence of color stripes of ambient light is eliminated.

The thickness of the angle selection film 3 is 2mm, the angle selection film 3 can reflect light rays at a specific angle, generally, light rays smaller than about 75 degrees (included angle between the light rays and the film) are totally reflected and do not enter the optical waveguide sheet 2, the light rays larger than 75 degrees will transmit through the optical waveguide sheet and do not enter the optical waveguide sheet, and damage of sunlight to a system is reduced. The waveguide plate has the characteristic that light rays with small angle incidence enter the waveguide plate, and light rays with large angle pass through the waveguide plate. The whole framework of the diffraction optical waveguide is redesigned, the maximum entrance pupil coupling efficiency, the optimal pupil expanding mode and the reasonable emergent area are realized through the implementation modes and the process differences of different functional areas, the problem of the efficiency of the common light waveguide is solved, meanwhile, the influence of color diffraction stripes of the exit pupil area of the waveguide under the irradiation of ambient light is improved, and therefore the user experience brought by the diffraction optical waveguide in AR display is integrally improved.

The utility model provides a big eyebox's AR-HUD based on diffraction light waveguide not only has traditional HUD and will navigate, information display such as vehicle conditions in driver's the place ahead function of looking up the within range, but also can realize big eyebox. HUD can realize the angular rotation, and the angle is selected the membrane 3 layers on the cooperation, and the sunlight that has certain reflection small angle to the sunlight of wide angle has the transmission effect to can effectively reduce the sunlight and get into the system, reduce the harm to the light engine. And the advantages of long virtual image distance, small included angle with the horizontal direction and the like can be realized.

The utility model belongs to the AR-HUD's of utilizing the diffraction optical waveguide mode among the on-vehicle demonstration HUD, this system main utility model is including diffraction optical waveguide guide piece, angle reflectance coating etc.. The optical engine part 1 couples the image source into the optical waveguide through an optical waveguide input coupling end, and after the image source is transmitted through the optical waveguide, the image source enters an eyebox area near the glasses of the driver. In the eyebox area, the driver views the projected head-up display through the optical waveguide screen. Compare AR-HUD design in the past, what HUD in this example used is the form of diffraction optical waveguide, and collocation angle selection membrane 3 can realize the rotation of angle, and sunlight, the part among the effectual protection HUD are fallen in reflection that angle selection membrane 3 can be fine. The optical waveguide screen has no focal power, and a driver can watch a road scene without deformation and scaling through the optical waveguide screen.

The HUD working diagram using the diffractive optical waveguide of the present invention is shown in fig. 1. LT is an element that senses ambient light, typically as a reference for display brightness adjustment. The light engine LE part consists of Panel + lens. Panel refers to a Micro display screen, generally using DLP, Lcos, Micro-LED, Micro-OLED and other screens, with the size controlled around 0.3 inch and resolution generally 1080p or higher. Lens is a projection Lens module with + fingers, the diameter of the entrance pupil is controlled to be about several millimeters, and the number of lenses is generally 5-8. The image information generated by the light engine part 1 is coupled into the diffractive optical waveguide sheet 2 (WG), and light is confined in the glass and propagates due to total reflection by the glass in the optical waveguide sheet 2, and after reaching the pupil expanding region, the light undergoes pupil expansion, and a part of the light continues to propagate rightward, and another part of the light propagates toward the exit pupil. The light rays are coupled out through an exit pupil area after expanding the pupil, and the exit pupil area has the function of expanding the pupil while coupling the light rays into human eyes. The angle selection film 3(ANGF) is a film that reflects light rays of a specific incident angle, the thickness of the film layer is generally 2mm, and the angle selection film 3 is attached to the waveguide plate. The light passing through the expanding pupil and the exit pupil enters human eyes after being reflected and imaged by an angle reflecting film (ANGF) and a windshield 4 (WIN). The human eye perceives the virtual image as falling at a location which is not at a substantial angle (theta) to the normal line of sight of the human eye, where theta is typically within 5 degrees.

The human eye can also directly observe the image of the vehicle information right in front of the visual field through the waveguide sheet without entering the human eye through reflection of the vehicle windshield 4, so that the efficiency of the system is further improved, as shown in fig. 2. The image information generated by the light engine part 1 is coupled into a Waveguide (WG), the light is bound in the glass to propagate due to the total reflection of the glass, when the light reaches the pupil expanding and exit pupil areas, the light is expanded and exited, and the light passing through the pupil expanding and exit pupil directly enters human eyes.

The utility model discloses utilize the diffraction optical waveguide piece 2 of special grating to come incident region's efficiency to improve to the highest, promoted luminance homogeneity when promoting overall efficiency, increased eyebox, eyebox indicates the region that human eye can watch. The angle reflective film is capable of preventing solar rays from irradiating the waveguide sheet and entering the light engine part 1. And the light guide part and the angle selection film 3 can realize the rotation of the angle, the adjustment of the eye box of the human eye can be further realized by the adjustable structure, and the space of the vehicle can be effectively utilized by the whole angle rotatability.

The utility model relates to a structure of a diffraction optical waveguide piece 2 matched with an angle selection film 3, as shown in figure 3. The image information generated by the light engine part 1 is coupled into the diffractive optical waveguide sheet 2 (WG), and light is confined in the glass to propagate due to total reflection of the glass in the optical waveguide sheet 2, and when the light reaches the pupil expanding and exit pupil regions, the pupil expanding and exit pupils are performed. The light passing through the extended pupil and the exit pupil is imaged after passing through an angle reflecting film (ANGF). The angle selection film 3 can reflect light rays at a specific angle, generally, light rays smaller than about 75 degrees (included angle between the light rays and the film) are totally reflected and do not enter the optical waveguide sheet 2, the light rays larger than 75 degrees will transmit through the optical waveguide sheet and do not enter the optical waveguide sheet, and damage of sunlight to a system is reduced. The waveguide plate has the characteristic that light rays with small angle incidence enter the waveguide plate, and light rays with large angle pass through the waveguide plate. The whole framework of the diffraction optical waveguide is redesigned, the maximum entrance pupil coupling efficiency, the optimal pupil expanding mode and the reasonable emergent area are realized through the implementation modes and the process differences of different functional areas, the problem of the efficiency of the common light waveguide is solved, meanwhile, the influence of color diffraction stripes of the exit pupil area of the waveguide under the irradiation of ambient light is improved, and therefore the user experience brought by the diffraction optical waveguide in AR display is integrally improved.

The top view structure of the waveguide sheet is schematically shown in fig. 4, and the waveguide sheet has three regions, i.e., an entrance pupil region, an exit pupil region, and an expanded pupil region. The three areas utilize special design and change the processing mode thereof, thereby improving the overall efficiency of the optical waveguide and eliminating the color diffraction fringes of the exit pupil area under the ambient light.

The diffraction light waveguide system structure of the utility model is as shown in fig. 5, with the transmission main part of plate glass as the waveguide, the optical engine part comprises panel and lens, inside the image information that optical engine part 1 produced led into the waveguide from the entrance pupil region, because the total reflection of glass, light was tied and is propagated in glass (as in fig. 5), after light reachd the pupil expanding region, expand the pupil, partly continue to propagate to the right, another part propagates towards the exit pupil direction. The light rays are coupled out through an exit pupil area after expanding the pupil, and the exit pupil area has the function of expanding the pupil while coupling the light rays into human eyes. The pupil area adopts a specially designed surface grating or prism coupling, the pupil expanding area adopts a specially designed surface grating or volume grating, and the exit pupil area adopts a specially designed volume grating.

Because diffraction light waveguide efficiency that conventional AR shows is very low, the utility model discloses only the highest slaged grating of efficient or directly adopt the prism coupling in the entrance pupil region, improve incident regional efficiency to the highest. The pupil expanding area adopts a gradually changed surface grating or a body grating to control the uniformity of the pupil expanding. The exit pupil area adopts a gradual-change volume grating, and the characteristic of narrow response wavelength of the volume grating is utilized, so that the color brightness uniformity of the image is ensured, and the influence of color stripes of ambient light is eliminated.

The present embodiment is an optical waveguide of relief body compound hologram, different functional regions of the grating are shown in fig. 4, wherein the entrance pupil region and the extended pupil region are surface relief gratings, and the exit pupil region is a body hologram grating. The grating is designed in a partition mode, and the function of an AR diffraction optical waveguide can be achieved. For the grating incident light in the left of fig. 4 to enter the entrance pupil region, the specific grating profile of the entrance pupil region is as follows, a tilted grating with fixed period. The exit pupil area is a tilted grating or a binary grating with fixed period, but the parameters such as duty ratio and height are modulated along with the position.

The exit pupil area is a volume holographic grating, the period of the grating is fixed, the modulation depth of the grating gradually changes along with the position, and the influence of ambient stray light is eliminated due to the wavelength selectivity of the volume holographic grating. The volume holographic grating is schematically shown as follows, the grating is written into a recording material through an exposure process, and refractive index fluctuation with fixed period is formed inside the material.

The pupil expanding area and the exit pupil area are volume grating waveguides with two-dimensional structures, and overlapped 2D gratings of the two gratings are formed through multiple exposure on the basis of the volume gratings, wherein the directions of the periods of the overlapped gratings are shown in the figure.

Under the prerequisite that does not influence on-vehicle demonstration, very big promotion the life of system, effectual protection system does not receive the influence of sunlight. The eyebox area is greatly enlarged through the form of the diffraction optical waveguide, and more information is displayed. Due to the whole rotatability, the space of the vehicle is more effectively utilized, the angle selection film 3 is utilized to be matched with the waveguide, the system is not affected by the irradiation of sunlight, and the service life of the whole system is prolonged. The virtual image distance of formation of image is far away to can be littleer with horizontal contained angle, the driver watches the information eyes and no longer need constantly zoom, reduces and drives fatigue.

The embodiment is a scheme that an AR-HUD using a diffraction light waveguide technique in combination with an angle selection film 3 can realize a large eyebox, a long system life, and a better virtual image position.

Example two: an AR-HUD of a large eyebox comprising:

a light engine section 1 which generates image information and outputs it;

Another AR-HUD system derived for this configuration is shown in fig. 7, with LT being the element that senses ambient light, typically as a reference for display brightness adjustment. The light engine part 1LE is composed of Panel + lens. Panel refers to a Micro display screen, generally using DLP, Lcos, Micro-LED, Micro-OLED and other screens, with the size controlled around 0.3 inch and resolution generally 1080p or higher. Lens is the projection Lens module, the diameter of the entrance pupil is controlled to be about several millimeters, and the number of lenses is generally 5-8. The image information generated by the light engine part 1 is coupled into the diffractive optical waveguide sheet 2 (WG), and light is confined in the glass and propagates due to total reflection by the glass in the optical waveguide sheet 2, and after reaching the pupil expanding region, the light undergoes pupil expansion, and a part of the light continues to propagate rightward, and another part of the light propagates toward the exit pupil. The light rays are coupled out through an exit pupil area after expanding the pupil, and the exit pupil area has the function of expanding the pupil while coupling the light rays into human eyes. The angle selection film 3(ANGF) is a film that reflects light of a specific incident angle well, and the thickness of the film layer is generally 2mm, and the angle selection film 3 is attached to the waveguide sheet. The waveguide sheet directly couples image information into human eyes, reflection of the windshield 4 of the automobile is avoided, the human eyes can view virtual images directly through the waveguide sheet, angular deviation is avoided, the driver's light feeling is improved, and the efficiency of the whole system is further improved without reflection and re-imaging of the windshield 4.

Overall technical solution of optical waveguide sheet 2 referring to example 1

The image information of the embodiment is directly imaged on human eyes through the optical waveguide sheet 2, the efficiency of the system is further improved, the eyebox is enlarged, and the visible area is enlarged. Human eyes directly watch virtual images through the waveguide sheet without angular deviation, and the ease of a driver is improved.

The embodiment two of the utility model is different from the improvement of the embodiment one

The uniformity of the image color brightness is better, the system efficiency is further enhanced, and the influence of color stripes of ambient light is eliminated while the uniformity of the image color brightness is ensured.

The diffractive optical waveguide sheet 2 is matched with the angle selection film 3 to increase the system efficiency and increase the eyebox, and simultaneously, the diffractive optical waveguide sheet 2 of the optical engine is protected to improve the system efficiency and increase the eyebox.

The utility model discloses in, utilize diffraction optical waveguide's form to increase entire system's efficiency, redesigned the entrance pupil in the optical waveguide piece 2, expand pupil, exit pupil region, the surface grating or the prism coupling that the entrance pupil region adopted special design, expand pupil region and adopt special design's surface grating or body grating, exit pupil region adopts special design's body grating. The specific grating of the entrance pupil region is a tilted grating with a fixed period. The exit pupil area is an inclined grating or a binary grating with a fixed period, but parameters such as duty ratio, height and the like are modulated along with the position, the exit pupil area is a volume holographic grating, the period of the grating is fixed, the modulation depth of the grating is gradually changed along with the position, and the influence of ambient stray light is eliminated due to the wavelength selectivity of the volume holographic grating. The volume holographic grating is schematically shown as follows, the grating is written into a recording material through an exposure process, and refractive index fluctuation with fixed period is formed inside the material. See the first embodiment for a detailed description.

The angle selection film 3(ANGF) is a film that reflects light rays of a specific incident angle, the thickness of the film layer is generally 2mm, and the angle selection film 3 is attached to the waveguide plate. The angle selection film 3 can reflect light rays at a specific angle, generally, light rays smaller than about 75 degrees (included angle between the light rays and the film) are totally reflected, and light rays larger than 75 degrees are transmitted through the film layer. Thus, incident light rays are selectively screened out, and the influence of sunlight on the system is reduced or even eliminated.

The angle selection film 3 is attached to the optical waveguide sheet 2 and can be rotated as a whole. The optical waveguide part and the angle selection film 3 can realize the rotation of the angle, the adjustment of the eye box of a human eye is further realized by the adjustable structure, and the space of a vehicle can be effectively utilized by the integral angle rotatability.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, mechanically or electrically connected, or may be connected between two elements through an intermediate medium, or may be directly connected or indirectly connected, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An AR-HUD of a large eyebox, comprising:

a light engine part which generates image information and outputs it;

2. The large eyebox AR-HUD according to claim 1, wherein said optical waveguide sheet includes an entrance pupil region, a pupil expanding region and an exit pupil region.

3. A large eyebox AR-HUD according to claim 2, wherein said entrance pupil region is either a surface grating or a prism coupling, said pupil expanding region is either a graded surface grating or a volume grating, and said exit pupil region is a graded volume grating.

4. A large eyebox AR-HUD as claimed in claim 3, wherein said entrance and exit pupil regions are surface relief gratings and exit pupil regions are volume holographic gratings.

5. The large eyebox AR-HUD as recited in claim 1, wherein said light engine section includes a microdisplay screen and a projection lens module.

6. The AR-HUD of the large eyebox according to claim 5, characterized in that said Micro display screen is any one of DLP screen, Lcos screen, Micro-LED screen or Micro-OLED screen, the size of said Micro display screen is 0.2-0.4 inches, the resolution of said Micro display screen is 1080p or more.

7. A large eyebox AR-HUD as claimed in claim 1, wherein said angle selective membrane has a thickness of 2 mm.