CN113238379A

CN113238379A - Head-up display system, driving method of head-up display system and vehicle

Info

Publication number: CN113238379A
Application number: CN202110548268.9A
Authority: CN
Inventors: 顾跃凤; 王建栋
Original assignee: Shanghai Tianma Microelectronics Co Ltd
Current assignee: Shanghai Tianma Microelectronics Co Ltd
Priority date: 2021-05-19
Filing date: 2021-05-19
Publication date: 2021-08-10
Anticipated expiration: 2041-05-19
Also published as: CN113238379B

Abstract

The invention discloses a head-up display system, a driving method of the head-up display system and a vehicle. The head-up display system comprises a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least one polarization state adjusting unit and at least two metal wire grids, and the reflection module comprises at least two reflectors; the image source module is electrically connected with the control module and is used for emitting imaging light under the control of the control module; the polarization state adjusting unit is electrically connected with the control module and is used for modulating the polarization state of the imaging light rays so as to enable the imaging light rays to be transmitted to the imaging module through the metal wire grating or enable the imaging light rays to be incident to the imaging module after being reflected by the metal wire grating and the reflector; the imaging module is used for transmitting imaging light to the windshield, and the windshield reflects the imaging light into human eyes for imaging. The invention realizes the AR-HUD of the single display screen through the image source and the dimming module, and has the advantages of small volume and low cost.

Description

Head-up display system, driving method of head-up display system and vehicle

Technical Field

The embodiment of the invention relates to a head-up display technology, in particular to a head-up display system, a driving method of the head-up display system and a vehicle.

Background

Head Up Display (HUD) is gradually finding wide application in the automotive field. The head-up display is to project important information (such as vehicle speed, navigation and the like) displayed by an instrument in the driving process of an automobile to a front windshield, so that a driver can see the information in the instrument without lowering the head, a novice inexperienced in speed judgment can be helped to control the vehicle speed of the driver, the condition that the speed is violated due to overspeed in a speed-limiting road section is avoided, and more importantly, the head-up display can enable the driver to read instantly under the condition that the large visual field is not transferred, and the optimal observation state is always kept.

The AR-HUD should have the function of displaying conventional information such as vehicle speed and oil consumption of the existing HUD, and can also realize the function of augmented reality. Therefore, it is necessary to realize projected images at two different distances in front of the vehicle. In the existing AR-HUD optical system, two display screens are generally used, and two paths of reflection are realized through optical design, so that simultaneous imaging of a near view and a far view is realized. Although this solution realizes simultaneous imaging of a near view and a far view, the use of two sets of image Generating units (PGUs) and lighting units results in an oversized product, high heat dissipation requirements and high cost.

Disclosure of Invention

The embodiment of the invention provides a head-up display system, a driving method of the head-up display system and a vehicle.

In a first aspect, an embodiment of the present invention provides a head-up display system, including a control module, an image source module, a dimming module, a reflection module, and an imaging module, where the dimming module includes at least one polarization state adjustment unit and at least two metal wire grids, and the reflection module includes at least two mirrors;

the image source module is electrically connected with the control module and is used for emitting imaging light rays under the control of the control module;

the polarization state adjusting unit is electrically connected with the control module and is used for modulating the polarization state of the imaging light rays so as to enable the imaging light rays to be transmitted to the imaging module through the metal wire grid or enable the imaging light rays to be incident to the imaging module after being reflected by the metal wire grid and the reflector;

the imaging module is used for transmitting the imaging light to a windshield, and the windshield reflects the imaging light into human eyes for imaging.

In a second aspect, an embodiment of the present invention further provides a head-up display system, including a control module, an image source module, a dimming module, a reflection module, and an imaging module, where the dimming module includes at least two metal wire grids, and the reflection module includes at least two reflectors;

the image source module is electrically connected with the control module, the image source module comprises a display unit and a polarization state adjusting unit positioned on the light emitting side of the display unit, the display unit is used for emitting imaging light under the control of the control module, and the polarization state adjusting unit is used for modulating the polarization state of the imaging light so as to enable the imaging light to be transmitted to the imaging module through the metal wire grid or enable the imaging light to be incident to the imaging module after being reflected by the metal wire grid and the reflector;

In a third aspect, an embodiment of the present invention further provides a driving method of a head-up display system, where the head-up display system includes a control module, an image source module, a dimming module, a reflection module, and an imaging module, the dimming module includes at least one polarization state adjustment unit and at least two metal wire grids, the reflection module includes at least two mirrors, or the image source module includes a display unit and a polarization state adjustment unit located on a light exit side of the display unit, the dimming module includes at least two metal wire grids, and the reflection module includes at least two mirrors; the driving method includes:

the control module controls the image source module to emit imaging light;

the polarization state adjusting unit modulates the polarization state of the imaging light so as to enable the imaging light to be in a first display time period t₁Is transmitted to the imaging module through the metal wire grid to enable the imaging light to be in a second display time period t₂Passing through the metal wire grid andthe reflector reflects the light and then enters the imaging module.

In a fourth aspect, an embodiment of the present invention further provides a vehicle, including the above head-up display system.

The head-up display system provided by the embodiment of the invention comprises a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least one polarization state adjusting unit and at least two metal wire grids, and the reflection module comprises at least two reflectors; imaging light rays are emitted under the control of the control module through the image source module; the polarization state of the imaging light is modulated by the polarization state adjusting unit, so that the imaging light is transmitted to the imaging module through the metal wire grid, or the imaging light is reflected by the metal wire grid and the reflector and then is incident to the imaging module, and the light of the two paths forms images with different depths of field; the imaging light is transmitted to the windshield through the imaging module, the windshield is reflected to enter human eyes for imaging, and therefore the head-up display effect of augmented reality is achieved through one imaging source and the dimming module, the volume of the head-up display system is smaller, and the cost is lower.

Drawings

Fig. 1 is a schematic structural diagram of a head-up display system provided in the related art;

FIG. 2 is an enlarged partial schematic view of FIG. 1;

fig. 3 is a schematic structural diagram of another head-up display system provided in the related art;

fig. 4 is a schematic structural diagram of a head-up display system according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of another embodiment of a head-up display system;

fig. 6 and 7 are schematic structural diagrams of another head-up display system according to an embodiment of the invention;

FIG. 8 is a schematic optical path diagram of the heads-up display system shown in FIG. 6 during a second time period;

FIG. 9 is a schematic optical path diagram of the heads-up display system shown in FIG. 7 during a second time period;

fig. 10 and 11 are schematic structural diagrams of another head-up display system according to an embodiment of the invention;

FIG. 12 is a schematic optical path diagram of the heads-up display system shown in FIG. 10 during a second time period;

FIG. 13 is a schematic optical path diagram of the heads-up display system shown in FIG. 11 during a second time period;

fig. 14 and 15 are schematic optical path diagrams of a head-up display system according to an embodiment of the invention;

fig. 16 is a schematic structural diagram of another head-up display system according to an embodiment of the invention;

fig. 17 is a schematic structural diagram of another head-up display system according to an embodiment of the invention;

fig. 18 is a schematic structural diagram of another head-up display system according to an embodiment of the invention;

FIG. 19 is a schematic diagram illustrating a head-up display system according to an embodiment of the present invention;

FIG. 20 is a schematic diagram of a twisted nematic liquid crystal cell according to an embodiment of the present invention;

FIG. 21 is a schematic structural diagram of a twisted nematic liquid crystal cell after a predetermined voltage is applied between a first electrode plate and a second electrode plate;

fig. 22 is a schematic structural diagram of a head-up display system according to an embodiment of the invention;

FIG. 23 is a schematic diagram of another head-up display system according to an embodiment of the invention

Fig. 24 and 25 are schematic structural diagrams of another head-up display system according to an embodiment of the invention;

fig. 26 is a flowchart illustrating a driving method of a head-up display system according to an embodiment of the invention;

fig. 27 is a timing diagram of a control signal of a polarization state adjustment unit according to an embodiment of the present invention;

FIG. 28 is a timing diagram of a control signal of a polarization state adjustment unit according to an embodiment of the present invention;

fig. 29 is a timing diagram of a control signal of a polarization state adjustment unit according to an embodiment of the present invention;

FIG. 30 is a timing diagram of control signals of another polarization state adjustment unit according to an embodiment of the present invention;

FIG. 31 is a timing diagram of a control signal of a polarization state adjustment unit according to an embodiment of the present invention;

FIG. 32 is a timing diagram of control signals of another polarization state adjustment unit according to an embodiment of the present invention;

FIG. 33 is a timing diagram illustrating control signals of a polarization state adjustment unit according to an embodiment of the present invention;

fig. 34 is a timing diagram of a control signal of another polarization state adjustment unit according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. It should be noted that the terms "upper", "lower", "left", "right", and the like used in the description of the embodiments of the present invention are used in the angle shown in the drawings, and should not be construed as limiting the embodiments of the present invention. In addition, in this context, it is also to be understood that when an element is referred to as being "on" or "under" another element, it can be directly formed on "or" under "the other element or be indirectly formed on" or "under" the other element through an intermediate element. The terms "first," "second," and the like, are used for descriptive purposes only and not for purposes of limitation, and do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Fig. 1 is a schematic structural diagram of a head-up display system provided in the related art, and fig. 2 is a partially enlarged schematic view of fig. 1, and referring to fig. 1 and 2, a conventional head-up display system 3 includes a first display screen 31, a second display screen 32, a first reflecting mirror 33, and a second reflecting mirror 34. The first mirror 33 reflects the content displayed by the first display screen 31 to the second mirror 34 and further to the windshield 2 by the second mirror 34, so that the human eye 1 can see the first virtual image from the windshield 2. The content that second mirror 34 shows second display screen 32 directly reflects windshield 2, therefore people's eye 1 can see the second virtual image from windshield 2, and wherein the degree of depth of field of first virtual image and second virtual image is different, because windshield can also see through external light, the user can see two virtual images and the superimposed augmented reality AR effect of external environment light. However, the structure needs to be provided with two display screens, so that the occupied space is large and the cost is high.

Fig. 3 is a schematic structural diagram of another head-up display system provided in the related art, and referring to fig. 3, in another structure of a conventional head-up display system 3, the structure includes a first display screen 31, a second display screen 32, a first mirror 33, a second mirror 34, and a beam splitter 35. The beam splitter 35 includes a transparent substrate 351 and a reflective layer 352, wherein the reflective layer 352 has wavelength selectivity, the light emitted from the first display screen 31 can be reflected by the reflective layer 352, and the light emitted from the second display screen 32 can be transmitted by the reflective layer 352. The light emitted by the first display screen 31 is reflected by the first reflector 33, the beam splitter 35 and the second reflector 34 in sequence and then enters the windshield 2, so that the human eyes 1 can see a first virtual image from the windshield 2; light that second display screen 32 goes out is incided windshield 2 after 35 transmission of beam splitter and the reflection of second mirror 34, consequently people's eye 1 can see the second virtual image from windshield 2, and wherein the degree of depth of field of first virtual image and second virtual image is different, because windshield can also see through external light, the user can see two virtual images and the superimposed AR effect of external environment light. However, the above structure also needs to be provided with two display screens, and has limitations on the wavelength of light, which is easy to cause color cast.

In view of the foregoing problems, an embodiment of the present invention provides a head-up display system, which includes a control module, an image source module, a dimming module, a reflection module, and an imaging module, where the dimming module includes at least one polarization state adjustment unit and at least two metal wire grids, and the reflection module includes at least two reflectors; the image source module is electrically connected with the control module and is used for emitting imaging light under the control of the control module; the polarization state adjusting unit is electrically connected with the control module and is used for modulating the polarization state of the imaging light rays so as to enable the imaging light rays to be transmitted to the imaging module through the metal wire grating or enable the imaging light rays to be incident to the imaging module after being reflected by the metal wire grating and the reflector; the imaging module is used for transmitting imaging light to the windshield, and the windshield reflects the imaging light into human eyes for imaging.

Exemplarily, taking a dimming module including a polarization state adjusting unit and two metal wire grids, a reflection module including two reflection mirrors as an example, in other embodiments, the number of the metal wire grids and the reflection mirrors may be changed according to actual light path design requirements, fig. 4 is a schematic structural diagram of a head-up display system according to an embodiment of the present invention, referring to fig. 4, the head-up display system according to the embodiment includes a control module 10, an image source module 20, a dimming module 30, a reflection module 40, and an imaging module 50, where the dimming module 30 includes a polarization state adjusting unit 31, a metal wire grid 32, and a metal wire grid 33, and the reflection module 40 includes a reflection mirror 41 and a reflection mirror 42; the image source module 20 is electrically connected with the control module 10, and the image source module 20 is used for emitting imaging light under the control of the control module 10; the polarization state adjusting unit 31 is electrically connected to the control module 10, and the polarization state adjusting unit 31 is configured to modulate the polarization state of the imaging light, so that the imaging light a is transmitted to the imaging module 50 through the metal wire grid 32 and the metal wire grid 33, or the imaging light b is incident to the imaging module 50 after being reflected by the metal wire grid 32, the reflector 41, the reflector 42 and the metal wire grid 33; the imaging module 50 is used to transmit the imaging light to the windshield 60, and the windshield 60 reflects into the human eye 70 for imaging.

The control module 10 may include a single chip, a microcontroller, a microprocessor, or a computer, and any device or apparatus capable of satisfying the control function of the control module 10 may be used as the control module 10. The image source module 20 may include any display device for emitting imaging light such as graphics, text, or symbols. The embodiment of the present invention is not limited to a specific type, and any display device satisfying the above functions may be used as the image source module 20. For example, the display device may include a liquid crystal display LCD screen, an organic light emitting diode OLED screen, a mini-LED screen, or a micro-LED screen, etc., which can emit light, and may also be a digital light processing DLP display device using a projection principle. The metal wire grid 32 and the metal wire grid 33 are one type of grating formed by using a plurality of metal wires as grid wires, wherein the grid wires are opaque regions, a linear transparent region is included between two adjacent grid wires, the metal wire grid 32 and the metal wire grid 33 can reflect light with a polarization direction parallel to the extending direction of the grid wires and transmit light with a polarization direction perpendicular to the extending direction of the grid wires, in this embodiment, the polarization state adjusting unit 31 is configured to modulate the polarization state of the imaging light, for example, the imaging light can be modulated into different polarization directions at different times, so that the imaging light is reflected or transmitted when the imaging light enters the metal wire grid 32. In combination with the optical structure formed by the reflection module 40, the imaging light can form two paths of the imaging light a and the imaging light b shown in fig. 4, and two images with different depths of field are presented. The imaging module 50 may be a module for transmitting the imaging light a or the imaging light b to the windshield 60, and optionally, the imaging module 50 includes at least one spherical mirror, an aspherical mirror, or a free-form surface mirror, the spherical mirror, the aspherical mirror, or the free-form surface mirror reflects the light to the windshield 60, a surface radian of the aspherical mirror is different from a mirror surface radian of the spherical mirror, and the aspherical mirror may be a mirror surface whose curvature radius gradually increases or gradually decreases from a center to a periphery of the mirror surface. The free-form surface mirror may be a mirror surface with an irregular mirror surface arc. Different mirror surfaces can be selected according to actual needs so as to improve the display effect of the head-up display system. The embodiment of the present invention is not limited to a specific structure thereof, and any module that can satisfy the above conditions may be used as the imaging module 50. The image forming light ray a or the image forming light ray B is reflected by the windshield 60 to the human eye 70 to form a virtual image a and a virtual image B, respectively. Because the human eyes have the phenomenon of vision persistence, namely, when the image seen by the human eyes disappears for a period of time, the human eyes can still keep the image for 0.1 to 0.4 second. Therefore, the switching time of the imaging light ray a and the imaging light ray b in the period of each frame generated by the image source module 20 can be less than 0.4 second. And shorter switching time can be set according to actual needs to meet the requirement of visual persistence of human eyes. The user can form a virtual image with different depths of field on windshield 60 by alternately receiving imaging light ray a and imaging light ray b, and the virtual image and the external environment light transmitted by windshield 60 form an augmented reality display effect.

According to the technical scheme of the embodiment of the invention, imaging light rays are emitted under the control of the control module through the image source module; the polarization state of the imaging light is modulated by the polarization state adjusting unit, so that the imaging light is transmitted to the imaging module through the metal wire grid, or the imaging light is reflected by the metal wire grid and the reflector and then is incident to the imaging module, and the light of the two paths forms images with different depths of field; the imaging light is transmitted to the windshield through the imaging module, the windshield is reflected to enter human eyes for imaging, and therefore the head-up display effect of augmented reality is achieved through one imaging source and the dimming module, the size of the head-up display system is smaller, and the cost is lower.

On the basis of the foregoing embodiment, fig. 5 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, and referring to fig. 5, optionally, the dimming module 30 includes a first polarization state adjusting unit 311, a second polarization state adjusting unit 312, a first metal wire grid 32, and a second metal wire grid 33, and the reflection module 40 includes a first reflection mirror 41 and a second reflection mirror 42; the light emitting surface of the image source module 20 and the plane where the first polarization state adjusting unit 311 is located are both parallel to the first plane xoy, and the plane where the second polarization state adjusting unit 312 is located is perpendicular to the first plane xoy; the first metal wire grid 32 and the second metal wire grid 33 are located at two sides of the first polarization state adjusting unit 311, and a first included angle α is formed between a plane of the first metal wire grid 32 and the first plane xoy₁The plane of the second metal wire grid 33 and the first plane xoy form a second included angle α₂Wherein the first included angle alpha₁And a second angle alpha₂The light rays c transmitted through the first metal wire grid 32 are acute angles, and are transmitted through the first polarization state adjusting unit 311 and then enter the second metal wire grid 33; along the direction parallel to the first plane xoy, the reflection module 40 is located at a side of the second polarization state adjustment unit 312 far from the first metal wire grid 32, and the plane of the first reflection mirror 41 and the plane of the second polarization state adjustment unit 312 form a third included angle α₃The plane of the second reflector 42 and the plane of the second polarization state adjusting unit 312 form a fourth included angle α₄Wherein the third angle α₃And a fourth angle alpha₄The light d reflected by the first wire grid 32 is an acute angle, and is incident to the second wire grid 33 after being reflected by the first reflecting mirror 41 and the second reflecting mirror 42 in sequence.

Wherein the first polarization state adjusting unit 311 and the second polarization state adjusting unit 312 are vertically disposed, it is understood that the second polarization state adjusting unit 312 is disposed between the first metal wire grid 32 and the first mirror 41 only for illustration, and in other embodiments, the second polarization state adjusting unit 312 may be disposed between the second metal wire grid 33 and the second mirror 42, and the implementation can be selected according to actual situations. In specific implementation, optionally, the first included angle α₁And a second angle alpha₂Can be both set at 45 DEG and a third included angle alpha₃And a fourth angle alpha₄May be set to 10 deg. -80 deg., preferably 40 deg. -60 deg., to better match the angle of inclination of the windshield 60. In other embodiments, third included angle α may be set₃And a fourth angle alpha₄Satisfy the requirement of

Where n denotes the refractive index of the mirror and n₀Representing the refractive index of the medium (e.g. air or vacuum) between the second polarization state adjusting element and the mirror, such that the third angle alpha is₃And a fourth angle alpha₄The Brewster angle is satisfied, and p-polarized light can be prevented from being reflected to enter human eyes for imaging when the metal wire grating transmits light for imaging.

FIGS. 6 and 7 are diagrams illustrating a structure of another head-up display system according to an embodiment of the inventionAs shown in fig. 6 or fig. 7, alternatively, the extending directions of the grid lines of the first metal wire grid 32 and the second metal wire grid 33 are parallel (taking the grid lines of the metal wire grid along the x direction as an example, and not limiting the embodiment of the present invention), and the imaging light emitted from the image source module 20 includes polarized light of a first polarization direction (p-polarized light, dashed line indicates the same below) and polarized light of a second polarization direction (s-polarized light, solid line indicates the same below); in the first display time period t₁In the imaging module, the polarized light in the first polarization direction is transmitted by the first metal wire grid 32, the first polarization state adjusting unit 311, and the second metal wire grid 33 in sequence, then enters the imaging module 50, is transmitted to the windshield 60, is reflected, and then enters the human eyes 70 for imaging. Since the polarization direction of the p-polarized light is perpendicular to the grid lines of the first and second

metal wire grids

32 and 33, transmission occurs, and the first display period t₁In the meantime, the first polarization state adjustment unit 311 does not change the polarization state of the first polarization direction polarized light (p-polarized light), so that transmission occurs directly.

With reference to fig. 6, since the polarization direction of the s-polarized light is parallel to the extending direction of the grid lines of the first metal wire grid 32, the polarized light in the second polarization direction is reflected by the first metal wire grid 32 and then enters the second polarization state adjusting unit 312, the second polarization state adjusting unit 312 modulates the polarized light in the second polarization direction into the polarized light in the first polarization direction (s-polarized light → p-polarized light), and then the polarized light is reflected by the first reflecting mirror 41 and the second reflecting mirror 42 and then enters the second metal wire grid 32 for transmission, at this time, the light cannot be reflected by the windshield 60 and enter the human eye 70. Or referring to fig. 7, the polarized light in the second polarization direction is reflected by the first metal wire grid 32, the first reflector 41 and the second reflector 42 in sequence and then enters the second polarization state adjusting unit 312, the second polarization state adjusting unit modulates the polarized light in the second polarization direction into the polarized light in the first polarization direction (s-polarized light → p-polarized light), and then enters the second metal wire grid 33 for transmission, at this time, the light is not reflected by the windshield 60 and enters the human eye 70.

Fig. 8 is a schematic optical path diagram of the head-up display system shown in fig. 6 during a second time period, and fig. 9 is a schematic optical path diagram of the head-up display system shown in fig. 7 during the second time period, referring to fig. 8 or fig. 7FIG. 9, during the second display period t₂The polarized light in the second polarization direction sequentially passes through the first metal wire grid 32, the first reflecting mirror 41, the second reflecting mirror 42 and the second metal wire grid 33, is incident to the imaging module 50, and is transmitted to the windshield 60 to be reflected, and then enters the human eye 70 to be imaged, wherein the second polarization state adjusting unit 312 does not change the polarization state of the polarized light in the second polarization direction, and the second polarization state adjusting unit 312 is located on the light path between the first metal wire grid 32 and the first reflecting mirror 41 (fig. 8), or located on the light path between the second reflecting mirror 42 and the second metal wire grid 33 (fig. 9); the polarized light in the first polarization direction is transmitted by the first metal wire grid 32 and then enters the first polarization state adjusting unit 311, the first polarization state adjusting unit 311 modulates the polarized light in the first polarization direction into polarized light in the second polarization direction (p-polarized light → s-polarized light), and the polarized light enters the second metal wire grid 33 to be reflected, at this time, the light is not reflected by the windshield 60 and enters the human eye 70.

In other embodiments, the extending directions of the grid lines of the two metal wire grids can be parallel to the yoz plane, which is implemented similarly to the above embodiments, except that the paths of the first polarization direction polarized light and the second polarization direction polarized light are interchanged, and are not described in detail herein.

Fig. 10 and fig. 11 are schematic structural diagrams of another head-up display system according to an embodiment of the present invention, and referring to fig. 10 or fig. 11, optionally, directions of extending grid lines of the first metal wire grid 32 and the second metal wire grid 33 are perpendicular (taking the grid line of the first metal wire grid 32 along the x direction and the grid line of the second metal wire grid 33 parallel to the yoz plane as an example, but not limiting to the embodiment of the present invention), and the imaging light emitted from the image source module 20 includes a first polarization direction polarized light (p-polarized light) and a second polarization direction polarized light (s-polarized light); in the first display time period t₁In the imaging module, the polarized light in the first polarization direction is transmitted by the first metal wire grid 32 and then enters the first polarization state adjusting unit 311, the first polarization state adjusting unit 311 modulates the polarized light in the first polarization direction into the polarized light in the second polarization direction (p-polarized light → s-polarized light), and then enters the second metal wire grid 33 and then enters the imaging module 50 after being transmitted, and then is transmitted to the windshield 60 and reflected and enters the human eyes 70 to form the imaging moduleLike this. The polarization direction of the p-polarized light is perpendicular to the grid lines of the first metal wire grid 32, so that transmission occurs, the p-polarized light is converted into s-polarized light after being transmitted by the first polarization state control unit 311, and the polarization direction of the s-polarized light is perpendicular to the grid lines of the second metal wire grid 33, and the s-polarized light is transmitted to the imaging module 50 again.

With reference to fig. 10, since the polarization direction of the s-polarized light is parallel to the grid line direction of the first metal wire grid 32, the polarized light with the second polarization direction is incident on the second metal wire grid 33 and transmitted after being reflected by the first metal wire grid 32, the first reflector 41 and the second reflector 42 in sequence, and at this time, the light cannot be reflected by the windshield 60 and enter the human eye 70. The second polarization state adjusting unit 312 is positioned on the optical path between the first wire grid 32 and the first reflecting mirror 41 (fig. 10) or between the second reflecting mirror 42 and the second wire grid 33 (fig. 11).

Fig. 12 is a schematic optical path diagram of the head-up display system shown in fig. 10 during a second period of time, and fig. 13 is a schematic optical path diagram of the head-up display system shown in fig. 11 during the second period of time, referring to fig. 12, during a second display period t₂Meanwhile, the polarized light in the second polarization direction is reflected by the first metal wire grid 32 and then enters the second polarization state adjusting unit 312, the second polarization state adjusting unit 312 modulates the polarized light in the second polarization direction into the polarized light in the first polarization direction (s-polarized light → p-polarized light), then the polarized light in the second polarization direction sequentially reflects by the first reflector 41 and the second reflector 42 and then enters the second metal wire grid 33 to reflect and then enters the imaging module 50, and then the reflected light is transmitted to the windshield 60 to reflect and then enters the human eye 70 to image, or referring to fig. 13, the polarized light in the second polarization direction sequentially reflects by the first metal wire grid 32, the first reflector 41 and the second reflector 42 and then enters the second polarization state adjusting unit 312, the polarized light in the second polarization direction is modulated into the polarized light in the first polarization direction (s-polarized light → p-polarized light) and then enters the second metal wire grid 33 to reflect and then enters the imaging module 50, then transmitted to the windshield 60 to be reflected and enter the human eyes 70 for imaging; the polarized light of the first polarization direction is transmitted through the first metal wire grid 32 and the first polarization state adjusting unit 311, the first polarization state adjusting unit 311 does not change the polarization state of the light,the light is reflected by the second wire grid 33 and does not enter the human eye 70 through the windshield 60.

Cyclically repeating the first display period t₁And a second display period t₂The human eye can observe two images with different depths of field, wherein the switching time interval is lower than the resolution time of the human eye, and optionally,

in the head-up display system provided in the above embodiment, the imaging light emitted by the image source module includes p-polarized light and s-polarized light, and the specific imaging light may include natural light, circularly polarized light, or elliptically polarized light, and in other embodiments, the imaging light may also include linearly polarized light, for example, p-polarized light or s-polarized light. Exemplarily, taking the structure of the head-up display system shown in fig. 6 as an example, fig. 14 and fig. 15 are respectively a schematic optical path diagram of the head-up display system provided in the embodiment of the present invention, referring to fig. 14, when the imaging light emitted from the image source module 20 is p-polarized light, the first polarization state adjusting unit 311 does not change the polarization state of the light, and the p-polarized light sequentially passes through the first metal wire grid 32, the first polarization state adjusting unit 311 and the second metal wire grid 33, is incident to the imaging module 50 after being transmitted, is transmitted to the windshield 60, and then enters the human eye 70 for imaging; referring to fig. 15, when the imaging light emitted from the image source module 20 is s-polarized light, the second polarization state adjusting unit 312 does not change the polarization state of the light, and the s-polarized light is reflected by the first metal wire grid 32, the first reflecting mirror 41, the second reflecting mirror 42, and the second metal wire grid 33 in sequence, then enters the imaging module 50, is transmitted to the windshield 60, and then enters the human eye 70 for imaging. The two conditions are respectively equivalent to a conventional adjustable W-HUD (Windshield-HUD), the W-HUD utilizes the principle of optical reflection to project important driving related information on a Windshield for display, the display effect is more integrated, and the modeling arrangement is facilitated; however, because the windshield is generally curved glass, the W-HUD must be matched with a high-precision aspheric reflector according to the size and curvature of the windshield, and the cost of the W-HUD is higher, so that the head-up display system provided by the embodiment has a wider application range and adjustment range than a conventional structure, a better collimation effect and better image quality; compared with the AR-HUD of the previous embodiment, all light rays of the image source module can be used for imaging at the moment, no loss is wasted, and the polarization state adjusting unit can be omitted at the moment so as to reduce the cost. It can be understood that when the grid lines of the two metal wire grids are perpendicular, the polarization state of the light needs to be changed during the transmission of the light path, and therefore, the polarization state adjusting unit cannot be omitted.

Fig. 16 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, referring to fig. 16, optionally, the imaging light emitted by the image source module 20 includes linearly polarized light, the dimming module 30 further includes a third polarization state adjusting unit 313 disposed on the light emitting side of the image source module 20, and the third polarization state adjusting unit 313 is configured to modulate the linearly polarized light into polarized light in the first polarization direction or polarized light in the second polarization direction.

Illustratively, taking the structure shown in fig. 16 as an example, when the image source module 20 emits the polarized light of the first polarization direction (p-polarized light), the first display period t₁Meanwhile, the third polarization state adjustment unit 313 does not change the polarization state of the light (similar to the propagation of the light in fig. 14), and the imaging light is transmitted through the first metal wire grid 32, the first polarization state adjustment unit 311, and the second metal wire grid 33 in sequence, and is displayed for the second display period t₂In the meantime, the third polarization state adjustment unit 313 modulates the first polarization direction polarized light into the second polarization direction polarized light (p-polarized light → s-polarized light, similar to the propagation of light in fig. 15), and the imaging light is reflected by the first metal wire grid 32, the first mirror 41, the second mirror 42, and the second metal wire grid 33 in this order; when the image source module 20 emits the polarized light with the second polarization direction (s-polarized light), the display time t is the first display time period₁In the second display period t, the third polarization state adjustment unit 313 modulates the second polarization direction polarized light into the first polarization direction polarized light (s-polarized light → p-polarized light)₂In this embodiment, the third polarization state adjustment unit 313 does not change the polarization state of the light, and the first polarization state adjustment unit 311 and the second polarization state adjustment unit 312 may be omitted, and the first polarization state adjustment is performed when the grid lines of the two metal wire grids are perpendicularThe cell 311 and the second polarization state adjustment cell 312 cannot be omitted, and the polarization state of the light needs to be adjusted according to a specific process.

Optionally, the head-up display system provided in this embodiment further includes a moving module, where the moving module is configured to drive at least one of the image source module, the reflection module, and the imaging module to move, where a moving direction of the image source module is perpendicular to the first plane, a moving direction of the reflection module is perpendicular to the plane where the second polarization state adjustment unit is located, and a moving direction of the imaging module is rotation to adjust an imaging height.

For example, fig. 17 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, and referring to fig. 17, the head-up display system further includes a moving module 80, where the moving module 80 includes a first moving motor 81, a second moving motor 82, and a rotating motor 83, where the first moving motor 81 and the second moving motor 82 respectively drive the image source module 20 and the reflection module 40 to move in the arrow direction shown in the drawing to adjust the object distance, and the rotating motor 83 drives the imaging module 50 to rotate to adjust the height of the image, in other embodiments, one or two of the first moving motor 81, the second moving motor 82, and the rotating motor 83 may be further provided, and in specific implementation, may be selected according to actual situations.

Fig. 18 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, and referring to fig. 18, optionally, the reflection module 40 further includes a light absorbing layer 43, the light absorbing layer 43 is located at a gap between the first reflection mirror 41 and the second reflection mirror 42, a projection of the light absorbing layer 43 on a second plane xoz covers a projection of the first polarization state adjustment unit 311 on a second plane xoz, and the second plane xoz is perpendicular to the first plane xoy.

The light absorbing layer 43 may be a black flannelette, the length of the black flannelette is the same as the length of the first reflector 41, and the width of the black flannelette is not less than the width of the first polarization adjusting unit 311, for example, the width of the black flannelette is the same as the width of the first polarization adjusting unit 311, so as to ensure that stray light is not reflected to cause image quality degradation.

Fig. 19 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, referring to fig. 19, optionally, the head-up display system according to the embodiment further includes a housing 90, the control module 10, the image source module 20, the dimming module 30, the reflection module 40, and the imaging module 50 are all disposed in the housing 90, and the housing 90 is provided with a light-transmitting window 901, where the light-transmitting window 901 is used for transmitting imaging light transmitted from the imaging module 50 to the windshield 60.

The housing 90 may be made of black high temperature resistant plastic material to absorb light interfering with imaging. The light-transmissive window 901 may be a window formed on the case. In other embodiments, the light-transmitting window 901 may be provided with a transparent cover plate, the transparent cover plate may be made of flexible materials such as plastic and resin, and optionally, the incident surface and/or the exit surface of the light-transmitting window 901 may be provided with an antireflection film, so as to reduce light energy loss and improve an imaging effect.

Optionally, the polarization state adjustment unit comprises a twisted nematic liquid crystal cell or an electrically controlled birefringent liquid crystal cell.

The twisted nematic liquid crystal cell and the electric control birefringence liquid crystal cell have similar substrate structures, and the adjustment of the polarization state of light is realized by changing the arrangement mode of liquid crystal molecules by applying an electric field. Exemplarily, taking a twisted nematic liquid crystal cell as an example, fig. 20 is a schematic structural diagram of a twisted nematic liquid crystal cell according to an embodiment of the present invention, and referring to fig. 20, the twisted nematic liquid crystal cell includes a first electrode plate 100, a second electrode plate 200, and a liquid crystal layer 300. Under an initial condition, liquid crystal molecules in the liquid crystal layer 300 are arranged in a twisted manner, for example, in a manner of being rotated by 90 ° from bottom to top, and when no voltage is applied between the first electrode plate 100 and the second electrode plate 200, the polarization state of light transmitted through the twisted nematic liquid crystal cell is rotated by 90 °; when a preset voltage is applied between the first electrode plate 100 and the second electrode plate 200, fig. 21 is a schematic structural diagram of the twisted nematic liquid crystal cell after the preset voltage is applied between the first electrode plate and the second electrode plate, liquid crystal molecules deflect under the action of an electric field, and when the preset voltage just enables the liquid crystal molecules to be arranged in parallel, the polarization state of light rays is not changed when the light rays are transmitted through the twisted nematic liquid crystal cell, wherein the magnitude of the preset voltage is determined according to actual conditions. When the polarization state adjusting unit is an electrically controlled birefringence ECB cell, the optical principle is similar to that of a twisted nematic liquid crystal cell, except that the electrically controlled birefringence effect of the liquid crystal is used to change the polarization state of light. It should be noted that the electrodes for controlling the liquid crystal molecule deflection shown in fig. 20 are only schematically located at the upper and lower sides, and in other embodiments, two electrodes may be disposed on the same side of the liquid crystal layer to form a liquid crystal cell similar to an in-plane switching IPS.

Optionally, the grating period range of the metal wire grid is 1nm to 200 nm.

Wherein the grating period is the length from one refractive index change point to another refractive index change point adjacent thereto. The metal wire grids with different grating periods can be selected according to actual needs, and then the polarized light in the first polarization direction and the polarized light in the second polarization direction are well separated. In this embodiment, the grating period range of the metal wire grid is 1nm to 200nm, and further optionally, the grating period range of the metal wire grid is 40nm to 80 nm. The effect is better when the grating period is one tenth of the light wavelength, and the range of visible light is about 400nm-800nm because the head-up display system utilizes visible light for imaging, so the grating period range of the metal wire grating is 40 nm-80 nm.

The embodiment of the invention also provides a head-up display system, which comprises a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least two metal wire grids, and the reflection module comprises at least two reflectors; the image source module is electrically connected with the control module, the image source module comprises a display unit and a polarization state adjusting unit positioned on the light emitting side of the display unit, the display unit is used for emitting imaging light under the control of the control module, and the polarization state adjusting unit is used for modulating the polarization state of the imaging light so as to enable the imaging light to be transmitted to the imaging module through the metal wire grating or enable the imaging light to be incident to the imaging module after being reflected by the metal wire grating and the reflector; the imaging module is used for transmitting imaging light to the windshield, and the windshield reflects the imaging light into human eyes for imaging.

For example, taking two metal wire grids of a dimming module and two reflecting mirrors as an example, in other embodiments, the number of the metal wire grids and the reflecting mirrors may be changed according to actual light path design requirements, fig. 22 is a schematic structural diagram of a head-up display system according to an embodiment of the present invention, referring to fig. 22, the head-up display system according to this embodiment includes a control module 10, an image source module 20, a dimming module 30, a reflecting module 40, and an imaging module 50, where the dimming module 30 includes a metal wire grid 32 and a metal wire grid 33, and the reflecting module 40 includes a reflecting mirror 41 and a reflecting mirror 42; the image source module 20 is electrically connected with the control module 10, the image source module 20 includes a display unit 21 and a polarization state adjusting unit 22 located at the light emitting side of the display unit 21, and the display unit 21 is used for emitting imaging light under the control of the control module 10; the polarization state adjusting unit 22 is configured to modulate the polarization state of the imaging light, so that the imaging light a is transmitted to the imaging module 50 through the metal wire grid 32 and the metal wire grid 33, or the imaging light b is incident to the imaging module 50 after being reflected by the metal wire grid 32, the reflecting mirror 41, the reflecting mirror 42 and the metal wire grid 33; the imaging module 50 is used to transmit the imaging light to the windshield 60, and the windshield 60 reflects into the human eye 70 for imaging.

The control module 10 may include a single chip, a microcontroller, a microprocessor, or a computer, and any device or apparatus capable of satisfying the control function of the control module 10 may be used as the control module 10. The display unit 21 may include any display device for emitting imaging light such as graphics, letters, or symbols. The embodiment of the present invention is not limited to a specific type thereof, and any display device satisfying the above-described functions may be used as the display unit 21. For example, the display device may include a liquid crystal display LCD screen, an organic light emitting diode OLED screen, a mini-LED screen, or a micro-LED screen, etc., which can emit light, and may also be a digital light processing DLP display device using a projection principle. The metal wire grid 32 and the metal wire grid 33 are one type of grating formed by using a plurality of metal wires as grid wires, wherein the grid wires are opaque regions, a linear transparent region is included between two adjacent grid wires, the metal wire grid 32 and the metal wire grid 33 can reflect light with a polarization direction parallel to the extending direction of the grid wires and transmit light with a polarization direction perpendicular to the extending direction of the grid wires, in this embodiment, the polarization state adjusting unit 22 is configured to modulate the polarization state of the imaging light, for example, the imaging light can be modulated into different polarization directions at different times, so that the imaging light is reflected or transmitted when the imaging light enters the metal wire grid 32. In conjunction with the optical structure formed by the reflective module 40, the imaging light can form two paths, namely, the imaging light a and the imaging light b shown in fig. 22, and two images with different depths of field are presented. The imaging module 50 may be a module for transmitting the imaging light a or the imaging light b to the windshield 60, and optionally, the imaging module 50 includes at least one spherical mirror, an aspherical mirror, or a free-form surface mirror, the spherical mirror, the aspherical mirror, or the free-form surface mirror reflects the light to the windshield 60, a surface radian of the aspherical mirror is different from a mirror surface radian of the spherical mirror, and the aspherical mirror may be a mirror surface whose curvature radius gradually increases or gradually decreases from a center to a periphery of the mirror surface. The free-form surface mirror may be a mirror surface with an irregular mirror surface arc. Different mirror surfaces can be selected according to actual needs so as to improve the display effect of the head-up display system. The embodiment of the present invention is not limited to a specific structure thereof, and any module that can satisfy the above conditions may be used as the imaging module 50. The imaging light ray a or the imaging light ray b is reflected by the windshield 60 to the human eye 70. Because the human eyes have the phenomenon of vision persistence, namely, when the image seen by the human eyes disappears for a period of time, the human eyes can still keep the image for 0.1 to 0.4 second. Therefore, the switching time of the imaging light ray a and the imaging light ray b in the period of each frame generated by the image source module 20 can be less than 0.4 second. And shorter switching time can be set according to actual needs to meet the requirement of visual persistence of human eyes. The user can form virtual images of different depths of field that formation of image light a and formation of image light B received in turn on windshield 60, form virtual image A and virtual image B respectively and windshield 60 transmission's external environment light forms augmented reality's display effect.

According to the technical scheme of the embodiment of the invention, the imaging light rays are emitted out through the display unit under the control of the control module; the polarization state of the imaging light is modulated by the polarization state adjusting unit, so that the imaging light is transmitted to the imaging module through the metal wire grid, or the imaging light is reflected by the metal wire grid and the reflector and then is incident to the imaging module, and the light of the two paths forms images with different depths of field; the imaging light is transmitted to the windshield through the imaging module, the windshield is reflected to enter human eyes for imaging, and therefore the head-up display effect of augmented reality is achieved through one imaging source and the dimming module, the volume of the head-up display system is smaller, and the cost is lower.

It is understood that the difference between the embodiment of the present invention and the embodiment in fig. 4 is that the polarization state adjustment unit 22 is located in the image source module 20, and may be integrated with the display unit 21 or may be separately provided in the embodiment of the present invention, which is not limited thereto. In other embodiments, structures such as a moving module, a light absorbing layer, and a housing may also be provided, the polarization state adjusting unit may include a twisted nematic liquid crystal cell or an electrically controlled birefringence liquid crystal cell, and parameters such as a grating period of the metal wire grid may also be the same as those in the foregoing embodiments, and may be designed according to actual situations when implemented specifically.

On the basis of the foregoing embodiment, fig. 23 is a schematic structural diagram of another head-up display system according to an embodiment of the present invention, referring to fig. 23, optionally, the dimming module 30 includes a first metal wire grid 32 and a second metal wire grid 33, and the reflection module 40 includes a first reflection mirror 41 and a second reflection mirror 42; the light emitting surface of the display unit 21 is parallel to the first plane xoy, the first metal wire grids 32 and the second metal wire grids 33 are sequentially arranged along the side far away from the display unit 21 along the direction perpendicular to the first plane xoy, and the plane where the first metal wire grids 32 are located and the first plane xoy form a first included angle alpha₁The plane of the second metal wire grid 33 and the first plane xoy form a second included angle α₂Wherein the first included angle alpha₁And a second angle alpha₂Are all acute angles, and the light ray c transmitted through the first wire grid 32 is incident to the second wire grid 33; the first reflector 41 and the second reflector 42 are arranged in sequence along a side away from the display unit 21 in a direction parallel to the first plane xoy, the plane of the first reflector 41 and the second plane xoz form a third included angle alpha₃The plane of the second reflecting mirror 42 forms a fourth angle alpha with the second plane xoz₄Wherein the first plane xoy is perpendicular to the second plane xoz, and the third angle alpha is₃And a fourth angle alpha₄The light d reflected by the first wire grid 32 is incident on the second wire grid 3 after being reflected by the first reflector 41 and the second reflector 42 in sequence3。

In specific implementation, optionally, the first included angle α₁And a second angle alpha₂Can be both set at 45 DEG and a third included angle alpha₃And a fourth angle alpha₄May be set to 10 deg. -80 deg., preferably 40 deg. -60 deg., to better match the angle of inclination of the windshield 60. In other embodiments, third included angle α may be set₃And a fourth angle alpha₄Satisfy the requirement of

Where n denotes the refractive index of the mirror and n₀Representing the refractive index of the medium (e.g. air or vacuum) between the second polarization state adjusting element and the mirror, such that the third angle alpha is₃And a fourth angle alpha₄The Brewster angle is satisfied, and light rays which do not need imaging can be prevented from reflecting to enter human eyes for imaging when the metal wire grating transmits light rays for imaging.

Fig. 24 and 25 are schematic structural diagrams of another head-up display system according to an embodiment of the invention, and referring to fig. 24 or 25, optionally, the dimming module 30 further includes a first polarization state adjusting unit 311 and a second polarization state adjusting unit 312, a plane of the first polarization state adjusting unit 311 is parallel to the first plane xoy, a plane of the second polarization state adjusting unit 312 is perpendicular to the first plane xoy, the first polarization state adjusting unit 311 is located between the first metal wire grid 32 and the second metal wire grid 33, the light transmitted through the first metal wire grid 32 is transmitted by the first polarization state adjusting unit 311 and then enters the second metal wire grid 33, and the second polarization state adjusting unit 312 is located on an optical path between the first metal wire grid 32 and the first reflector 41 (fig. 24) or an optical path between the second metal wire grid 33 and the second reflector 42 (fig. 25).

It is understood that the working principle and the working process of the head-up display system provided in the present embodiment are similar to those of the previous embodiments, wherein the embodiment of fig. 23 is suitable for the case that the display unit 21 emits linearly polarized light, and the details are not described here.

The embodiment of the present invention further provides a driving method of a head-up display system, which is applicable to any one of the head-up display systems provided in the embodiments, where the head-up display system includes a control module, an image source module, a dimming module, a reflection module and an imaging module, the dimming module includes at least one polarization state adjustment unit and at least two metal wire grids, the reflection module includes at least two reflectors, or the image source module includes a display unit and a polarization state adjustment unit located on a light exit side of the display unit, the dimming module includes at least two metal wire grids, and the reflection module includes at least two reflectors. Fig. 26 is a schematic flowchart of a driving method of a head-up display system according to an embodiment of the present invention, and referring to fig. 26, the driving method according to the embodiment includes:

and S110, the control module controls the image source module to emit imaging light.

The control module may include a single chip microcomputer, a microcontroller, a microprocessor, a running computer, or the like, the image source module may include any display device for emitting imaging light such as graphics, characters, symbols, or the like, the imaging light may be natural light or polarized light (for example, circularly polarized light, elliptically polarized light, or linearly polarized light) according to needs, and the imaging light may be selected according to actual needs in specific implementation.

Step S120, the polarization state adjusting unit modulates the polarization state of the imaging light so as to enable the imaging light to be in the first display time period t₁The imaging light is transmitted to the imaging module through the metal wire grating so as to enable the imaging light to be in the second display time period t₂The inside of the imaging module is reflected by the metal wire grid and the reflector and then enters the imaging module.

By alternately performing the first display period t₁And a second display period t₂Human eyes can see two virtual images with different depths of field on the windshield, and the two virtual images and external environment light transmitted by the windshield form an augmented reality display effect.

Optionally, the dimming module includes a first polarization state adjusting unit, a second polarization state adjusting unit, a first metal wire grid and a second metal wire grid, the reflection module includes a first reflector and a second reflector, the extending directions of the grid wires of the first metal wire grid and the second metal wire grid are parallel, and the imaging light emitted from the image source module includes a first polarization direction polarized light and a second polarization direction polarized lightThe polarization directions of the polarized light with the first polarization direction and the polarized light with the second polarization direction are vertical; in the first display time period t₁The first polarization state adjusting unit loads a first voltage signal, and the second polarization state adjusting unit loads a second voltage signal; in the second display period t₂The first polarization state adjusting unit loads a second voltage signal, and the second polarization state adjusting unit loads a first voltage signal; the first polarization state adjusting unit or the second polarization state adjusting unit enables light to be directly transmitted when the first voltage signal is loaded, and the polarization direction of the light is rotated by 90 degrees when the second voltage signal is loaded by the first polarization state adjusting unit or the second polarization state adjusting unit.

Exemplarily, for the embodiment in fig. 6, taking the polarization state adjustment unit as a twisted nematic liquid crystal cell as an example, fig. 27 is a timing diagram of a control signal of the polarization state adjustment unit according to the embodiment of the present invention, and referring to fig. 27, in a first display time period t₁In the above, the first polarization state adjusting unit loads the first voltage signal (high level signal), and the second polarization state adjusting unit loads the second voltage signal (low level signal), and the optical path process is as shown in fig. 6; in the second display period t₂In the above embodiment, the first polarization state adjusting unit loads the second voltage signal (low level signal), and the second polarization state adjusting unit loads the first voltage signal (high level signal), and the optical path process is as shown in fig. 8.

Optionally, the dimming module includes a first polarization state adjusting unit, a second polarization state adjusting unit, a first metal wire grid and a second metal wire grid, the reflection module includes a first reflector and a second reflector, the extending directions of grid wires of the first metal wire grid and the second metal wire grid are perpendicular, the imaging light emitted from the image source module includes polarized light in the first polarization direction and polarized light in the second polarization direction, and the polarization directions of the polarized light in the first polarization direction and the polarized light in the second polarization direction are perpendicular; in the first display time period t₁The first polarization state adjusting unit loads a second voltage signal, and the second polarization state adjusting unit loads a first voltage signal; in the second display period t₂In the first polarization state adjusting unit, a first voltage signal is loaded, and a second voltage signal is loadedThe polarization state adjusting unit loads a second voltage signal; the first polarization state adjusting unit or the second polarization state adjusting unit enables light to be directly transmitted when the first voltage signal is loaded, and the polarization direction of the light is rotated by 90 degrees when the second voltage signal is loaded by the first polarization state adjusting unit or the second polarization state adjusting unit.

For the embodiment in fig. 10, taking the polarization state adjustment unit as the twisted nematic liquid crystal cell as an example, fig. 28 is a timing diagram of a control signal of the polarization state adjustment unit provided by the embodiment of the invention, referring to fig. 28, during the first display time period t₁In the above, the first polarization state adjusting unit loads the second voltage signal, the second polarization state adjusting unit loads the first voltage signal, and the optical path process is as shown in fig. 10; in the second display period t₂In the above, the first polarization state adjusting unit loads the first voltage signal, and the second polarization state adjusting unit loads the second voltage signal, and the optical path process is as shown in fig. 12.

Optionally, the image source module includes a display unit and a polarization state adjustment unit located on a light exit side of the display unit, the dimming module includes a first metal wire grid and a second metal wire grid, extension directions of grid wires of the first metal wire grid and the second metal wire grid are parallel, the reflection module includes a first reflector and a second reflector, and the display unit emits linearly polarized light; when the polarization direction of linearly polarized light emitted from the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, for a first display period t₁The polarization state adjusting unit loads a second voltage signal and displays for a second display time period t₂The polarization state adjusting unit loads a first voltage signal; when the polarization direction of linearly polarized light emitted from the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, for a first display period t₁In the second display time period t, the polarization state adjusting unit loads the first voltage signal₂The polarization state adjusting unit loads a second voltage signal; the polarization state adjusting unit enables light rays to be directly transmitted when the first voltage signal is loaded, and enables the polarization direction of the light rays to rotate by 90 degrees when the second voltage signal is loaded.

For that in FIG. 23In an embodiment, when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, fig. 29 is a timing diagram of a control signal of a polarization state adjusting unit according to an embodiment of the present invention, and referring to fig. 29, in a first display time period t₁And the polarization state adjusting unit loads a second voltage signal to rotate the polarization direction of the light ray by 90 degrees, the light ray is transmitted by the first metal wire grid and is displayed for a second display time period t₂The polarization state adjusting unit loads a first voltage signal, the polarization direction of light is not changed, and the light is reflected by the first metal wire grid; when the polarization direction of the linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, fig. 30 is a timing diagram of a control signal of another polarization state adjusting unit according to an embodiment of the present invention, and referring to fig. 30, in a first display time period t₁The polarization state adjusting unit loads a first voltage signal, the polarization direction of light is not changed, the light is transmitted in the first metal wire grid, and the second display time period t₂And the polarization state adjusting unit loads a second voltage signal to rotate the polarization direction of the light ray by 90 degrees, and the light ray is reflected by the first metal wire grid.

Optionally, the dimming module further includes a first polarization state adjusting unit and a second polarization state adjusting unit, the first polarization state adjusting unit is located between the first metal wire grid and the second metal wire grid, and the second polarization state adjusting unit is located on the light path between the first metal wire grid and the first reflector or on the light path between the second metal wire grid and the second reflector; when the polarization direction of linearly polarized light emitted from the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, for a first display period t₁The first polarization state adjusting unit loads a first voltage signal (at this time, the second polarization state adjusting unit can load the first voltage signal or a second voltage signal); in the second display period t₂The second polarization state adjusting unit loads the first voltage signal (at this time, the first polarization state adjusting unit can load the first voltage signal or the second voltage signal); when the polarization direction of the linearly polarized light emitted by the display unit is vertical to the extending direction of the grid lines of the first metal wire gridAt a first display time period t₁The first polarization state adjusting unit loads a second voltage signal (at this time, the second polarization state adjusting unit can load the first voltage signal or the second voltage signal); in the second display period t₂In this case, the second polarization state adjustment unit may load the first voltage signal or the second voltage signal).

Exemplarily, for the embodiment in fig. 24, when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, fig. 31 is a timing diagram of a control signal of a polarization state adjusting unit according to an embodiment of the present invention, and when the polarization direction of the linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, fig. 32 is a timing diagram of a control signal of another polarization state adjusting unit according to an embodiment of the present invention.

It can be understood that, when the dimming module further includes the first polarization state adjusting unit and the second polarization state adjusting unit, the first polarization state adjusting unit and the second polarization state adjusting unit do not change the polarization direction of the light when functioning, so that the first polarization state adjusting unit and the second polarization state adjusting unit may be optional, and the first polarization state adjusting unit and the second polarization state adjusting unit may be always loaded with the first voltage signal to reduce the number of level changes, or the polarization state adjusting unit that needs to be directly transmitted loads the first voltage signal and the other loads the second voltage signal to reduce the power consumption.

Optionally, the image source module includes a display unit and a polarization state adjusting unit located on a light emitting side of the display unit, the dimming module includes a first polarization state adjusting unit, a second polarization state adjusting unit, a first metal wire grid and a second metal wire grid, extension directions of grid wires of the first metal wire grid and the second metal wire grid are perpendicular, the reflection module includes a first reflector and a second reflector, and linearly polarized light is emitted from the display unit; when the polarization direction of linearly polarized light emitted from the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, for a first display period t₁Internal and polarization state modulationThe node unit and the first polarization state adjusting unit are loaded with a second voltage signal and are in a second display time period t₂The polarization state adjusting unit loads a first voltage signal, and the second polarization state adjusting unit loads a second voltage signal; when the polarization direction of linearly polarized light emitted from the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, for a first display period t₁In the display device, the polarization state adjusting unit loads a first voltage signal, the first polarization state adjusting unit loads a second voltage signal (at this time, the second polarization state adjusting unit can load the first voltage signal or the second voltage signal), and the display device is configured to display the second display time period t₂The polarization state adjusting unit loads a second voltage signal, and the second polarization state adjusting unit loads a second voltage signal (at this time, the second polarization state adjusting unit can load the first voltage signal or the second voltage signal); the polarization state adjusting unit, the first polarization state adjusting unit or the second polarization state adjusting unit directly transmits light when the first voltage signal is loaded, and the polarization direction of the light rotates by 90 degrees when the second voltage signal is loaded.

It can be understood that, when the extending directions of the grid lines of the two metal wire grids are perpendicular, the first polarization state adjusting unit and the second polarization state adjusting unit cannot be omitted, when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, fig. 33 is a timing diagram of a control signal of one polarization state adjusting unit provided by the embodiment of the present invention, and when the polarization direction of the linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, fig. 34 is a timing diagram of a control signal of another polarization state adjusting unit provided by the embodiment of the present invention.

The embodiment of the invention also provides a vehicle which comprises any one of the head-up display systems provided by the embodiments, wherein the vehicle can be a vehicle such as an automobile and an airplane which is provided with a transparent windshield.

The vehicle provided by the embodiment of the invention comprises the head-up display system provided by any embodiment of the invention, and has the same or corresponding beneficial effects of the head-up display system.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A head-up display system is characterized by comprising a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least one polarization state adjusting unit and at least two metal wire grids, and the reflection module comprises at least two reflectors;

2. The head-up display system according to claim 1, wherein the dimming module comprises a first polarization state adjustment unit, a second polarization state adjustment unit, a first metal wire grid and a second metal wire grid, and the reflection module comprises a first reflection mirror and a second reflection mirror;

the light emitting surface of the image source module and the plane of the first polarization state adjusting unit are both parallel to a first plane, and the plane of the second polarization state adjusting unit is perpendicular to the first plane;

the first metal wire grid and the second metal wire grid are positioned at two sides of the first polarization state adjusting unit, the plane where the first metal wire grid is positioned and the first plane form a first included angle, the plane where the second metal wire grid is positioned and the first plane form a second included angle, the first included angle and the second included angle are acute angles, and light transmitted by the first metal wire grid is transmitted by the first polarization state adjusting unit and then enters the second metal wire grid;

the edge is on a parallel with in the direction at first plane place, reflection module is located second polarization state regulating unit keeps away from first metal wire grid one side, first speculum place plane with second polarization state regulating unit place plane is the third contained angle, second speculum place plane with second polarization state regulating unit place plane is the fourth contained angle, wherein the third contained angle with the fourth contained angle is the acute angle, process the light that first metal wire grid reflects passes through in proper order first speculum with incidenting extremely after the second speculum reflects second metal wire grid.

3. The head-up display system according to claim 2, wherein the first and second metal wire grids have grid wires extending in parallel, and the image light emitted from the image source module includes first and second polarization-direction polarized lights;

in the first display time period t₁The polarized light in the first polarization direction is transmitted by the first metal wire grid, the first polarization state adjusting unit and the second metal wire grid in sequence, then is incident to the imaging module, is transmitted to the windshield, is reflected and then enters human eyes for imaging;

the polarized light in the second polarization direction is reflected by the first metal wire grid and then enters the second polarization state adjusting unit, the polarized light in the second polarization direction is modulated into polarized light in the first polarization direction by the second polarization state adjusting unit, and then is reflected by the first reflector and the second reflector in sequence and then enters the second metal wire grid for transmission, or the polarized light in the second polarization direction is reflected by the first metal wire grid, the first reflector and the second reflector in sequence and then enters the second polarization state adjusting unit, and the polarized light in the second polarization direction is modulated into polarized light in the first polarization direction by the second polarization state adjusting unit and then enters the second metal wire grid for transmission;

in the second display period t₂The polarized light in the second polarization direction sequentially passes through the first metal wire grid, the first reflector, the second reflector and the second metal wire grid, is reflected and then enters the imaging module, is transmitted to the windshield, is reflected and then enters human eyes for imaging, and the second polarization state adjusting unit is positioned on a light path between the first metal wire grid and the first reflector or positioned on a light path between the second reflector and the second metal wire grid;

the polarized light in the first polarization direction is transmitted by the first metal wire grid and then enters the first polarization state adjusting unit, and the first polarization state adjusting unit modulates the polarized light in the first polarization direction into polarized light in a second polarization direction and then enters the second metal wire grid for reflection.

4. The head-up display system according to claim 2, wherein the first metal wire grid and the second metal wire grid extend in a vertical direction, and the image light emitted from the image source module comprises a first polarization direction polarized light and a second polarization direction polarized light;

in the first display time period t₁The first polarization direction polarized light is transmitted by the first metal wire grid and then enters the first polarization state adjusting unit, and the first polarization state adjusting unit modulates the first polarization direction polarized light into second polarization direction polarized light and then enters the second polarization direction polarized lightThe second metal wire grid is transmitted and then enters the imaging module, and then is transmitted to the windshield to be reflected and enters human eyes to be imaged;

the polarized light in the second polarization direction is reflected by the first metal wire grid, the first reflector and the second reflector in sequence and then enters the second metal wire grid for transmission, and the second polarization state adjusting unit is located on the light path between the first metal wire grid and the first reflector or the light path between the second reflector and the second metal wire grid;

in the second display period t₂The second polarization direction polarized light is incident to the second polarization state adjusting unit after being reflected by the first metal wire grid, the second polarization state adjusting unit modulates the second polarization direction polarized light into first polarization direction polarized light, the first polarized light is incident to the second metal wire grid after being reflected by the first reflector and the second reflector in sequence and then is incident to the imaging module after being reflected by the second metal wire grid, the second polarization direction polarized light is transmitted to the windshield and then enters human eyes for imaging, or the second polarization direction polarized light is incident to the second polarization state adjusting unit after being reflected by the first metal wire grid, the first reflector and the second reflector in sequence, the second polarization state adjusting unit modulates the second polarization direction polarized light into first polarization direction polarized light, and then is incident to the imaging module after being reflected by the second metal wire grid, then the image is transmitted to the windshield to be reflected and enters human eyes for imaging;

the polarized light with the first polarization direction is transmitted by the first metal wire grid and the first polarization state adjusting unit and then enters the second metal wire grid to be reflected.

5. The head-up display system of claim 3 or 4,

6. the head-up display system according to claim 2, wherein the imaging light emitted from the image source module includes linearly polarized light, the dimming module further includes a third polarization state adjusting unit disposed on the light emitting side of the image source module, and the third polarization state adjusting unit is configured to modulate the linearly polarized light into polarized light in the first polarization direction or polarized light in the second polarization direction.

7. The head-up display system according to claim 2, further comprising a moving module, configured to drive at least one of the image source module, the reflection module and the imaging module to move, wherein the moving direction of the image source module is perpendicular to the first plane, the moving direction of the reflection module is perpendicular to the plane where the second polarization state adjustment unit is located, and the moving direction of the imaging module is rotation to adjust the imaging height.

8. The heads-up display system of claim 2 wherein the third angle is in a range of 10 ° to 80 ° and the fourth angle is in a range of 10 ° to 80 °.

9. The heads-up display system of claim 2 wherein the reflection module further comprises a light absorbing layer located at the gap between the first mirror and the second mirror, a projection of the light absorbing layer on a second plane overlaying a projection of the first polarization state adjustment unit on the second plane, the second plane being perpendicular to the first plane.

10. The head-up display system of claim 1, further comprising a housing, wherein the control module, the image source module, the dimming module, the reflection module, and the imaging module are disposed in the housing, and the housing is provided with a light transmissive window for transmitting imaging light transmitted from the imaging module to the windshield.

11. The head-up display system of claim 10, wherein the entrance face and/or the exit face of the light transmissive window is provided with an antireflection film.

12. The heads-up display system of claim 1, wherein the polarization state adjustment unit comprises a twisted nematic liquid crystal cell or an electrically controlled birefringent liquid crystal cell.

13. The heads-up display system of claim 1 wherein the metal wire grid has a grating period in a range of 1nm to 200 nm.

14. The heads-up display system of claim 1 wherein the imaging module comprises at least one of a spherical mirror, an aspherical mirror, or a freeform mirror.

15. A head-up display system is characterized by comprising a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least two metal wire grids, and the reflection module comprises at least two reflectors;

16. The heads-up display system of claim 15 wherein the dimming module comprises a first wire grid and a second wire grid, the reflective module comprises a first mirror and a second mirror;

the light emitting surface of the display unit is parallel to a first plane, the first metal wire grids and the second metal wire grids are sequentially arranged along one side far away from the display unit along the direction perpendicular to the first plane, the plane where the first metal wire grids are located and the first plane form a first included angle, the plane where the second metal wire grids are located and the first plane form a second included angle, the first included angle and the second included angle are acute angles, and imaging light transmitted by the first metal wire grids is incident to the second metal wire grids;

the first reflector and the second reflector are sequentially arranged along the direction parallel to the first plane, a third included angle is formed between the plane where the first reflector is located and the second plane, a fourth included angle is formed between the plane where the second reflector is located and the second plane, the first plane is perpendicular to the second plane, the third included angle and the fourth included angle are acute angles, and imaging light reflected by the first metal wire grid sequentially passes through the first reflector and the second reflector and then enters the second metal wire grid after being reflected.

17. The head-up display system according to claim 16, wherein the dimming module further comprises a first polarization state adjusting unit and a second polarization state adjusting unit, the first polarization state adjusting unit is located in a plane parallel to the first plane, the second polarization state adjusting unit is located in a plane perpendicular to the first plane, the first polarization state adjusting unit is located between the first metal wire grid and the second metal wire grid, the light transmitted through the first metal wire grid is transmitted by the first polarization state adjusting unit and then enters the second metal wire grid, and the second polarization state adjusting unit is located on an optical path between the first metal wire grid and the first reflector or an optical path between the second metal wire grid and the second reflector.

18. The driving method of the head-up display system is characterized in that the head-up display system comprises a control module, an image source module, a dimming module, a reflection module and an imaging module, wherein the dimming module comprises at least one polarization state adjusting unit and at least two metal wire grids, the reflection module comprises at least two reflectors, or the image source module comprises a display unit and a polarization state adjusting unit positioned on the light emitting side of the display unit, the dimming module comprises at least two metal wire grids, and the reflection module comprises at least two reflectors; the driving method includes:

the control module controls the image source module to emit imaging light;

the polarization state adjusting unit modulates the polarization state of the imaging light so as to enable the imaging light to be in a first display time period t₁Is transmitted to the imaging module through the metal wire grid to enable the imaging light to be in a second display time period t₂The light beam is reflected by the metal wire grid and the reflector and then enters the imaging module.

19. The method according to claim 18, wherein the dimming module comprises a first polarization state adjusting unit, a second polarization state adjusting unit, a first metal wire grid and a second metal wire grid, the reflection module comprises a first reflection mirror and a second reflection mirror, the first metal wire grid and the second metal wire grid have parallel extending directions, the image light emitted from the image source module comprises a first polarization direction polarized light and a second polarization direction polarized light, and the polarization directions of the first polarization direction polarized light and the second polarization direction polarized light are perpendicular;

during the first display time period t₁The first polarization state adjusting unit loads a first voltage signal, and the second polarization state adjusting unit loads a second voltage signal;

in the second display time period t₂The first polarization state adjusting unit loads the second voltage signal, and the second polarization state adjusting unit loads the second voltage signalA voltage signal;

wherein, when the first polarization state adjusting unit or the second polarization state adjusting unit loads the first voltage signal, the light is directly transmitted, and when the first polarization state adjusting unit or the second polarization state adjusting unit loads the second voltage signal, the polarization direction of the light is rotated by 90 °.

20. The method according to claim 18, wherein the dimming module comprises a first polarization state adjusting unit, a second polarization state adjusting unit, a first metal wire grid and a second metal wire grid, the reflection module comprises a first reflection mirror and a second reflection mirror, the first metal wire grid and the second metal wire grid have vertical extending directions, the image light emitted from the image source module comprises a first polarization direction polarized light and a second polarization direction polarized light, and the first polarization direction polarized light and the second polarization direction polarized light have vertical polarization directions;

during the first display time period t₁The first polarization state adjusting unit loads a second voltage signal, and the second polarization state adjusting unit loads a first voltage signal;

in the second display time period t₂The first polarization state adjusting unit loads the first voltage signal, and the second polarization state adjusting unit loads the second voltage signal;

21. The method for driving the heads-up display system according to claim 18, wherein the image source module includes a display unit and a polarization state adjustment unit located at a light emitting side of the display unit, the dimming module includes a first metal wire grid and a second metal wire grid, extending directions of grid wires of the first metal wire grid and the second metal wire grid are parallel, the reflection module includes a first reflection mirror and a second reflection mirror, and linearly polarized light is emitted from the display unit;

when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The polarization state adjusting unit loads a second voltage signal and displays the second display time period t₂The polarization state adjusting unit loads a first voltage signal;

when the polarization direction of linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The polarization state adjusting unit loads the first voltage signal and displays the first voltage signal for the second display time period t₂The polarization state adjusting unit loads the second voltage signal;

the polarization state adjusting unit enables light to be directly transmitted when the first voltage signal is loaded, and enables the polarization direction of the light to be rotated by 90 degrees when the second voltage signal is loaded.

22. The method of driving the heads-up display system according to claim 21, wherein the dimming module further includes a first polarization state adjusting unit and a second polarization state adjusting unit, the first polarization state adjusting unit being located between the first metal wire grid and the second metal wire grid, the second polarization state adjusting unit being located on an optical path between the first metal wire grid and the first mirror or an optical path between the second metal wire grid and the second mirror;

when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The first polarization state adjusting unit loads the first voltage signal; in the second display time period t₂The second polarization state adjusting unit loads the first voltageA signal;

when the polarization direction of linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The first polarization state adjusting unit loads a second voltage signal; in the second display time period t₂And the second polarization state adjusting unit loads the second voltage signal.

23. The method for driving the head-up display system according to claim 18, wherein the image source module includes a display unit and a polarization state adjustment unit located at a light emitting side of the display unit, the dimming module includes a first polarization state adjustment unit, a second polarization state adjustment unit, a first metal wire grid and a second metal wire grid, the first metal wire grid and the second metal wire grid have vertical extending directions, the reflection module includes a first mirror and a second mirror, and the display unit emits linearly polarized light;

when the polarization direction of the linearly polarized light emitted by the display unit is parallel to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The polarization state adjusting unit and the first polarization state adjusting unit are loaded with a second voltage signal, and in the second display time period t₂The polarization state adjusting unit loads a first voltage signal, and the second polarization state adjusting unit loads a second voltage signal;

when the polarization direction of linearly polarized light emitted by the display unit is perpendicular to the extending direction of the grid lines of the first metal wire grid, in the first display time period t₁The polarization state adjusting unit loads a first voltage signal, the first polarization state adjusting unit loads a second voltage signal, and the second display time period t is₂The second voltage signal is loaded by the polarization state adjusting unit, and the second voltage signal is loaded by the second polarization state adjusting unit;

wherein the polarization state adjusting unit, the first polarization state adjusting unit, or the second polarization state adjusting unit directly transmits light when the first voltage signal is loaded, and the polarization direction of the light is rotated by 90 ° when the second voltage signal is loaded by the polarization state adjusting unit, the first polarization state adjusting unit, or the second polarization state adjusting unit.

24. A vehicle comprising the head-up display system of any one of claims 1 to 17.