CN115480403B

CN115480403B - Projection device and vehicle

Info

Publication number: CN115480403B
Application number: CN202211141573.7A
Authority: CN
Inventors: 陈波; 邹冰; 叶亚斌
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-03-18
Filing date: 2022-03-18
Publication date: 2024-03-15
Anticipated expiration: 2042-03-18
Also published as: WO2023173933A1; CN116804798A; CN115480403A

Abstract

The application provides a projection device and a vehicle. The projection device comprises an image providing unit, N wavelength selecting units and a reflecting unit, wherein the image providing unit projects light beams of N different image contents, the 1 st to N th wavelength selecting units in the N wavelength selecting units are sequentially arranged along the projection direction of the light beams of the N different image contents, the N wavelength selecting units are used for reflecting the N light beams, the different wavelength selecting units are used for reflecting light with different wavelengths, the i th wavelength selecting unit in the N wavelength selecting units is also used for transmitting incident light of the i+1th to N-th wavelength selecting units, the i value is 1 to N-1, and the reflecting unit is used for reflecting the received N light beams so as to form images corresponding to the different image contents.

Description

Projection device and vehicle

The present application is a divisional application, the filing number of the original application is 202210273410.8, the filing date of the original application is 2022, month 03 and 18, and the entire contents of the original application are incorporated herein by reference.

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a projection apparatus and a vehicle.

Background

The augmented reality Head Up Display (HUD) technology is a technology of projecting content displayed on a display to eyes of a user through a windshield by an optical system, and is widely used in vehicles including automobiles. When the augmented reality HUD technology is realized, in order to enable the display effect to be better, the stereoscopic virtual image is displayed through double focuses.

In the related art, a projection device is used for bifocal display of a stereoscopic virtual image, and the projection device includes a first display, a second display, a first mirror, a second mirror, and a third mirror. The image information of the first display is reflected to the eyes of the user through the first mirror, the second mirror and the third mirror, and the image information of the second display is reflected to the eyes of the user through the third mirror.

In the related art, the projection device adopts a three-lens space folding reflection scheme, and the volume of the projection device is relatively large because a plurality of reflectors in the projection device cannot be shielded.

Disclosure of Invention

The application provides a projection device and a vehicle, which can enable the volume of the projection device to be smaller.

In a first aspect, the present application provides a projection apparatus, including an image providing unit, N wavelength selecting units, and a reflecting unit, N being greater than 1; the image providing unit is used for projecting light beams of N logic areas, and different light beams correspond to different image contents; the 1 st to the nth wavelength selective units are sequentially arranged along the projection direction of the N light beams, the N wavelength selective units are used for reflecting the N light beams to the reflecting unit, different wavelength selective units are used for reflecting light with different wavelengths, the ith wavelength selective unit in the N wavelength selective units is also used for transmitting incident light or reflected light or incident light and reflected light of the i+1th to the nth wavelength selective units, and the i takes a value of 1 to N-1; the reflecting unit is used for reflecting the received N light beams to form images corresponding to different image contents.

In the solution shown in the present application, the N beams are beams of N logic areas in the image providing unit. Different ones of the N wavelength selective elements are configured to reflect light of different wavelengths, and an i-th one of the N wavelength selective elements is further configured to transmit incident light of the i+1th to N-th wavelength selective elements. In this way, the N wavelength selection units can have overlapping portions, the spatial light path is relatively compact, and the volume of the projection apparatus can be made relatively small.

In the above scheme, each wavelength selection unit reflects a corresponding light beam to the reflection unit, and different light beams load different image contents, so that multi-focal-plane display can be realized.

In one possible implementation, the incident light of the (j+1) th wavelength selective unit of the N wavelength selective units is transmitted from the 1 st to the j th wavelength selective units in sequence before being incident on the (j+1) th wavelength selective unit, and j has a value of 1 to N-1.

In this way, the incident light of the j+1th wavelength selective cell is transmitted from the 1 st to the j th wavelength selective cells, so that it is not necessary to specially design whether one end of the adjacent wavelength selective cell needs to be staggered or not, and implementation is easy.

In one possible implementation, the reflected light of the j+1th wavelength selective element of the N wavelength selective elements is sequentially transmitted from the j-th to the 1 st wavelength selective element before being incident on the reflecting element, and the j takes a value of 1 to N-1.

In this way, the reflected light of the j+1th wavelength selective element is transmitted from the 1 st to the j th wavelength selective element, so that it is not necessary to specially design whether one end of the adjacent wavelength selective element needs to be staggered or not, and implementation is easy.

In a possible implementation, the N light beams output by the image providing unit are different in wavelength, and different wavelength selecting units are used for reflecting different light beams.

In the scheme shown in the application, each wavelength selection unit is used for reflecting one light beam, the wavelengths of N light beams are different, and N images with different colors can be provided.

In one possible implementation, each of the N wavelength selective elements is one of a band filter, a holographic optical element (holographic optical element, HOE) bulk grating, or a diffractive optical element (diffractive optical element, DOE); alternatively, the nth wavelength selective element is a mirror, and the ith wavelength selective element is one of a band filter, an HOE bulk grating, or a DOE.

Thus, the N wavelength selection units have various designs, and the implementation difficulty is low.

In one possible implementation manner, the first surface of the kth wavelength selective unit of the N wavelength selective units is used for reflecting the light beam of the image content corresponding to the kth wavelength selective unit and transmitting the light beam of the image content corresponding to the kth+1th to nth wavelength selective unit, and the value of k is at least one value of 1 to N-1; a partial region of the second surface of the kth wavelength selective element is configured to reflect the reflected light of the kth +1 wavelength selective element.

In the solution shown in the present application, the second surface of the kth wavelength selective element is specially designed, and a partial area of the second surface is capable of reflecting the reflected light of the kth+1th wavelength selective element. Therefore, when the distance from the light beam of the image content corresponding to the kth+1th wavelength selection unit to the imaging position is constant, the reflected light can make a round trip between the kth wavelength selection unit and the kth+1th wavelength selection unit at least once, and the optical path requirement can be met when the distance between the kth wavelength selection unit and the kth+1th wavelength selection unit is smaller, and the volume of the projection device is smaller.

In one possible implementation, the wavelengths of the N light beams output by the image-providing unit are the same.

In the solution shown in the present application, the N wavelength selective units are respectively configured to reflect light in different wavelength ranges, where each wavelength range may include wavelengths of one or more wavelength bands, and a union of the different wavelength ranges corresponding to the N wavelength selective units is less than or equal to a wavelength range of the light beam. In this way, since the wavelengths of the N light beams are the same, the image providing unit is easy to implement.

In one possible implementation manner, the (m+1) th wavelength selecting unit of the N wavelength selecting units is configured to absorb light transmitted to the (m+1) th wavelength selecting unit in the light beam of the image content corresponding to the (m+1) th wavelength selecting unit, where the value of m is at least one value of 1 to N-1.

In the embodiment shown in the present application, the mth wavelength selective element can reflect only light in a certain wavelength range, and cannot reflect light of all wavelengths in the incident light, so that there is a portion of light transmitted to the mth+1th wavelength selective element, and there is light that the mth+1th wavelength selective element can reflect in the portion of light. The (m+1) th wavelength selective element absorbs this portion of the light, e.g. using an energy attenuation device, instead of reflecting to the reflective element, so that two images of the same image content are not formed.

In one possible implementation, each of the N wavelength selective units is a band filter; alternatively, the nth wavelength selective unit is a mirror, and the ith wavelength selective unit is a band filter.

Thus, the N wavelength selection units have various designs, and the implementation difficulty is low. When the wavelength selection unit is a wavelength band filter, the wavelength band filter may be a multi-channel filter, the finally displayed image is a color image, the wavelength band filter may be a single-channel filter, and the finally displayed image is a monochrome image.

In one possible implementation manner, the first surface of the kth wavelength selective unit in the N wavelength selective units is configured to reflect part of light in the light beam of the image content corresponding to the kth wavelength selective unit and transmit part of light in the light beam of the image content corresponding to the kth+1th to nth wavelength selective unit, where the value of k is at least one value from 1 to N-1; a partial region of the second surface of the kth wavelength selective element is configured to reflect the reflected light of the kth +1 wavelength selective element.

In one possible implementation, the 1 st to nth wavelength selection units are sequentially arranged in parallel along the projection direction of the N light beams. Therefore, the N wavelength selection units are parallel, so that the implementation difficulty is low, and the size of the projection device is smaller.

In one possible implementation manner, the first end of the j-th wavelength selection unit in the N wavelength selection units is staggered from the first end of the j+1th wavelength selection unit, and j takes a value of 1 to N-1; the incident light of the j+1th wavelength selective unit is not transmitted from the 1 st to the j th wavelength selective units before being incident on the j+1th wavelength selective unit, and the reflected light of the j+1th wavelength selective unit is transmitted from the j to the 1 st wavelength selective units in turn before being incident on the reflecting unit.

Thus, the incident light of the j+1th wavelength selective unit is not transmitted from the 1 st to the j th wavelength selective unit before being incident to the j+1th wavelength selective unit, so that the light beam corresponding to the j+1th wavelength selective unit only passes through the other wavelength selective units once, and the light loss is reduced.

In one possible implementation manner, the second end of the j-th wavelength selection unit in the N wavelength selection units is staggered from the second end of the j+1th wavelength selection unit, and j has a value of 1 to N-1; the incident light of the j+1th wavelength selective unit is transmitted from the 1 st to the j th wavelength selective units in turn before being incident on the j+1th wavelength selective unit, and the reflected light of the j+1th wavelength selective unit is not transmitted from the j to the 1 st wavelength selective units before being incident on the reflecting unit.

Thus, the reflected light of the j+1th wavelength selective unit is not transmitted from the j to the 1 st wavelength selective units before being incident on the reflecting unit, so that the light beam corresponding to the j+1th wavelength selective unit only passes through the other wavelength selective units once, and the light loss is reduced.

In a second aspect, the present application provides a projection apparatus including an image providing unit, a first wavelength selecting unit, a second wavelength selecting unit, and a reflecting unit; the image providing unit is used for projecting two light beams which respectively correspond to different image contents; the first wavelength selection unit and the second wavelength selection unit are arranged in a stacked manner along the projection direction of the two light beams; the first wavelength selection unit and the second wavelength selection unit are used for reflecting the two light beams, wherein the first wavelength selection unit and the second wavelength selection unit are used for reflecting light with different wavelengths, and the first wavelength selection unit is also used for transmitting incident light of the second wavelength selection unit; the reflecting unit is used for reflecting the received two light beams to form images corresponding to the different image contents.

In the solution shown in the application, different wavelength selective units of the two wavelength selective units are used for reflecting light with different wavelengths, and the first wavelength selective unit is also used for transmitting the incident light of the second wavelength selective unit. In this way, the two wavelength selection units can have overlapping portions, the spatial light path is compact, and the volume of the projection device can be made small.

In a third aspect, the present application provides a projection apparatus including an image providing unit, three wavelength selecting units, and a reflecting unit;

the image providing unit is used for projecting three light beams which respectively correspond to different image contents;

the 1 st to 3 rd wavelength selection units in the three wavelength selection units are sequentially stacked along the projection direction of the three light beams;

the three wavelength selection units are used for reflecting the three light beams, wherein different wavelength selection units are used for reflecting light with different wavelengths, and the 1 st wavelength selection unit is used for transmitting incident light of the 2 nd wavelength selection unit and the 3 rd wavelength selection unit; the 2 nd wavelength selection unit is used for transmitting the incident light of the 3 rd wavelength selection unit;

the reflecting unit is used for reflecting the received three light beams to form images corresponding to the different image contents.

In a fourth aspect, the present application provides a vehicle comprising a windscreen and a projection device as described in the first aspect and in a possible implementation of the first aspect, or a projection device as described in the second aspect, or a projection device as described in the third aspect;

the projection device is used for outputting N light beams to the windshield glass so as to form images corresponding to different image contents.

Drawings

FIG. 1 is a schematic view of a conventional projection apparatus;

FIG. 2 is a schematic diagram of a projection device according to an exemplary embodiment of the present application;

FIG. 3 is a schematic view of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 4 is a schematic view of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 5 is a schematic illustration of a plurality of HOEs provided in accordance with an exemplary embodiment of the present application;

FIG. 6 is a schematic diagram of a projection device according to an exemplary embodiment of the present application;

FIG. 7 is a schematic view of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 8 is an enlarged view of a wavelength selective cell provided in an exemplary embodiment of the present application;

FIG. 9 is a schematic diagram of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 10 is a schematic diagram of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 11 is a schematic view of a projection apparatus according to an exemplary embodiment of the present application;

FIG. 12 is a schematic view of a projection device and windshield provided in accordance with an exemplary embodiment of the present application;

fig. 13 is a functional framework schematic of a vehicle provided in an exemplary embodiment of the present application.

Description of the drawings

1. An image providing unit; 2. n wavelength selection units; 3. a reflection unit;

01. a first wavelength selection unit; 02. a second wavelength selection unit;

12. a sensor system; 14. a control system; 16. a peripheral device; 18. a power supply; 20. a computer system;

2001. a processor; 2002. a memory; 32 heads-up display system.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Some term concepts related to the embodiments of the present application are explained below.

1. HUD is a system that propagates image content into the eyes of a user through an optical system. For example, HUDs are used in vehicles, and information such as the running speed of a vehicle, road conditions, etc., displayed on a display is transmitted to the eyes of a driver through an optical system. Therefore, under dark, rainy and snowy weather and complex road conditions, the driver can see related information without low head, and the method is very beneficial to safe driving of the driver. For another example, in recent years, an augmented reality HUD is developed, which is applied to a vehicle, and a digital image is superimposed on an off-vehicle real environment through an optical system, so that a driver obtains a visual effect of augmented reality, and the augmented reality HUD can be used in scenes such as augmented reality navigation, adaptive cruising, lane departure warning and the like.

2. The dual-focus head-up display system is a HUD system for forming two projection surfaces based on two different projection distances.

The conventional projection apparatus is described below.

Fig. 1 provides a schematic structural diagram of a conventional projection device, which is a device for displaying virtual images in a bifocal manner. Referring to fig. 1, the projection apparatus includes a first display, a second display, a first mirror, a second mirror, and a third mirror. The image information of the first display is projected to the eyes of the user through the first mirror, the second mirror and the third mirror, and the image information of the second display is projected to the eyes of the user through the third mirror. Therefore, the projection device adopts a three-lens space folding reflection scheme, and the volume of the projection device is relatively large because a plurality of reflectors in the projection device cannot be shielded. And when showing three or more than three stereoscopic virtual images, still adopt many lens folding reflection schemes, can use more speculums, and then can make projection arrangement's volume bigger.

Embodiments of the present application provide a projection apparatus in which a plurality of mirrors are not used to reflect a light beam, but a wavelength selective unit is used to reflect the light beam. The wavelength selection unit can have an overlapping portion, and the spatial light path is relatively compact, so that the volume of the projection device is relatively small.

The projection device provided by the embodiment of the application can be applied to video entertainment and auxiliary driving scenes. The projection device may be used alone or as a component in other devices, for example, in vehicles, in head-mounted display devices, or in optical desktop display devices.

Fig. 2 is a schematic structural diagram of a projection apparatus according to an embodiment of the present application. As shown in fig. 2, the projection apparatus includes an image providing unit 1, N wavelength selecting units 2, and a reflecting unit 3. The image providing unit 1 is configured to project N light beams, different light beams corresponding to different image contents. The N wavelength selection units 2 include 1 st to N th wavelength selection units, and the 1 st to N th wavelength selection units are sequentially arranged along the projection direction of the N light beams. The N wavelength selective units 2 are used for reflecting the N light beams to the reflecting unit 3, different wavelength selective units are used for reflecting light with different wavelengths, and the ith wavelength selective unit in the N wavelength selective units 2 is also used for transmitting incident light from the (i+1) th to the nth wavelength selective units, wherein the value of i is 1 to N-1. The reflecting unit 3 is used for reflecting the received N light beams to form images corresponding to different image contents. The positions of the images corresponding to the different image contents are different.

Wherein the incident light of the i-th wavelength selective element refers to the light incident to the i-th wavelength selective element. The 1 st to nth wavelength selective units are arranged in a stacked order along the projection direction of the N light beams, and each wavelength selective unit is responsible for reflecting light carrying one image content. The N light beams supplied from the image supply unit 1 have the same wavelength or are different from each other. In fig. 2, the arrowed line indicates the transmission direction of the light beam.

In the projection apparatus shown in fig. 2, for example, the incident light of the (j+1) -th wavelength selective unit is sequentially transmitted from the (1) -th to (j) -th wavelength selective units before being incident on the (j+1) -th wavelength selective unit, and j has a value of 1 to N-1. Wherein the incident light of the j+1th wavelength selective element refers to the light incident to the j+1th wavelength selective element.

And the reflected light of the j+1th wavelength selective element, which is reflected by the j+1th wavelength selective element in the light beam carrying the first image content, is transmitted from the j-th to 1-th wavelength selective elements in order before being incident on the reflection element 3.

For example, in the projection apparatus shown in fig. 2, the image supply unit 1 supplies N light beams, the wavelengths of which are different. The 1 st light beam is incident on the 1 st wavelength selection unit, the 1 st light beam is reflected to the reflection unit 3 by the 1 st wavelength selection unit, and the 1 st light beam is reflected by the reflection unit 3 to form an image. The 2 nd light beam is transmitted through the 1 st wavelength selection unit and is incident to the 2 nd wavelength selection unit, the 2 nd light beam is reflected by the 2 nd wavelength selection unit, the 2 nd light beam is transmitted to the reflection unit 3 through the 1 st wavelength selection unit, and the 2 nd light beam is reflected by the reflection unit 3 to form an image. And so on, each of the N beams will be reflected to form an image.

Fig. 3 is a schematic structural diagram of another projection apparatus according to an embodiment of the present application. The difference from the projection device shown in fig. 2 is that: the first end of the j-th wavelength selection unit is staggered with the first end of the j+1th wavelength selection unit, and j takes a value of 1 to N-1.

As shown in fig. 3, the first end is the end from which light exits the j+1th wavelength selective element, and the incident light of the j+1th wavelength selective element is transmitted from the 1 st to the j th wavelength selective element in order before being incident on the j+1th wavelength selective element. And the reflected light of the j+1th wavelength selective element is not transmitted from the j-th to 1-th wavelength selective elements before being incident on the reflecting element 3, i.e., is directly reflected from the j+1th wavelength selective element to the reflecting element 3.

For example, in the projection apparatus shown in fig. 3, the image supply unit 2 supplies N light beams, the wavelengths of which are different. The 1 st light beam is incident on the 1 st wavelength selection unit, the 1 st wavelength selection unit reflects the 1 st light beam to the reflection unit 3, and the reflection unit 3 reflects the 1 st light beam to form the image 1. The 2 nd light beam is transmitted to the 2 nd wavelength selective unit through the 1 st wavelength selective unit, and the 2 nd wavelength selective unit directly reflects the 2 nd light beam to the reflection unit 3. The reflection unit 3 reflects the 2 nd light beam to form an image 2. And so on, each of the N beams will be reflected to form an image.

Fig. 4 is a schematic structural diagram of another projection apparatus according to an embodiment of the present application. The difference from the projection device shown in fig. 2 is that: the second end of the j-th wavelength selection unit is staggered with the second end of the j+1th wavelength selection unit, and j takes a value of 1 to N-1.

As shown in fig. 4, the second end is an end at which light is incident from the j+1th wavelength selective unit, and the incident light of the j+1th wavelength selective unit is not transmitted from the 1 st to the j-th wavelength selective units before being incident to the j+1th wavelength selective unit, i.e., is directly incident from the image providing unit 1 to the j+1th wavelength selective unit. And the reflected light of the j+1th wavelength selective element is sequentially transmitted from the j-th to the 1 st wavelength selective element before being incident on the reflection element 3.

For example, in the projection apparatus shown in fig. 4, the image supply unit 2 supplies N light beams, the wavelengths of which are different. The 1 st light beam is incident on the 1 st wavelength selection unit, the 1 st wavelength selection unit reflects the 1 st light beam to the reflection unit 3, and the reflection unit 3 reflects the 1 st light beam to form the image 1. The 2 nd light beam does not pass through the 1 st wavelength selection unit, but directly enters the 2 nd wavelength selection unit, the 2 nd light beam is reflected by the 2 nd wavelength selection unit, the 2 nd light beam passes through the 1 st wavelength selection unit and is transmitted to the reflection unit 3, the reflection unit 3 reflects the 2 nd light beam, and the image 2 is formed. And so on, each of the N beams will be reflected to form an image.

In this way, with the projection apparatus shown in fig. 3 and 4, the incident light of the (j+1) th wavelength selection unit only needs to pass through the (1) th to (j) th wavelength selection units once, and compared with the scenes of passing through the (1) st to (j) th wavelength selection units twice, the light loss can be reduced, and the display efficiency can be improved.

The specific structures of the respective portions in the projection apparatus are described below with respect to the projection apparatus shown in fig. 2 to 4 described above, respectively.

The image providing unit 1 includes N logical areas that provide different image contents, respectively, by way of example. For example, N has a value of 2, and the image content provided in one logical area is information such as vehicle speed, and the image content provided in the other logical area is navigation information.

Alternatively, the N logical areas may or may not belong to one display. For example, N has a value of 2, one logical area belongs to the first display, and the other logical area belongs to the second display.

Alternatively, the N logic regions may be located in the same plane or may be located in different planes.

By way of example, the image-rendering unit 1 may be any one of a liquid crystal on silicon (liquid crystal on silicon, LCOS) display, a liquid crystal display (liquid crystal display, LCD) display, a digital light processing (digital light procession, DLP) display, or a microelectromechanical system (micro-electro-mechanical system, MEMS) display. Among other things, LCD displays may include thin film transistor (thin film transistor, TFT) displays and the like. The light source of the various displays may be a light-emitting diode (LED) light source or a Laser Diode (LD) light source. The display may also be referred to as an image source or an image generation unit.

Illustratively, the wavelengths of the N light beams provided by the image-providing unit 1 are different, and the wavelengths of the light emitted by the light sources of the N logic areas are different. Different wavelength selective elements reflect light beams of different wavelengths. The wavelengths of the N light beams can be set arbitrarily according to actual needs, for example, the N value is 3, the light beams of the three image contents are all monochromatic light, and the 3 light beams are respectively red light beams, green light beams and blue light beams.

Alternatively, the wavelengths of the N light beams supplied from the image supply unit 1 are the same, and then different wavelength selective units reflect light of different wavelength ranges in the light beams. The wavelength range of the light beam can be set arbitrarily according to actual needs. For example, if the wavelength range of the light beam is set to be the wavelength range of white light, the light source is a white light source, or is a three-primary-color light source, and red, green and blue light emitted from the three-primary-color light source forms white light.

Alternatively, the projection directions of the N light beams may be parallel, or may have a certain included angle.

Alternatively, the projection directions of the N light beams may or may not be in the same plane.

The N wavelength selective units 2 may or may not be equal in size, for example. The N wavelength selective units 2 may have a planar structure or a curved structure.

Illustratively, the placement of the N wavelength selective elements 2 may be determined based on the location of the formed image. The N wavelength selection units 2 may be placed in parallel or at a certain angle.

When the N wavelength selection units 2 are placed in parallel, the 1 st to N th wavelength selection units are sequentially arranged in parallel along the projection direction of the N light beams, or the N wavelength selection units 2 are sequentially arranged in parallel and overlapped, and the intervals of the N wavelength selection units 2 may be the same or different. In this way, the N wavelength selection units 2 are arranged in parallel in a stacked manner, which can save space and further reduce the size of the projection apparatus.

Alternatively, in the case where the wavelengths of the N light beams are not identical, each wavelength selection unit may be one of a band filter, an HOE bulk grating, or a DOE. Alternatively, the nth wavelength selective element is a mirror, and the ith wavelength selective element is one of a band filter, an HOE bulk grating, or a DOE. The reason why the nth wavelength selective element may be a mirror is that: the nth wavelength selective unit is not followed by other wavelength selective units, other light does not pass through the nth wavelength selective unit, and only one light beam is incident on the nth wavelength selective unit, so that the light beam is reflected only, and other light beams do not need to be transmitted.

Each wave band filter plate can be manufactured through coating processing, and wavelength separation is achieved through coating, so that the space structure is more compact. Each wave band filter can be a single-channel filter or a multi-channel filter. For example, each wavelength selection unit adopts a band filter, and assuming that the N value is 3, the 3 wavelength selection units include a first band filter, a second band filter, and a third band filter, and the first band filter, the second band filter, and the third band filter are sequentially arranged along the projection directions of the N light beams. Taking a single-channel filter as an example, the first wave band filter uses a 490nm cut-off high-pass wave band filter, so that the first wave band filter reflects 380-475nm light and transmits 505-800nm light. The second wave band filter uses 650nm cut-off high-pass wave band filter, the second wave band filter reflects 505nm-633nm light, and the second wave band filter transmits more than 685nm light. The third band filter uses a high-pass band filter with a cut-off of 760nm or more.

To increase the light efficiency, the 1 st beam may have a center wavelength of 430nm and a bandwidth of less than 40nm. The center wavelength of the 2 nd beam may be 550nm with a bandwidth of less than 30nm. The 3 rd beam may have a center wavelength of 710nm and a bandwidth of less than 30nm. In this way, the light source in the display may be an LED light source or an LD light source.

HOE has wavelength selectivity and angle selectivity. The principle of HOE is as follows:

the wavelength of light that the HOE can reflect can be set according to the diffraction formula (1).

sinθ _m ＝λ/(2nΛ) (1)

In formula (1), θ _m Where Λ is the grating spacing of the HOE and n is the average refractive index of the HOE. For different HOEs, light of wavelengths that satisfy formula (1) is reflected by the HOE and light of wavelengths that do not satisfy formula (1) is transmitted by the HOE. Thus, wavelength separation can be achieved by providing different HOEs for different wavelengths of light. The exit direction of diffracted light from the HOE can be determined by equation (2). Here, the HOE is a reflective grating, and the diffracted light may be considered as reflected light.

In the formula (2), the amino acid sequence of the formula (2),for the grating vector direction of the HOE, +.>For the vector direction of the incident light, +.>Is the vector direction of the diffracted light exit.

For example, N has a value of 3, and the 3 wavelength selective elements are HOE1, HOE2, and HOE3, respectively. By HOE1, HOE2, and HOE3 having different grating vector directions, incident light at the same incident angle can be emitted in different emission directions. Thus, light of different wavelengths can be separated by HOE with different grating vectors and different grating spacings. Fig. 5 is a schematic diagram of HOE1, HOE2, and HOE3, with three beams passing through HOE1, HOE2, and HOE3 for separation in fig. 5.

In addition, the DOE is similar to the HOE in principle and will not be described here again.

Alternatively, in order to reduce the volume of the wavelength selection unit 2, the HOE may be a thin film HOE.

Alternatively, the HOEs and DOEs may be prepared by exposure, electron beam lithography, nanoimprinting, or other optical precision component processing.

Alternatively, in the case where the wavelengths of the N light beams are the same, each wavelength selection unit may be a band filter. Alternatively, the ith wavelength selective element is a band filter, and the nth wavelength selective element is a mirror. The reason why the nth wavelength selective element may be a mirror is that: the nth wavelength selection unit is not provided with other wavelength selection units, other light can not pass through (permeate) the nth wavelength selection unit, the nth wavelength selection unit can reflect the received light, and other light beams do not need to be transmitted. Here, each wavelength selection unit is configured to reflect light in a different wavelength range, each wavelength range may include wavelengths of one or more wavelength bands, where the wavelength range includes wavelengths of a plurality of wavelength bands, the wavelength band filter may employ a multi-channel filter, the finally displayed image is a color image, and where the wavelength range includes wavelengths of one wavelength band, the wavelength band filter may employ a single-channel filter, and the finally displayed image is a monochrome image.

For example, each wavelength selection unit adopts a band filter, assuming that the N has a value of 3, and the 3 wavelength selection units include a first band filter, a second band filter, and a third band filter, which are sequentially arranged along the projection directions of the 3 light beams. The 3 wavelength selection units are respectively used for reflecting light in a first wavelength range, light in a second wavelength range and light in a third wavelength range, each wavelength range can comprise a plurality of discontinuous wavelength bands or each wavelength range can comprise a wavelength of one wavelength band, and the three wavelength ranges are not overlapped. Alternatively, the union of the three wavelength ranges is smaller than or equal to the wavelength range of the light beam supplied from the image supply unit 1. The first light beam is incident on the first band filter, and light in a first wavelength range in the first light beam is reflected by the first band filter and is incident on the reflection unit 3. The second light beam is incident on the second band filter, and light in the second wavelength range in the second light beam is reflected by the second band filter and is incident on the reflection unit 3. The third light beam is incident on the third band filter, and light in a third wavelength range in the third light beam is reflected by the third band filter and is incident on the reflection unit 3.

Alternatively, the above-described band filter may employ a dichroic filter, which may also be referred to as a dichroic mirror.

In addition, different types of wavelength selective units may exist in the N wavelength selective units 2, for example, the 1 st wavelength selective unit is a band filter, and the 2 nd wavelength selective unit is an HOE or a DOE.

For example, in the case where the wavelengths of the N light beams are the same, the mth wavelength selection unit is present in the N wavelength selection units 2, where m has a value of 1 to N-1, and the mth wavelength selection unit can reflect light in a certain wavelength range and cannot reflect light of all wavelengths in the incident light, so that there is a portion of the light transmitted to the m+1th wavelength selection unit, and there is light that the m+1th wavelength selection unit can reflect. If the part of light belongs to the light beam of the image content corresponding to the mth wavelength selective unit, the part of light also contains the image content and can be understood as stray light. If the part of the light is incident on the reflecting unit 3, two images of the same image content appear, so the part of the light does not need to be reflected to the reflecting unit 3. For example, the 1 st wavelength selective element corresponds to a first image content, which corresponds to a first light beam. The 1 st wavelength selective element reflects light of a first wavelength range in the first light beam, and light other than the first wavelength range in the first light beam is transmitted to the 2 nd wavelength selective element.

In order to prevent the portion of light from being reflected to the reflection unit 3, the incident position of the portion of light in the (m+1) th wavelength selective unit may absorb the portion of light, for example, N has a value of 2, the 1 st wavelength selective unit corresponds to the light beam of the first image content, the 2 nd wavelength selective unit corresponds to the light beam of the second image content, and each light beam has a wavelength range of 500 to 600nm. The 1 st wavelength selective unit reflects 500-540 nm light, the 2 nd wavelength selective unit reflects 560-600 nm light, 541-600 nm light in the first image content beam is transmitted from the 1 st wavelength selective unit to the 2 nd wavelength selective unit, and the 2 nd wavelength selective unit needs to absorb 541-600 nm light in the first image content beam.

Alternatively, the m+1th wavelength selective element may absorb the portion of light in such a manner that: an absorption film is coated at the incidence position of the part of light, and the absorption film is used for absorbing the part of light. Alternatively, by plating a reflective film on the incidence area of the part of light on the back surface of the mth wavelength selective unit (the surface close to the (m+1) th wavelength selective unit), the part of light is reflected to other positions without entering the reflecting unit 3. Alternatively, by setting the distance and/or angle between adjacent wavelength selective elements such that part of the light is reflected to other positions, not entering the reflection unit 3.

For example, in the case where the wavelengths of the N light beams are the same, the projection apparatus described in fig. 4 may be employed such that the incident light of the (j+1) th wavelength selection unit does not pass through the (1) th to (j) th wavelength selection units, and the (1) th to (j) th wavelength selection units do not reflect the incident light, and the same image content does not correspond to multiple virtual images.

If the incident light of the (j+1) th wavelength selection unit passes through the (1) th to (j) th wavelength selection units (see the projection apparatus shown in fig. 2 or 3), the (1) th to (j) th wavelength selection units also reflect part of the light beam of the image content corresponding to the (j+1) th wavelength selection unit, and the part of the light beam can be understood as stray light, and if the part of the light is incident on the reflection unit 3, the same image content corresponds to a plurality of images. For example, N has a value of 2, the 1 st wavelength selection unit corresponds to the light beam of the first image content, the 2 nd wavelength selection unit corresponds to the light beam of the second image content, and each light beam has a wavelength range of 500 to 600nm. The 1 st wavelength selective unit reflects 500-540 nm light, the 2 nd wavelength selective unit reflects 560-600 nm light, the 500-540 nm light in the light beam of the second image content is reflected by the 1 st wavelength selective unit, and if the 500-540 nm light in the light beam of the second image content is incident to the reflecting unit 3, the second image content corresponds to two images.

In order to prevent the same image content from corresponding to a plurality of images, the image providing unit 1, the N wavelength selection units 2, and the reflection unit 3 may be designed to cooperate with each other so that the part of light is not incident to the reflection unit 3 after being reflected by the 1 st to j th wavelength selection units. For example, the positions and the projection directions of the N light fluxes supplied from the image supply unit 1, the pitches and angles between the N wavelength selection units 2, the angles and the apertures of the reflection units 3, and the like may be designed to prevent the same image content from corresponding to a plurality of images.

Fig. 6 exemplarily provides a structure of a projection apparatus, which can prevent a plurality of images from being corresponding to the same image content using the projection apparatus shown in fig. 6. Referring to fig. 6, the 3 light beams provided by the image-providing unit 1 are not parallel, and the 3 wavelength-selecting units are also not parallel. The 1 st wavelength selective unit reflects light of a first wavelength range in the light beam, the 2 nd wavelength selective unit 2 reflects light of a second wavelength range in the light beam, the 3 rd wavelength selective unit reflects light of a third wavelength range in the light beam, the first wavelength range, the second wavelength range, and the third wavelength range do not overlap, and the wavelength ranges of each light beam provided by the image providing unit 1 are integrated. The 1 st light beam in the first wavelength range is reflected by the 1 st wavelength selective element and enters the reflection element 3. The 2 nd light beam is incident on the 1 st wavelength selective element, the light of the first wavelength range is reflected by the 1 st wavelength selective element, and is not incident on the reflecting element 3 (the light transmission direction is indicated by a dotted line), and the light of the second wavelength range and the light of the third wavelength range are incident on the 2 nd wavelength selective element. The light in the second wavelength range in the 2 nd light beam is reflected by the 2 nd wavelength selective element and is incident on the reflecting element 3. The 3 rd light beam is incident on the 1 st wavelength selective element, the light of the first wavelength range is reflected by the 1 st wavelength selective element, and is not incident on the reflecting element 3 (the light transmission direction is indicated by a dotted line), and the light of the second wavelength range and the light of the third wavelength range are incident on the 2 nd wavelength selective element. The light in the second wavelength range in the 3 rd light beam is reflected by the 2 nd wavelength selective element and is not incident on the reflecting element 3 (the light transmission direction is indicated by a broken line). The light in the third wavelength range in the 3 rd light beam is incident on the 3 rd wavelength selective unit, reflected by the 3 rd wavelength selective unit, and incident on the reflection unit 3. In this way, each image content corresponds to one image, and no interference is generated between each image content and each image.

Illustratively, the reflecting unit 3 may be a curved mirror (e.g., a concave mirror), and the reflecting unit 3 may reduce aberration by using the curved mirror, so that the imaging effect is better. Here, only an example, any reflection unit 3 capable of reducing aberration may be applied to the embodiment of the present application.

Fig. 7 is a schematic structural diagram of another projection apparatus according to an embodiment of the present application. As shown in fig. 7, the kth wavelength selective element exists in the N wavelength selective elements 2, the kth wavelength selective element exists in a first surface and a second surface, the first surface is opposite to the second surface, the first surface is adjacent to the kth-1 wavelength selective element, and the second surface is adjacent to the kth+1th wavelength selective element.

Under the condition that the wavelengths of the N light beams are different, the first surface is used for reflecting the light beam of the image content corresponding to the kth wavelength selection unit and transmitting other incident light beams to the kth+1th wavelength selection unit, and the transmitted other light beams are the light beams of the image content corresponding to the kth+1th to Nth wavelength selection units. For example, N has a value of 2, the 1 st wavelength selective element corresponds to the first image content, the 2 nd wavelength selective element corresponds to the second image content, and the first surface of the 1 st wavelength selective element reflects the light beam of the first image content and transmits the light beam of the second image content. The partial region of the second surface of the kth wavelength selective element is used for reflecting the reflected light of the kth+1 wavelength selective element, i.e. such that the reflected light of the kth+1 wavelength selective element is reflected at least once by the kth wavelength selective element.

Under the condition that the wavelengths of the N light beams are the same, the first surface is used for reflecting part of light beams of the image content corresponding to the kth wavelength selection unit and transmitting other light to the kth+1th wavelength selection unit, and the transmitted other light is part of light beams of the image content corresponding to the kth+1th to Nth wavelength selection units. For example, N has a value of 2, the 1 st wavelength selective element corresponds to the first image content, the 2 nd wavelength selective element corresponds to the second image content, the first surface of the 1 st wavelength selective element reflects light in a first wavelength range of the light beam of the first image content, transmits light in a second wavelength range of the light beam of the second image content, and a union of the first wavelength range and the second wavelength range is a wavelength range of the light beam of the image content. The partial region of the second surface of the kth wavelength selective element is used for reflecting the reflected light of the kth+1 wavelength selective element, i.e. such that the reflected light of the kth+1 wavelength selective element is reflected at least once by the kth wavelength selective element.

In this way, in order to make the image corresponding to the image content clear, the distance (i.e., the optical path length) between the light of the image content from the emission to the imaging position is constant, and in the case where the optical path length is constant, the reflected light of the (k+1) -th wavelength selection unit is reflected by the partial region of the second surface, so that the optical path length of the light of the image content between the (k) th and (k+1) -th wavelength selection units becomes longer, and the distance between the (k) th and (k+1) -th wavelength selection units can be shortened. Also in the projection apparatus shown in fig. 7, in some cases, the distance between the kth and the kth+1th wavelength selective units is made longer, and the distance between the kth and the kth+1th wavelength selective units can be reduced, for example, the first position is above the second position, where the reflected light of the kth+1th wavelength selective unit is first incident on the kth wavelength selective unit, and the second position is the exit position of the reflected light of the kth wavelength selective unit. Therefore, the volume of the N wavelength selection units 2 can be reduced.

Wherein k takes on at least one value from 1 to N-1, that is: among the N wavelength selective units 2 there are one or more wavelength selective units, a partial region of the second surface of which has a reflection function, in particular a function of reflecting the reflected light of the adjacent wavelength selective unit. In the embodiment of the application, in 1 to N-1, the value of k is not limited, and the number of the values of k is not limited. In addition, the number of reflections of the reflected light of the (k+1) th wavelength selective element by the partial region of the second surface is not limited, and may depend on the size of the area of the reflection region of the second surface, and the larger the area, the larger the number of reflections may be.

Optionally, a partial region of the second surface of the kth wavelength selective unit is plated with a reflective film for reflecting the reflected light of the kth+1th wavelength selective unit. In fig. 7 it is shown that the second surface of the first wavelength selective element is provided with a reflective film.

In order to better understand that a partial region of the second surface is plated with a reflective film, an enlarged partial view of the wavelength selective unit is provided in fig. 8, and in fig. 8, the 1 st to N-1 st partial regions of the second surface of the wavelength selective unit are each plated with a reflective film.

The position of the partial area of the second surface of the kth wavelength selective unit may be set according to actual needs, the partial area may not be located on the target incident path of the kth+1th to nth wavelength selective units, and the reflected light of the kth+1th wavelength selective unit may be incident on the reflection unit 3. The target incidence path includes incidence paths of target light to the kth+1th to nth wavelength selective units, the target light being incidence light of the kth+1th to nth wavelength selective units.

Fig. 9 is a schematic structural diagram of another projection apparatus according to an embodiment of the present application. As shown in fig. 9, N has a value of 2, and the projection apparatus includes an image providing unit 1, a first wavelength selecting unit 01, a second wavelength selecting unit 02, and a reflecting unit 3.

The image-providing unit 1 is arranged to project two light beams corresponding to different image contents, i.e. the image-providing unit 1 has two logical areas, the image contents of which are different.

The first wavelength selection unit 01 and the second wavelength selection unit 02 are arranged in a stacked manner along the projection direction of the two light beams. The first wavelength selective unit 01 and the second wavelength selective unit 02 are used for reflecting the two light beams, the first wavelength selective unit 01 and the second wavelength selective unit 02 are used for reflecting light beams with different wavelengths, and the first wavelength selective unit 01 is also used for transmitting incident light of the second wavelength selective unit 02. The reflecting unit 3 is configured to reflect the received two light beams to form images corresponding to different image contents.

The two light beams include a first light beam and a second light beam, and in the case where the wavelengths of the first light beam and the second light beam are different, the first light beam is incident on the first wavelength selection unit 01, and the first wavelength selection unit 01 reflects the first light beam to the reflection unit 3. The second light beam is incident on the first wavelength selective unit 01, and the first wavelength selective unit 01 transmits the second light beam to the second wavelength selective unit 02. The second wavelength selective unit 02 reflects the second light beam, and the reflected second light beam is incident (transmitted) to the reflecting unit 3 through the first wavelength selective unit 01. The reflection unit 3 reflects the first light beam and the second light beam to form images corresponding to different image contents.

In the case where the wavelengths of the first light beam and the second light beam are the same, the first wavelength selection unit 01 reflects light of a first wavelength range, the second wavelength selection unit 02 reflects light of a second wavelength range, and the union of the first wavelength range and the second wavelength range becomes the wavelength range of the first light beam (or the wavelength range of the light beam output by the image providing unit 1). The first light beam is incident on the first wavelength selective unit 01, and the first wavelength selective unit 01 reflects light of a first wavelength range in the first light beam to the reflection unit 3. The second light beam is incident on the first wavelength selection unit 01, the first wavelength selection unit 01 transmits light of a second wavelength range in the second light beam to the second wavelength selection unit 02, and light of the first wavelength range is not reflected to the reflection unit 3, the second wavelength selection unit 02 reflects the light of the second wavelength range, and the light of the second wavelength range is incident (transmitted) to the reflection unit 3 through the first wavelength selection unit 01.

Here, the second light beam is described as an example in which the second light beam passes through the first wavelength selection means 01 twice, but the second light beam may pass through the first wavelength selection means 01 only when entering, or may pass through the first wavelength selection means 01 only when exiting. For a detailed description, see the description for fig. 3 and 4.

Fig. 10 is a schematic structural diagram of another projection device according to an embodiment of the present application. The first surface of the first wavelength selective unit 01 is for transmitting light (incident light) incident to the second wavelength selective unit 02, and a partial region of the second surface of the first wavelength selective unit 01 is for reflecting the reflected light of the second wavelength selective unit 02, the first surface being an opposite surface to the second surface, the partial region being such that the reflected light is reflected at least once at the first wavelength selective unit 01. In this way, in order to make clear the image corresponding to the image content, the distance (i.e., the optical path length) between the light emitted from the image content to the imaging position is constant, and in the case where the optical path length is constant, the reflected light of the second wavelength selection unit 02 is reflected by the partial region of the second surface of the first wavelength selection unit 01, so that the optical path length of the reflected light between the two wavelength selection units becomes longer, and the distance between the two wavelength selection units can be shortened.

The first wavelength selection unit 01 may be one of a band filter, an HOE, or a DOE, and the second wavelength selection unit 02 may be one of a band filter, an HOE, or a DOE, for example. Alternatively, the first wavelength selection unit 01 may be one of a band filter, HOE, or DOE, or the second wavelength selection unit 02 may be a mirror.

It should be noted that, only the structure of the projection device when N is 2 will be described briefly, and the specific description of the projection device is referred to in the foregoing description.

Fig. 11 is a schematic structural diagram of another projection apparatus according to an embodiment of the present application. As shown in fig. 11, N takes a value of 3, and the projection apparatus includes an image providing unit 1, three wavelength selecting units, and a reflecting unit 3.

The image-providing unit 1 is arranged to project three light beams corresponding to different image contents of the image-providing unit 1, i.e. the image-providing unit 1 has three logical areas, the image contents of which are different.

The 1 st to 3 rd wavelength selection units among the three wavelength selection units are arranged in a stacked manner along the projection direction of the three light beams. The three wavelength selective units are used for reflecting the three light beams, and different wavelength selective units are used for reflecting light with different wavelengths. Wherein the 1 st wavelength selective element is further configured to transmit the incident light of the 2 nd to 3 rd wavelength selective elements, and the 2 nd wavelength selective element is further configured to transmit the incident light of the 3 rd wavelength selective element.

The reflecting unit 3 is used for reflecting the received 3 light beams to form images corresponding to different image contents.

It should be noted that, only the structure of the projection device when N is 3 will be described briefly, and the specific description of the projection device is referred to in the foregoing description.

The embodiment of the application also provides a vehicle, which comprises a windshield glass and any one of the projection devices, wherein the windshield glass is used for reflecting N light beams from the projection devices to form N images corresponding to the N light beams. The N images and the driver are located on both sides of the windscreen, the N images being virtual images. The windshield may also be referred to as a windshield. Fig. 12 shows a schematic view of a projection device and a windscreen, wherein the projection device of fig. 12 comprises three wavelength selective elements forming three virtual images, virtual image 1, virtual image 2 and virtual image 3, respectively, and the vehicle comprises further parts, not shown in fig. 12.

By way of example, the vehicle may be a car, truck, motorcycle, bus, boat, airplane, helicopter, mower, recreational vehicle, casino vehicle, construction equipment, electric car, golf cart, train, trolley, etc., and embodiments of the present application are not particularly limited.

The N images are exemplary augmented reality display images, and the augmented reality display images are used for displaying information such as map auxiliary information and indication information of external objects. The indication information of the external object includes, but is not limited to, safe car distance, surrounding obstacle, reversing image and the like. The map assistance information is used as assistance driving, and includes, for example, but not limited to, a directional arrow, a distance, a travel time, and the like.

Alternatively, each of the N images is a status display image for displaying status information, entertainment information, and the like of the vehicle. Taking an automobile as an example, the state information of the vehicle is generally information displayed on a vehicle meter, which is also referred to as meter information, including, but not limited to, information of a traveling speed, a traveling mileage, a fuel amount, a water temperature, a lamp state, and the like.

Alternatively, the N images include an augmented reality display image and a status display image. For example, N has a value of 2, and one image is an augmented reality display image and the other image is a status display image.

Alternatively, the imaging distance of the augmented reality display image may be greater than the imaging distance of the status display image.

In addition, in the embodiment of the present application, N images may also be displayed on the projection screen.

For example, in a vehicle, the projection device may be provided with a housing for dust protection or the like, which housing may also be referred to as a dust cover.

In this embodiment of the application, projection arrangement adopts a plurality of wavelength selection units, can have the space to shelter from between a plurality of wavelength selection units for projection arrangement's compact structure, and then make projection arrangement's volume ratio less.

And compared with a multi-lens space folding system, the space shielding can exist among the plurality of wavelength selection units and the plurality of wavelength selection units can be arranged in parallel, so that a single free surface (the free surface is the plane where the wavelength selection units are positioned) can be used, a plurality of stereoscopic virtual images can be obtained, and the cost is saved.

Compared with the prior art, only two stereoscopic virtual images can be displayed, the light with different wavelengths can be separated by using the plurality of wavelength selection units, so that the light with different wavelengths is transmitted along different space paths, a plurality of stereoscopic virtual images are obtained, and display of a plurality of image contents can be realized.

Fig. 13 is a schematic diagram of one possible functional framework of a vehicle provided in an embodiment of the present application.

As shown in fig. 13, various subsystems may be included in the functional framework of the vehicle, such as, for example, a sensor system 12, a control system 14, one or more peripheral devices 16 (one shown), a power supply 18, a computer system 20, and a heads-up display system 32 in the illustration. Alternatively, the vehicle may also include other functional systems, such as an engine system to power the vehicle, etc., as not limited herein.

The sensor system 12 may include a plurality of sensing devices that sense the measured information and convert the sensed information to an electrical signal or other desired form of information output according to a certain rule. As illustrated, these detection devices may include, without limitation, a global positioning system (global positioning system, GPS), a vehicle speed sensor, an inertial measurement unit (inertial measurement unit, IMU), a radar unit, a laser rangefinder, an imaging device, a wheel speed sensor, a steering sensor, a gear sensor, or other elements for automatic detection, and so forth.

The control system 14 may include several elements such as a steering unit, a braking unit, a lighting system, an autopilot system, a map navigation system, a network timing system, and an obstacle avoidance system as shown. Optionally, the control system 14 may also include elements such as throttle controls and engine controls for controlling the speed of the vehicle, as the application is not limited.

Peripheral device 16 may include several elements such as the communication system in the illustration, a touch screen, a user interface, a microphone, and a speaker, among others. Wherein the communication system is used for realizing network communication between the vehicle and other devices except the vehicle. In practical applications, the communication system may employ wireless communication technology or wired communication technology to enable network communication between the vehicle and other devices. The wired communication technology may refer to communication between the vehicle and other devices through a network cable or an optical fiber, etc.

The power source 18 represents a system that provides power or energy to the vehicle, which may include, but is not limited to, a rechargeable lithium battery or lead acid battery, or the like. In practical applications, one or more battery packs in the power supply are used to provide electrical energy or power for vehicle start-up, and the type and materials of the power supply are not limited in this application.

Several functions of the vehicle are performed by the control of the computer system 20. The computer system 20 may include one or more processors 2001 (shown as one processor) and memory 2002 (which may also be referred to as storage devices). In practical applications, the memory 2002 is also internal to the computer system 20, or external to the computer system 20, for example, as a cache in a vehicle, and the present application is not limited thereto. Wherein,

the processor 2001 may include one or more general-purpose processors, e.g., a graphics processor (graphic processing unit, GPU). The processor 2001 may be used to execute related programs or instructions corresponding to the programs stored in the memory 2002 to implement the corresponding functions of the vehicle.

Memory 2002 may include volatile memory (RAM), for example; the memory may also include a non-volatile memory (ROM), flash memory (flash memory), or solid state disk (solid state drives, SSD); memory 2002 may also include combinations of the above types of memory. Memory 2002 may be used to store a set of program codes or instructions corresponding to the program codes so that processor 2001 invokes the program codes or instructions stored in memory 2002 to implement the corresponding functions of the vehicle. Including but not limited to some or all of the functions in the vehicle function frame schematic shown in fig. 13. In this application, the memory 2002 may store a set of program codes for vehicle control, which the processor 2001 invokes to control the safe driving of the vehicle, as to how the safe driving of the vehicle is achieved, as described in detail below.

Alternatively, the memory 2002 may store information such as road maps, driving routes, sensor data, and the like, in addition to program codes or instructions. The computer system 20 may implement the relevant functions of the vehicle in combination with other elements in the functional framework schematic of the vehicle, such as sensors in the sensor system, GPS, etc. For example, the computer system 20 may control the direction of travel or speed of travel of the vehicle, etc., based on data input from the sensor system 12, without limitation.

Head-up display system 32 may include several elements, such as a windshield, a controller, and the projection devices described above. The controller is used for generating an image (such as an image containing vehicle states such as vehicle speed, electric quantity/oil quantity and the like and an image of augmented reality AR content) according to a user instruction and sending the image content to the projection device; the projection device projects the light bearing the image content to a windshield, which is used for reflecting the light bearing the image content so as to enable a virtual image corresponding to the image content to be presented in front of a driver. It should be noted that the functions of some elements in the head-up display system may be implemented by other subsystems of the vehicle, for example, the controller may also be an element in the control system.

Herein, fig. 13 illustrates a system including four subsystems, the sensor system 12, the control system 14, the computer system 20, and the heads-up display system 32, by way of example only, and not by way of limitation. In practical applications, the vehicle may combine several elements in the vehicle according to different functions, thereby obtaining subsystems with corresponding different functions. In practice, the vehicle may include more or fewer systems or elements, and the present application is not limited thereto.

The terms "first," "second," and the like in this application are used for distinguishing between similar elements or items having substantially the same function and function, and it should be understood that there is no logical or chronological dependency between the terms "first," "second," and no limitation on the amount or order of execution. It will be further understood that, although the following description uses the terms first, second, etc. to describe various elements, these elements should not be limited by the terms. These terms are only used to distinguish one element from another element. For example, the first wavelength selective element may be referred to as a second wavelength selective element, and similarly, the second wavelength selective element may be referred to as a first wavelength selective element, without departing from the scope of the various examples. The first wavelength selective element and the second wavelength selective element may both be wavelength selective elements and, in some cases, may be separate and distinct wavelength selective elements.

The term "at least one" means one or more, and the term "plurality" means two or more.

The term "a and/or B" in this application includes three cases, respectively: A. b and a and B.

The foregoing description is merely a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think about various equivalent modifications or substitutions within the technical scope of the present application, and these modifications or substitutions are all covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A projection device, characterized by comprising an image providing unit (1), N wavelength selecting units (2) and a reflecting unit (3), N being larger than 1;

the image providing unit (1) is used for projecting N light beams, and different light beams correspond to different image contents;

the 1 st to the N th wavelength selection units in the N wavelength selection units (2) are sequentially arranged along the projection direction of the N light beams, the N wavelength selection units (2) are used for reflecting the N light beams to the reflection unit (3), different wavelength selection units are used for reflecting light with different wavelengths, the i th wavelength selection unit in the N wavelength selection units (2) is also used for transmitting incident light and/or reflected light of the i+1th to the N th wavelength selection units, and the i value is 1 to N-1;

The reflecting unit (3) is used for reflecting the received N light beams to form images corresponding to different image contents, and the positions of the images corresponding to the different image contents are different;

the reflecting unit (3) is a curved reflecting mirror;

wherein, when the wavelengths of the N light beams are different, the first surface of the kth wavelength selection unit in the N wavelength selection units (2) is used for reflecting the light beam of the image content corresponding to the kth wavelength selection unit, and transmitting the light beam of the image content corresponding to the kth+1th to the nth wavelength selection unit, and the value of k is at least one value from 1 to N-1;

a partial region of the second surface of the kth wavelength selective unit is configured to reflect the reflected light of the kth+1th wavelength selective unit.

2. The projection apparatus according to claim 1, wherein the incident light of the j+1th wavelength selective element of the N wavelength selective elements (2) is transmitted from the 1 st to the j th wavelength selective element in order before being incident on the j+1th wavelength selective element, and j takes a value of 1 to N-1.

3. Projection apparatus according to claim 1 or 2, characterized in that the reflected light of the j+1th wavelength selective element of the N wavelength selective elements (2) is transmitted sequentially from the j-th to the 1 st wavelength selective element before being incident on the reflecting element, j having a value of 1 to N-1.

4. Projection apparatus according to claim 1, characterized in that each of the N wavelength selective units (2) is one of a band filter, a holographic optical element HOE bulk grating or a diffractive optical element DOE; or,

the nth wavelength selection unit is a reflecting mirror, and the ith wavelength selection unit is one of a wave band filter, an HOE body grating or a DOE.

5. Projection apparatus according to claim 1 or 2, wherein, in case the wavelengths of the N light beams are the same, the (m+1) th wavelength selection unit of the N wavelength selection units (2) is configured to absorb light transmitted to the (m+1) th wavelength selection unit in the light beam of the image content corresponding to the (m) th wavelength selection unit, where m takes on at least one value of 1 to N-1.

6. Projection apparatus according to claim 5, characterized in that each of the N wavelength selective units (2) is a band filter; or,

the nth wavelength selection unit is a reflecting mirror, and the ith wavelength selection unit is a wave band filter.

7. Projection apparatus according to claim 1 or 2, wherein, in case the wavelengths of the N light beams are identical, a first surface of a kth wavelength selective element of the N wavelength selective elements (2) is configured to reflect part of the light of the image content corresponding to the kth wavelength selective element and transmit part of the light of the image content corresponding to the kth+1th to the nth wavelength selective element, k takes on at least one value of 1 to N-1;

8. The projection apparatus according to claim 1 or 2, wherein the 1 st to nth wavelength selection units are arranged in parallel in order along the projection direction of the N light beams.

9. A vehicle comprising a windscreen and a projection device as claimed in any one of claims 1 to 8;