WO2024098828A1 - Projection system, projection method, and transportation means - Google Patents

Abstract

A projection system, applied to the field of display. The projection system comprises an image generation component (101) and an optical element (102). The image generation component (101) is used for outputting two paths of imaging light. The two paths of imaging light comprise a first path of imaging light and a second path of imaging light. The first path of imaging light carries first image information. The second path of imaging light carries second image information. The optical element (102) is used for reflecting or transmitting the two paths of imaging light. The two paths of imaging light generate a virtual image on a virtual image plane (103). The two paths of imaging light are irradiated to two positions on a receiving plane (105). The distance between the two positions is m. The distance between the virtual image plane (103) and the receiving plane (105) is d1. The distance between the receiving plane (105) and a first visual plane is d2. The vergence-accommodation conflict (VAC) satisfies the following relation: VAC=|1/d2-1/d1|. The VAC is less than 0.25 diopters. By adjusting parallax information of the two pieces of image information, the visual distance d2 can be adjusted, so that the number of projection systems can be reduced, and the cost of a head-up display (HUD) can be lowered.

Description

Projection system, projection method and vehicle

This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 11, 2022, with application number CN202211414939.3 and application name “Projection System, Projection Method and Vehicle”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of display, and in particular to a projection system, a projection method and a vehicle.

Background technique

Head-up display (HUD), also known as head-up display system, is a device that projects information such as speed and navigation in front of the driver, so that the driver can see the instrument information without lowering his head. In HUD, in order to improve visual enjoyment, different image information can be projected to different distances from the driver. For example, instrument-related information is projected 2.5 meters (metre, m) away from the driver, and augmented reality (AR) information is projected 10 meters away from the driver. At this time, HUD includes two projection systems. One projection system is used to project instrument-related information. The other projection system is used to project AR information.

In practical applications, the cost of the projection system is high, which leads to the high cost of the HUD.

Summary of the invention

The present application provides a projection system, which can adjust the visual distance by adjusting the parallax information of two image information, thereby reducing the number of projection systems and reducing the cost of HUD, and can improve the user experience by controlling the convergence adjustment conflict VAC.

In a first aspect, the present application provides a projection system. The projection system includes an image generating component and an optical element. The image generating component is used to output two imaging lights. The two imaging lights include a first imaging light and a second imaging light. The first imaging light carries first image information. The second imaging light carries second image information. The optical element is used to reflect or transmit the two imaging lights, and the two imaging lights after reflection or transmission generate a virtual image on the virtual image plane. The two imaging lights after reflection or transmission are irradiated to two positions of a receiving surface. The two positions correspond to the two imaging lights one by one. The distance between the two positions is m. The distance between the virtual image plane and the receiving surface is d1. There is first parallax information between the first image information and the second image information. The first parallax information will cause the two image information viewed by the user to generate a first parallax angle, so that the image information observed by the user is located in the first visual plane. The distance between the receiving surface and the first visual plane is d2. d2 is determined based on the first parallax information between the first image information and the second image information, m and d1. The vergence accommodation conflict (VAC) satisfies the following relationship: Where VAC is less than 0.25 diopters and the units of d1 and d2 are meters.

In an optional manner of the first aspect, the optical element is a windshield, which includes a first glass layer, a second glass layer, and an intermediate layer for bonding the first glass layer and the second glass layer.

In an optional manner of the first aspect, the two imaging lights are linearly polarized lights. The intermediate layer is used to absorb the linearly polarized light. When the two imaging lights are incident on the optical element, they are reflected by two glass layers in contact with the air inside and outside the optical element, thereby forming two virtual images at the receiving position of the human eye. The two virtual images form a ghost image due to partial overlap. Ghosting can seriously affect the clarity of the HUD display and driving safety. By absorbing linearly polarized light, the impact of ghosting can be reduced, thereby improving the clarity of the HUD display and driving safety.

In an optional manner of the first aspect, the middle layer is a wedge-shaped structure. The wedge-shaped structure can reduce the impact of ghosting, thereby improving the clarity of the HUD display and driving safety.

In an optional manner of the first aspect, the value range of d1 is between 2.5 m and 7 m.

In an optional manner of the first aspect, the thickness of the intermediate layer at different positions is the same. Intermediate layers of the same thickness can reduce the cost of the optical element, thereby reducing the cost of the projection system.

In an optional manner of the first aspect, d2 is less than d1. When the thickness of the intermediate layer at different positions is the same, the projection system will form a ghost image. When d2 is less than d1, the influence of the ghost image can be reduced, thereby improving the clarity of the HUD display and driving safety.

In an optional manner of the first aspect, the value range of d1 is between 10m and 15m. When the value of d1 is too small, the impact of ghosting is relatively large. When the value of d1 is too large and VAC is less than 0.25 diopters, the value of d2 is large, thereby affecting the user experience. Therefore, in the present application, by controlling the value of d1, the impact of ghosting can be reduced and the user experience can be improved.

In an optional manner of the first aspect, the first imaging light also carries third image information. The second imaging light also carries fourth image information. The distance between the receiving surface and the second visual plane is d3. d3 is a second parallax information between the third image information and the fourth image information. By carrying two sets of image information including different parallax information in two imaging lights, the two sets of image information can be projected to different distances from the driver, thereby improving user experience and reducing the cost of HUD.

In an optional manner of the first aspect, d3 is equal to d1. When d1 is equal to d3, VAC-free display can be achieved for content displayed at a close distance.

In an optional manner of the first aspect, the focal length of the optical element is f. The distance between the image generating component and the optical element is d. d is smaller than f. When d is smaller than f, the image information carried by the two imaging lights can be amplified, thereby improving the user experience.

In an optional manner of the first aspect, the distance between the virtual image plane and the optical element is d0. d0 satisfies the following formula:

In an optional manner of the first aspect, the image generating component includes a backlight component and a spatial light modulator. The backlight component is used to output two light beams to the spatial light modulator at different angles in a time-sharing manner. The spatial light modulator is used to modulate the two light beams in a time-sharing manner according to different image information to obtain two imaging lights, and output the two imaging lights at different angles. By modulating the two light beams in a time-sharing manner, the cost of the spatial light modulator can be reduced, thereby reducing the cost of the image generating component.

In an optional manner of the first aspect, the image generating component includes a backlight component, a spatial light modulator and a spectroscopic element. The backlight component is used to generate a light beam to be modulated. The spectroscopic element is used to split the light beam to be modulated to obtain two sub-beams to be modulated. The spatial light modulator is used to modulate the two sub-beams to be modulated and output two imaging lights. The spectroscopic element can reduce the refresh rate of the spatial light modulator, thereby improving the reliability of the image generating component. The spectroscopic element can be a cylindrical grating, a liquid crystal grating, a barrier grating, an electronic grating, a diffraction element, etc.

In an optional manner of the first aspect, the image generating component further includes a diffusion screen. The diffusion screen is used to receive two paths of imaging light from the spatial light modulator, diffuse the two paths of imaging light, and output the diffused two paths of imaging light at different angles.

In an optional manner of the first aspect, the two light beams include a first light beam and a second light beam. The backlight assembly is used to output the first light beam at a first position and output the second light beam at a second position. By moving the backlight assembly, the backlight assembly can output the first light beam and the second light beam through one light source, thereby reducing the cost of the backlight assembly.

In an optional manner of the first aspect, the projection system further includes a human eye tracking module and a processor. The human eye tracking module is used to obtain the position of the receiving surface. The processor is used to adjust the first parallax information of the first image information and the second image information according to the position of the receiving surface. When the distance between the human eye and the optical element changes, the value of d2 will change, which may affect the user experience. By adjusting the parallax information, the value of d2 can be controlled, thereby improving the user experience.

The second aspect of the present application provides a projection method. The projection method can be applied to a projection system. The projection method includes the following steps: the projection system outputs two imaging lights. The two imaging lights include a first imaging light and a second imaging light. The first imaging light carries the first image information. The second imaging light carries the second image information; the projection system reflects or transmits the two imaging lights, and the two imaging lights after reflection or transmission generate a virtual image on the virtual image plane. The two imaging lights after reflection or transmission are irradiated to two positions of the receiving surface. The distance between the two positions is m. The distance between the virtual image plane and the receiving surface is d1, and the distance between the receiving surface and the first visual plane is d2. d2 is determined based on the first parallax information between the first image information and the second image information, m and d1. VAC satisfies the following relationship: Among them, VAC is less than 0.25 diopters.

It should be understood that there are similarities between the projection method of the second aspect and the projection system of the first aspect. Therefore, the description of any optional manner of the second aspect can refer to the description of any optional manner of the first aspect.

The third aspect of the present application provides a vehicle, wherein the vehicle comprises a projection system as described in the first aspect or any optional manner of the first aspect, and the projection system is installed on the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a first optical path schematic diagram of a projection system provided in an embodiment of the present application;

FIG2 is a first structural schematic diagram of a windshield provided in an embodiment of the present application;

FIG3 is a second structural schematic diagram of a windshield provided in an embodiment of the present application;

FIG4 is a third structural schematic diagram of a windshield provided in an embodiment of the present application;

FIG5 is a second optical path schematic diagram of the projection system provided in an embodiment of the present application;

FIG6 is a first structural diagram of a VAC provided in an embodiment of the present application;

FIG7 is a second structural diagram of a VAC provided in an embodiment of the present application;

FIG8 is a third optical path schematic diagram of the projection system provided in an embodiment of the present application;

FIG9 is a first structural diagram of an image generation component provided in an embodiment of the present application;

FIG10 is a second structural diagram of an image generation component provided in an embodiment of the present application;

FIG11 is a third structural schematic diagram of the image generation component provided in an embodiment of the present application;

FIG12 is a circuit diagram of a projection system provided in an embodiment of the present application;

FIG13 is a schematic diagram of a projection system installed in a vehicle according to an embodiment of the present application;

FIG14 is a schematic diagram of a possible functional framework of a vehicle provided in an embodiment of the present application;

FIG. 15 is a flow chart of the projection method provided in an embodiment of the present application.

Detailed ways

The present application provides a projection system that can adjust the visual distance by adjusting the parallax information of two image information, thereby reducing the number of projection systems and reducing the cost of HUD, and by controlling the convergence adjustment conflict VAC, the user experience can be improved. It should be understood that the "first", "second", "target", etc. used in this application are only used for the purpose of distinguishing the description, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying order. In addition, for the sake of simplicity and clarity, reference numbers and/or letters are repeated in multiple figures of the present application. Repetition does not indicate a strict limiting relationship between various embodiments and/or configurations.

The projection system in this application is applied to the display field. In the display field, in order to improve visual enjoyment, the head-up display (HUD) can project different image information to different distances from the driver. At this time, the HUD includes two projection systems. One projection system is used to project instrument-related information. The other projection system is used to project augmented reality (AR) information. Therefore, the cost of HUD is relatively high.

To this end, the present application provides a projection system. FIG. 1 is a first optical path schematic diagram of a projection system provided in an embodiment of the present application. As shown in FIG. 1 , the projection system includes an image generation component 101 and an optical element 102. The image generation component 101 is used to output two imaging lights. The optical element 102 may be a reflector, a windshield, a lens or a diffraction element, etc. The optical element 102 is used to reflect or transmit two imaging lights, and there is an angle between the two imaging lights after reflection or transmission. The two imaging lights after reflection or transmission are respectively irradiated to two different positions of the receiving surface 105, such as the left eye (upper eye position) and the right eye (lower eye position) of the user. The distance between the two positions is m. The two positions correspond one to one to the two imaging lights. The position of the human eye can also be called a viewpoint. The above-mentioned projection system can provide multiple viewpoints for multiple people to watch. Correspondingly, the image generation component 101 can produce multiple groups of imaging lights for different people to watch. Among them, a group of imaging lights includes two imaging lights. This embodiment takes a viewpoint as an example, that is, the image generation component 101 generates two imaging lights as an example to illustrate the imaging process of the projection system.

The two-path imaging light includes a first path of imaging light and a second path of imaging light. The first path of imaging light carries the first image information. The second path of imaging light carries the second image information. The two paths of imaging light after reflection or transmission form a virtual image on the virtual image plane 103. For example, P1 and P2 are both image points on the virtual image plane 103. The light beams corresponding to P1 and P2 will be irradiated to different positions of the receiving surface 105. In Figure 1, the light beam corresponding to P1 belongs to the first path of imaging light. The light beam corresponding to P2 belongs to the second path of imaging light. The light beam corresponding to P1 irradiates the upper eye position of the user. The light beam corresponding to P2 irradiates the lower eye position of the user. In order to avoid crosstalk of light beams, the light beam corresponding to P1 will not irradiate the lower eye position of the user. The light beam corresponding to P2 will not irradiate the upper eye position of the user.

The distance between the virtual image plane 103 and the receiving surface 105 is d1. There is first parallax information between the first image information and the second image information. The first parallax information between the first image information and the second image information can be the distance between two pixel points in the pixel group on the virtual image plane (referred to as the first distance for short). The first image information includes N first pixel points. The second image information includes N second pixel points. N is an integer greater than 0. The N first pixel points correspond one to one with the N second pixel points. The first image information and the second image information include N pixel groups. A pixel group includes a first pixel point and a second pixel point corresponding thereto. Two pixel points in a pixel group are used to display the same point of an object. For example, both pixel points are used to display the center of a circle. For another example, both pixel points are used to display the tip of a person's nose. For another example, both pixel points are used to display the vertex of the number "1". The first distances of the N pixel groups are the same.

The first parallax information will cause the two image information viewed by the user to generate a first parallax angle. The first parallax angle is related to d1 and m. For example, in Figure 1, P1 and P2 are two pixel points in the pixel group. The distance between P1 and P2 is the first distance dm. P1, P2 and the two positions illuminated by the two imaging lights form an isosceles trapezoid. At this time, the first parallax angle β1 is obtained by dm, m and d1. The image information observed by the user is located on the visual plane 104. For example, P1 and P2 observed by the user are P10 located on the visual plane 104. The distance between the visual plane 104 and the receiving surface 105 is d2. d2 is also called the visual distance. d2, β1 and m satisfy the following relationship:

In Figure 1, the vergence accommodation conflict (VAC) satisfies the following relationship: When the VAC value is too large, the two-way imaging light will make the user dizzy, thus reducing the user experience. Therefore, in practical applications, VAC can be less than 0.25 diopters.

In the embodiment of the present application, the visual distance d2 can be adjusted by adjusting the parallax information of the two image information (the first image information and the second image information). Therefore, when the projection system in the present application is installed on a vehicle, the projection system can project different image information. To different distances from the driver. For example, the instrument-related information is projected to 2.5m away from the driver, and the AR information is projected to 10m away from the driver. Therefore, the embodiment of the present application can reduce the number of projection systems, thereby reducing the cost of the HUD. In addition, by controlling the VAC, the user experience can be improved.

According to the above description, the two imaging lights after reflection or transmission are respectively irradiated to two different positions of the receiving surface 105. The two positions correspond to two different light spots. It should be understood that m can be the center distance of the two light spots. Alternatively, when the user's eyes are located in the two positions and the two positions correspond to the eyes one by one, m can be the pupil distance of the eyes.

In practical applications, when the projection system in the present application is installed on a vehicle, the optical element 102 can be a windshield. FIG. 2 is a first structural schematic diagram of a windshield provided in an embodiment of the present application. As shown in FIG. 2 , the windshield includes a first glass layer 201, a second glass layer 203, and an intermediate layer 202. The intermediate layer 202 is used to bond the first glass layer 201 and the second glass layer 203. In FIG. 2 , the thickness of the intermediate layer 202 at different positions in the target area is the same. The target area refers to the area through which the two imaging lights pass. It should be understood that there may be processing errors in the thickness of the intermediate layer 202 at different positions. Therefore, the same thickness of the intermediate layer 202 at different positions means that the thickness deviation of the intermediate layer 202 at different positions is less than 1 mm.

In FIG2 , when any one of the two imaging lights is incident on the windshield, it will be reflected by the two glass layers in contact with the air inside and outside the windshield, thereby forming two virtual images at the receiving position of the human eye. Specifically, any one of the two imaging lights is incident on the second glass layer 203. The imaging light reflected by the second glass layer 203 is reflected to the receiving position of the human eye. The imaging light reflected by the second glass layer 203 forms a main image on the outside of the second glass layer 203. The imaging light transmitted by the second glass layer 203 reaches the first glass layer 201 after passing through the middle layer. The imaging light reflected by the first glass layer 201 is reflected to the receiving position of the human eye. The imaging light reflected by the first glass layer 201 forms a virtual image on the outside of the first glass layer 201. The virtual image and the main image are located at different positions. The two virtual images form a ghost image because of partial overlap. Ghosting will seriously affect the clarity of the HUD display and driving safety. To this end, the present application can reduce the impact of ghosting in any one or more of the following ways.

In the first mode, the two imaging lights are linearly polarized lights. The intermediate layer 202 is used to absorb the linearly polarized lights. FIG. 3 is a second structural schematic diagram of the windshield provided in an embodiment of the present application. As shown in FIG. 3 , based on FIG. 2 , any one of the two imaging lights is incident on the second glass layer 203. The imaging light reflected by the second glass layer 203 is reflected to the receiving position of the human eye. The imaging light reflected by the second glass layer 203 forms a virtual image on the outside of the second glass layer 203. The imaging light transmitted by the second glass layer 203 is absorbed by the intermediate layer 202.

In the second mode, the middle layer 202 is a wedge-shaped structure. FIG. 4 is a third structural schematic diagram of a windshield provided in an embodiment of the present application. As shown in FIG. 4, the windshield includes a first glass layer 201, a second glass layer 203 and an middle layer 202. The middle layer 202 is used to bond the first glass layer 201 and the second glass layer 203. The middle layer 202 is a wedge-shaped structure in the target area. Any one of the two imaging lights is incident on the second glass layer 203. The imaging light reflected by the second glass layer 203 is reflected to the receiving position of the human eye. The imaging light reflected by the second glass layer 203 forms a main image on the outside of the second glass layer 203. The imaging light transmitted by the second glass layer 203 reaches the first glass layer 201 after passing through the middle layer. The imaging light reflected by the first glass layer 201 is reflected to the receiving position of the human eye. The imaging light reflected by the first glass layer 201 forms a virtual image on the outside of the first glass layer 201. The virtual image and the main image are located at the same position.

In the third method, the parallax information of the two image information is controlled so that d2 is less than d1. FIG. 5 is a second optical path schematic diagram of the projection system provided in an embodiment of the present application. As shown in FIG. 5, the projection system includes an image generation component 101 and an optical element 102. The image generation component 101 is used to output two imaging lights. The optical element 102 is used to reflect or transmit the two imaging lights, and there is an angle between the two imaging lights after reflection or transmission. The two imaging lights after reflection or transmission are respectively irradiated to two different positions of the receiving surface 105. The distance between the two positions is m. The two imaging lights include a first imaging light and a second imaging light. The first imaging light carries the first image information. The second imaging light carries the second image information. The two imaging lights after reflection or transmission form a virtual image on the virtual image plane 103. For example, P1 and P2 are both image points on the virtual image plane 103. The light beams corresponding to P1 and P2 will be irradiated to different positions of the receiving surface 105. In FIG. 5, the light beam corresponding to P1 belongs to the first imaging light. The light beam corresponding to P2 belongs to the second imaging light. The light beam corresponding to P1 is irradiated to the lower eye position of the user. The light beam corresponding to P2 is irradiated to the upper eye position of the user. There is a first parallax information between the first image information and the second image information. The first parallax information causes the two image information viewed by the user to produce a first parallax angle. In FIG5 , the first parallax angle is β2. At this time, the image information observed by the user is located on the visual plane 104. For example, P1 and P2 observed by the user are P10 located on the visual plane 104.

In the description of FIG. 1 above, in order to improve the user experience, VAC can be less than 0.25 diopters. The value of VAC is related to d1 and d2. The relationship between VAC and d1 and d2 is described below in an exemplary manner.

Figure 6 is a first structural diagram of VAC provided in an embodiment of the present application. In Figure 6, the ordinate is VAC, and the unit is diopter. The abscissa is distance, and the unit is meter. Figure 6 provides 12 curves. The starting points of the curves are connected to the abscissas. The abscissa of the starting point represents d1. For example, the abscissa of the starting point of curve 601 is 4.5. 4.5 is d1 of curve 601. The abscissa of any point on curve 601 represents d2. For example, the abscissa of point 602 is 8. At this time, the ordinate of point 602 is 0.1. At this time, curve 601 and point 602 represent that when d1 is equal to 4.5 and d2 is equal to 8, VAC is equal to 0.1. It should be understood that for the description of other curves, reference can be made to the description of curve 601.

According to FIG. 6 , when VAC is less than 0.25 diopters, the value of d2 is related to the value of d1. According to the description of FIG. 1 above, d2 is the visual distance. Therefore, the value of d2 affects the user experience. In the embodiment of the present application, in order to improve the user experience, The value range of d2 can be controlled by controlling the value of d1. For example, the value range of d1 is between 2.5m and 7m, wherein d1 can be 2.5m or 7m.

FIG7 is a second schematic diagram of the structure of VAC provided in an embodiment of the present application. In FIG7 , the ordinate is VAC, in diopters. The abscissa is distance, in meters. FIG7 provides six curves. The starting points of the curves are connected to the abscissas. The abscissas of the six curves are 10, 10, 12, 12, 14 and 14, respectively. It should be understood that for the description of any of the six curves, reference may be made to the description of curve 601 in FIG6 .

In the third method described above, when the d1 value is too small, the impact of ghosting is relatively large. When the d1 value is too large and VAC is less than 0.25 diopters, the value of d2 is relatively large, thereby affecting the user experience. Therefore, in the embodiment of the present application, by controlling the value of d1, the impact of ghosting can be reduced and the user experience can be improved. For example, the value range of d1 is between 10m and 15m. Among them, d1 can be 10m or 15m.

According to the description of Figures 6 and 7, the value of d2 is related to d1. In practical applications, the value of d2 is also related to the position of the receiving plane 105. When the position of the user relative to the optical element 102 changes, the value of d2 will also change accordingly. In order to improve the user experience, the projection system may further include an eye tracking module and a processor. The personnel tracking module is used to obtain the position of the receiving surface 105. The processor is used to adjust the first parallax information of the first image information and the second image information according to the position of the receiving surface 105. By adjusting the parallax information, the value of d2 can be adjusted.

According to the foregoing description, the first imaging light of the two imaging lights can be reflected or transmitted to the left eye of the user through the optical element 102. The second imaging light of the two imaging lights can be reflected or transmitted to the right eye of the user through the optical element 102. In practical applications, different process errors exist at different positions of the optical element 102. The process error will cause the zoom factor and imaging position of the image observed by the user to have display differences relative to the ideal position, thereby reducing the user experience. Therefore, in an embodiment of the present application, image information with different parallaxes can be preprocessed. The display difference is compensated by preprocessing, thereby enhancing the display effect. For example, the processor can perform one or more of the following processing on the left eye image and/or the right eye image loaded by the image generation component 101: translate the entire or part of the left eye image or the right eye image. Enlarge or reduce the entire or part of the left eye image or the right eye image. Distort the entire or part of the left eye image or the right eye image.

In practical applications, in order to improve the user experience, the projection system can project different image information to the user at different distances in a time-sharing or simultaneous manner. This is described below.

The projection system simultaneously projects different image information to different distances from the user. FIG8 is a third optical path schematic diagram of the projection system provided in an embodiment of the present application. As shown in FIG8, based on FIG1, the first imaging light carries the first image information group. The first image information group includes the first image information and the third image information. The second imaging light carries the second image information group. The second image information group includes the second image information and the fourth image information. The two imaging lights reflected or transmitted by the optical element 102 form a virtual image on the virtual image plane 103. The virtual image also includes the first image information group and the second image information group. The different image information groups observed by the user are located in different visual planes. These are described separately below.

P1 and P2 are image points on the virtual image plane 103. The light beams corresponding to P1 and P2 will be irradiated to different positions of the receiving surface 105. In Figure 8, the light beam corresponding to P1 belongs to the first image information in the first imaging light. The light beam corresponding to P2 belongs to the second image information in the second imaging light. The light beam corresponding to P1 is irradiated to the upper eye position of the user. The light beam corresponding to P2 is irradiated to the lower eye position of the user. There is first parallax information between the first image information and the second image information. The first parallax information will cause the two image information viewed by the user to produce a first parallax angle. In Figure 8, the first parallax angle is β1. At this time, the image information observed by the user is located on the visual plane 104. P1 and P2 observed by the user are P10 located on the visual plane 104.

P3 and P4 are image points on the virtual image plane 103. The light beams corresponding to P3 and P4 will be irradiated to different positions of the receiving surface 105. In FIG8 , the light beam corresponding to P3 belongs to the third image information in the first imaging light. The light beam corresponding to P4 belongs to the fourth image information in the second imaging light. The light beam corresponding to P3 is irradiated to the upper eye position of the user. The light beam corresponding to P4 is irradiated to the lower eye position of the user. There is second parallax information between the third image information and the fourth image information. For the description of the second parallax information, reference can be made to the aforementioned description of the first parallax information. The second parallax information will cause the two image information viewed by the user to generate a second parallax angle. The second parallax angle is related to d1 and m. In FIG8 , the second parallax angle is β3. The distance between the visual plane 801 and the receiving surface 105 is d3. d3 is determined based on the second parallax information, m and d1 between the third image information and the fourth image information. At this time, the image information observed by the user is located on the visual plane 801. For example, P3 and P4 observed by the user are P11 located on the visual plane 801.

The projection system projects different image information to different distances from the user in a time-sharing manner. For example, as shown in FIG8 , at the first moment, the first imaging light output by the image generation component 101 carries the first image information. The second imaging light output by the image generation component 101 carries the second image information. The two imaging lights reflected or transmitted by the optical element 102 form a virtual image on the virtual image plane 103. There is first parallax information between the first image information and the second image information. At this time, the image information observed by the user is located on the visual plane 104. For example, P1 and P2 observed by the user on the virtual image plane 103 are P10 located on the visual plane 104. At the second moment, the first imaging light output by the image generation component 101 carries the third image information. The second imaging light output by the image generation component 101 carries the fourth image information. After being reflected by the optical element 102 Or the two imaging lights after transmission form a virtual image on the virtual image plane 103. The third image information and the fourth image information have second parallax information. At this time, the image information observed by the user is located on the visual plane 801. For example, P3 and P4 observed by the user on the virtual image plane 103 are P11 located on the visual plane 801. The first moment and the second moment are alternately distributed. At this time, the projection system projects different image information to different distances of the user in a time-sharing manner.

It should be understood that the aforementioned FIG. 8 is only an example of a projection system provided by an embodiment of the present application. In practical applications, those skilled in the art can design a projection system according to requirements. For example, in FIG. 8, d3 and d2 are greater than d1. In practical applications, d3 and/or d2 may be less than d1. For another example, the first imaging light and the second imaging light may also carry more image information. More image information corresponds to more visual planes.

It should be understood that in the embodiment of the present application, the third image information and the fourth image information can be used to form a 3D image, or can be used to form a 2D image. When the third image information and the fourth image information are used to form a 2D image, d2 or d3 can be equal to d1.

FIG9 is a first structural schematic diagram of an image generation component provided by an embodiment of the present application. As shown in FIG9 , the image generation component 101 includes a backlight component 901 and a spatial light modulator 902. The backlight component 901 is used to output two light beams to the spatial light modulator 902 at different angles in a time-sharing manner. The spatial light modulator 103 can be a liquid crystal display (LCD), liquid crystal on silicon (LCOS), a digital micro-mirror device (DMD), or a micro-electro-mechanical system (MEMS). The spatial light modulator 902 is used to modulate the two light beams in a time-sharing manner according to different image information to obtain two imaging lights, and output the two imaging lights at different angles. For example, at a first moment, the spatial light modulator 103 is used to modulate the first light beam according to the first image information to obtain the first imaging light. At a second moment, the spatial light modulator 103 is used to modulate the second light beam according to the second image information to obtain the second imaging light. For the description of the two-path imaging light, reference may be made to the description in the aforementioned FIG. 1, FIG. 5 or FIG. 8. For example, the two-path imaging light is irradiated to the optical element. The two-path imaging light reflected or transmitted by the optical element is irradiated to different viewpoints respectively. In the embodiment of the present application, by modulating the two light beams in a time-sharing manner, the cost of the spatial light modulator 902 can be reduced, thereby reducing the cost of the image generation component 101. In addition, the image generation component can also be a display that does not require a backlight, such as an organic light-emitting diode (OLED) display or a Micro LED.

FIG10 is a second structural schematic diagram of an image generating assembly provided in an embodiment of the present application. As shown in FIG10 , the image generating assembly 101 includes a backlight assembly 901 and a spatial light modulator 902. The backlight assembly 901 moves between position A and position B. The backlight assembly 901 is used to output a first light beam at a first position (position A) and output a second light beam at a second position (position B). It should be understood that the mobile backlight assembly 901 may be a partial device in the mobile backlight assembly 901. For example, the backlight assembly 901 includes a light source device and a non-fixed element. The non-fixed element may be a lens, a reflector, a prism, or a Fresnel mirror, etc. The backlight assembly 901 may output two light beams in a time-sharing manner by moving the non-fixed element. In an embodiment of the present application, by moving the backlight assembly, the backlight assembly may output the first light beam and the second light beam through one light source, thereby reducing the cost of the backlight assembly.

FIG11 is a third structural schematic diagram of the image generation component provided in an embodiment of the present application. As shown in FIG11, based on FIG9 or FIG10, the image generation component 101 also includes a lens 1101 and a diffuser screen 1102. The spatial light modulator 902 is used to output two paths of imaging light to the lens 1101 at different angles. The lens 1101 is used to change the transmission direction of the two paths of imaging light and transmit the two paths of transmission light to the diffuser screen 1102. The diffuser screen 1102 is used to diffuse the two paths of imaging light and output the diffused two paths of imaging light at different angles. The diffused two paths of imaging light can be irradiated to different viewpoints through optical elements.

According to the description of the aforementioned FIG. 8 , the embodiment of the present application can project different image information to different distances from the user in a time-sharing manner. Specifically, the first imaging light at the first moment carries the first image information. The second imaging light at the first moment carries the second image information. The first imaging light at the second moment carries the third image information. The second imaging light at the first moment carries the fourth image information. In practical applications, combined with the relevant description of FIG. 9 , the projection system can project different image information to different distances from the user in another time-sharing manner. Specifically, the first imaging light at the first moment carries the first image information and the third image information. The second imaging light at the second moment carries the second image information and the fourth image information.

As shown in Figure 1, the focal length of the optical element 102 is f. The distance between the image plane of the image generating component 101 (the display surface of the image) and the optical element 102 is d. The image plane of the image generating component 101 can be a pixel component or a diffusion screen. There is a vertical distance between each point on the optical element 102 and the image plane of the image generating component 101. d can be the farthest vertical distance between the optical element 102 and the image plane of the image generating component 101. Alternatively, d can be the straight-line distance between the central pixel of the image plane of the image generating component 101 and the target point on the optical element 102. The central pixel is one or more pixels at the center position of the image plane. The imaging light output by the central pixel irradiates the target point on the optical element 102. The distance between the virtual image formed by the two imaging lights after reflection or transmission and the optical element is d0, that is, the distance between the virtual image plane 103 and the optical element 102 is d0. d0, d and f satisfy the following formula: In the embodiment of the present application, d may be smaller than f. When d is smaller than f, the optical element 102 may magnify the virtual image. Therefore, when the distance between the user and the optical element 102 is relatively close, the user may see to an enlarged virtual image, thereby improving the user experience.

In practical applications, the optical element 102 reflects or transmits two imaging lights through the reflection or transmission area. The target point may refer to any point in the reflection or transmission area. Alternatively, the optical element 102 reflects or transmits two imaging lights through two reflection or transmission areas. The two imaging lights correspond to the reflection or transmission areas one by one. The target point may refer to the center point between the two reflection or transmission areas.

Refer to FIG. 12 , which is a circuit diagram of a projection system provided in an embodiment of the present application.

As shown in FIG. 12 , the circuit in the projection system mainly includes a processor 1001, an internal memory 1002, an external memory interface 1003, an audio module 1004, a video module 1005, a power module 1006, a wireless communication module 1007, an I/O interface 1008, a video interface 1009, a Controller Area Network (CAN) transceiver 1010, a display circuit 1028, and a display panel 1029. The processor 1001 and its peripheral components, such as the internal memory 1002, the CAN transceiver 1010, the audio module 1004, the video module 1005, the power module 1006, the wireless communication module 1007, the I/O interface 1008, the video interface 1009, the touch unit 1010, and the display circuit 1028 can be connected through a bus. The processor 1001 can be called a front-end processor.

In addition, the circuit diagrams shown in the embodiments of the present application do not constitute a specific limitation on the projection system. In other embodiments of the present application, the projection system may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

The processor 1001 includes one or more processing units, for example, the processor 1001 may include an application processor (AP), a modem processor, a graphics processor (GPU), an image signal processor (ISP), a video codec, a digital signal processor (DSP), a baseband processor, and/or a neural network processor (NPU), etc. Different processing units may be independent devices or integrated in one or more processors.

A memory may also be provided in the processor 1001 for storing instructions and data. For example, the operating system of the projection system, the AR Creator software package, etc. may be stored. In some embodiments, the memory in the processor 1001 is a cache memory. The memory may store instructions or data that the processor 1001 has just used or cyclically used. If the processor 1001 needs to use the instruction or data again, it may be directly called from the memory. Repeated access is avoided, the waiting time of the processor 1001 is reduced, and the efficiency of the system is improved.

In addition, if the projection system in this embodiment is installed on a vehicle, the functions of the processor 1001 can be implemented by a domain processor on the vehicle.

In some embodiments, the projection system may further include a plurality of input/output (I/O) interfaces 1008 connected to the processor 1001. The interface 1008 may include, but is not limited to, an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver/transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input/output (GPIO) interface, a subscriber identity module (SIM) interface, and/or a universal serial bus (USB) interface, etc. The I/O interface 1008 may be connected to devices such as a mouse, touch screen, keyboard, camera, speaker, microphone, etc., and may also be connected to physical buttons on the projection system (such as volume buttons, brightness adjustment buttons, power buttons, etc.).

The internal memory 1002 can be used to store computer executable program codes, which include instructions. The internal memory 1002 may include a program storage area and a data storage area. The program storage area may store an operating system, an application required for at least one function (such as a call function, a time setting function, an AR function, etc.), etc. The data storage area may store data created during the use of the projection system (such as a phone book, world time, etc.), etc. In addition, the internal memory 1002 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (Universal Flash Storage, UFS), etc. The processor 1001 executes various functional applications and data processing of the projection system by running instructions stored in the internal memory 1002 and/or instructions stored in a memory provided in the processor 1001.

The external memory interface 1003 can be used to connect an external memory (such as a Micro SD card). The external memory can store data or program instructions as needed, and the processor 1001 can perform operations such as reading and writing these data or programs through the external memory interface 1003.

The audio module 1004 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. The audio module 1004 can also be used to encode and decode audio signals, such as playing or recording. In some embodiments, the audio module 1004 can be arranged in the processor 1001, or some functional modules of the audio module 1004 can be arranged in the processor 1001. The projection system can realize audio functions through the audio module 1004 and the application processor.

The video interface 1009 can receive external audio and video input, which can be a high-definition multimedia interface (HDMI), a digital visual interface (DVI), a video graphics array (VGA), a display port (DP), a low voltage differential signal (LVDS) interface, etc. The video interface 1009 can also output video to the outside. For example, the projection system receives the audio and video input through the video interface. The video data sent by the navigation system or the video data sent by the receiving domain processor.

The video module 1005 can decode the video input by the video interface 1009, for example, by performing H.264 decoding. The video module can also encode the video collected by the projection system, for example, by performing H.264 encoding on the video collected by the external camera. In addition, the processor 1001 can also decode the video input by the video interface 1009, and then output the decoded image signal to the display circuit.

Furthermore, the stereoscopic projection system further includes a CAN transceiver 1010, which can be connected to the CAN bus (CAN BUS) of the car. Through the CAN bus, the stereoscopic projection system can communicate with the in-vehicle entertainment system (music, radio, video module), the vehicle status system, etc. For example, the user can turn on the in-vehicle music playback function by operating the projection system. The vehicle status system can send vehicle status information (doors, seat belts, etc.) to the stereoscopic projection system for display.

The display circuit 1028 and the display panel 1029 jointly realize the function of displaying an image. The display circuit 1028 receives the image signal output by the processor 1001, processes the image signal and then inputs it into the display panel 1029 for imaging. The display circuit 1028 can also control the image displayed by the display panel 1029. For example, it controls parameters such as display brightness or contrast. Among them, the display circuit 1028 may include a driving circuit, an image control circuit, etc. Among them, the above-mentioned display circuit 1028 and the display panel 1029 may be located in the pixel component 502.

The display panel 1029 is used to modulate the light beam input by the light source according to the input image signal, so as to generate a visible image. The display panel 1029 can be a liquid crystal on silicon panel, a liquid crystal display panel or a digital micromirror device.

In this embodiment, the video interface 1009 can receive input video data (or called a video source), and the video module 1005 decodes and/or digitally processes the data and outputs an image signal to the display circuit 1028. The display circuit 1028 drives the display panel 1029 to image the light beam emitted by the light source according to the input image signal, thereby generating a visible image (emitting imaging light).

The power module 1006 is used to provide power to the processor 1001 and the light source according to the input power (e.g., direct current), and the power module 1006 may include a rechargeable battery, which can provide power to the processor 1001 and the light source. The light emitted by the light source can be transmitted to the display panel 1029 for imaging, thereby forming an image light signal (imaging light).

In addition, the power module 1006 can be connected to a power module of a car (eg, a power battery), and the power module of the car supplies power to the power module 1006 of the projection system.

The wireless communication module 1007 enables the projection system to communicate wirelessly with the outside world, and can provide wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared (IR) and other wireless communication solutions. The wireless communication module 1007 can be one or more devices integrating at least one communication processing module. The wireless communication module 1007 receives electromagnetic waves via an antenna, modulates the frequency of the electromagnetic wave signal and performs filtering, and sends the processed signal to the processor 1001. The wireless communication module 1007 can also receive the signal to be sent from the processor 1001, modulate the frequency of the signal, amplify it, and convert it into electromagnetic waves for radiation through the antenna.

In addition, in addition to being input through the video interface 1009, the video data decoded by the video module 1005 can also be wirelessly received through the wireless communication module 1007 or read from the internal memory 1002 or the external memory. For example, the projection system can receive video data from the terminal device or the in-vehicle entertainment system through the wireless LAN in the car, and the projection system can also read the audio and video data stored in the internal memory 1002 or the external memory.

The embodiment of the present application also provides a vehicle, which is equipped with any of the aforementioned stereoscopic projection systems. The projection system is used to output two imaging lights. The two imaging lights carry different image information. The two output imaging lights are illuminated to the receiving surface through the windshield to form a virtual image. The virtual image is located on one side of the windshield, and the driver or passenger is located on the other side of the windshield. The two imaging lights after reflection or transmission are respectively irradiated to the eyes of the driver or the passenger. For example, the first imaging light is irradiated to the left eye of the passenger. The second imaging light is irradiated to the right eye of the passenger.

The embodiment of the present application also provides a vehicle, which is equipped with the projection system in Figures 1, 5, 8 or 12 above. Figure 13 is a schematic diagram of the projection system installed in a vehicle provided in the embodiment of the present application. The windshield of the vehicle can be used as an optical element in the projection system. The image generation component 101 in the projection system is located on the same side of the windshield. The image generation component 101 is used to output two imaging lights. The two imaging lights carry different image information. The windshield is used to reflect or transmit the two imaging lights to form a virtual image. The virtual image is located on one side of the windshield, and the driver or passenger is located on the other side of the windshield. The two imaging lights after reflection or transmission are respectively irradiated to the eyes of the driver or the passenger. For example, the first imaging light is irradiated to the left eye of the passenger. The second imaging light is irradiated to the right eye of the passenger.

Exemplarily, the vehicle can be a car, truck, motorcycle, bus, ship, airplane, helicopter, lawn mower, recreational vehicle, amusement park vehicle, construction equipment, tram, golf cart, train, and cart, etc., which are not particularly limited in the embodiments of the present application. The projection system can be installed on the instrument panel (IP) of the vehicle, located at the co-pilot position or the main driver position, or it can be installed on the back of the seat. When the above-mentioned projection system is applied to a vehicle, it can be called HUD, which can be used to display navigation information, vehicle speed, power/fuel level, etc.

FIG. 14 is a schematic diagram of a possible functional framework of a vehicle provided in an embodiment of the present application.

As shown in FIG14 , the functional framework of the vehicle may include various subsystems, such as the control system 14, the sensor system 12, one or more peripheral devices 16 (one is shown as an example), the power supply 18, the computer system 20, and the display system 32. Optionally, the vehicle may also include other functional systems, such as an engine system that provides power for the vehicle, etc., which is not limited in this application.

Among them, the sensor system 12 may include several detection devices, which can sense the measured information and convert the sensed information into electrical signals or other required forms of information output according to certain rules. As shown in the figure, these detection devices may include a global positioning system (GPS), a vehicle speed sensor, an inertial measurement unit (IMU), a radar unit, a laser rangefinder, a camera device, a wheel speed sensor, a steering sensor, a gear position sensor, or other components for automatic detection, etc., and this application does not limit them.

The control system 14 may include several components, such as the steering unit, brake unit, lighting system, automatic driving system, map navigation system, network timing system and obstacle avoidance system shown in the figure. Optionally, the control system 14 may also include components such as a throttle processor and an engine processor for controlling the vehicle's speed, which are not limited in this application.

The peripheral device 16 may include several components, such as the communication system, touch screen, user interface, microphone, and speaker shown in the figure. The communication system is used to realize network communication between the vehicle and other devices other than the vehicle. In practical applications, the communication system may use wireless communication technology or wired communication technology to realize network communication between the vehicle and other devices. The wired communication technology may refer to communication between the vehicle and other devices through network cables or optical fibers.

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

Several functions of the vehicle are controlled and implemented by the computer system 20. The computer system 20 may include one or more processors 2001 (one processor is shown as an example) and a memory 2002 (also referred to as a storage device). In actual applications, the memory 2002 is also inside the computer system 20, or it may be outside the computer system 20, for example, as a cache in the vehicle, etc., which is not limited in this application.

For the description of processor 2001, reference may be made to the description of processor 1001 in FIG. 12 . Processor 2001 may include one or more general-purpose processors, such as a graphics processing unit (GPU). Processor 2001 may be used to run the relevant programs or instructions corresponding to the programs stored in memory 2002 to implement the corresponding functions of the vehicle.

The memory 2002 may include a volatile memory, such as a RAM; the memory may also include a non-volatile memory, such as a ROM, a flash memory or a solid state drive (SSD); the memory 2002 may also include a combination of the above-mentioned types of memories. The memory 2002 may be used to store a set of program codes or instructions corresponding to the program codes, so that the processor 2001 calls the program codes or instructions stored in the memory 2002 to implement the corresponding functions of the vehicle. The function includes but is not limited to some or all of the functions in the vehicle function framework diagram shown in FIG13. In the present application, a set of program codes for vehicle control may be stored in the memory 2002, and the processor 2001 calls the program codes to control the safe driving of the vehicle. How to achieve safe driving of the vehicle is specifically described in detail below in the present application.

Optionally, in addition to storing program codes or instructions, the memory 2002 may also store information such as road maps, driving routes, sensor data, etc. The computer system 20 may be combined with other elements in the vehicle functional framework diagram, such as sensors in the sensor system, GPS, etc., to implement relevant functions of the vehicle. For example, the computer system 20 may control the driving direction or driving speed of the vehicle based on the data input from the sensor system 12, which is not limited in this application.

The display system 32 may include several components, such as a processor, an optical element, and the stereoscopic projection system 100 described above. The processor is used to generate images according to user instructions (such as generating images containing vehicle status such as vehicle speed, power/fuel level, and images of augmented reality AR content), and send the image content to the stereoscopic projection system 100. The stereoscopic projection system 100 is used to output two-way imaging light carrying different image information. The windshield is an optical element. The windshield is used to reflect or transmit two-way imaging light so that a virtual image corresponding to the image content is presented in front of the driver or passenger. It should be noted that the functions of some components in the display system 32 can also be implemented by other subsystems of the vehicle. For example, the processor can also be a component in the control system 14.

Among them, FIG. 14 of the present application includes four subsystems, and the sensor system 12, the control system 14, the computer system 20 and the display system 32 are only examples and do not constitute limitations. In actual applications, vehicles can combine several components in the vehicle according to different functions to obtain subsystems with corresponding different functions. In actual applications, vehicles can include more or fewer systems or components, and this application does not limit them.

FIG15 is a flow chart of a projection method provided in an embodiment of the present application. The projection method can be applied to a projection system or a vehicle equipped with a projection system. Here, the projection method is described by taking the application of the projection method to the projection system as an example. As shown in FIG15, the projection method includes the following steps: Steps.

In step 1501, the projection system outputs two paths of imaging light. The two paths of imaging light include a first imaging light and a second imaging light. The first imaging light carries first image information, and the second imaging light carries second image information.

For the description of the projection system, reference may be made to the description in any of the aforementioned Figures 1 to 12. For example, the projection system includes an image generating component 101 and an optical element 102. The projection system outputs two paths of imaging light through the image generating component 101. For another example, the image generating component 101 includes a backlight component 901 and a spatial light modulator 902. The backlight component 901 is used to output two light beams to the spatial light modulator 902 at different angles in a time-sharing manner. The spatial light modulator 902 is used to modulate the two light beams in a time-sharing manner according to different image information to obtain two paths of imaging light.

In step 1502, the projection system reflects or transmits two imaging lights. The two imaging lights after reflection or transmission generate a virtual image on the virtual image plane. The two imaging lights are respectively irradiated to two positions of the receiving surface. The distance between the two positions is m. The distance between the virtual image plane and the receiving surface is d1. The distance between the receiving surface and the first visual plane is d2. d2 is determined based on the first parallax information between the first image information and the second image information, m and d1. d1 and d2 meet the first condition.

The two paths of imaging light after reflection or transmission are respectively irradiated to different positions of the receiving surface 105, such as the left eye (upper eye position) and the right eye (lower eye position) of the user. The two paths of imaging light after reflection or transmission generate a virtual image on the virtual image plane 103. The virtual image plane 103 is located on one side of the optical element 102, and the receiving surface 105 is located on the other side of the optical element 102. There is first parallax information between the first image information and the second image information. The first parallax information will cause the two image information viewed by the user to produce a first parallax angle. At this time, the image information observed by the user is located on the visual plane 104. The distance between the visual plane 104 and the receiving surface 105 is d2. d1 and d2 meet the first condition, and the first condition can be any one or more of the following conditions.

1. d2 is smaller than d1. When the optical element is a windshield, the projection system may form a ghost image. The ghost image will affect the clarity of the HUD display and driving safety. When d2 is smaller than d1, the impact of the ghost image can be reduced, thereby improving the clarity of the HUD display and driving safety.

2, VAC is less than 0.25 diopters. The VAC size is negatively correlated with the user experience. By controlling VAC, the user experience can be improved.

It should be understood that there are similarities between the content of the projection method and the content of the aforementioned projection system. Therefore, for the description of the projection method, reference may be made to the relevant description in the aforementioned projection system. For example, in step 1501, the projection system outputs two light beams in a time-sharing manner, and obtains two imaging lights by modulating the two light beams in a time-sharing manner. For another example, in step 1501, the projection system outputs two imaging lights at a first moment. The first imaging light in the two imaging lights carries the first image information. The second imaging light in the two imaging lights carries the second image information. The first image information and the second image information carry the first parallax information. The projection method further includes the following steps: the projection system outputs two imaging lights at a second moment. The first imaging light in the two imaging lights carries the third image information. The second imaging light in the two imaging lights carries the fourth image information. The third image information and the fourth image information carry the second parallax information.

It should be understood that in the description of this specification, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner. The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims (18)

1. A projection system, characterized in that it comprises an image generating component and an optical element, wherein:

   The image generating component is used to output two paths of imaging light, wherein the two paths of imaging light include a first path of imaging light and a second path of imaging light, wherein the first path of imaging light carries first image information, and the second path of imaging light carries second image information;

   The optical element is used to reflect or transmit the two imaging lights, the two imaging lights after reflection or transmission generate a virtual image on the virtual image plane, and the two imaging lights after reflection or transmission are irradiated to two positions of the receiving surface, and the distance between the two positions is m;

   The distance between the virtual image plane and the receiving plane is d1, and the distance between the receiving plane and the first visual plane is d2, wherein d2 is determined according to the first parallax information between the first image information and the second image information, m and d1, and the convergence accommodation conflict VAC satisfies the following relationship:
   

   Wherein, the VAC is less than 0.25 diopters.
2. The projection system according to claim 1, characterized in that the optical element is a windshield, and the windshield comprises a first glass layer, a second glass layer, and an intermediate layer bonding the first glass layer and the second glass layer.
3. The projection system according to claim 2, characterized in that the two paths of imaging light are linearly polarized light, and the intermediate layer is used to absorb the linearly polarized light.
4. The projection system according to claim 2, characterized in that the intermediate layer is a wedge-shaped structure.
5. The projection system according to claim 3 or 4, characterized in that the value range of d1 is between 2.5m and 7m.
6. The projection system according to claim 2, characterized in that the thickness of the intermediate layer at different positions is the same.
7. The projection system according to claim 6, wherein d2 is smaller than d1.
8. The projection system according to claim 7, characterized in that the value range of d1 is between 10m and 15m.
9. The projection system according to any one of claims 1 to 8, characterized in that the first imaging light also carries third image information, the second imaging light also carries fourth image information, the distance between the receiving surface and the second visual plane is d3, and d3 is determined based on the second parallax information between the third image information and the fourth image information, m and d1.
10. The projection system according to claim 9, characterized in that d3 is equal to d1.
11. The projection system according to any one of claims 1 to 10, characterized in that the focal length of the optical element is f, the distance between the image generating component and the optical element is d, and d is smaller than f.
12. The projection system according to claim 11, characterized in that the distance between the virtual image plane and the optical element is d0, and d0 satisfies the following formula:
    
13. The projection system according to any one of claims 1 to 12, characterized in that the image generating component comprises a backlight component and a spatial light modulator;

    The backlight assembly is used to output two light beams to the spatial light modulator at different angles in a time-sharing manner;

    The spatial light modulator is used to modulate the two light beams in a time-sharing manner according to different image information to obtain the two paths of imaging light, and output the two paths of imaging light at different angles.
14. The projection system according to claim 13, wherein the image generating component further comprises a diffusion screen;

    The diffusion screen is used to receive the two paths of imaging light from the spatial light modulator, diffuse the two paths of imaging light, and output the diffused two paths of imaging light at different angles.
15. The projection system according to claim 13 or 14, characterized in that the two light beams include a first light beam and a second light beam;

    The backlight assembly is used to output two light beams to the spatial light modulator at different angles in a time-sharing manner, including: the backlight assembly is used to output the first light beam at a first position, and output the second light beam at a second position.
16. The projection system according to any one of claims 1 to 15, characterized in that the projection system further comprises an eye tracking module and a processor;

    The personnel tracking module is used to obtain the position of the receiving surface;

    The processor is used to adjust the first disparity information of the first image information and the second image information according to the position of the receiving surface.
17. A projection method, characterized by comprising:

    Outputting two paths of imaging light, the two paths of imaging light comprising a first path of imaging light and a second path of imaging light, the first path of imaging light carrying first image information, and the second path of imaging light carrying second image information;

    The two imaging lights are reflected or transmitted, and the two imaging lights after reflection or transmission generate a virtual image on the virtual image surface. The two paths of imaging light are irradiated to two positions of the receiving surface, the distance between the two positions is m, the distance between the virtual image plane and the receiving surface is d1, the distance between the receiving surface and the first visual plane is d2, d2 is determined according to the first parallax information between the first image information and the second image information, m and d1, and the convergence accommodation conflict VAC satisfies the following relationship:
    

    Wherein, the VAC is less than 0.25 diopters.
18. A vehicle, characterized in that it comprises the projection system according to any one of claims 1 to 16, wherein the projection system is installed on the vehicle.