Display module, optical display system, terminal equipment and image display method

Abstract

The invention discloses a display module, an optical display system, terminal equipment and an image display method. The method can be applied to the fields of head-up display (HUD) equipment, near-to-eye display (NED) equipment, displays or vehicle-mounted display screens and the like. The display module comprises a scattering layer and a reflecting layer. The scattering layer is used for receiving different image light from the image generation unit and scattering the different image light to corresponding positions of the reflecting layer, and the image light carries image information; and the reflecting layer is used for reflecting the image light from the corresponding position of the scattering layer to a corresponding viewpoint and transmitting ambient light. Through cooperation of the scattering layer and the reflecting layer, different image light can be reflected to corresponding viewpoints, so that a 3D image can be formed. Moreover, since the reflecting layer can transmit ambient light, 3D transparent display can be realized based on the display module.

Description

Display module, optical display system, terminal device and image display method Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display module, an optical display system, a terminal device, and an image display method. Background Art

[0002] With the development of display technology, transparent displays are becoming increasingly popular. Transparent displays do not affect the user's ability to observe ambient light, while still being able to display image information. Transparent displays are primarily categorized as active luminescence and projection-based. Active luminescence, for example, utilizes organic light-emitting diode (OLED) technology. Projection-based displays, for example, incorporate scattering particles or phosphors into the windshield or window glass. When illuminated by a light source, the windshield with these scattering particles or phosphors emits light, producing an image. By controlling the concentration of the scattering particles or imparting wavelength selectivity to the scattering particles, the windshield's transparency to ambient light can be maintained, thus achieving a transparent display.

[0003] Currently, three-dimensional (3D) displays can give viewers a strong sense of three-dimensional realism, increase depth of field, and enhance the richness of displayed content. The display device emits left and right image light with different polarization states. When a user wears polarized glasses, the left and right lenses only allow light with corresponding polarization states to enter. As a result, the left and right eyes perceive different images, which are then fused by the brain to form 3D vision.

[0004] However, existing 3D displays require external tools (such as polarized glasses) to be implemented, and cannot achieve 3D transparent display.

[0005] Summary of the Invention

[0006] The present application provides a display module, an optical display system, a terminal device and an image display method for realizing 3D transparent display.

[0007] In a first aspect, the present application provides a display module comprising a scattering layer and a reflective layer. The scattering layer is configured to receive different image lights from a picture generation unit (PGU) and scatter the different image lights to corresponding positions on the reflective layer, wherein the image lights carry image information. The reflective layer is configured to reflect the image lights from corresponding positions on the scattering layer to corresponding viewpoints and transmit ambient light.

[0008] Based on the above solution, the scattering layer and the reflective layer can be used to reflect different image lights to corresponding viewpoints, thereby forming a 3D image. Furthermore, because the reflective layer can also transmit ambient light, this display module can achieve 3D transparent display.

[0009] Different image lights carry different image information. Furthermore, the deflection states of different image lights can be the same or different.

[0010] In a possible implementation, the reflective layer includes an array of concave cylindrical reflectors, and the surfaces of the concave cylindrical reflectors in the array close to the scattering layer are concave surfaces, and the concave surfaces are covered with a reflective film.

[0011] By making the surfaces of the concave cylindrical reflectors in the concave cylindrical reflector array close to the scattering layer concave, an image formed based on the image light from the scattering layer can have parallax and stereoscopic effect.

[0012] It is understandable that, without affecting the 3D transparent display, non-concave cylindrical reflectors may exist in the concave cylindrical reflector array.

[0013] In a possible implementation manner, the projection of the concave surface close to the scattering layer on at least a first plane is an arc, wherein the first plane is, for example, a horizontal plane.

[0014] By arranging the projection of the concave surface close to the scattering layer on at least the first plane to be an arc, the image formed by the image light can have parallax and stereoscopic effect in the first direction parallel to the first plane.

[0015] In a possible implementation, the reflectivity of the reflective film is greater than a first reflectivity threshold and less than a second reflectivity threshold.

[0016] By setting the reflectivity of the reflective film to be greater than the first reflectivity threshold and less than the second reflectivity threshold, the reflective film can both reflect image light from the scattering layer and transmit ambient light, thereby achieving 3D transparent display.

[0017] In a possible implementation, the reflectivity of the reflective film is related to the transmittance requirement of the reflective film.

[0018] By setting the reflectivity of the reflective film in relation to the required transmittance of the reflective film, the application scenario requirements of the real module can be met. For example, when the display module is installed on a windshield, the transmittance of the windshield needs to be greater than 70%. Therefore, the transmittance of the reflective film needs to be greater than 70%. Correspondingly, the reflectivity of the reflective film needs to be less than 30% and greater than 0.

[0019] In a possible implementation, the reflective film includes a nanometal film or a dielectric film.

[0020] In a possible implementation, the concave surface is filled with a filler, and the refractive index of the filler and the refractive index of the concave cylindrical reflector meet a preset error requirement.

[0021] In a possible implementation, the refractive index of the filler is the same as the refractive index of the concave cylindrical reflector.

[0022] Exemplarily, the material of the filler is the same as that of the concave cylindrical reflector.

[0023] By filling the concave surface of the concave cylindrical reflector with a filler whose refractive index meets a preset error requirement with the refractive index of the concave cylindrical reflector, the display module does not affect the propagation direction of ambient light, thereby achieving better transparent display.

[0024] In a possible implementation, the concave cylindrical reflector array is a one-dimensional array, one concave cylindrical reflector in the concave cylindrical reflector array corresponds to N columns of regions of the scattering layer, the N columns of regions are used to receive different image lights, and N is an integer greater than 1.

[0025] By arranging a concave cylindrical reflector corresponding to more than two columns of areas of the scattering layer, the display module can produce a 3D transparent display with a stronger stereoscopic effect.

[0026] In a possible implementation, the concave cylindrical reflector array is a two-dimensional array, and one concave cylindrical reflector in the concave cylindrical reflector array corresponds to one area of ​​the scattering layer.

[0027] Through the two-dimensional concave cylindrical reflector array, the image formed by the image light has parallax and stereoscopic effect in the first direction, and also has parallax and stereoscopic effect in the second direction.

[0028] In a possible implementation, the reflective layer includes a holographic reflective medium layer. Further, the holographic reflective medium layer is manufactured by holographic exposure.

[0029] By using the holographic reflective medium layer as the reflective layer, the thickness of the display module can be reduced, thereby contributing to making the display module lighter and thinner.

[0030] In a possible implementation, the incident angle of the image light scattered to the corresponding position of the reflective layer into the scattering layer falls within a preset angle range.

[0031] By setting the scattering layer to have angle selectivity, the scattering layer can only scatter light that meets a preset angle range and is transparent to ambient light entering from other directions. In this way, the display module can achieve 3D transparent display.

[0032] In a possible implementation manner, the scattering layer is obtained by holographic exposure.

[0033] The scattering layer is fabricated using a holographic exposure method. During exposure, the reference laser and the image light emitted by the image generation unit have the same field of view and angle of incidence. This ensures that only image light with the same field of view and angle of incidence can excite the scattering layer. Ambient light, which does not meet the scattering layer's angle selection requirements, is directly transmitted. Display modules based on this scattering layer have high transparency.

[0034] In a second aspect, the present application provides an optical display system, which includes an image generating unit and the above-mentioned first aspect or any one of the display modules in the first aspect; the image generating unit is used to emit different image lights.

[0035] In a possible implementation manner, the polarization states of different image lights emitted by the image generating unit are the same.

[0036] Exemplarily, the image generating unit includes but is not limited to a projector.

[0037] In a third aspect, the present application provides a terminal device, which includes the above-mentioned second aspect or any one of the optical display systems in the second aspect, and the optical display system is installed on the terminal device.

[0038] The technical effects that can be achieved in any of the second and third aspects mentioned above can refer to the description of the beneficial effects in the first aspect mentioned above, and will not be repeated here.

[0039] In a fourth aspect, the present application provides an image display method, the method comprising: obtaining the coordinates of a first viewpoint and / or a second viewpoint; determining K eye relief distances based on the coordinates of the first viewpoint and / or the second viewpoint and the coordinates of K target positions of the display area of ​​the windshield, the K target positions corresponding one-to-one to K rows of the image projected onto the display area, and the parallax between the first viewpoint and the second viewpoint, the eye relief distance, and the virtual image distance satisfying a corresponding relationship; and controlling the display of the image by adjusting the parallax of the K rows of the image.

[0040] Based on the above scheme, since there is a correspondence between parallax, eye distance and virtual image distance, the parallax corrected in each row can make the virtual image distance of each row of the displayed image the same, thereby achieving the non-tilted (or upright) display of the controlled image.

[0041] In a possible implementation, the corresponding relationship satisfies:

[0042]

[0043] Where ΔP i is the disparity between the first viewpoint and the second viewpoint in the i-th row, T is the distance between the first viewpoint and the second viewpoint, VID is the virtual image distance, ER i is the eye relief of the i-th row.

[0044] In the fifth aspect, the present application provides a chip, which includes at least one processor and an interface circuit. Further, optionally, the chip may also include a memory, and the processor is used to execute computer programs or instructions stored in the memory, so that the chip executes the method in the above-mentioned fourth aspect or any possible implementation of the fourth aspect.

[0045] In the sixth aspect, the present application provides a computer-readable storage medium, which stores a computer program or instructions. When the computer program or instructions are executed by a control device, the control device executes the method in the above-mentioned fourth aspect or any possible implementation of the fourth aspect.

[0046] In the seventh aspect, the present application provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are executed by a control device, the control device executes the method in the above-mentioned fourth aspect or any possible implementation of the fourth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] FIG1a is a schematic diagram of a front windshield of a vehicle to which a display module provided by the present application is applied;

[0048] FIG1b is a schematic diagram of a vehicle window application of a display module provided by the present application;

[0049] FIG1c is a schematic diagram of a display module applied to a skylight provided by the present application;

[0050] FIG1d is a schematic diagram of a display module provided by the present application applied to a NED device;

[0051] FIG1e is a schematic diagram of a display module provided by the present application applied to a vehicle display screen;

[0052] FIG1f is a schematic diagram of a display module provided by the present application applied to a display;

[0053] FIG2 is a schematic structural diagram of a display module provided by the present application;

[0054] FIG3a is a schematic diagram of the relationship between ambient light and image light provided by the present application;

[0055] FIG3 b is another schematic diagram of the relationship between ambient light and image light provided by the present application;

[0056] FIG4 a is a schematic diagram showing the principle of manufacturing a scattering layer by holographic exposure technology provided by the present application;

[0057] FIG4 b is a schematic diagram of the principle of scattering layer reconstruction provided by the present application;

[0058] FIG5a is a schematic structural diagram of a scattering layer provided in the present application;

[0059] FIG5 b is a schematic structural diagram of another scattering layer provided in the present application;

[0060] FIG6 is a schematic structural diagram of a concave cylindrical reflector array provided by the present application;

[0061] FIG7 a is a schematic diagram of a projection of a concave cylindrical reflector array provided by the present application on a first plane;

[0062] FIG7 b is a schematic diagram of a projection of a concave surface on a first plane provided by the present application;

[0063] FIG8 is a schematic diagram of a projection of a concave cylindrical reflector array provided by the present application on a second plane;

[0064] FIG9 shows a correspondence between an array of concave cylindrical reflectors and regions of a scattering layer provided by the present application;

[0065] FIG10 shows the correspondence between another concave cylindrical reflector array and the area of ​​the scattering layer provided by the present application;

[0066] FIG11 is a schematic structural diagram of another concave cylindrical reflector array provided by the present application;

[0067] FIG12a is a schematic diagram of a principle of obtaining a holographic reflective medium layer through a lens array provided by the present application;

[0068] FIG12b is a schematic diagram of a principle of obtaining a holographic reflective medium layer by a reflector array provided by the present application;

[0069] FIG13 is a light path diagram of a display module provided by the present application;

[0070] FIG14 is a schematic diagram of an optical display system architecture provided by the present application;

[0071] FIG15 is a schematic diagram of a method flow of an image display method provided by the present application;

[0072] FIG16a is a schematic diagram showing the positional relationship among the eye relief, virtual image distance, and parallax provided by the present application;

[0073] FIG16b is a schematic diagram of the relationship between parallax and the position of the display module provided by the present application;

[0074] FIG17 is a circuit diagram of an optical display system provided by the present application;

[0075] FIG18 is an exemplary functional block diagram of a vehicle provided in this application. DETAILED DESCRIPTION

[0076] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0077] The following is an explanation of some of the terms used in this application. It should be noted that these explanations are for the purpose of facilitating understanding by those skilled in the art and do not limit the scope of protection claimed in this application.

[0078] 1. Scattering

[0079] Scattering refers to the phenomenon in which a portion of light deviates from its original direction of propagation when passing through a medium. Light that deviates from its original direction is called scattered light.

[0080] 2. Holographic Technology

[0081] The first step in holographic technology is to record the object's light wave information using the principle of interference, which is the filming process. The object being filmed forms a diffuse object beam under laser radiation. Another portion of the laser beam, acting as a reference beam, is directed onto the holographic film, where it overlaps with the object beam, causing interference. Interference refers to the phenomenon in which two or more waves, when meeting in space, superimpose or cancel each other, forming a new waveform. The phase and amplitude of each point on the object's light wave are converted into spatially varying intensities, allowing the contrast and spacing between the interference fringes to record the complete information of the object's light wave. The film recording the interference fringes undergoes processing such as development and fixing to form a holographic layer (or hologram). The second step is to reconstruct the object's light wave information using the principle of diffraction, which is the imaging process.

[0082] 3. Viewpoint

[0083] The viewpoint refers to the location from which the image is observed. Specifically, the viewpoint can be two or more locations within the eyebox. The eyebox generally refers to the area within which the driver's eyes can see the entire displayed image, as shown in Figure 1a below. To accommodate differences in driver height, the eyebox is typically 130mm x 50mm. If the driver's eyes are within the eyebox, they can see a complete and clear image. If the driver's eyes are outside the eyebox, they may experience image distortion, color errors, or even no image at all.

[0084] 4. Virtual Image Distance (VID)

[0085] Virtual image distance is the distance between the viewpoint and the center of the image.

[0086] 5. Parallax

[0087] Parallax refers to the difference in direction when observing the same target from two viewpoints at a certain distance (T).

[0088] The previous text introduced some of the terms involved in this application. The following text introduces the possible application scenarios of this application.

[0089] In one possible application scenario, the display module provided by the present application can be set on the front windshield of the vehicle (with an inclination angle of approximately 30° to 60°) and used in combination with a head-up display device (HUD), see Figure 1a. The HUD can project the formed image (called the HUD virtual image) into the driver's front field of view and integrate it with the real road information, thereby enhancing the driver's perception of the actual driving environment. For example, the HUD can superimpose the HUD virtual image carrying navigation information (such as direction arrows, distance, and / or driving time, etc.) and / or vehicle status information (such as driving speed, mileage, speed, temperature, fuel level, and / or headlight status, etc.) on the real environment outside the vehicle (such as safe vehicle distance, surrounding obstacles, and / or reversing images, etc.), so that the driver can obtain an augmented reality visual effect. Based on this, the vehicle can realize augmented reality (AR) navigation, adaptive cruise control, lane departure warning and other functions. Alternatively, it can be combined with the functions of the advanced driving assistant system (ADAS) to realize assisted driving or intelligent driving of the vehicle. Typically, to avoid interfering with road conditions, the virtual image distance of the HUD formed based on vehicle status information is approximately 2 to 3 meters. To better integrate the HUD virtual image formed based on navigation information with the real road surface, the virtual image distance of the HUD virtual image formed based on navigation information is approximately 7 to 15 meters. HUDs include but are not limited to windshields (W-HUDs) or AR-HUDs.

[0090] In another possible application scenario, the display module provided by this application can also be installed on a vehicle window (such as a side window or rear window) and used in conjunction with an image generation unit. The image generation unit can project image light onto the display module on the vehicle window (see Figure 1b). In this application scenario, the image generation unit can include, but is not limited to, a projector.

[0091] In another possible application scenario, the display module provided by this application can also be set on a skylight and used in conjunction with an image generation unit. The image generation unit can project image light onto the display module of the skylight (see Figure 1c). In this application scenario, the image generation unit can include, but is not limited to, a projector.

[0092] In another possible application scenario, the display module provided by this application can also be integrated into a near-eye display (NED) device. For example, an NED device can be an augmented reality (AR) device or a virtual reality (VR) device. AR devices can include, but are not limited to, AR glasses or AR helmets, and VR devices can include, but are not limited to, VR glasses or VR helmets. Referring to FIG. 1d , using AR glasses as an example, a user can wear AR glasses to play games, watch videos, participate in virtual meetings, or perform video shopping.

[0093] In another possible application scenario, the display module provided by this application can also be integrated into an in-vehicle display screen. Referring to Figure 1e, the in-vehicle display screen can be installed on the back of a vehicle seat or in the passenger seat. This application does not limit the installation location of the in-vehicle display screen. Figure 1e uses the example of installation on the back of a seat as an example.

[0094] In another possible application scenario, the display module provided in the present application can also be integrated into a display as a desktop display, please refer to Figure 1f.

[0095] It should be understood that the possible application scenarios given above are merely examples, and the display module provided in this application can also be applied to other possible display scenarios, and is not limited to the scenarios exemplified above.

[0096] Based on the above content, the present application provides a display module that can achieve 3D transparent display.

[0097] The display module proposed in this application is described in detail below with reference to Figures 2 to 13 .

[0098] As shown in Figure 2, a schematic diagram of the structure of a display module provided by the present application is shown. The display module includes a scattering layer and a reflective layer. The scattering layer is used to receive different image lights from an image generation unit and scatter the different image lights to corresponding positions on the reflective layer. The image lights carry image information, and the image information carried by different image lights can be the same or different, and the polarization states of different image lights can be the same or different. The reflective layer is used to reflect the image lights from corresponding positions on the scattering layer to corresponding viewpoints, as well as to transmit ambient light. For example, the reflective layer is used to reflect the first image light from the scattering layer to a first viewpoint and the second image light to a second viewpoint. It can also be understood that the first image light converges at the first viewpoint and the second image light converges at the second viewpoint. It can be understood that Figure 2 is based on the example of the image generation unit emitting the first image light and the second image light, and takes the example of the first image light converging at the first viewpoint after passing through the scattering layer and the reflective layer, and the second image light converging at the second viewpoint after passing through the scattering layer and the reflective layer.

[0099] Ambient light refers to light other than image light. In one possible implementation, the propagation direction of the ambient light is opposite to that of the image light (see Figure 3a). In another possible implementation, the propagation direction of the ambient light is consistent with that of the image light (see Figure 3b). It should be understood that the ambient light shown in Figures 3a and 3b is merely exemplary, and the propagation direction of the ambient light in this application may also be other possible directions, without limitation.

[0100] Based on the above display module, the scattering layer and the reflective layer cooperate to reflect different image lights to corresponding viewpoints, thereby forming a 3D image. Moreover, because the reflective layer can also transmit ambient light, this display module can achieve 3D transparent display.

[0101] In a possible implementation, the image generating unit may include but is not limited to a projector. To facilitate the description of the solution, the following description takes the image generating unit as an example.

[0102] The following describes each functional structure shown in FIG2 to provide an exemplary specific implementation solution.

[0103] 1. Scattering layer

[0104] In one possible implementation, the scattering layer exhibits angle selectivity, scattering only light incident at a specific angle and remaining transparent to ambient light incident from other directions. Specifically, the scattering layer is configured to scatter image light incident at an angle within a preset angle range. In other words, the image light scattered to a corresponding position on the reflective layer must enter the scattering layer at an angle within the preset angle range.

[0105] The scattering layer can be produced using a holographic exposure method. See Figure 4a. A first laser beam passes through a conventional diffuser (such as frosted glass) and serves as the object beam. A reference laser beam, passing through a semi-transparent mirror, interferes with the object beam on the holographic recording layer. The field of view (or light cone angle) of the reference laser beam is the same as that of the image light emitted by the projector. The angle of incidence of the reference laser beam entering the scattering layer is equal to the angle of incidence of the image light emitted from the projector. The resulting holographic recording layer can then be used as the scattering layer for a display module.

[0106] For example, referring to Figure 4b, the field of view angle of the image light emitted by the projector is ω, and the angle of incidence of the central image light entering the scattering layer is θ. Based on the angle of incidence θ of the central image light entering the scattering layer, the field of view angle ω of the image light, and the angular spacing between adjacent image lights, the angle of incidence of each image light entering the scattering layer can be determined. Based on this, and in conjunction with Figure 4a, when producing the scattering layer using holographic exposure technology, the field of view angle of the reference laser beam is controlled to be ω. By adjusting the semi-transparent and semi-reflective mirrors, the angle of incidence of the central laser beam of the reference laser beam entering the holographic recording layer is θ.

[0107] Holographic exposure is used as a scattering layer. During exposure, the reference laser beam has the same light cone angle and incident angle as the projector. This ensures that only image light with the same light cone angle and incident angle can excite the scattering layer, while ambient light, which does not meet the angle selection conditions, is directly transmitted. Compared with traditional diffusers, this scattering layer has higher transparency.

[0108] It should be noted that the above-mentioned method of producing the scattering layer by holographic exposure is only an example. The scattering layer in this application can also be produced by other possible methods, for example, by doping scattering particles, combining micro-nano structures with phase compensation layers, etc., and this application does not limit this.

[0109] Please refer to Figure 5a, which is a schematic diagram of the structure of a scattering layer provided in this application. This example uses the example of image light from a projector including a first image light and a second image light. The scattering layer includes a first region and a second region. The first region and the second region are divided based on the received image light, as represented by different fills in Figure 5a. The first region is used to scatter the first image light, and the second region is used to scatter the second image light. Specifically, one first image light corresponds to one first region, and one second image light corresponds to one second region.

[0110] Please refer to Figure 5b, which is a schematic diagram of the structure of another scattering layer provided by the present application. In this example, the image light from the projector includes the first image light, the second image light, the third image light and the fourth image light. The scattering layer includes the first area, the second area, the third area and the fourth area as an example. Among them, the first area, the second area, the third area and the fourth area are divided based on the received image light, and are represented by different fillings in Figure 5b. One first image light corresponds to one first area, one second image light corresponds to one second area, one third image light corresponds to one third area, and one fourth image light corresponds to one fourth area. The first area is used to scatter the first image light, the second area is used to scatter the second image light, the third area is used to scatter the third image light, and the fourth area is used to scatter the fourth image light.

[0111] It is understandable that the scattering layer shown in FIGS. 5a and 5b above can be fabricated based on the holographic exposure method shown in FIG. 4a above, or it can also be fabricated by doping scattering particles or micro-nano structures, etc. This application does not limit this. Generally, the sizes of the respective regions included in the scattering layer can be the same.

[0112] II. Reflective layer

[0113] In one possible implementation, the reflective layer is configured to reflect the image light from the corresponding position of the scattering layer to the corresponding viewing point and transmit the ambient light.

[0114] In one possible implementation, the concave cylindrical reflector array can be fabricated by injection molding or nanoimprinting, etc. Two possible structures of the reflective layer are exemplarily shown below.

[0115] Structure 1, the reflective layer includes a concave cylindrical reflector array.

[0116] Based on whether the concave cylindrical reflector array is a one-dimensional array or a two-dimensional array, the following two cases are introduced.

[0117] Case 1, the concave cylindrical reflector array is a one-dimensional concave cylindrical reflector array.

[0118] Please refer to FIG. 6, which is a schematic structural diagram of a concave cylindrical reflector array provided by this application. This concave cylindrical reflector array is a one-dimensional concave cylindrical reflector array. The surface of the concave cylindrical reflector in the concave cylindrical reflector array close to the scattering layer is a concave surface. It should be noted that, without affecting the 3D transparent display, there may be reflectors in the concave cylindrical reflector array that are not concave surfaces. Among them, the projection of the concave surface on the first plane (xoy plane) is an arc. Please refer to FIG. 7a. The sag height or coordinates (x, y) of the arc can be expressed by the following formula 1.

[0119]

[0120] Where c is the curvature, k is the shape coefficient, (when k < -1, the arc is a hyperbola; when k = -1, it is a parabola; when -1 < k < 0, it is an ellipse; when k = 0, it is a circle; when k > 0, it is a flat ellipse).

[0121] Alternatively, the sag height or x coordinate of the arc can be expressed by the following formula 2, that is, a polynomial term can be added based on formula 1:

[0122]

[0123] Where is the polynomial term, A is the coefficient of the polynomial, and N is the order of the polynomial (i.e., the largest power series).

[0124] Based on this, the arc includes, but is not limited to, a parabola, a circular arc, an elliptical arc, a hyperbolic arc, or other possible arcs. For example, the edge of the arc includes a serrated shape (see Figure 7b). It can also be understood that the projection of the concave surface on the first plane can be a regular arc or an irregular arc, which is not limited in this application. For example, the diameter of the arc is generally between 100 microns (μm) and 10 millimeters (mm).

[0125] Furthermore, the concave cylindrical reflectors in this one-dimensional concave cylindrical reflector array are cylindrical structures in a second plane (xoz plane) (e.g., a vertical plane), as shown in Figure 8. The second plane is perpendicular to the first plane, which can be a horizontal plane and a vertical plane. The direction parallel to the first plane is referred to as the first direction, and the direction parallel to the second plane is referred to as the second direction. Based on this one-dimensional concave cylindrical reflector array, the image formed by the image light has parallax and a sense of three-dimensionality in the first direction, but lacks a sense of three-dimensionality in the second direction.

[0126] Specifically, one concave cylindrical reflector in the one-dimensional concave cylindrical reflector array corresponds to at least two columns of regions of the scattering layer. It will be understood that the columns of regions of the scattering layer corresponding to one concave cylindrical reflector are related to the image light emitted by the projector. Referring to FIG. 9 , the projector emits first image light and second image light, and one concave cylindrical reflector corresponds to one column of first regions and one column of second regions of the scattering layer. The scattering layer in this example can be seen in the description of FIG. 4 a above. The first and second regions of the scattering layer are positioned at different locations relative to the concave surface of the concave cylindrical reflector. The first image light passing through the first region of the scattering layer and the second image light passing through the second region of the scattering layer are scattered to corresponding locations on the concave surface of the concave cylindrical reflector. The first image light is reflected to the first viewpoint and the second image light is reflected to the second viewpoint via the corresponding locations on the concave surface of the concave cylindrical reflector.

[0127] Referring to FIG. 10 , a projector emits first, second, third, and fourth image lights. A concave cylindrical reflector corresponds to a first column, a second column, a third column, and a fourth column of regions of a scattering layer. The first, second, third, and fourth regions of the scattering layer are positioned at different locations relative to the concave surface of the concave cylindrical reflector. The first image light passing through the first region of the scattering layer, the second image light passing through the second region of the scattering layer, the third image light passing through the third region of the scattering layer, and the fourth image light passing through the fourth region of the scattering layer are scattered to corresponding locations on the concave surface of the concave cylindrical reflector. The scattering layer in this example can be seen in the description of FIG. 4 b above. The first image light is reflected to the first viewpoint, the second image light to the second viewpoint, the third image light to the third viewpoint, and the fourth image light to the fourth viewpoint from corresponding locations on the concave surface of the concave cylindrical reflector. By arranging a concave cylindrical reflector corresponding to the four columns of regions of the scattering layer, the display module can produce a 3D transparent display with a stronger sense of three-dimensionality.

[0128] In a possible implementation, the following formulas 3 and 4 need to be satisfied between the concave cylindrical reflector array, the scattering layer, and the viewpoint.

[0129]

[0130]

[0131] Where, f represents the focal length of the concave cylindrical reflector, which is equal to the distance from the scattering layer to the concave cylindrical reflector array, and W p represents the length of the first or second region of the scattering layer in the first plane (i.e., the xoy plane), p represents the aperture of the concave cylindrical reflector, L represents the distance from the first viewpoint and the second viewpoint to the display module, and T represents the distance between the first viewpoint and the second viewpoint. It is understood that the first viewpoint and the second viewpoint can be the positions of the left and right eyes of the observer.

[0132] Case 2: the concave cylindrical reflector array is a two-dimensional concave cylindrical reflector array.

[0133] Figure 11 is a schematic diagram of the structure of another concave cylindrical reflector array provided by this application. This concave cylindrical reflector array is a two-dimensional concave cylindrical reflector array. The concave surfaces of the concave cylindrical reflectors in this two-dimensional concave cylindrical reflector array, located near the scattering layer, are projected as an arc on a first plane and also on a second plane. This concave surface can be a parabola, sphere, ellipsoid, hyperboloid, or the like. The sagittal height or x-coordinate of this concave surface can be expressed using the following formula 5.

[0134]

[0135] Among them, c is the curvature and k is the shape coefficient: when k < -1, the arc is a hyperboloid; when k = -1, it is a paraboloid; when -1 < k < 0, it is an ellipsoid; when k = 0, it is a sphere; when k > 0, it is a flattened ellipsoid.

[0136] Alternatively, the sagitta or coordinates (x, y, z) of the concave surface can be expressed by the following formula 6. That is, polynomial terms may be added on the basis of formula 5:

[0137]

[0138] Among them, is a polynomial, A is the coefficient of the polynomial, and N is the order of the polynomial (i.e., the largest power series).

[0139] Based on this, the concave surface can be, for example, a spherical surface, an ellipsoidal surface, a hyperboloidal surface, or other possible surface types, which are not limited in this application.

[0140] Through the above two-dimensional concave cylindrical reflector array, the image formed by the image light has parallax and stereoscopic sense in the first direction and also has parallax and stereoscopic sense in the second direction.

[0141] In a possible implementation, the concave surface of the concave cylindrical reflector in the concave cylindrical reflector array is covered with a reflective film, and the reflectivity of the reflective film is greater than the first reflectivity threshold and less than the second reflectivity threshold, so that the reflective film can both reflect the image light from the scattering layer and transmit the ambient light, thereby realizing 3D transparent display. It can also be understood that the reflective film is a reflective film that partially reflects and partially transmits. Exemplarily, the reflective film may include, but is not limited to, a nano metal film or a dielectric film, and the nano metal film or the dielectric film can achieve partial reflection and partial transmission. For example, the reflectivity of the reflective film is greater than 0 and less than 100%.

[0142] Furthermore, optionally, the reflectivity of the reflective film is related to the requirements of the transmittance of the reflective film. When the display module is applied to different scenarios, there are certain requirements for the transmittance of the reflective film. For example, when the display module is set on the windshield, the transmittance of the windshield needs to be greater than 70%. Therefore, the transmittance of the reflective film needs to be greater than 70%. Also, since the sum of the reflectivity and the transmittance of the reflective film is equal to 100%, the reflectivity of the reflective film is less than 30% and greater than 0. It can also be understood that the reflective film needs to satisfy both transmitting the ambient light and reflecting the received image light. In other words, the first reflectivity threshold of the reflective film needs to satisfy that the reflected image light can achieve 3D image display, and the second reflectivity threshold of the reflective film needs to satisfy that the transmitted ambient light can meet the application scenario of the display module. Exemplarily, the reflectivity of the reflective film can be set between 10% and 30%, that is, the first reflectivity threshold is equal to 10% and the second reflectivity threshold is equal to 30%. Based on this reflective film, the display module can achieve 3D transparent display.

[0143] To ensure that the propagation direction of ambient light is not affected, the concave surface of the concave cylindrical reflector is filled with a filler. The refractive index of the filler and the refractive index of the concave cylindrical reflector meet a predetermined tolerance. Furthermore, the refractive index of the filler is the same as that of the concave cylindrical reflector. The material of the filler and the material of the concave cylindrical reflector may be the same or different, and this application does not impose any restrictions. It is understood that due to the relatively small thickness of the reflective film, the effect of the reflective film on the propagation direction of ambient light is negligible.

[0144] The concave cylindrical reflector array based on the above-mentioned structure 1 is used as a reflective layer. There is no need for a traditional transmissive cylindrical lens array. The display module can be made transparent to ambient light by directly using a concave cylindrical reflector array covered with a reflective surface and filled with a filling layer on the concave surface, thereby realizing 3D transparent display.

[0145] Structure 2: The reflective layer includes a holographic reflective medium layer.

[0146] In one possible implementation, the holographic reflective layer exhibits angular selectivity. Only image light scattered by the scattering layer that enters the holographic reflective layer from the front can excite the layer. That is, only image light entering the holographic reflective layer from the front can be reflected (or diffracted) by the holographic reflective layer to the corresponding viewpoint. The vast majority of ambient light passes directly through the holographic reflective layer.

[0147] The holographic reflective medium layer can be produced by holographic exposure. Two implementation methods of producing the holographic reflective medium layer by holographic exposure are shown below.

[0148] Implementation method 1: using a lens array to prepare a holographic reflective medium layer through holographic exposure.

[0149] Referring to Figure 12a, a second laser beam is incident perpendicularly on the holographic reflective dielectric layer from one side, while a third laser beam is incident on the lens array from the other side. After being diffused by the lens array, it enters the holographic reflective dielectric layer. The dimensions of the lenses in the lens array are identical to those of the concave cylindrical reflectors in the display module's concave cylindrical reflector array, and the focal lengths of the lenses in the lens array are identical to those of the concave cylindrical reflectors in the display module's concave cylindrical reflector array. This creates a holographic reflective dielectric layer, where image light scattered by the scattering layer excites the holographic reflective dielectric layer, while the vast majority of ambient light passes directly through.

[0150] In one possible implementation, the lens array may be a cylindrical lens array. The cylindrical lens array may be arranged one-dimensionally, which can produce parallax and stereoscopic vision in a first direction. Alternatively, the cylindrical lens array may be arranged two-dimensionally, which can produce parallax and stereoscopic vision in both the first and second directions.

[0151] Implementation method 2: using a reflector array to prepare a holographic reflective medium layer through holographic exposure.

[0152] Referring to Figure 12b, a fourth laser beam perpendicularly enters the holographic reflective medium layer from one side, passes through the concave reflector array, and is reflected by the concave reflector array before reentering the holographic reflective medium layer. The dimensions of the concave reflectors in the concave reflector array are identical to those of the concave cylindrical reflectors in the display module's concave cylindrical reflector array, and their focal lengths are identical to those of the concave cylindrical reflectors in the display module's concave cylindrical reflector array. This results in a holographic reflective medium layer. Image light scattered by the scattering layer excites the holographic reflective medium layer, while the vast majority of ambient light passes directly through.

[0153] The concave reflector array may be a concave cylindrical reflector array. The arrangement of the cylindrical concave reflector array can refer to the arrangement of the cylindrical lens, which will not be described in detail here.

[0154] Based on the above-mentioned implementation method 2, the holographic reflective medium layer is prepared using the third laser beam, which has low requirements for environmental vibration and low exposure costs. Moreover, the holographic reflective medium layer prepared by holographic exposure is relatively thin (e.g., less than 100 μm), which facilitates the thinning of the display module.

[0155] The holographic reflective medium layer produced by Implementation Method 1 or Implementation Method 2 above has a volume grating structure with strong angular selectivity. Using this holographic reflective medium layer as a reflective layer, the optical path of the display module is reconstructed as shown in Figure 13. Image light emitted from the projector is scattered by the scattering layer into the holographic reflective medium layer, thereby exciting the holographic reflective medium layer. The holographic reflective medium layer then reflects the first image light to the first viewpoint and the second image light to the second viewpoint. Most of the ambient light passes directly through the holographic reflective medium layer.

[0156] Based on the structure and functional principle of the display module described above, the present application also provides an optical display system. Please refer to Figure 14. The optical display system includes an image generating unit and a display module in any of the above embodiments. The image generating unit is used to emit different image lights. In this example, the image generating unit emitting the first image light and the second image light is taken as an example. The scattering layer included in the display module is taken as an example in Figure 5a above, and the reflective layer included in the display module is taken as an example in Figure 6 above. For details, please refer to the above-mentioned related introduction, which will not be repeated here. The first image light emitted by the image generating unit converges at a first viewpoint through the display module, and the second image light emitted by the image generating unit converges at a second viewpoint through the display module. The ambient light can pass through the display module, thereby realizing 3D transparent display.

[0157] In one possible implementation, the image generation unit includes a light source assembly and a light modulation assembly. The light source assembly is configured to emit a first light beam and a second light beam. The light modulation assembly is configured to modulate the first light beam to obtain a first image light beam carrying the first image information, and to modulate the second light beam to obtain a second image light beam carrying the second image information. Specifically, the light modulation assembly may load (or modulate) the first image information onto the first light beam to obtain the first image light beam carrying the image information; and load the second image information onto the second light beam to obtain the second image light beam carrying the image information. The first and second light beams may be referred to as optical carriers.

[0158] Exemplarily, the light source assembly may be, for example, a laser diode (LD), a light-emitting diode (LED), a vertical cavity surface emitting laser (VCSEL), an edge emitting laser (EEL), a diode pumped solid state laser (DPSS), or a fiber laser. It will be understood that the light source assembly given above is merely an example and is not limited in this application. The light modulation component may be, for example, a liquid crystal on silicon (LCOS) display, a liquid crystal display (LCD), a digital light processing (DLP) display, a laser beam scanning (LBS) display, an organic light emitting diode (OLED), a micro light emitting diode (micro-LED), an active-matrix organic light emitting diode or an active-matrix organic light emitting diode (AMOLED), a flexible light-emitting diode (FLED), a quantum dot light emitting diode (QLED), a reflective display based on a digital micro-mirror device (DMD), etc. It should be noted that the light modulation components given above are only examples and are not limited to them in this application. Other components that can modulate image information of the first light beam and the second light beam are also within the scope of protection of this application.

[0159] Exemplarily, the image generating unit may be a projector, for example.

[0160] Based on the above content and the same concept, the present application provides an image display method, as described in Figure 15 . This image display method can be applied to the display module shown in any of the embodiments shown in Figures 2 to 13 , or to the optical display system shown in Figure 14 . It can also be understood that the image display method can be implemented based on the display module shown in any of the embodiments shown in Figures 2 to 13 , or the image display method can be implemented based on the optical display system shown in Figure 14 .

[0161] As shown in FIG15 , an image display method provided by the present application includes the following steps:

[0162] Step 1501: Obtain the coordinates of the first viewpoint and / or the second viewpoint.

[0163] For example, the coordinates of the first viewpoint are (x1, y1), and the coordinates of the second viewpoint are (x2, y2). Exemplarily, the left and right eyes of the observer may be located at the first viewpoint and the second viewpoint.

[0164] In a possible implementation, the coordinates of the first viewpoint and the coordinates of the second viewpoint may be default eye point coordinates.

[0165] In another possible implementation, the first viewpoint and the second viewpoint may be the positions of the observer's eyes, and the position coordinates of the eyes may be obtained by an eye tracker. Eye tracking refers to tracking eye movement by measuring the position of the eye's gaze point or the movement of the eye relative to the head. An eye tracker is a device that can track and measure eye position and eye movement information. The eye tracker can track and output the position coordinates of the observer's eyes in real time. Exemplarily, the eye tracker may include, but is not limited to, a camera (such as a driver monitor system (DMS) camera), an infrared transmitter or an infrared detector, etc.

[0166] Step 1502 : Determine K eye reliefs based on the coordinates of the first viewpoint and / or the second viewpoint and the coordinates of K target positions in the display area of ​​the windshield.

[0167] Among them, the K target positions correspond one-to-one to the K rows of the image projected onto the display area. In other words, one row of the image projected onto the display area can correspond to one target position on the windshield. Please refer to Figure 16a. Taking the three target positions on the windshield (target position 1, target position 2, and target position 3) as an example, the coordinates of the three target positions are: the coordinates of target position 1 (X1, Y1, Z1), the coordinates of target position 2 (X2, Y2, Z2), and the coordinates of target position 3 (X3, Y3, Z3). These three target positions correspond to three different rows of the image. It can be understood that the coordinates of the target positions in the display area of ​​the windshield can be pre-stored.

[0168] The eye relief refers to the distance between the first viewpoint (or the second viewpoint) and the target position of the display area of ​​the windshield. i The following formula 7 is satisfied. It can be understood that the ER of the same plane is the same, as shown in Figure 16b. Therefore, the ER is the same for the observer's left and right eyes.

[0169]

[0170] It can be understood that if the above step 1501 obtains the coordinates of the first viewpoint, the above formula 7 can use the coordinates of the first viewpoint; if the above step 1501 obtains the coordinates of the second viewpoint, the above formula 7 can use the coordinates of the second viewpoint; if the above step 1501 obtains the coordinates of the first viewpoint and the second viewpoint, the above formula 7 can use the average value of the coordinates of the first viewpoint and the second viewpoint.

[0171] Based on the above formula 7, the eye distance ER1, the eye distance ER2 and the eye distance ER3 can be determined.

[0172] In a possible implementation, the parallax, eye relief, and virtual image distance between the first viewpoint and the second viewpoint satisfy the following formula 8.

[0173]

[0174] Where ΔP i is the disparity between the first viewpoint and the second viewpoint in the i-th row, VID is the virtual image distance, ER i is the eye relief of the i-th row, and T is the distance between the first and second viewpoints. If the first and second viewpoints are the left and right eyes of the observer, T is the distance between the observer's eyes, which is usually about 65 mm.

[0175] Step 1503: Control the display of the image by adjusting the parallax of K lines of the image.

[0176] Since the windshield is tilted, the image seen by the observer is also tilted. In order to observe a non-tilted image, the virtual image distance VID corresponding to each row needs to be the same. Based on the above formula 8, the parallax ΔP1 between the first viewpoint and the second viewpoint in the first row, the parallax ΔP2 between the first viewpoint and the second viewpoint in the second row, and the parallax ΔP3 between the first viewpoint and the second viewpoint in the third row can be determined. Please refer to Figure 16a. Therefore, the parallax ΔP of each row can be adjusted. i , to observe the non-tilted image.

[0177] Based on the above steps 1501 to 1503, by adjusting the parallax of each row, a non-tilted image can be displayed. In other words, based on the above method, a tilted 3D image caused by a tilted windshield can be corrected.

[0178] In a possible implementation, if the user needs to adjust the imaging position, he can first input the target VID, and adjust the parallax ΔP according to the above formula 8 and the target VID. i To realize the image display at the imaging position required by the user. It can be understood that if the parallax ΔP is increased i , the imaging distance will be extended (i.e., the virtual image distance will be increased); if the parallax ΔP is reduced i , the imaging distance will be reduced (that is, the virtual image distance will be reduced).

[0179] The image display method can be executed by a control module, which can belong to the optical display system or can be independent of the optical display. Exemplarily, the control module can include a processor, which can be a circuit with signal (or data) processing capabilities. In one implementation, the processor can be a circuit with instruction reading and execution capabilities, such as a central processing unit (CPU), a microprocessor, a graphics processing unit (GPU) (which can be understood as a microprocessor), or a digital signal processor (DSP); in another implementation, the processor can implement certain functions through the logical relationship of a hardware circuit, and the logical relationship of the hardware circuit is fixed or reconfigurable, such as a hardware circuit implemented by a processor as an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as a field programmable gate array (FPGA). In a reconfigurable hardware circuit, the process of the processor loading a configuration document to implement the hardware circuit configuration can be understood as the process of the processor loading instructions to implement the functions of some or all of the above units. In addition, the processor can also be a hardware circuit designed for artificial intelligence, which can be understood as an ASIC, such as a neural network processing unit (NPU), a tensor processing unit (TPU), a deep learning processing unit (DPU), etc. For example, it can also be an application processor (AP), an image signal processor (ISP), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof.

[0180] When the optical display system belongs to a vehicle, the control module may be a domain processor in the vehicle, or may be an electronic control unit (ECU) in the vehicle.

[0181] Based on the above content, Figure 17 is a circuit diagram of an optical display system provided by the present application. The circuit in the optical display system mainly includes a processor 1701, an external memory interface 1702, an internal memory 1703, an audio module 1704, a video module 1705, a power module 1706, a wireless communication module 1707, an input / output (I / O) interface 1708, a video interface 1709, a display circuit 1710, a modulator 1711 and a light source 1712. Among them, the processor 1701 and its peripheral components, such as the external memory interface 1702, the internal memory 1703, the audio module 1704, the video module 1705, the power module 1706, the wireless communication module 1707, the I / O interface 1708, the video interface 1709, and the display circuit 1710 can be connected via a bus.

[0182] It should be noted that the circuit diagrams shown in this application do not constitute a specific limitation on the optical display system. In other embodiments of this application, the optical display system may include more or fewer components than shown, or may combine or separate certain components, or have different component arrangements. The components shown in the diagrams may be implemented in hardware, software, or a combination of software and hardware.

[0183] The processor 1701 includes one or more processing units. A processing unit may be a circuit having signal (or data) processing capabilities. For details, please refer to the aforementioned related introduction and will not be repeated here. Different processing units may be independent devices or integrated into one or more processors.

[0184] Processor 1701 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 1701 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 1701. If processor 1701 needs to use the same instruction or data again, it can directly retrieve it from the memory. This avoids repeated accesses, reduces processor 1701's waiting time, and thus improves the efficiency of the optical display system. Processor 1701 can execute the stored instructions to perform the aforementioned imaging method.

[0185] In some embodiments, the optical display system may further include a plurality of input / output (I / O) interfaces 1708 connected to the processor 1701. The I / O interfaces 1708 may include 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. The I / O interfaces 1708 may be connected to devices such as a mouse, a touchpad, a keyboard, a camera, a speaker, a microphone, and may also be connected to physical buttons on the optical display system (e.g., a volume button, a brightness adjustment button, a power button, etc.).

[0186] The external memory interface 1702 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the optical display system. The external memory card communicates with the processor 1701 through the external memory interface 1702 to implement data storage.

[0187] The internal memory 1703 can be used to store computer executable program code, which includes instructions. The internal memory 1703 may include a program storage area and a data storage area. The program storage area may store an operating system, at least one application required for a function, and the like. The data storage area may store data created during the use of the optical display system, and the like. In addition, the internal memory 1703 may include random access memory (RAM), flash memory, universal flash storage (UFS), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. The processor 1701 executes various functional applications and data processing of the optical display system by running instructions stored in the internal memory 1703 and / or instructions stored in a memory provided in the processor 1701. In one exemplary embodiment, a storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. In another example, the storage medium may be an integral part of the processor. The processor and storage medium may be located in an ASIC. Alternatively, the ASIC may be located in the optical display system. Of course, the processor and storage medium may also be present as discrete components in the optical display system.

[0188] The optical display system can implement audio functions such as music playback and calls through the audio module 1704 and the application processor.

[0189] The audio module 1704 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 1704 can also be used to encode and decode audio signals, such as for playing or recording. In some embodiments, the audio module 1704 can be provided in the processor 1701, or some functional modules of the audio module 1704 can be provided in the processor 1701.

[0190] The video interface 1709 can receive external audio and video signals, which can specifically be a high-definition multimedia interface (HDMI), a digital visual interface (DVI), a video graphics array (VGA), a display port (DP), etc. The video interface 1709 can also output video to the outside. When the optical display system is used as a head-up display, the video interface 1709 can receive speed signals and power signals input from peripheral devices, and can also receive external AR video signals. When the optical display system includes a projector, the video interface 1709 can receive video signals input from an external computer or terminal device.

[0191] The video module 1705 can decode the video input by the video interface 1709, for example, by performing H.264 decoding. The video module can also encode the video captured by the optical display system, for example, by performing H.264 encoding on the video captured by an external camera. In addition, the processor 1701 can also decode the video input by the video interface 1709 and output the decoded image signal to the display circuit 1710.

[0192] The power module 1706 is configured to provide power to the processor 1701 and the light source 1712 based on input power (e.g., direct current). The power module 1706 may include a rechargeable battery that provides power to the processor 1701 and the light source 1712. Light emitted by the light source 1712 may be transmitted to the modulator 1711 for imaging, thereby forming an image light signal.

[0193] The wireless communication module 1707 enables the optical display system to communicate wirelessly with the outside world. It 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 technology (IR) and other wireless communication solutions. The wireless communication module 1707 can be one or more devices that integrate at least one communication processing module. The wireless communication module 1707 receives electromagnetic waves via an antenna, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 1701. The wireless communication module 1707 can also receive the signal to be sent from the processor 1701, frequency modulate it, amplify it, and convert it into electromagnetic waves for radiation through the antenna.

[0194] In addition, in addition to being input through the video interface 1709, the video data decoded by the video module 1705 can also be received wirelessly through the wireless communication module 1707 or read from an external memory. For example, the optical display system can receive video data from a terminal device or an in-vehicle entertainment system through the wireless LAN in the vehicle, and the optical display system can also read audio and video data stored in an external memory.

[0195] The display circuit 1710 and modulator 1711 are used to display corresponding images. In this embodiment, the video interface 1709 receives an external video source signal, which the video module 1705 decodes and / or digitizes before outputting one or more image signals to the display circuit 1710. The display circuit 1710 drives the modulator 1711 based on the input image signal to image the incident polarized light, thereby outputting at least two image lights. Furthermore, the processor 1701 may also output one or more image signals to the display circuit 1710.

[0196] Exemplarily, the optical display system may include but is not limited to a system formed by a HUD and a windshield, a display, a vehicle-mounted display screen, an AR device, or a VR device, etc., wherein the AR device may include but is not limited to AR glasses or an AR helmet, etc., and the VR device may include but is not limited to VR glasses or a VR helmet, etc.

[0197] Based on the structure and functional principle of the optical display system described above, the present application can also provide a terminal device. The terminal device may include the optical display system in any of the above embodiments. Exemplarily, the terminal device can be, for example, a vehicle (such as an unmanned vehicle, a smart car, an electric car, or a digital car), a robot, a surveying and mapping equipment, a drone, a smart home device (such as a TV, a sweeping robot, a smart desk lamp, a sound system, a smart lighting system, an electrical control system, a home background music, a home theater system, an intercom system, or a video surveillance system), an intelligent manufacturing device (such as an industrial device), an intelligent transportation device (such as an AGV, an unmanned transport vehicle, or a truck), or an intelligent terminal (a mobile phone, a computer, a tablet computer, a PDA, a desktop computer, a headset, an audio system, a wearable device, an on-board device, a virtual reality device, an augmented reality device, etc.), etc.

[0198] Taking the terminal device as a vehicle as an example, please refer to Figure 18, which is an exemplary functional block diagram of a vehicle provided by this application. Components coupled to or included in the terminal device 1800 may include a propulsion system 1801, a sensing system 1802, a control system 1803, a computer system 1804, a user interface 1805, and an optical display system 1806. The components of the terminal device 1800 can be configured to operate in a manner that is interconnected with each other and / or with other components coupled to each system. For example, the computer system 1804 can be configured to receive data from the propulsion system 1801, the sensing system 1802, and the control system 1803 and control them. The computer system 1804 can also be configured to generate an image display on the user interface 1805 and receive input from the user interface 1805.

[0199] The propulsion system 1801 can provide power for the terminal device 1800. The propulsion system 1801 may include an engine, an energy source, a transmission, and wheels / tires. In addition, the propulsion system 1801 may additionally or alternatively include other components besides those shown in FIG. 18 . This application does not specifically limit this.

[0200] Sensing system 1802 may include several sensors for sensing information about the environment in which terminal device 1800 is located. For example, sensors in sensing system 1802 may include, but are not limited to, a global positioning system (GPS), an inertial measurement unit (IMU), millimeter-wave radar, lidar, a camera, and actuators for modifying the position and / or orientation of the sensors. Millimeter-wave radar utilizes radio signals to sense objects within the environment surrounding terminal device 1800. In some embodiments, in addition to sensing objects, millimeter-wave radar may also be used to sense the speed and / or heading of an object. Lidar may utilize lasers to sense objects within the environment in which terminal device 1800 is located. In some embodiments, the lidar may include one or more laser sources and one or more detectors, among other system components. A camera may be used to capture multiple images of the environment surrounding terminal device 1800. The camera may be a still camera or a video camera. In some embodiments, GPS may be any sensor used to estimate the geographic location of terminal device 1800. To this end, the GPS may include a transceiver that estimates the position of terminal device 1800 relative to the Earth based on satellite positioning data. In some possible examples, the computer system 1804 can be configured to use GPS in conjunction with map data to estimate the road traveled by the terminal device 1800. The IMU can be configured to sense changes in the position and orientation of the terminal device 1800 based on inertial acceleration and any combination thereof. In some examples, the combination of sensors in the IMU can include, for example, an accelerometer and a gyroscope. Other combinations of sensors in the IMU are also possible.

[0201] It is understood that the sensing system 1802 may also include sensors of the internal systems of the monitored terminal device 1800 (e.g., an in-vehicle air quality monitor, a fuel gauge, an oil temperature gauge, etc.). Sensor data from one or more of these sensors can be used to detect objects and their corresponding characteristics (position, shape, direction, speed, etc.). This detection and identification is a key function for the safe operation of the terminal device 1800. The sensing system 1802 may also include other sensors. This application does not specifically limit this.

[0202] Control system 1803 controls the operation of terminal device 1800 and its components. Control system 1803 may include various components, including a steering unit, a throttle, a brake unit, a sensor fusion algorithm, a computer vision system, a route control system, and an obstacle avoidance system. The steering system is operable to adjust the direction of travel of terminal device 1800. For example, in one embodiment, it may be a steering wheel system. The throttle is used to control the engine speed and, in turn, the speed of terminal device 1800. Control system 1803 may additionally or alternatively include other components beyond those shown in FIG. 18 . This application is not limited in this regard. The brake unit is used to control the deceleration of terminal device 1800. The brake unit may use friction to slow the wheels. In other embodiments, the brake unit may convert the kinetic energy of the wheels into electrical current. The brake unit may also take other forms to slow the wheel speed and thus control the speed of terminal device 1800. The computer vision system is operable to process and analyze images captured by the camera to identify objects and / or features in the environment surrounding terminal device 1800. Objects and / or features may include traffic signs, road boundaries, and obstacles. The computer vision system can use target recognition algorithms, structure from motion (SFM) algorithms, video tracking and other computer vision technologies. In some embodiments, the computer vision system can be used to map the environment, track targets, estimate the speed of targets, and the like. The route control system is used to determine the driving route of the terminal device 1800. In some embodiments, the route control system can combine data from the sensing system 1802, GPS, and one or more predetermined maps to determine the driving route for the terminal device 1800. The obstacle avoidance system is used to identify, evaluate, and avoid or otherwise overcome potential obstacles in the environment of the terminal device 1800. Of course, in one embodiment, the control system 1803 can include components other than those shown and described in addition or in an alternative manner. Alternatively, some of the components shown above can be reduced.

[0203] Some or all functions of terminal device 1800 are controlled by computer system 1804. Computer system 1804 may include at least one processor 18041 and may further include interface circuitry 18042. Processor 18041 executes instructions stored in a non-transitory computer-readable medium, such as memory 18043. Computer system 1804 may also be a plurality of computing devices that control individual components or subsystems of terminal device 1800 in a distributed manner.

[0204] The processor 18041 may be a circuit having the capability of processing signals (or data). For details, please refer to the above-mentioned related introduction, which will not be repeated here.

[0205] Although FIG18 functionally illustrates the processor, memory, and other elements of computer system 1804 in the same block, it will be understood by those skilled in the art that the processor and memory may not actually be stored in the same physical housing as multiple processors or memories. For example, the memory may be a hard drive or other storage medium located in a different housing than computer system 1804. Rather than using a single processor to perform the steps described herein, some components, such as the steering assembly and the deceleration assembly, may each have their own processor that performs only calculations related to the functions of the component. For another example, the processor may be remote from the vehicle but may be in wireless communication with the vehicle.

[0206] In some embodiments, memory 18043 may include instructions (e.g., program logic) that can be read by processor 18041 to perform various functions of terminal device 1800, including the functions described above. Memory 18043 may also include additional instructions, including instructions for sending data to, receiving data from, interacting with, and / or controlling one or more of propulsion system 1801, sensing system 1802, and control system 1803. In addition to instructions, memory 18043 may also store data such as road maps, route information, data detected by sensors, the vehicle's location, direction, speed, and other such vehicle data, as well as other information. This information can be used by terminal device 1800 and computer system 1804 when the terminal device 1800 is in autonomous, semi-autonomous, and / or manual mode.

[0207] For the memory, please refer to the introduction of the internal memory 1703 in Figure 17 above, which will not be repeated here.

[0208] The user interface 1805 is used to provide information to or receive information from a user of the terminal device 1800. Optionally, the user interface 1805 may include one or more input / output devices within a collection of peripheral devices, such as a wireless communication system, a touch screen, a microphone, and / or a speaker.

[0209] Computer system 1804 can control the functions of terminal device 1800 based on input received from various subsystems (e.g., propulsion system 1801, sensing system 1802, and control system 1803) and from user interface 1805. For example, computer system 1804 can use input from control system 1803 to control the steering unit to avoid obstacles detected by sensing system 1802 and obstacle avoidance system. In some embodiments, computer system 1804 is operable to provide control over many aspects of terminal device 1800 and its subsystems.

[0210] The optical display system 1806 can be described in any of the above embodiments and will not be described in detail here. It should be noted that the functions of some components in the optical display system can also be implemented by other subsystems of the vehicle. For example, the controller can also be a component in the control system.

[0211] Optionally, one or more of the above components may be installed or associated separately from the terminal device 1800. For example, the memory 18043 may be partially or completely separate from the terminal device 1800. The above components may be communicatively coupled together in a wired and / or wireless manner.

[0212] It should be noted that the terminal device functional framework shown in FIG18 is merely an example. In other examples, the terminal device 1800 may include more, fewer, or different systems, and each system may include more, fewer, or different components. Furthermore, the systems and components shown may be combined or divided in any manner, and this application does not impose any specific limitations thereon.

[0213] The method steps in the embodiments of the application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, which can be stored in a storage medium. For details about the storage medium, please refer to the introduction of the aforementioned memory 18043 and will not be repeated here. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor.

[0214] In the above embodiments, they can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, they can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are performed in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, a hard disk, or a tape; it can also be an optical medium, such as a digital video disc (DVD); it can also be a semiconductor medium, such as a solid-state drive (SSD).

[0215] In the various embodiments of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0216] In this application, "uniform" does not mean absolute uniformity, and a certain engineering error can be allowed. "Vertical" does not mean absolute verticality, and a certain engineering error can be allowed. "At least one" means one or more, and "multiple" means two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple. In the text description of this application, the character " / " generally indicates that the related objects before and after are in an "or" relationship. In the formula of this application, the character " / " indicates that the related objects before and after are in a "division" relationship. Additionally, in this application, the word "exemplary" is used to mean an example, illustration, or description. Any embodiment or design described in this application as an "exemplary" should not be construed as preferred or advantageous over other embodiments or designs. Alternatively, it can be understood that the use of the word "exemplary" is intended to present concepts in a concrete manner and does not constitute a limitation of this application.

[0217] It will be appreciated that the various numerical numbers involved in this application are merely for the purpose of describing the distinctions made, and are not intended to limit the scope of the embodiments of the present application. The size of the sequence numbers of the above-mentioned processes does not imply the order of execution, and the order of execution of each process should be determined by its function and inherent logic. Terms such as "first", "second", and similar expressions are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, comprising a series of steps or units. Methods, systems, products, or devices are not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or that are inherent to these processes, methods, products, or devices.

[0218] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A display module, characterized in that: including a scattering layer and a reflecting layer; The scattering layer is used to receive different image lights from the image generating unit and scatter the different image lights to corresponding positions of the reflective layer, wherein the image lights carry image information; The reflective layer is used to reflect the image light from the corresponding position of the scattering layer to the corresponding viewpoint and transmit the ambient light.

2. The module according to claim 1, wherein: The reflective layer comprises an array of concave cylindrical reflective elements, wherein the surfaces of the concave cylindrical reflective elements in the array of concave cylindrical reflective elements close to the scattering layer are concave surfaces, and the concave surfaces are covered with a reflective film.

3. The module according to claim 2, wherein: The projection of the concave surface close to the scattering layer on at least the first plane is an arc.

4. The module according to claim 2 or 3, wherein: The reflectivity of the reflective film is greater than a first reflectivity threshold and less than a second reflectivity threshold.

5. The module according to claim 4, wherein: The reflectivity of the reflective film is related to the transmittance requirement of the reflective film.

6. The module according to any one of claims 2 to 5, wherein: The reflective film includes a nano-metal film or a dielectric film.

7. The module according to any one of claims 2 to 6, wherein: The concave surface is filled with a filler, and the refractive index of the filler and the refractive index of the concave cylindrical reflector meet a preset error requirement.

8. The module according to claim 7, wherein: The refractive index of the filler is the same as the refractive index of the concave cylindrical reflector.

9. The module according to any one of claims 2 to 8, wherein: The concave cylindrical reflector array is a one-dimensional array, one concave cylindrical reflector in the concave cylindrical reflector array corresponds to N columns of regions of the scattering layer, the N columns of regions are used to receive different image lights, and N is an integer greater than 1.

10. The module according to any one of claims 2 to 8, wherein: The concave cylindrical reflector array is a two-dimensional array, and one concave cylindrical reflector in the concave cylindrical reflector array corresponds to one area of ​​the scattering layer.

11. The module according to claim 1, wherein: The reflective layer includes a holographic reflective medium layer.

12. The module according to any one of claims 1 to 11, wherein: The incident angle of the image light scattered to the corresponding position of the reflective layer entering the scattering layer belongs to a preset angle range.

13. The module according to any one of claims 1 to 12, wherein: The scattering layer is obtained by holographic exposure.

14. An optical display system, characterized in that: comprising an image generating unit and a display module according to any one of claims 1 to 13; The image generating unit is used to emit different image lights.

15. The system according to claim 14, wherein: The polarization states of the different image lights are the same.

16. The system according to claim 14 or 15, characterized in that The image generating unit includes a projector.

17. A terminal device, characterized in that: The optical display system comprises the optical display system according to any one of claims 14 to 16, wherein the optical display system is installed on the terminal device.

18. An image display method, characterized in that: include: Obtaining coordinates of the first viewpoint and / or the second viewpoint; determining K eye reliefs based on the coordinates of the first viewpoint and / or the second viewpoint and the coordinates of K target positions in the display area of ​​the windshield, wherein the K target positions correspond one-to-one to K rows of the image projected onto the display area, and the parallax, eye relief, and virtual image distance between the first viewpoint and the second viewpoint satisfy a corresponding relationship; The display of the image is controlled by adjusting the parallax of K lines of the image.

19. The method according to claim 18, wherein The corresponding relationship satisfies: Wherein, the ΔP i is the disparity between the first viewpoint and the second viewpoint in the i-th row, T is the distance between the first viewpoint and the second viewpoint, VID is the virtual image distance, and ER i is the eye relief of the i-th row.

20. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program or instruction. When the computer program or instruction is executed by the control device, the control device executes the method according to any one of claims 18 to 19.

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