Multiplexed floating autostereoscopic 3D display

Abstract

A multi-view bonfire display includes a light source configured to emit a light beam and a spatial light modulator (SLM) positioned to receive the light beam emitted by the light source. The holographic display also includes a user tracker configured to track a head and eyes of an occupant on the vehicle. The display also includes a controller in communication with the user tracker, the light source, and the SLM. The controller is programmed to receive the eye tracking signal from the user tracker and to control polarized optical characteristics of the light beam emitted by the light source and modulated by the SLM to re-route the images encoded by the SLM for the plurality of on-board occupants based on the eye tracking signal such that each of the plurality of on-board occupants can see the images.

Description

Technical Field

[0001] The present disclosure relates to displays, and more particularly to multiplexed floating autostereoscopic displays. Background Art

[0002] This introduction generally presents the background of the present disclosure. To the extent described in this introduction, the work of the presently named inventors and aspects of the description that may not constitute prior art at the time of filing are neither explicitly nor implicitly admitted to be prior art to the present disclosure.

[0003] In a vehicle equipped with campfire seats, it would be desirable to display a hologram that is visible to all passengers. In this case, the display should be able to display the hologram to multiple vehicle occupants sitting around using as little hardware as possible. Summary of the invention

[0004] The present disclosure describes a multiplexed floating free stereoscopic display. According to one aspect of the present disclosure, the multi-view campfire display (Campfire Display) includes a light source configured to emit a light beam and a spatial light modulator (SLM) positioned to receive the light beam emitted by the light source. The spatial light modulator (SLM) is configured to encode an image. The holographic display also includes a user tracker (e.g., an eye tracker) configured to track the head and eyes of the occupants on the vehicle. The user tracker is configured to generate an eye tracking signal. The eye tracking signal indicates the position of the eyes of each of the multiple occupants on the vehicle. The display also includes a controller that communicates with the user tracker, the light source, and the SLM. The controller is programmed to receive the eye tracking signal from the user tracker, and control the polarization optical properties of the light beam emitted by the light source and modulated by the SLM, so as to reroute the image encoded by the SLM for multiple occupants on the vehicle based on the eye tracking signal, so that each of the multiple occupants on the vehicle can see the image. The image is rerouted to multiple users using one of the following three technologies (e.g., SLM grating, digital micromirror device (DMD) or liquid crystal (LC) polarization rotator). The SLM and rerouting devices (e.g., SLM gratings, digital micromirror devices (DMDs), or liquid crystal (LC) polarization rotators) are synchronized to send the same or different images to multiple vehicle occupants. This is called time sequencing of images.

[0005] In another aspect of the present disclosure, the user tracker includes at least one camera. The display may include a plurality of reflectors and a plurality of movable mounts, each movable mount being coupled to one of the plurality of reflectors so that each of the plurality of reflectors can move. A controller communicates with the plurality of movable mounts. The controller is programmed to instruct each of the plurality of movable mounts to align an image with the eyes of each of the plurality of vehicle occupants. Each of the plurality of reflectors may be a galvanized metal mirror. Each of the plurality of movable mounts may be a gimbal. The controller is programmed to control the light source and the SLM to reroute the SLM-encoded image using a holographic grating.

[0006] In another aspect of the present disclosure, a multi-view campfire display may include a digital micromirror device (DMD) positioned to receive an image encoded by the SLM. The DMD is configured to reroute the image encoded by the SLM for multiple vehicle occupants. The DMD communicates with a controller. The controller is programmed to control the DMD to reroute the image encoded by the SLM for multiple vehicle occupants based on the eye tracking signal so that each of the multiple vehicle occupants can see the image.

[0007] In another aspect of the present disclosure, the display includes a tunable liquid crystal (LC) polarization rotator positioned to receive an image encoded by the SLM. A controller is programmed to control the tunable LC polarization rotator to reroute the image encoded by the SLM for multiple on-board occupants based on eye tracking signals, so that each of the multiple on-board occupants can see the image. The tunable LC polarization rotator is positioned to receive an image encoded by the SLM. The controller is programmed to control the tunable LC polarization rotator to reroute the image encoded by the SLM for multiple on-board occupants based on eye tracking signals, so that each of the multiple on-board occupants can see the image. The multi-view campfire display may include a polarization beam splitter (PBS) downstream of the tunable LC polarization rotator, and the polarization beam splitter (PBS) is configured to reroute the image encoded by the SLM.

[0008] In another aspect of the present disclosure, a vehicle includes a vehicle body. The vehicle body defines a passenger compartment. The vehicle also includes the above-mentioned multi-view campfire display disposed in the passenger compartment.

[0009] The present disclosure also describes a method for displaying a hologram, which includes activating a light source to emit a light beam; modulating the light beam using a spatial light modulator (SLM) to encode an image; and controlling the polarization optical properties of the light beam to reroute the image encoded by the SLM for multiple vehicle occupants, so that each of the multiple vehicle occupants can see the image.

[0010] Other areas of applicability of the present disclosure will be apparent from the description provided herein below.It should be understood that the description and specific examples are provided for purposes of illustration only and are not intended to limit the scope of the present disclosure.

[0011] The above features and advantages and other features and advantages of the presently disclosed systems and methods are apparent from the following detailed description, including the claims and exemplary embodiments, when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present disclosure can be more fully understood from the detailed description and accompanying drawings, in which:

[0013] Figure 1 is a block diagram depicting a vehicle including a display;

[0014] Figure 2 yes Figure 1 a schematic isometric side view of the passenger compartment of the illustrated vehicle;

[0015] Figure 3 yes Figure 1 A schematic isometric side view of a vehicle passenger compartment depicting a three-dimensional (3D) hologram;

[0016] Figure 4 is a schematic diagram of a holographic display having a holographic grating;

[0017] Figure 5 is a schematic diagram of a holographic display having a digital micromirror device;

[0018] Figure 6 is a schematic diagram of a holographic display with an adjustable LC polarization rotator; and

[0019] Figure 7 is a flow chart of a method for displaying a hologram. DETAILED DESCRIPTION

[0020] Several examples of the present disclosure shown in the accompanying drawings will now be described in detail. Wherever possible, the same or similar reference numerals are used in the drawings and the description to represent the same or similar components or steps.

[0021] refer to Figure 1 , the vehicle 10 generally includes a chassis 12, a body 14, front wheels and rear wheels 17 and may be referred to as a "vehicle system". In the depicted embodiment, the vehicle 10 includes two front wheels 17a and two rear wheels 17b. The body 14 is disposed on the chassis 12 and substantially surrounds the components of the vehicle 10. The body 14 and the chassis 12 may together form a vehicle frame. Each wheel 17 is rotatably coupled to the chassis 12 near a respective corner of the body 14. The vehicle 10 includes a front axle 19 coupled to the front wheels 17a and a rear axle 25 coupled to the rear wheels 17b.

[0022] In various embodiments, the vehicle 10 may be an autonomous vehicle, and a control system 98 may be installed therein. The control system 98 may be referred to as a "system" or a system for a user to interact with one or more holographic displays 29. The vehicle 10, for example, is a vehicle that is automatically controlled to transport passengers from one location to another. The vehicle 10 may be configured as a truck, a sedan, a coupe, a sports utility vehicle (SUV), a recreational vehicle (RV), etc. In one embodiment, the vehicle 10 may be a so-called level 2, level 3, level 4, or level 5 automation system. Level 4 systems mean "high automation", which means that even if the human driver does not respond appropriately to the intervention request, the autonomous driving system can achieve specific driving mode performance in various aspects of the dynamic driving task. Level 5 systems mean "full automation", which means that the autonomous driving system can achieve full-time performance in various aspects of the dynamic driving task under several road and environmental conditions that the human driver can manage. In a level 3 vehicle, the vehicle system performs the entire dynamic driving task (DDT) within its design area. Only when a problem occurs or the vehicle is about to leave the area in which it can operate, and the vehicle 10 essentially "requires" the driver to take over, the vehicle operator needs to be responsible for the DDT contingency plan (fallback). In Level 2 vehicles, systems provide steering, braking / acceleration support, lane centering and adaptive cruise control. However, even when these systems are activated, the vehicle operator at the steering wheel must steer and constantly supervise the automated functions.

[0023] As shown, the vehicle 10 generally includes a propulsion system 20, a transmission system 22, a steering system 24, a braking system 26, a sensor system 28, an actuator system 30, at least one data storage device 32, at least one controller 34, and a communication system 36. In various embodiments, the propulsion system 20 may include an electric motor such as a traction motor and / or a fuel cell propulsion system. The vehicle 10 may also include a battery (or battery pack) 21 electrically connected to the propulsion system 20. Therefore, the battery 21 is configured to store electrical energy and provide electrical energy to the propulsion system 20. In certain embodiments, the propulsion system 20 may include an internal combustion engine. The transmission system 22 is configured to be able to transmit power from the propulsion system 20 to the wheels 17 according to a selectable speed ratio. According to various embodiments, the transmission system 22 may include a stepped automatic transmission, a continuously variable transmission, or other suitable transmission. The braking system 26 is configured to provide braking torque to the wheels 17. In various embodiments, the braking system 26 may include friction brakes, wire control brakes, regenerative braking systems (e.g., motors), and / or other suitable braking systems. The steering system 24 affects the position of the wheels 17 and may include a steering wheel 33. Although the present disclosure is depicted as including a steering wheel 33 for purposes of illustration, in some embodiments contemplated within the scope of the present disclosure, the steering system 24 may not include a steering wheel 33 .

[0024] The sensor system 28 includes one or more sensors 40 (i.e., sensing devices) that sense observable conditions of the external environment and / or the internal environment of the vehicle 10. The sensors 40 communicate with the controller 34 and may include, but are not limited to, one or more radars, one or more light detection and ranging (lidar) sensors, one or more proximity sensors, one or more odometers, one or more ground penetrating radar (GPR) sensors, one or more steering angle sensors, global navigation satellite system (GNSS) transceivers (e.g., one or more global positioning system (GPS) transceivers), one or more tire pressure sensors, one or more cameras 31, one or more gyroscopes, one or more accelerometers, one or more inclinometers, one or more speed sensors, one or more three-dimensional (3D) depth sensors 45, one or more ultrasonic sensors, one or more inertial measurement units (IMUs), thermal imaging sensors, one or more microphones 31, and / or other sensors. Each sensor 40 is configured to generate a signal indicating a sensed observable condition of the external environment and / or the internal environment of the vehicle 10 (i.e., sensor data). Because the sensor system 28 provides sensor data to the controller 34, the sensor system 28 and its sensors 40 are considered to be information sources (or simply "sources").

[0025] The 3D depth sensor 45 is configured to acquire multi-point distance information across a field of view (FoV) and measure the distance from the 3D depth sensor 45 to an object (e.g., hand 15) within the FoV of the 3D depth sensor 45. Therefore, the 3D depth sensor 45 can output a matrix of multiple distance readings on the FoV to obtain an accurate picture with full 3D depth perception. As a non-limiting example, the 3D depth sensor 45 can be a time-of-flight sensor and a stereo depth camera. The stereo depth camera can use the time-of-flight principle and infrared light to determine the depth of the scene and build a 3D model, while spatially mapping the interior of the passenger compartment 54 and the position of the body 13 of the vehicle user 11 and the position of the hand 15 of the vehicle user 11. The body 14 of the vehicle 10 defines the passenger compartment 54.

[0026] The actuator system 30 includes one or more actuator devices 42 that control one or more vehicle functions, such as but not limited to the propulsion system 20, the transmission system 22, the steering system 24, and the braking system 26. In various embodiments, the vehicle functions may also include interior and / or exterior vehicle functions, including but not limited to doors, trunk, and cabin functions such as air, music, lighting, etc.

[0027] One or more actuator devices 42 are configured as a haptic actuator 47. The haptic actuator 47 is configured to provide tactile feedback to the vehicle user 11. In other words, the haptic actuator 47 is configured to create a touch experience by applying an external force, vibration, or motion to the vehicle user 11 in the passenger compartment 54. As non-limiting examples, the haptic actuator 47 can be a piezoelectric actuator, an eccentric rotating mass (ERM) actuator, a linear resonant actuator (LRA), an ultrasonic actuator, and / or a non-contact haptic actuator, such as an air vortex ring actuator. The air vortex ring actuator can provide air pulses to the vehicle user 11. The haptic actuator 47 communicates with the controller 34, and the controller 34 is programmed to control the operation of the haptic actuator 47.

[0028] The data storage device 32 stores data for automatically controlling the vehicle 10. In various embodiments, the data storage device 32 stores a defined map of a navigable environment. In various embodiments, the defined map may be predefined by a remote system and obtained from the remote system. For example, the defined map may be assembled by a remote system and transmitted to the vehicle 10 (wirelessly and / or wired) and stored in the data storage device 32. The data storage device 32 may be part of the controller 34, rerouted from the controller 34, or part of the controller 34 and part of the rerouting system.

[0029] The vehicle 10 may also include one or more airbags 35 in communication with the controller 34 or another controller of the vehicle 10. The airbag 35 includes an inflatable bag and is configured to transition between a stowed configuration and a deployed configuration to mitigate the effects of external forces applied to the vehicle 10. The sensor 40 may include an airbag sensor, such as an IMU, configured to detect external forces and generate a signal indicating the magnitude of such external forces. The controller 34 is configured to command the airbag 35 to deploy based on signals from one or more sensors 40 (e.g., airbag sensors). Therefore, the controller 34 is configured to determine when the airbag 35 is deployed.

[0030] The controller 34 includes at least one processor 44 and a non-transitory computer readable storage device or medium 46. The processor 44 can be a custom or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor in several processors associated with the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), a macroprocessor, a combination thereof, or generally a device for executing instructions. The computer readable storage device or medium 46 can include volatile and non-volatile storage devices such as read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables when the processor 44 is turned off. The computer readable storage device or medium 46 can be implemented using a variety of storage devices, such as PROM (programmable read-only memory), EPROM (electrical PROM), EEPROM (electrically erasable PROM), flash memory, or any other electrical, magnetic, optical, or combination storage device capable of storing data (some of which represent executable instructions) used by the vehicle controller 34 when controlling the vehicle 10. The controller 34 of the vehicle 10 may be referred to as a "vehicle controller" and may be programmed to perform the method 100 described in detail below. Figure 7 ).

[0031] The instructions may include one or more rerouting programs, each of which includes an ordered list of executable instructions for implementing logical functions. When executed by the processor 44, the instructions receive and process signals from the sensor system 28, execute logic, calculations, methods and / or algorithms for automatically controlling components of the vehicle 10, and generate control signals to the actuator system 30 to automatically control components of the vehicle 10 based on the above logic, calculations, methods and / or algorithms. Although Figure 1 , a single controller 34 is shown, but embodiments of the vehicle 10 may include multiple controllers 34 that can communicate via a suitable communication medium or combination of communication media and cooperate to process sensor signals, execute logic, calculations, methods and / or algorithms, and generate control signals to automatically control functions of the vehicle 10. In various embodiments, one or more instructions of the controller 34 are included in the control system 98.

[0032] The vehicle 10 includes a user interface 23, which may be a touch screen in the instrument panel. The user interface 23 may include, but is not limited to, an alarm, such as one or more speakers 27 that provide audible sounds, tactile feedback in a vehicle seat or other target, one or more holographic displays 29, one or more microphones 31 (e.g., a microphone array), and / or other devices suitable for providing notifications to a vehicle user of the vehicle 10. The user interface 23 is in electronic communication with a controller 34 and is configured to receive input from a user (e.g., a vehicle operator or a passenger on the vehicle). For example, the user interface 23 may include a touch screen and / or buttons configured to receive input from a vehicle user 11 (e.g., a vehicle operator). Thus, the controller 34 is configured to receive input from a user via the user interface 23. Although Figure 1 2 , other microphones 31 may be part of the sensor system 28. The microphone 31 may be coupled directly to the headliner 52 of the vehicle 10 to capture voice commands from one or more passengers 11 in the passenger compartment 54 of the vehicle 10. However, it is contemplated that the microphone 31 may be coupled to other components of the vehicle 10. Regardless of its exact location, the microphone 31 is in communication with the controller 34. Thus, the microphone 31 may send sensor data (e.g., voice commands) to the controller 34.

[0033] The vehicle 10 may include one or more holographic displays 29 configured to display a 3D hologram 50 to one or more vehicle occupants 11. The holographic display 29 is configured to present one or more 3D holograms 50 to the vehicle occupants 11 within the passenger compartment 54. Figure 1 2 is shown as part of the user interface 23, but it is contemplated that the holographic display 29 may be directly coupled to the headliner 52 of the vehicle 10 to present one or more 3D holograms 50 to the onboard occupants 11 within the passenger compartment 54. However, it is also contemplated that the holographic display 29 may be attached to another component of the vehicle 10. Regardless of its exact location, the holographic display 29 communicates with the controller 34. Thus, the controller 34 is configured to control the operation of the holographic display 29.

[0034] The communication system 36 communicates with the controller 34 and is configured to wirelessly transmit information to and receive information from other remote vehicles 48, such as, but not limited to, other vehicles ("V2V" communication), infrastructure ("V2I" communication), remote systems of a remote call center (such as GENERALMOTORS' ON-STAR), and / or personal electronic devices, such as mobile phones. In the present disclosure, the term "remote vehicle" refers to a vehicle, such as an automobile, that is configured to transmit one or more signals to the vehicle 10 but is not physically connected to the vehicle 10. In one embodiment, the communication system 36 is a wireless communication system configured to communicate via a wireless local area network (WLAN) or by using cellular data communications using the IEEE 802.11 standard. However, additional or alternative communication methods such as dedicated short-range communication (DSRC) channels are also considered to be within the scope of the present disclosure. A DSRC channel refers to a one-way or two-way short-range to medium-range wireless communication channel designed specifically for automotive use and a set of corresponding protocols and standards. Thus, the communication system 36 may include one or more antennas and / or communication transceivers 37 for receiving and / or transmitting signals, such as collaborative sensing messages (CSM). The communication transceivers 37 may be considered sensors 40. The communication system 36 is configured to wirelessly transmit information between the vehicle 10 and another vehicle. In addition, the communication system 36 is also configured to wirelessly transmit information between the vehicle 10 and infrastructure or other vehicles.

[0035] refer to Figure 2 and Figure 3 , the vehicle 10 includes a passenger compartment 54 that is shaped and sized to accommodate a plurality of passengers (i.e., the vehicle occupants 11). In addition, the vehicle 10 includes a plurality of seats 56 disposed within the passenger compartment 54. The seats 56 are arranged in a campfire seating arrangement. In other words, one or more groups of seats 56 are placed opposite another group or groups of seats 56, similar to the way humans sit around a campfire. The passenger compartment 54 is defined by the roof lining 52 of the vehicle 10 and the vehicle floor 58.

[0036] Continue to refer Figure 2 and Figure 3, the haptic actuators 47 may be directly coupled to some or all of the seats 56 to facilitate providing haptic feedback to the vehicle occupants 11 seated on the seats 56. However, it is contemplated that the haptic actuators 47 may be coupled to other components within the passenger compartment 54 of the vehicle 10. At least some of the sensors 40 may be directly coupled to the vehicle's headliner 52 to facilitate sensing the movement of the vehicle occupants 11 and receiving voice commands from the vehicle occupants 11 within the passenger compartment 54. For example, the microphone 31 may be directly coupled to the vehicle's headliner 52 to capture voice commands from one or more vehicle occupants 11 (e.g., passengers) in the passenger compartment 54 of the vehicle 10. The 3D depth sensor 45 may be directly coupled to the vehicle's headliner 52 to facilitate sensing the 3D position of each vehicle user 11 in the passenger compartment 54 of the vehicle 10. The camera 31 may be directly coupled to the vehicle's headliner 52 to facilitate capturing images of the vehicle occupants 11 in the passenger compartment 54. The user tracker 43 may include one or more cameras 31 to track the movement of the head 69 and / or eyes 66 of the vehicle user 11 within the passenger compartment 54. The user tracker 43 may be referred to as an "eye tracker." The user tracker 43 may be directly coupled to the head lining 52 of the vehicle 10 to assist in tracking the head 69 and / or eyes 66 of the vehicle occupant 11 within the passenger compartment 54.

[0037] Continue to refer Figure 2 and Figure 3 , the holographic display 29 may be directly coupled to the headliner 52 of the vehicle 10 to present one or more 3D holograms 50 to the vehicle occupants 11 within the passenger compartment 54. However, it is contemplated that the holographic display 29 may be attached to another component of the vehicle 10. Figure 3 As shown, the vehicle occupants 11 can sit around a public display (i.e., holographic display 29) with a 360-degree outer edge. Each vehicle user 11 can see the public hologram 50 from his own perspective. Any vehicle user 11 can use their hands 15, eyes 66, and / or voice to interact with and operate the hologram 50. Multiple vehicle occupants 11 can collaboratively manipulate the public hologram 50 by simultaneously manipulating (e.g., by virtual touch, bending, stretching, folding, twisting, etc.) different parts of the hologram 50. When doing this, the perspectives (i.e., viewpoints) of other users on the public hologram will also change accordingly. The tactile actuator 47 can provide tactile feedback to the vehicle user 11 who is manipulating the hologram 50. The 3D hologram 50 spans 360 degrees around the holographic display 29 and may include, but is not limited to, an upcoming destination (e.g., a stadium), vehicle routes and progress, information about vehicle technology, Internet searches for anything, information shared in real time with other people at different locations outside the vehicle 10, and the like.

[0038] refer to Figure 4, the holographic display 29 may be called a floating autostereoscopic 3D display or a multi-view campfire display. The configuration of the holographic display 29 allows the number of displays to be reduced or the optical complexity for creating a 3D campfire hologram to be reduced. Therefore, the holographic display 29 is considered to be a true spatial floating holographic autostereoscopic 3D display. Therefore, the vehicle 10 may include fewer holographic displays 29 than seats 56. The holographic display 29 controls the polarization optical properties to reroute images for two or more viewers (i.e., the occupants 11 on the vehicle). The holographic display 29 may also be sequentially imaged for multiple users (i.e., the occupants 11 on the vehicle) with high-power lighting requirements. The holographic display 29 communicates electronically with the controller 34. The controller 34 also communicates with one or more user trackers 43. As described above, one or more cameras 31 may be configured as a user tracker 43 to track the movement of the head 69 and / or eyes 66 of the vehicle user 11 in the passenger compartment 54. The user tracker 43 is configured to track the head and eyes of the occupants 11 on the vehicle. For example, the user tracker 43 is configured to generate an eye tracking signal that indicates the position of the eyes of each vehicle occupant 11 .

[0039] Continue to refer Figure 4 , the holographic display 29 includes one or more light sources 60 in communication with the controller 34. Thus, the controller 34 can control the operation of the light sources 60. The light sources 60 are configured to emit one or more light beams 62. The holographic display 29 also includes a spatial light modulator (SLM) 64 positioned to receive the light beams 62 emitted by the light sources 60. Thus, the SLM 64 is in optical communication with the light sources 60. The SLM 64 is an object that applies some form of spatially varying modulation to the light beams. Thus, the SLM 64 is configured to modulate the light beams 62 and encode an image using the light beams 62.

[0040] Continue to refer Figure 4, the controller 34 communicates with the user tracker 43, the light source 60 and the SLM 64, and is programmed to receive the eye tracking signal. The controller 34 is also programmed to control the light source 60 and the SLM 64 to control the polarization optical properties (polarization optics) of the light beam 62 emitted by the light source 60 and modulated by the SLM 64 to reroute the image encoded by the SLM 64 for the vehicle occupant 11 based on the eye tracking signal, so that each vehicle occupant 11 can see the image, as discussed in detail below. At least two reflectors 68 are positioned to be in optical communication with the SLM 64 to receive the modulated light from the SLM 64. The reflector 68 acts as a reflector and is configured to reflect the light modulated by the SLM 64. As a non-limiting example, the reflector 68 can be made of galvanized metal and is therefore a galvanized metal mirror. The reflector 68 can be coated with various reflective coatings with or without polarization-related properties. The movable mount 70 is connected to all or some of the reflectors 68 to allow the reflectors 68 to move. As a non-limiting example, the movable mounts 70 may be gimbals to facilitate movement of the reflectors 68. The controller 34 is in communication with the movable mounts 70 and is programmed to command each movable mount 70 to align the image with the eyes of each vehicle occupant 11 based on the eye tracking signals received from the user tracker 43. Thus, the movable mounts 70 work in conjunction with the user tracker 43 to align the image with the position of the eyes 66 of the vehicle occupants 11.

[0041] Continue to refer Figure 4 , the controller 34 is programmed to control the light source 60 and the SLM 64 to use a holographic grating 72 to reroute the image encoded by the SLM 64. The holographic grating 72 is formed by the interference fringe field of two laser beams, whose standing wave pattern is exposed to a set of diffraction gratings of photosensitive materials. The holographic grating 72 is in optical communication with the light source 60 and the SLM 64 to reroute the image so that all vehicle occupants 11 can see the image. The holographic grating 72 can be described by the frequency of the grating lines:

[0042]

[0043] in:

[0044] f is the grating frequency in lines / mm;

[0045] Λ is the grating period in nm.

[0046] The grating equation can be expressed as:

[0047]

[0048] in:

[0049] θ is the angle of the incident light relative to the grating normal;

[0050] θ m is the mth order diffraction angle relative to the grating normal;

[0051] m is the diffraction order;

[0052] λ is the wavelength of illumination; and

[0053] Λ is the grating period in nm.

[0054] refer to Figure 5 , the holographic display 29 includes a digital micromirror device (DMD) 74 in optical communication with the reflector 68, instead of the holographic grating 72. The DMD 74 can encode images and is a digitally controlled micro-opto-electromechanical system (MOEMS) spatial light modulator (SLM), while it can also modulate the amplitude and direction of the light beam 62. The DMD 74 includes a series of reflectors that can create light patterns quickly, accurately and efficiently. Therefore, the DMD 74 is positioned to receive the image encoded by the SLM 64 after the light is reflected by the reflector 68. The DMD 74 is configured to reroute the image encoded by the SLM 64 for the on-board occupants 11. The DMD 74 communicates with the controller 34. The controller 64 is programmed to control the DMD 74 to reroute the image encoded by the SLM 64 for the on-board occupants 11 based on the eye tracking signal generated by the user tracker 43, so that each on-board occupant 11 can see the image.

[0055] refer to Figure 6, the holographic display 29 includes a tunable liquid crystal (LC) polarization rotator 76 that communicates with the controller 34 instead of the DMD 74 or the holographic grating 72. The tunable LC polarization rotator 76 is positioned to receive the image encoded by the SLM 64. The controller 34 is programmed to control the tunable LC polarization rotator 76 to reroute the image encoded by the SLM 64 for the on-board occupants 11 based on the eye tracking signal, so that each on-board occupant 11 can see the image. The LC polarization rotator 76 includes a liquid crystal variable retarder and a quartz zero-order quarter wave plate, and the fast axes of the LC retarder and the wave plate are oriented at 45° relative to each other. When a voltage is applied to the tunable liquid crystal (LC) polarization rotator 76, the image is rerouted. However, when no voltage is applied to the tunable liquid crystal (LC) polarization rotator 76, the image changes path and is rerouted. A polarization beam splitter (PBS) 78 is located downstream of the tunable LC polarization rotator 76. PBS 78 is configured to reroute the image encoded by SLM 64. A linear polarizer 80 is located downstream of PBS 78 to minimize polarization leakage. The polarization rotation wavelength is wavelength dependent. Therefore, the polarization rotation of the R, G, and B beams will be different, and therefore, there will be some polarization leakage through linear polarizer 80 after PBS 78 is aligned with the corresponding polarization state to help reduce or eliminate leakage.

[0056] Figure 7 1 is a flow chart of a method 100 for displaying a hologram to multiple vehicle occupants 11 within a vehicle 10. The method 100 begins at box 102. At box 102, the controller 34 activates the light source 60 to emit the light beam 60. The method 100 then proceeds to box 104. At box 104, the light beam 62 is modulated by the SLM 64 to encode an image. The method 100 then proceeds to box 106. At box 106, the polarization optical properties of the light beam 62 are controlled, as discussed in detail above, to reroute the image encoded by the SLM 64 so that each vehicle occupant 11 can see the image.

[0057] Although exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms included in the claims. The words used in the specification are descriptive rather than restrictive, and it is understood that various changes can be made without departing from the spirit and scope of the present disclosure. As previously mentioned, the features of the various embodiments can be combined to form other embodiments of the currently disclosed system and method that may not be explicitly described or illustrated. Although various embodiments can be described as having advantages or advantages over other embodiments or prior art implementations relative to one or more desired features, a person of ordinary skill in the art recognizes that one or more features or characteristics can be compromised to achieve the desired overall system properties, depending on the specific application and implementation. These properties may include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, applicability, weight, manufacturability, ease of assembly, etc. Therefore, embodiments described as less ideal than other embodiments or prior art implementations with respect to one or more features are not outside the scope of the present disclosure and may be ideal for specific applications.

[0058] The drawings are in simplified form and are not drawn to exact scale. Directional terms such as top, bottom, left, right, up, above, above, below, below, rear, and front may be used with respect to the drawings for convenience and clarity of description only. These directional terms and similar directional terms should not be construed as limiting the scope of the present disclosure in any way.

[0059] Although embodiments of the present disclosure are described herein, it should be understood that the disclosed embodiments are merely examples, and other embodiments in various alternative forms may be employed. The drawings are not necessarily drawn to scale; certain features may be magnified or minimized in order to show the details of a particular component. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching those skilled in the art to adopt the systems and methods of the present disclosure in different ways. As will be understood by those of ordinary skill in the art, the various features shown and described with reference to any of the figures may be combined with the features shown in one or more other figures to produce embodiments that are not explicitly shown or described. The combination of features shown provides representative embodiments of typical applications. However, various combinations and modifications of features consistent with the teachings of the present disclosure may be required for specific applications or implementations.

[0060] Embodiments of the present disclosure may be described herein in terms of functional and / or logical block components and various processing steps. It should be understood that such block components may be implemented by multiple hardware, software and / or firmware components configured to perform specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which may perform multiple functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that embodiments of the present disclosure may be practiced in conjunction with a variety of systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0061] For the sake of brevity, technologies related to signal processing, data fusion, signaling transmission, control and other functional aspects of the system (as well as the various operating components of the system) may not be described in detail herein. In addition, the connecting lines shown in the various figures contained herein are intended to represent example functional relationships and / or physical connections between the various elements. It should be noted that alternative or additional functional relationships or physical connections may exist in the embodiments of the present disclosure.

[0062] This description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be limited by such examples, as other modifications will be apparent after studying the drawings, the specification and the appended claims.

Claims

1. A multi-view campfire display comprising: a light source configured to emit a light beam; a spatial light modulator SLM positioned to receive the light beam emitted by the light source, wherein the SLM is configured to encode an image; a user tracker configured to track the heads and eyes of a plurality of vehicle occupants, wherein the user tracker is configured to generate an eye tracking signal, and the eye tracking signal indicates the position of the eyes of each of the plurality of vehicle occupants; and a controller in communication with the user tracker, the light source, and the SLM, wherein the controller is programmed to: receiving the eye tracking signal from the user tracker; and controlling polarization optical properties of the light beam emitted by the light source and modulated by the SLM to reroute the image encoded by the SLM for the plurality of vehicle occupants based on the eye tracking signal; The multi-view campfire display enables multiple vehicle occupants to see the images due to multiplexing.

2. The multi-view campfire display of claim 1, wherein: The user tracker includes at least one camera.

3. The multi-view campfire display of claim 2, further comprising a plurality of reflectors and a plurality of movable mounts, each of the movable mounts being coupled to one of the plurality of reflectors to allow each of the plurality of reflectors to move, wherein the controller communicates with the plurality of movable mounts, and the controller is programmed to command each of the plurality of movable mounts to align the image with the eyes of each of the plurality of vehicle occupants.

4. The multi-view campfire display of claim 3, wherein: Each of the plurality of reflectors is a galvanized metal reflector.

5. The multi-view campfire display of claim 4, wherein: Each of the plurality of movable mounts is a gimbal.

6. A multi-view campfire display according to claim 5, wherein the controller is programmed to control the light source and the SLM to use a holographic grating to reroute the image encoded by the SLM.

7. The multi-view campfire display according to claim 5 further includes a digital micromirror device (DMD), which is positioned to receive the image encoded by the SLM, and the DMD is also configured to reroute the image encoded by the SLM for the multiple vehicle occupants, the DMD communicates with the controller, and the controller is programmed to control the DMD to reroute the image encoded by the SLM for the multiple vehicle occupants based on the eye tracking signal, so that each of the multiple vehicle occupants sees the image.

8. The multi-view campfire display of claim 5, further comprising a tunable liquid crystal (LC) polarization rotator in communication with the controller, wherein the tunable LC polarization rotator is positioned to receive the image encoded by the SLM, wherein the controller is programmed to control the tunable LC polarization rotator to reroute the image encoded by the SLM for the multiple vehicle occupants based on the eye tracking signal so that each of the multiple vehicle occupants sees the image.

9. The multi-view campfire display of claim 8, further comprising a polarization beam splitter (PBS) located downstream of the tunable LC polarization rotator, and the PBS is configured to reroute the image encoded by the SLM.

10. The multi-view campfire display of claim 9, wherein each of the plurality of reflectors is positioned downstream of the PBS to align the image with the eyes of each of the plurality of vehicle occupants.

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